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  • 51. Hedström, Anna Karin
    et al.
    Hössjer, Ola
    Stockholms universitet, Naturvetenskapliga fakulteten, Matematiska institutionen.
    Bellocco, Rino
    Ye, Weimin
    Trolle Lagerros, Ylva
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Insomnia in the context of short sleep increases suicide risk2021Ingår i: Sleep, ISSN 0161-8105, E-ISSN 1550-9109, Vol. 44, nr 4, artikel-id zsaa245Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Study objectives: The relationship between insomnia and suicide risk is not completely understood. We aimed to investigate the influence of insomnia on suicide risk, taking both sleep duration and depression into consideration.

    Methods: The present study is based on a Swedish prospective cohort study of 38,786 participants with a mean follow-up time of 19.2 years. Cox proportional hazards models with attained age as time-scale were used to estimate hazard ratios (HRs) of death by suicide with 95% confidence intervals (CI) for participants categorized by frequency of insomnia symptoms. Causal mediation analysis was performed to assess to what extent the relationship between insomnia and suicide risk is mediated by depression.

    Results: Insomnia was only associated with suicide risk among short sleepers, whereas no significant association was observed among those who slept 7 h/night or more. The total effect of insomnia in the context of short sleep on suicide risk, expressed on the HR scale, was 2.85 (95% CI 1.42-5.74). The direct effect was 2.25 (95% CI 1.12-4.54) and the indirect effect, mediated by depression, was 1.27 (95% CI 1.05-1.53). Of the total effect, 32% was mediated by depression. The association between insomnia and suicide risk became more pronounced with decreasing depressive symptoms (p value for trend <0.05).

    Conclusions: Insomnia in the context of short sleep increases suicide risk, both directly and indirectly by affecting the risk of depression. Abnormalities of sleep duration and insomnia symptoms should be evaluated when assessing suicide risk.

  • 52. Hedström, Anna Karin
    et al.
    Hössjer, Ola
    Stockholms universitet, Naturvetenskapliga fakulteten, Matematiska institutionen.
    Trolle Lagerros, Ylva
    Åkerstedt, Torbjorn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Short- and long-term mortality following hypnotic use2020Ingår i: Journal of Sleep Research, ISSN 0962-1105, E-ISSN 1365-2869, Vol. 29, nr 4, artikel-id e13061Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Potential long-term consequences of hypnotics remain controversial. We used the prospective Swedish National March Cohort, a study based on 41,695 participants with a mean follow-up duration of 18.9 years. Logistic regression models and Cox proportional hazards models with attained age as timescale were used to assess associations of hypnotic use with short- and long-term mortality. The proportion of subjects who initiated or discontinued hypnotic use during follow-up was substantial. All groups of hypnotics were associated with increased mortality within 2 years after a first prescription, with an overall OR of 2.38 (95% CI, 2.13-2.66). The association was more pronounced among subjects younger than 60 years (OR, 6.16; 95% CI, 3.98-9.52). There was no association between hypnotic use and long-term mortality. The association between hypnotic use and increased mortality was thus restricted to a relatively short period after treatment initiation, and may be explained in terms of confounding by indication.

  • 53. Hedström, Anna Karin
    et al.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Hillert, Jan
    Olsson, Tomas
    Alfredsson, Lars
    Shift work at young age is associated with increased risk for multiple sclerosis2011Ingår i: Annals of Neurology, ISSN 0364-5134, E-ISSN 1531-8249, Vol. 70, nr 5, s. 733-41Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: Environmental factors play a prominent role in multiple sclerosis (MS) etiology. The aim of this study was to investigate the potential association between shift work and MS risk, which has previously never been investigated.

    METHODS: This report is based on 2 population-based, case-control studies, 1 with incident cases (1,343 cases, 2,900 controls) and 1 with prevalent cases (5,129 cases, 4,509 controls). Using logistic regression, the occurrence of MS among subjects who have been exposed to shift work at various ages was compared with that of those who have never been exposed by calculating the odds ratio (OR) with a 95% confidence interval (CI).

    RESULTS: In both studies, there was a significant association between working shift at a young age and occurrence of MS (OR, 1.6; 95% CI, 1.2-2.1 in the incidence study and OR, 1.3; 95% CI, 1.0-1.6 in the prevalence study). In the incident study, the OR of developing MS was 2.0 (95% CI, 1.2-3.6) among those who had worked shifts for 3 years or longer before age 20 years, compared with those who had never worked shifts. The OR for the corresponding comparison in the prevalent study was 2.1 (95% CI, 1.3-3.4).

    INTERPRETATION: The observed association between shift work at a young age and occurrence of MS in 2 independent studies strengthens the notion of a true relationship. Consequences of shift work such as circadian disruption and sleep restriction are associated with disturbed melatonin secretion and enhanced proinflammatory responses and may thus be part of the mechanism behind the association.

  • 54. Hedström, Anna Karin
    et al.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Klareskog, Lars
    Alfredsson, Lars
    Relationship between shift work and the onset of rheumatoid arthritis2017Ingår i: RMD Open, E-ISSN 2056-5933, Vol. 3, nr 2, artikel-id e000475Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background Environmental factors play a prominent role in rheumatoid arthritis (RA) aetiology. Shift work has previously been associated with increased RA risk in females. The aim of this study was to investigate the potential association, including a dose-response association, between permanent night shift work, rotating shift work and day-oriented shift work and risk of developing anticitrullinated peptide antibodies (ACPA)-positive and ACPA-negative RA.

    Methods The present report is based on a population-based, case-control study with incident cases of RA (1951 cases and 2225 controls matched by age, gender and residential area). Using logistic regression, occurrence of RA among subjects who have been exposed to different kinds of shift work was compared with that among those who have never been exposed by calculating the OR with a 95% CI.

    Results Rotating shift work and day-oriented shift work increased the risk of developing ACPA-positive RA (OR 1.3, 95% CI 1.0 to 1.7 and OR 1.3, 95% CI 1.0 to 1.6), but not ACPA-negative RA. Permanent night shift work appeared to be a protective factor both against ACPA-positive RA (OR 0.7, 95% CI 0.6 to 0.9) and ACPA-negative RA (OR 0.8, 95% CI 0.6 to 1.0). For both subsets of RA, significant trends showed a lower risk of developing RA with increasing duration of permanent night shift work (p value for trend 0.002 vs 0.04).

    Conclusions Sleep restriction as a consequence of shift work is associated with several biological effects among which changes in melatonin production may be involved. The present epidemiological findings of a complex relationship between sleep patterns and different forms of RA may be of importance for increasing the understanding of the pathophysiology of RA.

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  • 55.
    Holding, Benjamin C.
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet.
    Sundelin, Tina
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Schiller, Helena
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Axelsson, John
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Sleepiness, sleep duration, and human social activity: An investigation into bidirectionality using longitudinal time-use data2020Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 117, nr 35, s. 21209-21217Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Daytime sleepiness impairs cognitive ability, but recent evidence suggests it is also an important driver of human motivation and behavior. We aimed to investigate the relationship between sleepiness and a behavior strongly associated with better health: social activity. We additionally aimed to investigate whether a key driver of sleepiness, sleep duration, had a similar relationship with social activity. For these questions, we considered bidirectionality, time of day, and differences between workdays and days off. Over 3 wk, 641 working adults logged their behavior every 30 min, completed a sleepiness scale every 3 h, and filled a sleep diary every morning (rendering >292,000 activity and >70,000 sleepiness datapoints). Using generalized additive mixed-effect models, we analyzed potential nonlinear relationships between sleepiness/sleep duration and social activity. Greater sleepiness predicted a substantial decrease in the probability of social activity (odds ratio 95% CI = 0.34 to 0.35 for days off), as well as a decreased duration of such activity when it did occur. These associations appear especially robust on days off and in the evenings. Social duration moderated the typical time-of-day pattern of sleepiness, with, for example, extended evening socializing associated with lower sleepiness. Sleep duration did not robustly predict next-day social activity. However, extensive social activity (>5 h) predicted up to 30 min shorter subsequent sleep duration. These results indicate that sleepiness is a strong predictor of voluntary decreases in social contact. It is possible that bouts of sleepiness lead to social withdrawal and loneliness, both risk factors for mental and physical ill health.

  • 56.
    Ingre, Michael
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    van Leeuwen, Wessel M. A.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Second generation three process model (TMP) of alertness for better assessment of individual risks2013Konferensbidrag (Övrigt vetenskapligt)
  • 57.
    Ingre, Michael
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    van Leeuwen, Wessel M A
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Klemets, T
    Ullvetter, C
    Hough, S
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Karlsson, D
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Validating and extending the three process model (TPM) of alertness in airline operations.2014Ingår i: Journal of Sleep Research, ISSN 0962-1105, E-ISSN 1365-2869, Vol. 23, nr S1, s. 264-264, artikel-id P836Artikel i tidskrift (Övrigt vetenskapligt)
  • 58.
    Ingre, Michael
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    van Leeuwen, Wessel M. A.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Klemets, Tomas
    Ullvetter, Christer
    Hough, Stephen
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Karlsson, David
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Validating and Extending the Three Process Model of Alertness in Airline Operations.2014Ingår i: PLOS ONE, E-ISSN 1932-6203, Vol. 9, nr 10, s. e108679-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sleepiness and fatigue are important risk factors in the transport sector and bio-mathematical sleepiness, sleep and fatigue modeling is increasingly becoming a valuable tool for assessing safety of work schedules and rosters in Fatigue Risk Management Systems (FRMS). The present study sought to validate the inner workings of one such model, Three Process Model (TPM), on aircrews and extend the model with functions to model jetlag and to directly assess the risk of any sleepiness level in any shift schedule or roster with and without knowledge of sleep timings. We collected sleep and sleepiness data from 136 aircrews in a real life situation by means of an application running on a handheld touch screen computer device (iPhone, iPod or iPad) and used the TPM to predict sleepiness with varying level of complexity of model equations and data. The results based on multilevel linear and non-linear mixed effects models showed that the TPM predictions correlated with observed ratings of sleepiness, but explorative analyses suggest that the default model can be improved and reduced to include only two-processes (S+C), with adjusted phases of the circadian process based on a single question of circadian type. We also extended the model with a function to model jetlag acclimatization and with estimates of individual differences including reference limits accounting for 50%, 75% and 90% of the population as well as functions for predicting the probability of any level of sleepiness for ecological assessment of absolute and relative risk of sleepiness in shift systems for safety applications.

  • 59.
    Ingre, Michael
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Ekstedt, Mirjam
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Periodic self-rostering in shift work: correspondence between objective work hours, work hour preferences (personal fit), and work schedule satisfaction2012Ingår i: Scandinavian Journal of Work, Environment and Health, ISSN 0355-3140, E-ISSN 1795-990X, Vol. 38, nr 4, s. 327-336Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives The main objective of the present study was to investigate relative personal fit as the association between rated needs and preferences for work hours, on the one hand, and actual work hours, on the other hand, in three groups (hospital, call-center, and police) working with periodic self-rostering. We also examined the association between personal fit and satisfaction with the work schedule and preference for a fixed and regular shift schedule, respectively. Methods We collected questionnaire data and objective work hour data over 6-12 months from the computerized self-rostering system. The response rate of the questionnaire was 69% at the hospital and call-center and 98% among the police. In total, 29 433 shifts for 285 shift workers were included in the study. Data was analyzed by means of mixed ANOVA, Kendal tau correlations and ordinal (proportional odds) logistic regression. Results The results show that evening types worked relatively more hours during the evening and night hours compared to morning types as an indication of relative personal fit. Relative personal fit was also found for long shift, short rest, and morning-, evening- and night-shift frequency, but only personal fit related to morning, evening and night-shift was associated with satisfaction with work hours. Reported conflicts at the workplace about work hours and problems with lack of predictability of time for family/leisure activities, was associated with poor satisfaction and a preference for a fixed shift schedule. Conclusions The present study shows that periodic self-rostering is associated with relative personal fit, in particular with respect to night, evening, and morning work. Personal fit seems to be associated with satisfaction with work hours and may be a moderator of tolerance to shift work exposure.

  • 60.
    Ivarsson, Malena
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen.
    Anderson, Martin
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Lindblad, Frank
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Uppsala University, Sweden.
    The effect of violent and nonviolent video games on heart rate variability, sleep, and emotions in adolescents with different violent gaming habits2013Ingår i: Psychosomatic Medicine, ISSN 0033-3174, E-ISSN 1534-7796, Vol. 75, nr 4, s. 390-396Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective To study cardiac, sleep-related, and emotional reactions to playing violent (VG) versus nonviolent video games (NVG) in adolescents with different gaming habits.

    Methods Thirty boys (aged 13-16 years, standard deviation = 0.9), half of them low-exposed (≤1 h/d) and half high-exposed (≥3 h/d) to violent games, played a VG/NVG for 2 hours during two different evenings in their homes. Heart rate (HR) and HR variability were registered from before start until next morning. A questionnaire about emotional reactions was administered after gaming sessions and a sleep diary on the following mornings.

    Results During sleep, there were significant interaction effects between group and gaming condition for HR (means [standard errors] for low-exposed: NVG 63.8 [2.2] and VG 67.7 [2.4]; for high-exposed: NVG 65.5 [1.9] and VG 62.7 [1.9]; F(1,28) = 9.22, p = .005). There was also a significant interaction for sleep quality (low-exposed: NVG 4.3 [0.2] and VG 3.7 [0.3]); high-exposed: NVG 4.4 [0.2] and VG 4.4 [0.2]; F(1,28) = 3.51, p = .036, one sided), and sadness after playing (low-exposed: NVG 1.0 [0.0] and VG 1.4 [0.2]; high-exposed: NVG 1.2 [0.1] and VG 1.1 [0.1]; (F(1,27) = 6.29, p = .009, one sided).

    Conclusions Different combinations of the extent of (low versus high) previous VG and experimental exposure to a VG or an NVG are associated with different reaction patterns-physiologically, emotionally, and sleep related. Desensitizing effects or selection bias stand out as possible explanations.

  • 61. Jansson, Catarina
    et al.
    Alexanderson, Kristina
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Clinically diagnosed insomnia and risk of all-cause and diagnosis-specific sickness absence: a nationwide Swedish prospective cohort study.2013Ingår i: Scandinavian Journal of Public Health, ISSN 1403-4948, E-ISSN 1651-1905, Vol. 41, nr 7, s. 712-721Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aims: Insomnia is a large health problem. In some prior studies, positive associations between insomnia symptoms and sickness absence have been observed. There is, however, no previous nationwide cohort study of clinically diagnosed insomnia and risk of incident sickness absence. Methods: Prospective nationwide cohort study based on Swedish population-based registers including all 4,956,358 individuals registered as living in Sweden on 31 December 2004/2005, aged 17-64 years, not on disability pension, old-age pension or on-going sickness absence. Those having insomnia inpatient or outpatient care, defined as having at least one admission/specialist visit with a main or secondary diagnosis of disorders of initiating and maintaining sleep [insomnias] (ICD-10: G47.0) during 2000/2001-2005, were compared to those with no such care. All-cause and diagnosis-specific incident sickness absence were followed during 2006-2010. Incidence rate ratios (IRRs) and 95% confidence intervals (CIs) were estimated by Cox proportional hazards regression. Results: In models adjusted for prior sickness absence, socio-demographic factors and inpatient and specialized outpatient care, associations between insomnia and increased risks of all-cause sickness absence (IRR 1.18, 95% CI 1.04-1.35) and sickness absence due to mental diagnoses (IRR 1.75, 95% CI 1.36-2.25) were observed. After further adjustment for insomnia medications these associations disappeared. No associations between insomnia and risk of sickness absence due to cancer, circulatory or musculoskeletal diagnoses, or injuries, were observed. Conclusions: In this nationwide cohort study, we observed increased risks of all-cause sickness absence and sickness absence due to mental diagnoses after adjustment for several potential confounders that disappeared after further adjustment for insomnia medications.

  • 62. Kaida, Kosuke
    et al.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Takahashi, Masaya
    Vestergren, Peter
    Gillberg, Mats
    Lowden, Arne
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Portin, Christian
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Performance prediction by sleepiness-related subjective symptoms during 26-hour sleep deprivation2008Ingår i: Sleep and Biological Rhythms, ISSN 1446-9235, E-ISSN 1479-8425, Vol. 6, s. 234-241Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sleepiness is a major cause of lower productivity and higher risk of accidents in various work situation. Developing sleepiness monitoring techniques is important to important to improve work efficiency and to reduce accident risk, so that people can take a rest/break in appropriate timing before an accident or a mistake occurs. The aim of the present study are (1) to explain subjective sleepiness using sleep-related symptoms, and (2) to examine which symptoms are useful to predict performance errors. Participants were healthy paid volunteers (six males, six females; mean ± SD, 31.5 ± 10.74 years). Participants took part in 26-h sleep deprivation. During sleep deprivation, they carried out several performance tasks every 3 h and an hourly rating of questionnaires to evaluate subjective symptoms including two types of Karolinska Sleepiness Scale (KSS). The present study confirmed that performance errors can be predicted by subjective symptoms. While mental fatigue was correlated to KSS scores linearly, eye-related subjective symptoms showed quadratic correlation to KSS. By taking into consideration this noteworthy relationskap between subjective symptoms and sleepiness, more accurate introspection of sleepiness and performance errors prediction (detection) may be possible.

  • 63.
    Kecklund, Göran
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Ingre, Michael
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    What characterizes good and bad shift schedules?2013Konferensbidrag (Refereegranskat)
  • 64.
    Kecklund, Göran
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Milia, Lee Di
    Axelsson, John
    Lowden, Arne
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    20th International Symposium on Shiftwork and Working Time: Biological Mechanisms, Recovery, and Risk Management in the 24-h Society2012Ingår i: Chronobiology International, ISSN 0742-0528, E-ISSN 1525-6073, Vol. 29, nr 5, s. 531-536Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This dedicated issue of Chronobiology International is devoted to the selected proceedings of the 20th International Symposium on Shift Work and Working Time held in Stockholm, Sweden, 28 June to 1 July 2011. It constitutes the fifth such issue of the journal since 2004 dedicated to the selected proceedings to the meetings of the Working Time Society. The key theme of the 20th Symposium was "Biological Mechanisms, Recovery, and Risk Management in the 24-h Society." The collection of papers of this dedicated issue represents the best of contemporary research on the effects of night and rotating shift schedules on worker health and safety. The contents cover such topics as sleep restriction, injuries, health, and performance of night work and rotating shiftwork, plus light treatment as a countermeasure against the circadian disruption of shiftwork. The majority of the papers are observational field studies, including some of large sample size, and three studies are well-designed laboratory experiments. (Author correspondence: goran.kecklund@stress.su.se ).

  • 65.
    Kecklund, Göran
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Söderström, Marie
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Att motverka sömnstörning: orsaker och behandling2008Ingår i: Preventiv medicin: Teori och praktik, Studentlitteratur, Lund , 2008, s. 115-126Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 66. Knutsson, Anders
    et al.
    Alfredsson, Lars
    Karlsson, Berndt
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Fransson, Eleonor I.
    Westerholm, Peter
    Westerlund, Hugo
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Breast cancer among shift workers: results of the WOLF longitudinal cohort study2013Ingår i: Scandinavian Journal of Work, Environment and Health, ISSN 0355-3140, E-ISSN 1795-990X, Vol. 39, nr 2, s. 170-177Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: The aim of this study was to investigate whether shift work (with or without night work) is associated with increased risk of breast cancer. METHODS: The population consisted of 4036 women. Data were obtained from WOLF (Work, Lipids, and Fibrinogen), a longitudinal cohort study. Information about baseline characteristics was based on questionnaire responses and medical examination. Cancer incidence from baseline to follow-up was obtained from the national cancer registry. Two exposure groups were identified: shift work with and without night work. The group with day work only was used as the reference group in the analysis. Cox regression analysis was used to calculate relative risk. RESULTS: In total, 94 women developed breast cancer during follow-up. The average follow-up time was 12.4 years. The hazard ratio for breast cancer was 1.23 [95% confidence interval (95% CI) 0.70-2.17] for shifts without night work and 2.02 (95% CI 1.03-3.95) for shifts with night work. When including only women <60 years of age, the risk estimates were 1.18 (95% CI 0.67-2.07) for shifts without night work, and 2.15 (95% CI 1.10-4.21) for shifts with night work. CONCLUSIONS: Our results indicate an increased risk for breast cancer among women who work shifts that includes night work.

  • 67. Koenig, Julian
    et al.
    Abler, Birgit
    Agartz, Ingrid
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Stockholm, Sweden.
    Andreassen, Ole A.
    Anthony, Mia
    Bär, Karl-Jürgen
    Bertsch, Katja
    Brown, Rebecca C.
    Brunner, Romuald
    Carnevali, Luca
    Critchley, Hugo D.
    Cullen, Kathryn R.
    de Geus, Eco J. C.
    Dziobek, Isabel
    Ferger, Marc D.
    Fischer, Håkan
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Biologisk psykologi.
    Flor, Herta
    Gaebler, Michael
    Gianaros, Peter J.
    Giummarra, Melita J.
    Greening, Steven G.
    Guendelman, Simon
    Heathers, James A. J.
    Herpertz, Sabine C.
    Hu, Mandy X.
    Jentschke, Sebastian
    Kaess, Michael
    Kaufmann, Tobias
    Klimes-Dougan, Bonnie
    Koelsch, Stefan
    Krauch, Marlene
    Kumral, Deniz
    Lamers, Femke
    Lee, Tae-Ho
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Stockholm, Sweden.
    Lin, Feng
    Lotze, Martin
    Makovac, Elena
    Mancini, Matteo
    Mancke, Falk
    Månsson, Kristoffer N.T.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Klinisk psykologi. Karolinska Institutet, Stockholm County Council.
    Manuck, Stephen B.
    Mather, Mara
    Meeten, Frances
    Min, Jungwon
    Mueller, Bryon
    Muench, Vera
    Nees, Frauke
    Nga, Lin
    Nilsonne, Gustav
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Stockholm, Sweden.
    Ordonez Acuna, Daniela
    Osnes, Berge
    Ottaviani, Cristina
    Penninx, Brenda W. J. H.
    Ponzio, Allison
    Poudel, Govinda R.
    Reinelt, Janis
    Ren, Ping
    Sakaki, Michiko
    Schumann, Andy
    Sørensen, Lin
    Specht, Karsten
    Straub, Joana
    Tamm, Sandra
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Stockholm, Sweden: Oxford University, Oxford, UK.
    Thai, Michelle
    Thayer, Julian F.
    Ubani, Benjamin
    van der Mee, Denise J.
    van Velzen, Laura S.
    Ventura-Bort, Carlos
    Villringer, Arno
    Watson, David R.
    Wei, Luqing
    Wendt, Julia
    Westlund Schreiner, Melinda
    Westlye, Lars T.
    Weymar, Mathias
    Winkelmann, Tobias
    Wu, Guo-Rong
    Yoo, Hyun Joo
    Quintana, Daniel S.
    Cortical thickness and resting-state cardiac function across the lifespan: A cross-sectional pooled mega-analysis2021Ingår i: Psychophysiology, ISSN 0048-5772, E-ISSN 1469-8986, Vol. 58, nr 7, artikel-id e13688Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Understanding the association between autonomic nervous system [ANS] function and brain morphology across the lifespan provides important insights into neurovisceral mechanisms underlying health and disease. Resting-state ANS activity, indexed by measures of heart rate [HR] and its variability [HRV] has been associated with brain morphology, particularly cortical thickness [CT]. While findings have been mixed regarding the anatomical distribution and direction of the associations, these inconsistencies may be due to sex and age differences in HR/HRV and CT. Previous studies have been limited by small sample sizes, which impede the assessment of sex differences and aging effects on the association between ANS function and CT. To overcome these limitations, 20 groups worldwide contributed data collected under similar protocols of CT assessment and HR/HRV recording to be pooled in a mega-analysis (N = 1,218 (50.5% female), mean age 36.7 years (range: 12–87)). Findings suggest a decline in HRV as well as CT with increasing age. CT, particularly in the orbitofrontal cortex, explained additional variance in HRV, beyond the effects of aging. This pattern of results may suggest that the decline in HRV with increasing age is related to a decline in orbitofrontal CT. These effects were independent of sex and specific to HRV; with no significant association between CT and HR. Greater CT across the adult lifespan may be vital for the maintenance of healthy cardiac regulation via the ANS—or greater cardiac vagal activity as indirectly reflected in HRV may slow brain atrophy. Findings reveal an important association between CT and cardiac parasympathetic activity with implications for healthy aging and longevity that should be studied further in longitudinal research.

  • 68.
    Lasselin, Julie
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. University of Duisburg-Essen, Germany; Karolinska Institutet, Sweden.
    Karshikoff, Bianka
    Axelsson, John
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Benson, Sven
    Engler, Harald
    Schedlowski, Manfred
    Jones, Mike
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Andreasson, Anna
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Macquarie University, Australia.
    Fatigue and sleepiness responses to experimental inflammation and exploratory analysis of the effect of baseline inflammation in healthy humans2020Ingår i: Brain, behavior, and immunity, ISSN 0889-1591, E-ISSN 1090-2139, Vol. 83, s. 309-314Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Inflammation is believed to be a central mechanism in the pathophysiology of fatigue. While it is likely that dynamic of the fatigue response after an immune challenge relates to the corresponding cytokine release, this lacks evidence. Although both fatigue and sleepiness are strong signals to rest, they constitute distinct symptoms which are not necessarily associated, and sleepiness in relation to inflammation has been rarely investigated. Here, we have assessed the effect of an experimental immune challenge (administration of lipopolysaccharide, LPS) on the development of both fatigue and sleepiness, and the associations between increases in cytokine concentrations, fatigue and sleepiness, in healthy volunteers. In addition, because chronic-low grade inflammation may represent a risk factor for fatigue, we tested whether higher baseline levels of inflammation result in a more pronounced development of cytokine-induced fatigue and sleepiness. Data from four experimental studies was combined, giving a total of 120 subjects (LPS N = 79, 18 (23%) women; Placebo N = 69, 12 (17%) women). Administration of LPS resulted in a stronger increase in fatigue and sleepiness compared to the placebo condition, and the development of both fatigue and sleepiness closely paralleled the cytokine responses. Individuals with stronger increases in cytokine concentrations after LPS administration also suffered more from fatigue and sleepiness (N = 75), independent of gender. However, there was no support for the hypothesis that higher baseline inflammatory markers moderated the responses in fatigue or sleepiness after an inflammatory challenge. The results demonstrate a tight connection between the acute inflammatory response and development of both fatigue and sleepiness, and motivates further investigation of the involvement of inflammation in the pathophysiology of central fatigue.

  • 69.
    Lasselin, Julie
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Rehman, Javaid-Ur
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Axelsson, John
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Effect of long-term sleep restriction and subsequent recovery sleep on the diurnal rhythms of white blood cell subpopulations.2015Ingår i: Brain, behavior, and immunity, ISSN 0889-1591, E-ISSN 1090-2139, Vol. 47, nr SI, s. 93-99Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    While acute modifications of sleep duration induces a wide array of immune function alterations, less is known of how longer periods with insufficient sleep affect immune functions and how they return to normal once recovery sleep is obtained. The purpose of the present study was to investigate the effects of five days of restricted sleep and a subsequent 7-day period of sleep recovery on white blood cell (WBC) subpopulation count and diurnal rhythms. Nine healthy males participated in a sleep protocol consisting of two baseline days (8h of sleep/night), five nights with restricted sleep (4h of sleep/night) and seven days of recovery sleep (8h of sleep/night). During nine of these days, blood was drawn hourly during night-time end every third hour during daytime, and differential WBC count was analyzed. Gradual increase across the days of sleep restriction was observed for total WBC (p<.001), monocytes (p<.001), neutrophils (p<.001) and lymphocytes (p<.05). Subsequent recovery sleep resulted in a gradual decrease in monocytes (p<.001) and lymphocytes (p=.001), but not in neutrophils that remained elevated over baseline level at the end of the 7-day recovery period. These effects were associated with altered diurnal rhythms of total WBC and neutrophils, restricted sleep being associated with higher levels during the night and at awakening, resulting in a flattening of the rhythm. The diurnal alterations were reversed when recovery sleep was allowed, although the amplitude of total WBC, neutrophils and monocytes was increased at the end of the recovery period in comparison to baseline. Altogether, these data show that long-term sleep restriction leads to a gradual increase of circulating WBC subpopulations and alterations of the respective diurnal rhythms. Although some of the effects caused by five days of restricted sleep were restored within the first days of recovery, some parameters were not back to baseline even after a period of seven recovery days.

  • 70.
    Leineweber, Constanze
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Theorell, Töres
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska institutet, Sverige.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Alexanderson, Kristina
    Westerlund, Hugo
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Inflytande över arbetstiden och sjuknärvaro/sjukfrånvaro2013Ingår i: Arbetsmarknad & Arbetsliv, ISSN 1400-9692, E-ISSN 2002-343X, Vol. 19, nr 4, s. 87-99Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [sv]

    Flexibla arbetstider blir allt vanligare. De förväntas underlätta verksamhetens förmåga att hantera arbetstoppar, tillgodose anställdas behov av livsbalans samt möjliggöra bättre hälsa och arbetsprestation. Flexibilitet skapas ofta genom att de anställda ges inflytande över arbetstiderna. Vetenskaplig kunskap om sambandet mellan arbetstidskontroll och sjukfrånvaro/sjuknärvaro saknas nästan helt. I föreliggande studie undersöks sambandet mellan arbetstidskontroll samt dess underdimensioner och självrapporterad sjukfrånvaro/sjuknärvaro i ett representativt urval av den arbetande befolkningen i Sverige.

  • 71.
    Lekander, Mats
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Andreasson, Anna Nixon
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Ekman, Rolf
    Ingre, Michael
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjorn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Axelsson, John
    Subjective health perception in healthy young men changes in response to experimentally restricted sleep and subsequent recovery sleep2013Ingår i: Brain, behavior, and immunity, ISSN 0889-1591, E-ISSN 1090-2139, Vol. 34, s. 43-46Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sleep and subjective health are both prospectively related to objective indices of health and health care use. Here, we tested whether five days with restricted sleep and subsequent recovery days affect subjective health and is related to increased levels of circulating IL-6 and TNF-α and fatigue. Nine healthy men (23-28years) went through a 6-week sleep protocol with subjects as their own controls in a repeated measures design with a total of 11 nights in a sleep laboratory. The experimental part of the protocol included three baseline days (sleep 23-07h), five days with sleep restriction (03-07h) and three recovery days (23-07h) in the sleep laboratory. Subjective health and fatigue was recorded daily. Eight blood samples were drawn each day (every third hour) on 8days of the protocol and analyzed with respect to IL-6 and TNF-α. Subjective health deteriorated gradually during restricted sleep (p=.002) and returned to baseline levels after three days of recovery. IL-6 and TNF-α did not change significantly. Fatigue increased gradually during sleep restriction (p=.001), which significantly contributed to the association between restricted sleep and subjective health. The study is the first to show that subjective health is directly responsive to changes in sleep length and related to increased fatigue. Thus, subjective health is differently appraised after manipulation of one of its presumed determinants. Larger experimental studies would be beneficial to further distinguish causation from association regarding the underpinnings of subjective health.

  • 72.
    Lindblad, Frank
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Backman, Lena
    Lundin, A
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Sleep, stress and eating attitudes predict concentration at school2011Ingår i: Salud (i) Ciencia, ISSN 1667-8982, E-ISSN 1667-8990, Vol. 18, nr 2, s. 142-146Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Sleep, stress and eating habits may affect concentration in school. These factors are probably interrelated, but have never been studied together as predictors of concentration. The purpose of this study, based on secondary analysis of previously collected data, was to evaluate if/how low sleep quality, perceived stress and negative attitudes to eating at school predict self-reported concentration difficulties in school in 11-15-year-olds. Methods: 1 124 students (grades 6-9) from 14 schools (a representative sample from a metropolitan area) filled in a questionnaire at school with questions about socio-demographic data, sleep, perceived stress, school eating attitudes and concentration in school. Results: Logistic regression analysis with mutual adjustment for all predictors, as well as for grade and gender yielded an odds ratio (OR) for the stress component "pressure" of 3.05 (95% confidence interval [CI] = 2.73-4.38), OR = 1.70 (1.20-2.42) for school eating attitude, and OR = 2.57 (1.78-3.71) for difficulties sleeping. Conclusion: Sleep, stress, and eating attitudes independently seem to predict perceived problems of concentration in school, suggesting that a multi-focus approach of life-style patterns may be suitable when trying to improve students' ability to concentrate in school.

  • 73. Lindsäter, Elfin
    et al.
    Axelsson, Erland
    Salomonsson, Sigrid
    Santoft, Fredrik
    Ljótsson, Brjánn
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Hedman-Lagerlöf, Erik
    Cost-Effectiveness of Therapist-Guided Internet-Based Cognitive Behavioral Therapy for Stress-Related Disorders: Secondary Analysis of a Randomized Controlled Trial2019Ingår i: Journal of Medical Internet Research, E-ISSN 1438-8871, Vol. 21, nr 9, artikel-id e14675Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Stress-related disorders are associated with significant suffering, functional impairment, and high societal costs. Internet-based cognitive behavioral therapy (ICBT) is a promising treatment for stress-related disorders but has so far not been subjected to health economic evaluation.

    Objective: The objective of this study was to evaluate the cost-effectiveness and cost-utility of ICBT for patients with stress-related disorders in the form of adjustment disorder (AD) or exhaustion disorder (ED). We hypothesized that ICBT, compared with a waitlist control (WLC) group, would generate improvements at low net costs, thereby making it cost-effective.

    Methods: Health economic data were obtained in tandem with a randomized controlled trial of a 12-week ICBT in which patients (N=100) were randomized to an ICBT (n=50) or a WLC (n=50) group. Health outcomes and costs were surveyed pre-and posttreatment. We calculated incremental cost-effectiveness ratios (ICERs) based on remission rates and incremental cost-utility ratios (ICURs) based on health-related quality of life. Bootstrap sampling was used to assess the uncertainty of our results.

    Results: The ICER indicated that the most likely scenario was that ICBT led to higher remission rates compared with the WLC and was associated with slightly larger reductions in costs from pre- to posttreatment. ICBT had a 60% probability of being cost-effective at a willingness to pay (WTP) of US $0 and a 96% probability of being cost-effective at a WTP of US $1000. The ICUR indicated that ICBT also led to improvements in quality of life at no net societal cost. Sensitivity analyses supported the robustness of our results.

    Conclusions: The results suggest that ICBT is a cost-effective treatment for patients suffering from AD or ED. Compared with no treatment, ICBT for these patients yields large effects at no or minimal societal net costs.

  • 74. Lindsäter, Elin
    et al.
    Axelsson, Erland
    Salomonsson, Sigrid
    Santoft, Fredrik
    Ejeby, Kersti
    Ljótsson, Brjann
    Åkerstedt, Torbjorn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Hedman-Lagerlöf, Erik
    Internet-Based Cognitive Behavioral Therapy for Chronic Stress: A Randomized Controlled Trial2018Ingår i: Psychotherapy and Psychosomatics, ISSN 0033-3190, E-ISSN 1423-0348, Vol. 87, nr 5, s. 296-305Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Prolonged exposure to stress can lead to substantial suffering, impairment and societal costs. However, access to psychological treatment is limited. Internet-based cognitive behavioral therapy (ICBT) can be effective in reducing symptoms of stress, but little is known of its effects in clinical samples. The aim of this study was to investigate the efficacy of ICBT for patients suffering from chronic stress, operationalized as adjustment disorder (AD) and exhaustion disorder (ED). Methods: A total of 100 adults diagnosed with AD or ED were randomly assigned to a 12-week ICBT (n = 50) or waitlist control condition (n = 50). Primary outcome was the level of perceived stress (PSS). Secondary outcomes included several mental health symptom domains as well as functional impairment and work ability. All outcomes were assessed at baseline, after treatment and at the 6-month follow-up. The study was preregistered at Clinicaltrials.gov: NCT02540317. Results: Compared to the control condition, patients in the ICBT group made large and significant improvements on the PSS (d = 1.09) and moderate to large improvements in secondary symptom domains. Effects were maintained at the 6-month follow-up. There was no significant between-group effect on functional impairment or work ability. Conclusions: A relatively short ICBT is indicated to be effective in reducing stress-related symptoms in a clinical sample of patients with AD and ED, and has the potential to substantially increase treatment accessibility. Results must be replicated, and further research is needed to understand the relationship between symptom reduction, functional impairment and work ability.

  • 75. Lindsäter, Elin
    et al.
    Axelsson, Erland
    Salomonsson, Sigrid
    Santoft, Fredrik
    Ljótsson, Brjánn
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Hedman-Lagerlöf, Erik
    The mediating role of insomnia severity in internet-based cognitive behavioral therapy for chronic stress: Secondary analysis of a randomized controlled trial2021Ingår i: Behaviour Research and Therapy, ISSN 0005-7967, E-ISSN 1873-622X, Vol. 136, artikel-id 103782Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this study was to investigate insomnia symptom severity as a putative mediator of treatment response in therapist-guided internet-based cognitive behavioral therapy (ICBT) for chronic stress, using data from a randomized controlled trial. Participants (N = 100) were randomized to 12 weeks of ICBT or to a waitlist control condition (WLC). Insomnia severity was assessed weekly with the Insomnia Severity Index (ISI), as were the stress-related outcomes the Perceived Stress Scale (PSS) and the Shirom-Melamed Burnout Questionnaire (SMBQ). Latent growth models indicated that ICBT (vs. WLC) predicted a decrease in insomnia severity (alpha-path), and that growth in insomnia severity was predictive of growth in perceived stress and exhaustion (beta-paths). Most importantly, there were also significant indirect effects (alpha beta products) such that the beneficial effects of ICBT on perceived stress and exhaustion were mediated by a reduction in insomnia symptom severity (PSS: alpha beta =-0.44, 95% CI [-0.92,-0.14]; SMBQ: alpha beta =-0.08, 95% CI [-0.15, 0.04]). Explorative analysis of moderated mediation showed that more severe insomnia symptoms at baseline were associated with larger mediated effects. We conclude that reducing insomnia severity could be of importance for achieving successful treatment outcomes in ICBT for chronic stress.

  • 76.
    Lowden, Arne
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjorn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Magnusson Hanson, Linda
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Westerlund, Hugo
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Daylight exposure in the in-door working population in Sweden, relation to sleep, wakefulness and health2013Konferensbidrag (Refereegranskat)
  • 77.
    Lowden, Arne
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Nagai, Roberta
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Karolinska Institutet, Sweden.
    Mild, Kjell Hansson
    Hillert, Lena
    Effects of evening exposure to electromagnetic fields emitted by 3G mobile phones on health and night sleep EEG architecture2019Ingår i: Journal of Sleep Research, ISSN 0962-1105, E-ISSN 1365-2869, Vol. 28, nr 4, artikel-id UNSP e12813Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Studies on sleep after exposure to radiofrequency electromagnetic fields have shown mixed results. We investigated the effects of double-blind radiofrequency exposure to 1,930-1,990 MHz, UMTS 3G signalling standard, time-averaged 10 g specific absorption rate of 1.6 W kg(-1) on self-evaluated sleepiness and objective electroencephalogram architecture during sleep. Eighteen subjects aged 18-19 years underwent 3.0 hr of controlled exposure on two consecutive days 19:45-23:00 hours (including 15-min break); active or sham prior to sleep, followed by full-night 7.5 hr polysomnographic recordings in a sleep laboratory. In a cross-over design, the procedure was repeated a week later with the second condition. The results for sleep electroencephalogram architecture showed no change after radiofrequency exposure in sleep stages compared with sham, but power spectrum analyses showed a reduction of activity within the slow spindle range (11.0-12.75 Hz). No differences were found for self-evaluated health symptoms, performance on the Stroop colour word test during exposure or for sleep quality. These results confirm previous findings that radiofrequency post-exposure in the evening has very little influence on electroencephalogram architecture but possible on spindle range activity.

  • 78.
    Lowden, Arne
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institute, Sweden.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institute, Sweden.
    Assessment of a new dynamic light regimen in a nuclear power control room without windows on quickly rotating shiftworkers-effects on health, wakefulness, and circadian alignment: a pilot study2012Ingår i: Chronobiology International, ISSN 0742-0528, E-ISSN 1525-6073, Vol. 29, nr 5, s. 641-649Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of the study was to test whether a new dynamic light regime would improve alertness, sleep, and adaptation to rotating shiftwork. The illumination level in a control room without windows at a nuclear power station was ∼200 lux (straight-forward horizontal gaze) using a weak yellow light of 200 lux, 3000 K (Philips Master TLD 36 W 830). New lighting equipment was installed in one area of the control room above the positions of the reactor operators. The new lights were shielded from the control group by a distance of >6 m, and the other operators worked at desks turned away from the new light. The new lights were designed to give three different light exposures: (i) white/blue strong light of 745 lux, 6000 K; (ii) weak yellow light of 650 lux, 4000 K; and (iii) yellow moderate light of 700 lux, 4000 K. In a crossover design, the normal and new light exposures were given during a sequence of three night shifts, two free days, two morning shifts, and one afternoon shift (NNN + MMA), with 7 wks between sessions. The operators consisted of two groups; seven reactor operators from seven work teams were at one time exposed to the new equipment and 16 other operators were used as controls. The study was conducted during winter with reduced opportunities of daylight exposure during work, after night work, or before morning work. Operators wore actigraphs, filled in a sleep/wake diary, including ratings of sleepiness on the Karolinska Sleepiness Scale (KSS) every 2 h, and provided saliva samples for analysis of melatonin at work (every 2nd h during one night shift and first 3 h during one morning shift). Results from the wake/sleep diary showed the new light treatment increased alertness during the 2nd night shift (interaction group × light × time, p < .01). Time of waking was delayed in the light condition after the 3rd night shift (group × light, p < .05), but the amount of wake time during the sleep span increased after the 2nd night shift (p < .05), also showing a tendency to affect sleep efficiency (p < .10). Effects on circadian phase were difficult to establish given the small sample size and infrequent sampling of saliva melatonin. Nonetheless, it seems that appropriate dynamic light in rooms without windows during the dark Nordic season may promote alertness, sleep, and better adaptation to quickly rotating shiftwork. (Author correspondence: arne.lowden@stress.su.se ).

  • 79.
    Lowden, Arne
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Ingre, Michael
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Wiholm, Clairy
    Hillert, Lena
    Kuster, Niels
    Nilsson, Jens P.
    Arnetz, Bengt
    Sleep after mobile phone exposure in subjects with mobile phone-related symptoms2011Ingår i: Bioelectromagnetics, ISSN 0197-8462, E-ISSN 1521-186X, Vol. 32, nr 1, s. 4-14Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Several studies show increases in activity for certain frequency bands (10-14 Hz) and visually scored parameters during sleep after exposure to radiofrequency electromagnetic fields. A shortened REM latency has also been reported. We investigated the effects of a double-blind radiofrequency exposure (884 MHz, GSM signaling standard including non-DTX and DTX mode, time-averaged 10 g psSAR of 1.4 W/kg) on self-evaluated sleepiness and objective EEG measures during sleep. Forty-eight subjects (mean age 28 years) underwent 3 h of controlled exposure (7:30-10:30 PM; active or sham) prior to sleep, followed by a full-night polysomnographic recording in a sleep laboratory. The results demonstrated that following exposure, time in Stages 3 and 4 sleep (SWS, slow-wave sleep) decreased by 9.5 min (12%) out of a total of 78.6 min, and time in Stage 2 sleep increased by 8.3 min (4%) out of a total of 196.3 min compared to sham. The latency to Stage 3 sleep was also prolonged by 4.8 min after exposure. Power density analysis indicated an enhanced activation in the frequency ranges 0.5-1.5 and 5.75-10.5 Hz during the first 30 min of Stage 2 sleep, with 7.5-11.75 Hz being elevated within the first hour of Stage 2 sleep, and bands 4.75-8.25 Hz elevated during the second hour of Stage 2 sleep. No pronounced power changes were observed in SWS or for the third hour of scored Stage 2 sleep. No differences were found between controls and subjects with prior complaints of mobile phone-related symptoms. The results confirm previous findings that RF exposure increased the EEG alpha range in the sleep EEG, and indicated moderate impairment of SWS. Furthermore, reported differences in sensitivity to mobile phone use were not reflected in sleep parameters.

  • 80.
    Magnusson Hanson, Linda
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Chungkham, Holendro Singh
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Westerlund, Hugo
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    The Role of Sleep Disturbances in the Longitudinal Relationship Between Psychosocial Working Conditions, Measured by Work Demands and Support, and Depression.2014Ingår i: Sleep, ISSN 0161-8105, E-ISSN 1550-9109, Vol. 37, nr 12, s. 1977-1985Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Study Objectives: Because work demands and lack of social support seem to be prospectively linked to sleep problems, and sleep problems are linked to depression, sleep problems may play a role in the relationship between these work characteristics and depressive symptoms. In order to shed more light on this relationship, the current study investigated whether disturbed sleep is a mediator in the longitudinal relationships between work demands, social support, and depression.

    Design: Longitudinal cohort study with repeated survey measures on four occasions.

    Setting: Swedish workforce.

    Participants: 2,017 working participants from the Swedish Longitudinal Occupational Survey of Health in 2006, 2008, 2010, and 2012.

    Measurements and results: Work demands (four items) and social support (six items) were assessed with the Demand Control Questionnaire, disturbed sleep (four items) with the Karolinska Sleep Questionnaire, and depressive symptoms with a brief subscale (six items) from the Symptom Checklist. Autoregressive longitudinal mediation models using structural equation modeling were tested. The work characteristics, and disturbed sleep, were found to be separately associated with depressive symptoms in subsequent waves. However, only demands were found to be longitudinally related to subsequent disturbed sleep. The longitudinal autoregressive models supported a weak mediating role of disturbed sleep in the relationship between demands and depressive symptoms (standardized beta 0.008, P < 0.001), but not between support and depressive symptoms.

    Conclusions: These results indicate that higher demands at work might cause an increase in depressive symptoms, in part, by increasing disturbed sleep, although the mediated effect was relatively small compared to the total effect.

  • 81.
    Magnusson Hanson, Linda
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Chungkham, Holendro Singh
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Westerlund, Hugo
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Kivimäki, Mika
    Does disturbed sleep mediate the longitudinal relationshipbetween work stress and depression?2013Ingår i: European Journal of Epidemiology, ISSN 0393-2990, E-ISSN 1573-7284, Vol. 28, s. S57-S58Artikel i tidskrift (Övrigt vetenskapligt)
  • 82.
    Magnusson Hanson, Linda L.
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Näswall, Katharina
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen.
    Leineweber, Constanze
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Theorell, Töres
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Westerlund, Hugo
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen.
    Cross-lagged relationships between workplace demands, control, support, and sleep problems2011Ingår i: Sleep, ISSN 0161-8105, E-ISSN 1550-9109, Vol. 34, nr 10, s. 1403-1410Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    STUDY OBJECTIVES: Sleep problems are experienced by a large part of the population. Work characteristics are potential determinants, but limited longitudinal evidence is available to date, and reverse causation is a plausible alternative. This study examines longitudinal, bidirectional relationships between work characteristics and sleep problems.

    DESIGN: Prospective cohort/two-wave panel.

    SETTING: Sweden.

    PARTICIPANTS: 3065 working men and women approximately representative of the Swedish workforce who responded to the 2006 and 2008 waves of the Swedish Longitudinal Occupational Survey of Health (SLOSH).

    INTERVENTIONS: N/A.

    MEASUREMENTS AND RESULTS: Bidirectional relationships between, on the one hand, workplace demands, decision authority, and support, and, on the other hand, sleep disturbances (reflecting lack of sleep continuity) and awakening problems (reflecting feelings of being insufficiently restored), were investigated by structural equation modeling. All factors were modeled as latent variables and adjusted for gender, age, marital status, education, alcohol consumption, and job change. Concerning sleep disturbances, the best fitting models were the "forward" causal model for demands and the "reverse" causal model for support. Regarding awakening problems, reciprocal models fitted the data best.

    CONCLUSIONS: Cross-lagged analyses indicates a weak relationship between demands at Time 1 and sleep disturbances at Time 2, a "reverse" relationship from support T1 to sleep disturbances T2, and bidirectional associations between work characteristics and awakening problems. In contrast to an earlier study on demands, control, sleep quality, and fatigue, this study suggests reverse and reciprocal in addition to the commonly hypothesized causal relationships between work characteristics and sleep problems based on a 2-year time lag. CITATION: Magnusson Hanson LL; Åkerstedt T; Näswall K; Leineweber C; Theorell T; Westerlund H. Cross-lagged relationships between workplace demands, control, support, and sleep problems.

  • 83. Mallon, Lena
    et al.
    Broman, Jan-Erik
    Akerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Hetta, Jerker
    Insomnia in Sweden: a population-based survey2014Ingår i: Sleep Disorders, ISSN 2090-3545, E-ISSN 2090-3553, Vol. 2014, s. 843126-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aims. Estimate the prevalence of insomnia and examine effects of sex, age, health problems, sleep duration, need for treatment, and usage of sleep medication. Methods. A sample of 1,550 subjects aged 18-84 years was selected for a telephone interview. The interview was completed by 1,128 subjects (72.8%). Results. 24.6% reported insomnia symptoms. Insomnia disorder, that is, insomnia symptoms and daytime consequences, was reported by 10.5%. The prevalence was similar among all age groups, with the exception of women aged 40-49 years who demonstrated a significantly higher prevalence, 21.6%. Having at least one physical or psychiatric disorder was reported by 82.8% of subjects with insomnia disorder. Mean sleep duration for subjects with insomnia disorder was 5.77 hours on weeknights and 7.03 hours on days off/weekends. The corresponding figures for subjects without insomnia disorder were 7.04 hours and 7.86 hours, respectively. Among those with insomnia disorder 62.5% expressed a need for treatment, and 20.0% used prescribed sleep medication regularly. Conclusions. Insomnia disorder is highly prevalent in the population. There are significant associations between insomnia disorder and physical and psychiatric disorders. A majority of subjects with insomnia disorder expressed a need for treatment, indicating a public health problem.

  • 84. Miley-Akerstedt, Anna
    et al.
    Jelic, Vesna
    Marklund, Kristina
    Walles, Håkan
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institute, Sweden.
    Hagman, Goran
    Andersson, Christin
    Lifestyle Factors Are Important Contributors to Subjective Memory Complaints among Patients without Objective Memory Impairment or Positive Neurochemical Biomarkers for Alzheimer's Disease2018Ingår i: Dementia and Geriatric Cognitive Disorders Extra, E-ISSN 1664-5464, Vol. 8, nr 3, s. 439-452Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background/Aims: Many patients presenting to a memory disorders clinic for subjective memory complaints do not show objective evidence of decline on neuropsychological data, have nonpathological biomarkers for Alzheimer's disease, and do not develop a neurodegenerative disorder. Lifestyle variables, including subjective sleep problems and stress, are factors known to affect cognition. Little is known about how these factors contribute to patients' subjective sense of memory decline. Understanding how lifestyle factors are associated with the subjective sense of failing memory that causes patients to seek a formal evaluation is important both for diagnostic workup purposes and for finding appropriate interventions and treatment for these persons, who are not likely in the early stages of a neurodegenerative disease. The current study investigated specific lifestyle variables, such as sleep and stress, to characterize those patients that are unlikely to deteriorate cognitively. Methods: Two hundred nine patients (mean age 58 years) from a university hospital memory disorders clinic were included. Results: Sleep problems and having much to do distinguished those with subjective, but not objective, memory complaints and non-pathological biomarkers for Alzheimer's disease. Conclusions: Lifestyle factors including sleep and stress are useful in characterizing subjective memory complaints from objective problems. Inclusion of these variables could potentially improve health care utilization efficiency and guide interventions.

  • 85. Miley-Åkerstedt, Anna
    et al.
    Hetta, Jerker
    Åkerstedt, Torbjorn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institute, Sweden.
    Criteria for self-reported quantitative sleep characteristics of individuals who sought medical help for disturbed sleep - a survey of a representative sample of the Swedish population2018Ingår i: Nature and Science of Sleep, ISSN 1179-1608, Vol. 10, s. 295-301Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: The public often seeks rule-of-thumb criteria for good or poor sleep, with a particular emphasis on sleep duration, sleep latency, and the number of awakenings each night. However, very few criteria are available. Aim: The present study sought to identify such criteria. Methods: Whether or not a person has sought medical help for sleep problems was selected as an indicator of poor sleep. The group that was studied constituted a representative sample of the general Swedish population (N=1,128), with a response rate of 72.8%. Results: Logistic regression analysis, with an adjustment for age and gender, showed an increased OR for a weekday sleep duration of <= 6 hour, (OR >2, and for <5 hour: OR >6). For weekend sleep, the value was <= 6 hour (OR >2). For awakenings per night, the critical value was >= 2 (OR >2, and for awakenings: OR >9), and for a sleep latency the critical value was >= 30 minutes (OR >2, and for >= 45 minutes: OR >6). Adding difficulties falling asleep and early morning awakening (considered qualitative because of the reflected difficulty), led to the elimination of all the quantitative variables, except for the number of awakenings. The addition of negative effects on daytime functioning and sleep being a big problem resulted in the elimination of all the other predictors except age. Conclusion: It was concluded that weekday sleep <= 6 hour, >= 2 awakenings/night, and a sleep latency of >= 30 minutes, can function as criteria for poor sleep, but that qualitative sleep variables take over the role of quantitative ones, probably because they represent the integration of quantitative indicators of sleep.

  • 86.
    Nilsonne, G.
    et al.
    Karolinska Institutet, Sweden.
    Tamm, S.
    Karolinska Institutet, Sweden.
    Schwarz, J.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Almeida, R.
    Fischer, H.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Biologisk psykologi.
    Kecklund, G.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Lekander, M.
    Karolinska Institutet, Sweden.
    Fransson, P.
    Åkerstedt, T.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Increased global FMRI signal variability after partial sleep deprivation: Findings from the Stockholm sleepy brain study2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Introduction: Neural correlates of sleep deprivation are not fully understood and the difference between young and older adults in this regard has received little attention. We aimed to investigate the effect of partial sleep deprivation on resting state connectivity.

    Methods: 30 younger (20–30 years) and 23 older (65–75 years) healthy participants underwent MR imaging after normal sleep and partial sleep deprivation (3 h sleep). We acquired two runs of eyes-open resting state functional magnetic resonance images. Participants were monitored with eye-tracking to ensure their eyes remained open during scanning.

    Results: Global signal variability, defined as log-transformed standard deviation of average gray matter signal, was increased following partial sleep deprivation (0.16 [0.07, 0.24], p = 0.0004). In contrast to previous studies, we did not find that partial sleep deprivation inhibited connectivity in the default mode network, nor in other major networks investigated.

    Conclusion: Sleep deprivation caused increased global signal variability. This novel finding should be confirmed using independent data. Our finding of no difference in default mode connectivity in the sleep deprived state, could possibly be due to stricter monitoring of participants’ wakefulness compared to some earlier studies.

  • 87.
    Nilsonne, Gustav
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Axelsson, John
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Ingre, Michael
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Diurnal Variation of Circulating Interleukin-6 in Humans: A Meta-Analysis2016Ingår i: PLOS ONE, E-ISSN 1932-6203, Vol. 11, nr 11, artikel-id e0165799Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The pleiotropic cytokine interleukin-6 (IL-6) has been proposed to contribute to circadian regulation of sleepiness by increasing in the blood at night. Earlier studies have reported diurnal variation of IL-6, but phase estimates are conflicting. We have therefore performed a meta-analysis on the diurnal variation of circulating IL-6. Studies were included if they reported IL-6 in plasma or serum recorded at least twice within 24 hours in the same individual. A systematic search resulted in the inclusion of 43 studies with 56 datasets, for a total of 1100 participants. Individual participant data were available from 4 datasets with a total of 56 participants. Mixed-effects meta-regression modelling confirmed that IL-6 varied across the day, the most conspicuous effect being a trough in the morning. These results stand in contrast to earlier findings of a peak in the evening or night, and suggest that diurnal variation should be taken into account in order to avoid confounding by time of day in studies of IL-6 in plasma or serum.

  • 88.
    Nilsonne, Gustav
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Tamm, Sandra
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    D'Onofrio, Paolo
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Schwarz, Johanna F. A.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Fischer, Frida M.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Effect of partial sleep deprivation on self-rated health and sickness2013Konferensbidrag (Övrigt vetenskapligt)
  • 89.
    Nilsonne, Gustav
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Tamm, Sandra
    Karolinska Institutet, Sweden.
    D'Onofrio, Paolo
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Schwarz, Johanna
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Fischer, Håkan
    Karolinska Institutet, Sweden.
    Detection of facial mimicry by electromyography during fMRI scanning2013Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    We investigated whether electromyography (EMG) could be used to detect facial mimicry during fMRI scanning.

    EMG activity in the superciliary corrugator muscle increased when participants viewed angry faces.

  • 90.
    Nilsonne, Gustav
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Tamm, Sandra
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    D'Onofrio, Paolo
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Thuné, Hanna
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Schwarz, Johanna F A
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Petrovic, P
    Fischer, H
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Effect of partial sleep deprivation on empathy for pain in an fMRI experiment2014Konferensbidrag (Refereegranskat)
  • 91.
    Nilsonne, Gustav
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Tamm, Sandra
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    D'Onofrio, Paolo
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Thuné, Hanna
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Schwarz, Johanna F A
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Petrovic, P
    Fischer, Håkan
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Effect of partial sleep deprivation on empathy for pain in an fMRI experiment2014Konferensbidrag (Övrigt vetenskapligt)
  • 92.
    Nilsonne, Gustav
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Tamm, Sandra
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Månsson, Kristoffer N. T.
    Åkerstedt, Torbjörn
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Leukocyte telomere length and hippocampus volume: a meta-analysis [version 1; referees: 2 approved]2015Ingår i: F1000 Research, E-ISSN 2046-1402, Vol. 4, artikel-id 1073Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Leukocyte telomere length has been shown to correlate to hippocampus volume, but effect estimates differ in magnitude and are not uniformly positive. This study aimed primarily to investigate the relationship between leukocyte telomere length and hippocampus gray matter volume by meta-analysis and secondarily to investigate possible effect moderators. Five studies were included with a total of 2107 participants, of which 1960 were contributed by one single influential study. A random-effects meta-analysis estimated the effect to r = 0.12 [95% CI -0.13, 0.37] in the presence of heterogeneity and a subjectively estimated moderate to high risk of bias. There was no evidence that apolipoprotein E (APOE) genotype was an effect moderator, nor that the ratio of leukocyte telomerase activity to telomere length was a better predictor than leukocyte telomere length for hippocampus volume. This meta-analysis, while not proving a positive relationship, also is not able to disprove the earlier finding of a positive correlation in the one large study included in analyses. We propose that a relationship between leukocyte telomere length and hippocamus volume may be mediated by transmigrating monocytes which differentiate into microglia in the brain parenchyma.

  • 93.
    Nilsonne, Gustav
    et al.
    Karolinska Institutet, Sweden.
    Tamm, Sandra
    Karolinska Institutet, Sweden.
    Schwarz, Johanna
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Almeida, Rita
    Fischer, Håkan
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Biologisk psykologi.
    Kecklund, Göran
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Fransson, Peter
    Åkerstedt, Torbjörn
    Karolinska Institutet, Sweden.
    Intrinsic brain connectivity after partial sleep deprivation in young and older adults2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Introduction: Sleep deprivation has been reported to affect intrinsic brain connectivity, notably in the default mode network, but studies to date have shown inconsistent effects and have largely included young participants. We therefore aimed to investigate effects of partial sleep deprivation on intrinsic brain connectivity in young and older participants. Methods: Participants aged 20-30 (n = 30) and 65-75 (n = 23) years underwent partial sleep deprivation (3 h sleep) in a cross-over design, with two eyes-open resting state functional magnetic resonance imaging (fMRI) runs in each session. We assessed intrinsic brain connectivity using independent components analysis (ICA) as well as seed-region analyses of functional connectivity, and also analysed global signal variability, regional homogeneity, and the amplitude of low-frequency fluctuations. Participants were monitored with eye-tracking to ensure they did not fall asleep during scanning. Results: Sleep deprivation caused increased global signal variability, defined as log-transformed standard deviation of average gray matter signal (0.16 [0.07, 0.24], p = 0.0004). In contrast to previous studies, sleep deprivation did not cause major changes in investigated resting state networks, nor did it cause changes in regional homogeneity. Younger participants had higher functional connectivity in most examined resting state networks, as well as higher regional homogeneity in brain areas including anterior and posterior cingulate cortex. Conclusions: We show for the first time that partial sleep deprivation caused increased global signal variability. This outcome should be examined as a potential biomarker for sleepiness using independent data. Unlike a few earlier studies, we did not find less default mode connectivity in the sleep deprived state, possibly because of stricter monitoring of participants' wakefulness.

  • 94.
    Nilsonne, Gustav
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden .