In-car nocturnal blue light exposure improves motorway driving: a randomized controlled trial
2012 (English)In: PLoS ONE, ISSN 1932-6203, Vol. 7, no 10, e46750- p.Article in journal (Refereed) Published
Prolonged wakefulness greatly decreases nocturnal driving performance. The development of in-car countermeasures is a future challenge to prevent sleep-related accidents. The aim of this study is to determine whether continuous exposure to monochromatic light in the short wavelengths (blue light), placed on the dashboard, improves night-time driving performance. In this randomized, double-blind, placebo-controlled, cross-over study, 48 healthy male participants (aged 20-50 years) drove 400 km (250 miles) on motorway during night-time. They randomly and consecutively received either continuous blue light exposure (GOLite, Philips, 468 nm) during driving or 2*200 mg of caffeine or placebo of caffeine before and during the break. Treatments were separated by at least 1 week. The outcomes were number of inappropriate line crossings (ILC) and mean standard deviation of the lateral position (SDLP). Eight participants (17%) complained about dazzle during blue light exposure and were removed from the analysis. Results from the 40 remaining participants (mean age ± SD: 32.9±11.1) showed that countermeasures reduced the number of inappropriate line crossings (ILC) (F(2,91.11) = 6.64; p<0.05). Indeed, ILC were lower with coffee (12.51 [95% CI, 5.86 to 19.66], p = 0.001) and blue light (14.58 [CI, 8.75 to 22.58], p = 0.003) than with placebo (26.42 [CI, 19.90 to 33.71]). Similar results were found for SDLP. Treatments did not modify the quality, quantity and timing of 3 subsequent nocturnal sleep episodes. Despite a lesser tolerance, a non-inferior efficacy of continuous nocturnal blue light exposure compared with caffeine suggests that this in-car countermeasure, used occasionally, could be used to fight nocturnal sleepiness at the wheel in blue light-tolerant drivers, whatever their age. More studies are needed to determine the reproducibility of data and to verify if it can be generalized to women. TRIAL REGISTRATION: ClinicalTrials.govNCT01070004.
Place, publisher, year, edition, pages
2012. Vol. 7, no 10, e46750- p.
Milled rumble strips, Centre of the lane, Narrow rural roads, Sleepy drivers, Driving behaviour, Driving simulator study
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:su:diva-82096DOI: 10.1371/journal.pone.0046750ISI: 000310050200013PubMedID: 23094031Local ID: P2951OAI: oai:DiVA.org:su-82096DiVA: diva2:565669