Background: Exposure to childhood out-of-home care (foster family and residential care) is associated with an increased risk of ill-health and disability in adulthood, but the risk for cardiovascular disease has not previously been studied longitudinally.

Methods: This was a national cohort study generated from linkage of a range of population-based registers, resulting in a national cohort of 881 731 of whom 26 310 (3.0%) had a history of out-of-home care. The study population, born 1972 to 1981, was followed from age 18 to age 39 to 48 years for hospitalizations and death.

Results: After adjusting for year of birth and maternal education, individuals with a history of childhood out-of-home-care experienced a doubling of the risk for coronary disease (hazard ratio; 95% confidence interval: 2.05; 1.74-2.41) and stroke (hazard ratio 1.85; 1.59-2.15), compared with the general population, with similar estimates for men and women. Women with a history of out-of-home care had a more than doubled risk for cigarette smoking in early pregnancy, with a relative risk of 2.26; (2.18-2.34) and a moderately increased risk for gestational diabetes relative risk 1.49 (1.19-1.86). There was marked attenuation (40% to 90%) in effect estimates for disease and risk factors after further control for cohort members educational achievement at age 15-16 years.

Conclusions: A history of childhood out-of-home care was associated with a doubled risk of early cardiovascular disease events. Cigarette smoking and educational underachievement were the main identified risk factors.