Educational Level and Coronary Heart Disease: A Study of Potential Confounding from Factors in Childhood and Adolescence Based on the Swedish 1969 Conscription Cohort

BackgroundPrevious studies suggest that the risk of coronary heart disease (CHD) may be related to educational level. In the present study, we looked at factors in childhood and adolescence as potential confounders of the relationship between educational level and risk of CHD. We also examined hypothesized mediation by socioeconomic factors in adulthood.MethodThe 1969 conscription cohort consisting of 49,321 Swedish men born in 1949 through 1951, who conscripted for military service in 1969/70, provided information on potential confounders. This was linked with register-based information on childhood social circumstances, education level, occupational class, income and job control in adulthood, and follow-up information on CHD during 1991 through 2007.ResultsThe relative risk of CHD increased with lower educational level. Among men with the lowest educational level, the relative risk of CHD was 1.81 (95% confidence interval, 1.60-2.05) compared with the highest educated group of men. Adjustment for childhood socioeconomic circumstances, and cognitive ability and behavior-related factors measured in late adolescence, attenuated the association considerably. Additional adjustment for socioeconomic position, income, and job control in adulthood did not attenuate the association further.ConclusionIt may be that educational level and risk of CHD are associated importantly owing to confounding from factors in childhood and adolescence.