Educational class inequalities in the incidence of coronary heart disease in Europe

Objective To estimate the burden of social inequalities in coronary heart disease (CHD) and to identify their major determinants in 15 European populations. Methods The MORGAM (MOnica Risk, Genetics, Archiving and Monograph) study comprised 49 cohorts of middle-aged European adults free of CHD (110 928 individuals) recruited mostly in the mid-1980s and 1990s, with comparable assessment of baseline risk and follow-up procedures. We derived three educational classes accounting for birth cohorts and used regression-based inequality measures of absolute differences in CHD rates and HRs (ie, Relative Index of Inequality, RII) for the least versus the most educated individuals. Results N=6522 first CHD events occurred during a median follow-up of 12 years. Educational class inequalities accounted for 343 and 170 additional CHD events per 100 000 person-years in the least educated men and women compared with the most educated, respectively. These figures corresponded to 48% and 71% of the average event rates in each gender group. Inequalities in CHD mortality were mainly driven by incidence in the Nordic countries, Scotland and Lithuania, and by 28-day case-fatality in the remaining central/South European populations. The pooled RIIs were 1.6 (95% CI 1.4 to 1.8) in men and 2.0 (1.7 to 2.4) in women, consistently across population. Risk factors accounted for a third of inequalities in CHD incidence; smoking was the major mediator in men, and High-Density-Lipoprotein (HDL) cholesterol in women. Conclusions Social inequalities in CHD are still widespread in Europe. Since the major determinants of inequalities followed geographical and gender-specific patterns, European-level interventions should be tailored across different European regions.