Incidence of acute myocardial infarction in first and second generation minority groups: does the second generation converge towards the majority population?

BACKGROUND: Differences in acute myocardial infarction (AMI) incidence between ethnic minority and migrant groups (henceforth, minority groups) and the majority population have been reported. Health differences may converge towards the majority population over generations. We assessed whether AMI incidence differences between minority groups living in the Netherlands and the Dutch majority population exist, and whether the incidence converges towards the majority population over generations. METHODS: A nationwide register-based cohort study was conducted from 1997 to 2007. Using Cox Proportional Hazard Models AMI incidence differences between minorities and the majority population were estimated. When possible, analyses were stratified by generation. RESULTS: AMI incidence differences between minorities and the majority population depended on the country of origin, and often varied between minorities originating from the same geographical region. For example, among North African and Mediterranean minorities, incidence was higher in Turkish (Hazard Ratio (HR): 1.34; 95% Confidence Interval (95% CI): 1.28-1.41), but lower in Moroccans (HR: 0.46; 95% CI: 0.40-0.52) compared with the majority population. Most minorities had a similar or lower incidence than the majority population, which remained similar or converged towards the incidence of the majority population over generations. In contrast, among minorities from the former Dutch colonies (Suriname, Indonesia, Netherlands Antilles) beneficial intergenerational changes were observed. CONCLUSIONS: Health care professionals and policy makers should be aware of substantial AMI incidence differences between minority groups and the majority population, and the often unbeneficial change over generations. Future research should be cautious when clustering minority groups based on geographical region of the country of origin.