Downward trend in the risk of second myocardial infarction in Sweden, 1987–2007: breakdown by socioeconomic position, gender, and country of birth

Background Second myocardial infarction (SMI) is a significant health problem. There are no nationwide studies on SMI among foreign-born populations that include detailed information about country of birth. Design Nationwide cohort study of 331,748 men and 186,755 women aged 30–84, living in Sweden, and diagnosed with first myocardial infarction (FMI) between January 1987 and December 2007. Methods Trends in, and risk of, SMI after day 28 of FMI association with gender, educational level, and country of birth were analysed. A hazard ratio (HR) with a 95% confidence interval (CI) yielded a risk estimate of SMI among FMI patients based on the Cox proportional hazard model. Results Men had a higher risk of SMI than women (HR 1.14, 95% CI 1.12–1.55) with a downward trend over time, regardless of country of birth (p-trend