Myocardial infarction in second-generation immigrants compared to native-born Swedes in the total population of Sweden

Background and aims: Environmental and genetic factors predispose to cardiovascular disease. Some first-generation immigrants have a higher cardiovascular risk in Sweden, while less is known about second-generation immigrants. We aimed to analyze the risk of acute myocardial infarction (AMI) among second-generation immigrants in Sweden.

Methods: We included all individuals 18 years of age and older in Sweden, n = 4,580,967. AMI was defined as at least one registered diagnosis in the National Patient Register between January 1, 1998, and December 31, 2018. Cox regression analysis was used to estimate the relative risk (hazard ratio = HR) with 99 % confidence interval (CI) of incident AMI with adjustments made for age, sociodemographics, and comorbidities, and also subdivided into two age groups, i.e., 18-54 years and ≥55 years.

Results: A total of 158,815 AMI events were registered. Fully adjusted models showed HRs (99 % CI) in second-generation immigrants for men 1.05 (1.01-1.08), and for women 0.99 (0.94-1.05). A marginally higher MI risk was found only among men with parents from the Nordic countries in the fully adjusted model, HR 1.05 (1.01-1.10), and a lower risk only among women with parents from Asian countries, HR 0.47 (0.30-0.75). No significant overall differences in AMI risk were seen in older and younger second-generation immigrants.

Conclusions: The overall risk of AMI was similar for most groups of men and women with foreign-born parents compared to native-born Swedes. Our findings suggest that environmental factors may be more important than genetic factors, but further studies are needed to quantify these risks concerning AMI.