Elevated risk of myocardial infarction in very young immigrants from former Yugoslavia

We performed a hospital based case-control study to assess if the risk of myocardial infarction at a very young age (< or =40 years) was elevated in immigrants from the region of former Yugoslavia. Patients were classified as "exposed" if they or both their parents were born in former Yugoslavia. Consecutive myocardial infarction patients were recruited in the immediate post-infarction period from two Viennese hospitals over a 3.5-year period. Control patients free of myocardial infarction were frequency matched on age, gender, centre, and time in an approximate 1:2 ratio. Logistic regression was used for the assessment of an association between Yugoslavian descent and myocardial infarction. Overall, we recruited 102 myocardial infarction patients and 200 controls. The median age of infarction patients was 37.3 years. Yugoslavian descent was strongly associated with myocardial infarction (crude OR 7.3, 95% CI 3-18). This association was attenuated after multivariate adjustment (OR 3.9, 95% CI 1.2-13) but remained statistically significant. Using Miettinen's formula for population attributable risk, we calculated that between 15.3% (adjusted) and 17.8% (unadjusted) of myocardial infarction cases in very young patients could be attributable to immigrants from the studied region. In conclusion, we found that the risk of developing myocardial infarction at a young age is elevated in immigrants from the region of former Yugoslavia and their offspring. Even though residual confounding cannot be ruled out definitively, this risk seems to be independent of established cardiovascular risk factors.