Perceived health modifies the effect of biomedical risk factors in the prediction of acute myocardial infarction. An incident case–control study from northern Sweden

OBJECTIVES: To assess the importance of biomedical risk factors, social factors and self-reported health in the prediction of the first event of acute myocardial infarction (AMI) in an apparently healthy middle-aged population. DESIGN: An incident case-control study. SETTING: The study was nested within the Västerbotten Intervention Program and the Northern Sweden MONICA cohorts. SUBJECTS: The study consists of 78 AMI cases with two randomly selected controls per case from the same study cohorts. RESULTS: Significant odds ratios were found for history of diabetes, daily smoking, cholesterol, body-mass index, hypertension, lower education and perceived ill health. In multivariate logistic regression smoking, hypertension and cholesterol of > or =7.8 mmol L(-1) remained significant. An interaction was observed between number of biomedical risk factors and perceived health. CONCLUSIONS: Smoking, hypertension and hypercholesterolaemia explain a major share of incident AMI events in a Swedish middle-aged population. The study further illustrates that perceived ill health negatively modifies the impact of these risk factors.