Comparison of coronary heart disease and stroke risks attributable to vascular risk factors: results from the PRIME study

Abstract

Background: Coronary heart disease (CHD) and stroke are the leading causes of death worldwide, although these diseases are preventable. In order to set priorities for public health policies, we sought to assess and compare within a single cohort, CHD and stroke population-attributable risks (PARs) for various cardiovascular risk factors. Methods: The PRIME study is a multicenter prospective population- based cohort of men living in France or Northern Ireland, aged 50-59 in 1991-93, and followed over 10 years to record CHD (coronary death, myocardial infarction, unstable angina) and stroke. Results: The sample comprised 9701 men, free of CHD and stroke at baseline. During the follow-up, 410 and 118 cases of CHD and stroke occurred. After adjustment for age, centre, antihypertensive and lipid-lowering treatments, alcohol consumption and other significant cardiovascular risk factors, PARs for CHD were 21.1% (high blood pressure), 14.8% (smoking), 11.1% (hypercholesterolemia), 9.8% (low HDL-cholesterol), 5.4% (obesity) and 1.9% (diabetes). The overall PAR for CHD, referring to the presence of at least one of the above detailed risk factors reached 71.2% (79.1% after exclusion of unstable angina). Adjusted PARs for stroke were 32.8% (high blood pressure), 15.9% (smoking) and 6.4% (diabetes), with no significant impact of the other risk factors. The overall PAR for stroke was 43.7% (44.6% for ischemic stroke). Conclusion(s): The impact of traditional cardiovascular risk factors on CHD and stroke are different. As prevention should primarily focus on factors exhibiting high PARs for both CHD and stroke, high blood pressure and smoking are the best targets for prevention.