Does obesity modify the effect of blood pressure on the risk of cardiovascular disease? A population-based cohort study of more than one million Swedish men.

Description

Previous investigations have suggested that the impact of elevated blood pressure on cardiovascular disease (CVD) was greater in lean persons than in obese individuals. This study examined this issue in a very large cohort (n=1,145,758) of Swedish men. During the course of the study, 65,611 new CVD events occurred, which included 6,799 myocardial infarctions and 8,827 strokes. Cox proportional hazards models were computed for 1 standard deviation increase in systolic and diastolic blood pressure according to body mass index categories (underweight, normal, overweight, obese). The strongest hazard ratios (HRs) of diastolic blood pressure with CVD (1.18), myocardial infarction (1.22), and stroke (1.13) were observed in the obese category. For systolic blood pressure, the highest HRs were with CVD (1.16) and stroke (1.29) in obese men but in the overweight category for myocardial infarction (1.19). Finally, significant interactions with body mass index for diastolic blood pressure in relation to CVD and for systolic blood pressure in relation to CVD and stroke were observed. Results of this large-scale study indicate that in contrast to previous studies, the impact of increasing blood pressure on CVD is independent from body mass index.