Archief Roodbont

Systolic Blood Pressure Still the Best Predictor of Cardiovascular Risk in Men

An evaluation of over 50,000 men who participated in the Physicians' Health Study (PHS) has shown that SBP alone is a consistent predictor of cardiovascular death in men of all ages. This finding is consistent with the "continuing emphasis on the clinical use of SBP to predict the risk of incident cardiovascular disease," say Thomas S. Bowman, MD, MPH (Massachusetts Veterans Affairs Epidemiology, Research, and Information Center, Boston) and colleagues^[15] in the American Journal of Hypertension.

In a study funded by the US National Institutes of Health, Dr. Bowman's team studied 53,528 male physicians, mean age 53 years, who provided information about BP to the PHS in 1983. In this population, mean SBP was 124.8 mm Hg and mean DBP was 78.0 mm Hg. Subjects had no previous or current treatment for hypertension or history of any serious disease, including myocardial infarction, stroke/TIA, cancer, or gastrointestinal or liver disease. Other information was obtained through questionnaires. The men were followed for a median of 5.7 years. Information about deaths was obtained from the National Death Index and the cause of death derived from international classifications of diseases.

During follow-up, 459 men died from cardiovascular causes. For each 10-mm Hg increase in SBP, the relative risks, adjusted for age, tobacco use, BMI, diabetes, alcohol intake, exercise, and aspirin or multivitamin use, were 1.46, 1.43, 1.24, and 1.13 in the age groups 39-49, 50-59, 60-69, and 70-84 years, respectively. Similarly, adjusted relative risks for each 10-mm Hg increase in DBP were 1.25, 1.20, 1.28, and 1.07, respectively. Compared with SBP, pulse pressure and mean arterial pressure were not consistent predictors across age ranges, and combining SBP with any other parameter did not improve the model compared with using SBP alone in any age group (all P > .05).

Dr. Bowman and colleagues stress that "although DBP, pulse pressure and mean arterial pressure were also associated with elevated risk, none of these other blood pressure parameters was superior in determining risk or enhanced multivariable models that already contained SBP." They believe that although men already having hypertension were excluded at baseline, because some participants may have started taking antihypertensive medications during the study, the association between BP and cardiovascular disease death may have been underestimated. They also note that the PHS participants were healthy male physicians, which may affect application of the study findings to other populations, although "we have no reason to believe that the biological mechanism by which blood pressure may be associated with cardiovascular disease death is unique to our study population," they contend.