Should diastolic and systolic blood pressure be considered for cardiovascular risk evaluation: a study in middle-aged men and women.

OBJECTIVES

The goal of this study was to evaluate the role of diastolic blood pressure (DBP) in cardiovascular mortality for different systolic blood pressure (SBP) levels in middle-aged men and women.

BACKGROUND

In middle-aged subjects it is unclear whether DBP, in addition to SBP, should be considered for risk evaluation.

METHODS

Subjects (77,023 men; 48,480 women) aged 40 to 70 years old, had no major cardiovascular disease, no antihypertensive treatment and were examined at the Centre d'Investigations Preventives et Cliniques between 1972 and 1988. Mortality was assessed for an 8- to 12-year period.

RESULTS

In both genders, cardiovascular mortality increased with the SBP level. In men and women with normal SBP levels, DBP did not influence cardiovascular mortality after adjustment for age and SBP. In men with systolic hypertension, a U-shaped curve relationship between cardiovascular mortality and DBP was observed, with the lowest mortality rates in the group with DBP 90 to 99 mm Hg. Compared with this group, age- and SBP-adjusted cardiovascular mortality was higher by 73% (p < 0.02) in the group with DBP <90 mm Hg and by 65% (p < 0.001) in the group with DBP > or =110 mm Hg. In women with systolic hypertension, however, DBP was positively correlated with cardiovascular mortality.

CONCLUSIONS

In middle-aged subjects, classification of cardiovascular risk according to DBP levels should take into account gender, especially when SBP levels are elevated. Men with systolic hypertension are at higher risk when their DBP is "normal" than when they present a mild to moderate increase in DBP. In women of the same age, however, systolic-diastolic hypertension represents a higher risk than isolated systolic hypertension.