EXERCISE BLOOD-PRESSURE PREDICTS CARDIOVASCULAR MORTALITY IN MIDDLE-AGED MEN

The outcome of 1999 apparently healthy men aged 40 to 59 years investi gated from 1972 through 1975 was ascertained after 16 years to determi ne whether systolic blood pressure measured with subjects in the sitti ng position during a bicycle ergometer exercise test adds prognostic i nformation on cardiovascular mortality beyond that of casual blood pre ssure measured after 5 minutes of supine rest. During a total follow-u p of 31 984 patient years, 278 patients died, 150 from cardiovascular causes. Casual blood pressure and pulse pressure as well as peak exerc ise systolic blood pressure during 6 minutes on the starting workload of 600 kpm/min (approximately 100 W, 5880 J/min) were all related to c ardiovascular mortality. The relative risk (RR) of dying from cardiova scular causes associated with an increment of 48.5 mm Hg (=2 SD) in sy stolic blood pressure at 600 kilopondmeter (kpm)/min was significant ( RR=1.5, 95% confidence interval [CI]=1.1-2.3, P=.040) even when adjust ing for a large number of variables measured in the present study, inc luding age, exercise capacity, smoking habits, and casual blood pressu res. The influence of blood pressure at 600 kpm/min was so strong that the predictive value of resting casual blood pressures became nonsign ificant when these were analyzed as continuous variables also includin g exercise blood pressure as a covariate. However, the maximal systoli c blood pressure during the exercise test was unrelated to cardiovascu lar mortality. Among the 520 men with resting systolic blood pressure of 140 mm Hg or greater, those 304 who increased their systolic blood pressure to 200 mm Hg or greater during 6 minutes of the starting exer cise workload of 600 kpm/min had a 16-year cardiovascular death rate o f 16.1% compared with 6.0% among those with a systolic blood pressure less than 200 mm Hg at 600 kpm/min (n=216, RR=2.0, 95% Cl=1.1-4.0, P=. 025). The cardiovascular death rate was also 6.0% among those who were normotensive at rest (n=1479). Thus, an early rise of systolic blood pressure during exercise adds prognostic information on cardiovascular mortality among otherwise healthy middle-aged men with mildly elevate d casual blood pressure.