Usefulness of cardiorespiratory fitness as a predictor of all-cause and cardiovascular disease mortality in men with systemic hypertension

There is an inverse gradient of mortality across levels of cardiorespiratory fitness in healthy adults; however, the association of fitness to mortality in persons with comorbidities such as hypertension is not fully understood. This study quantifies the relation of cardiorespiratory fitness to all-cause mortality and cardiovascular disease (CVD) mortality in hypertensive men. In this observational cohort study, we calculated death rates for low, moderate, and high fitness categories in normotensive (n = 15,726) and hypertensive (n = 3,184) men, and in men without a history of hypertension but with elevated blood pressure (BP) (systolic BP greater than or equal to 140 or diastolic BP greater than or equal to 90 mm Hg) at baseline (n = 3,257). The participants were 22,167 men (average age 42.6 +/- 9.2 years [mean SD]) who underwent a medical examination that included a maximal exercise test during 1970 to 1993, with mortality follow-up to December 31, 1994. We identified 628 deaths (188 from CVD) during 224,173 man-years of observation. There was an inverse linear trend across fitness groups for all-cause and CVD mortality. The relative risk (95% confidence interval [CI]), using the low fitness group as reference, for all-cause mortality in hypertensive men was 0.45 (95% CI 0.31 to 0.65) and 0.42 (95% Cl 0.27 to 0.66) for moderate and high fitness groups, respectively, and in men with elevated BP, 0.49 (95% Cl 0.34 to 0.70) and 0.44 (95% Cl 0.29 to 0.68) for moderate and high fitness groups, respectively. The pattern of results was similar for CVD mortality. There was an inverse linear relation between fitness and death rate for all-cause mortality in both the uncontrolled and controlled hypertensive groups. This study provides evidence that moderate to high levels of cardiorespiratory fitness provide protection against all-cause and CVD mortality in hypertensive men and men without a history of hypertension but with elevated BP at examination. (C) 2001 by Excerpta Medico, Inc.