Exercise Capacity and All-Cause Mortality in Male Veterans With Hypertension Aged ≥70 Years

Abstract

H ypertension represents a major public health problem, affecting more than 1 billion persons worldwide, a number that is expected to increase to ≈1.5 billion during the next decade. 1 The prevalence of hypertension rises with increasing age; in fact, the majority of elderly individuals have high blood pressure (BP).2 On the basis of Framingham data, the probability of an individual with normal BP at 55 years of age to become hypertensive during the next 2 decades is ≈90%, 3 with 7.6 million premature deaths (≈13.5% of the total global mortality) attributed to high BP. 4 Given that advances in medical therapy and living conditions have prolonged life expectancy, the number of older individuals is expected to double over the next 2 decades, with 1 of 5 individuals being ≥65 years by 2030.5 Thus, the prevalence of hypertension is expected to continue to be a major public health problem worldwide.Although cardiorespiratory fitness (CRF) is influenced by many factors, regular physical activity develops CRF.6,7 Low-tomoderate intensity exercise training has been shown to improve CRF significantly in middle-aged and older hypertensive veterans.8 Increased physical activity leading to improved CRF status is now a part of standard lifestyle recommendations for hypertensive individuals by itself or as an adjunct to pharmaceutical therapy to manage hypertension and lower mortality risk. 9Increased CRF is associated with a lower rate of progression to hypertension 10 and a lower mortality risk in relatively healthy individuals and those with comorbidities, including hypertension.11-15 Significant reductions is mortality risk are noted in middle-aged individuals when peak exercise capacity exceeds ≈5 to 7 metabolic equivalents (METs).11-15 However, it is not known whether this fitness threshold applies to the elderly. The proportion of individuals achieving the minimum amount of recommended physical activity decreases with age and is estimated to be as low as 15.9% in adults ≥65 years of age.16 Furthermore, chronic health conditions known to be associated with aging might limit the ability of older individuals to exercise or to achieve an exercise capacity necessary for health benefits. Moreover, medical costs increase substantially with aging, which coupled with life prolongation, dramatically increase healthcare costs during subsequent decades.9 Because regular physical activity is associated with better health Abstract-Aging, even in otherwise healthy subjects, is associated with declines in muscle mass, strength, and aerobic capacity. Older individuals respond favorably to exercise, suggesting that physical inactivity plays an important role in age-related functional decline. Conversely, physical activity and improved exercise capacity are associated with lower mortality risk in hypertensive individuals. However, the effect of exercise capacity in older hypertensive individuals has not been investigated extensively. A total of 2153 men with hypertension, aged ≥70 years (mean, 75±4) from the Washington, DC, and Palo Alto...

Importance of Assessing Cardiorespiratory Fitness in Clinical Practice: A Case for Fitness as a Clinical Vital Sign: A Scientific Statement From the American Heart Association

“…The risk reduction per 1-MET increase in measured CRF was 17% for fatal CVD and 10% for nonfatal CVD in men and 5% for fatal CVD and 23% for nonfatal CVD in women. Comparable findings have been reported in ongoing follow-up studies from cohorts including the Veterans Exercise Testing Study, [17][18][19]22 the Aerobics Center Longitudinal Study (ACLS), 2,5,13,20,51 and the Henry Ford Exercise Testing Project. [52][53][54] Importantly, the overall discriminative ability of CRF in these studies is comparable to that normally obtained in widely used risk models, such as the Framingham risk score and European SCORE (Systematic Coronary Risk Evaluation) algorithm.…”

“…This observation has been made in healthy men and women, those with suspected or known CVD, and those with comorbid conditions, including obesity, T2DM, hypertension, and lipid abnormalities. [12][13][14][15][16][17][18][19][20][21][22][23] In a growing number of studies, CRF has been demonstrated to be a more powerful predictor of mortality risk than traditional risk factors such as hypertension, smoking, obesity, hyperlipidemia, and T2DM. In addition, CRF has been shown to be a more powerful predictor of risk than other exercise test variables, including ST-segment depression, symptoms, and hemodynamic responses.…”

“…These follow-up studies included subjects with and without CVD, T2DM, obesity, and lipid abnormalities and of varying ethnicities, as well as women who were apparently healthy at the time of their fitness evaluation. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] Gulati et al 23 suggested that the strength of exercise capacity in predicting risk of mortality was even greater among women than men, demonstrating a 17% lower risk for every 1-MET increase in CRF. Similarly, Nes et al 38 reported a 21% lower risk for every 1-MET increase in CRF for both sexes in a large healthy population followed up for an average of 24 years.…”

“…12,13,[16][17][18][19][20][21]24 Despite these observations, the importance of CRF in the risk paradigm has historically received less attention from health professionals and CVD specialists. Moreover, when an exercise test is performed, there has been the tendency to focus on ischemic ST-segment displacement and the potential need for coronary revascularization without considering the prognostic value of CRF.…”

“…8,[12][13][14][15][16][17][18][19][82][83][84] However, although the evidence that CRF is inversely associated with mortality is strong and convincing, it does not necessarily mean that CRF directly enhances CVD mortality risk prediction. For CRF to truly be a novel risk marker, it must improve risk prediction beyond traditional markers.…”