Comparison of effects of exercise and diuretic on left ventricular geometry, mass, and insulin resistance in older hypertensive adults

Abstract

. Comparison of effects of exercise and diuretic on left ventricular geometry, mass, and insulin resistance in older hypertensive adults. Am J Physiol Regul Integr Comp Physiol 287: R360 -R368, 2004. First published April 29, 2004; 10.1152/ajpregu.00409.2003.-To compare the effects of exercise training and hydrochlorothiazide on left ventricular (LV) geometry and mass, blood pressure (BP), and hyperinsulinemia in older hypertensive adults, we studied 28 patients randomized either to a group (age 66.4 Ϯ 1.3 yr; n ϭ 16) that exercised or to a group (age 65.3 Ϯ 1.2 yr; n ϭ 12) that received hydrochlorothiazide for 6 mo. Endurance exercise training induced a 15% increase in peak aerobic power. The reduction in systolic BP was twofold greater with thiazide than with exercise (26.6 Ϯ 12.2 vs. 11.5 Ϯ 10.9 mmHg). Exercise and thiazide reduced LV wall thickness, LV mass index (14% in each group), and the LV wall thickness-to-radius ratio (h/r) similarly (exercise: before 0.48 Ϯ 0.2, after 0.42 Ϯ 0.01; thiazide: before 0.47 Ϯ 0.04, after 0.40 Ϯ 0.04; P ϭ 0.017). The reductions in systolic BP and h/r were correlated in the exercise group (r ϭ 0.70, P ϭ 0.005) but not in the thiazide group. Exercise training reduced glucose-stimulated hyperinsulinemia (before: 13.65 Ϯ 2.6 vs. 9.84 Ϯ 1.5 mU ⅐ ml Ϫ1 ⅐ min; P ϭ 0.04) and insulin resistance. Thiazide did not affect plasma insulin levels. The results suggest that although exercise is less effective in reducing systolic BP than thiazide, it can induce regression of LV hypertrophy similar in magnitude to thiazide. Unlike hydrochlorothiazide, exercise training can improve insulin resistance and aerobic capacity in older hypertensive people. left ventricular remodeling; blood pressure; hyperinsulinemia; fitness SYSTOLIC HYPERTENSION is a common disorder in older men and women. It is a major but modifiable risk factor for cardiovascular morbidity and mortality in old age (3,14). Left ventricular (LV) hypertrophy (LVH), commonly observed in hypertension, is a powerful predictor of cardiovascular morbidity and mortality independent of the level of blood pressure (BP) in hypertensive adults (2,14,29). Reduction of systolic BP can reduce the risk of stroke and heart failure in hypertensive older individuals (2, 4). Furthermore, regression of LVH is likely to reduce cardiovascular risks in hypertension (40).Endurance exercise training has been recommended for management of hypertension because it is effective in reducing BP (16,19,46,47). Recent studies showed that exercise training may also reduce LV concentric remodeling and LVH (18, 27, 51). As endurance exercise training improves hyperinsulinemia and insulin resistance (20,23,39), it is plausible that this adaptation may play a role in regression of LV remodeling and LVH because insulin is a stimulus for the development of cardiac hypertrophy (30, 36, 37). It is not clear, however, whether exercise can induce regression of LV remodeling in older adults or whether it is as effective as antihypertensive medications in reducing LV mass ...

Cardiac benefits of exercise training in aging spontaneously hypertensive rats

“…Along this line of thought, low-intensity exercise delays the onset of heart failure in aging SHR [24,25]. Clinical studies have also shown that endurance exercise training is accompanied by a reduction in left ventricle hypertrophy in elderly hypertensive patients receiving antihypertensive treatment (or not) [10,14,26]. This reduction was similar to that observed with a diuretic treatment [14].…”

“…Experimental and clinical studies have demonstrated that acute and chronic exercise (static, aerobic endurance or resistance) have beneficial effects on BP levels [8][9][10][11][12]. This benefit is accompanied by a regression of cardiovascular adjustments that occurs with hypertension [9,10,[13][14][15]. However, most of these studies have been performed in young or middle-aged individuals or animals and have evaluated the effects of short-term and long-term exercise training in the progression of hypertension; few studies have explored whether or not this benefit can be extended to elderly hypertensive animals.…”

Acute cardiac functional and mechanical responses to isometric exercise in prehypertensive males

“…Indeed, Rinder et al. (2004) demonstrated a significant correlation between reductions in systolic blood pressure and reduced relative wall thickness and reported an increase in stroke volume, cardiac output, and LV ejection fraction in their exercise training group. Other lifestyle interventions, such as low sodium diets have demonstrated significantly improved LV diastolic function with significantly reduced ABP in hypertensive heart failure patients (Hummel et al.…”

“…These favorable LV remodeling responses to acute IE are similar to those reported in patients with hypertension following a program of aerobic exercise training or prescribed diuretics (Rinder et al. 2004). A single IE training session was associated with improved global longitudinal, circumferential strain and strain rate and apical radial strain as well as increased LV twist and untwist.…”

Cardiac Effects of Exercise Training in Hypertension

“…e effects of exercise training on cardiac remodeling in hypertensive human subjects have been reviewed elsewhere [63] and have shown equivocal results with some studies showing no change in le ventricular mass [64][65][66][67][68][69], a decrease in le ventricular mass/le ventricular mass index [64,[70][71][72][73][74], and an increase in le ventricular mass/le ventricular mass index [5,66]. e majority of these studies showed that systolic and diastolic blood pressure was reduced following exercise, and imaging was most oen measured with M-mode and 2D guided echocardiography.…”