Altered hemodynamics during exercise in older essential hypertensive subjects

This study was designed to compare the resting and exercise hemodynamics of older adults with moderate hypertension with those of age-matched normotensive controls. Thirty-one hypertensive (20 men, 11 women; mean age, 63.9 ± 2.8 years) and 28 normotensive subjects (15 men, 13 women; mean age, 62.6 ± 2.4 years) were studied. There were no differences between the groups in terms of body weight, body composition, and maximal O₂ consumption (V̇(O₂)). At rest, there were differences in V̇(O₂), cardiac output, stroke volume, or heart rate between the two groups, although systolic (158 ± 13 vs 121 ± 12 mm Hg) and diastolic blood pressures (94 ± 7 vs 79 ± 8 mm Hg) were higher in the hypertensive subjects. The hypertensive subjects' elevated blood pressure at rest was the result of a higher total peripheral resistance. During exercise, the hypertensive subjects had a lower cardiac output and stroke volume, no difference in heart rate and V̇(O₂), higher systolic, diastolic, and mean blood pressures, and a higher total peripheral resistance compared with their normotensive peers. The results indicate that older hypertensive persons have an altered cardiovascular response to exercise as compared with age-matched normotensive subjects. The responses also indicate that older essential hypertensive persons do not undergo excessive myocardial demands during exercise of the intensity usually prescribed in rehabilitation programs.