Age and antihypertensive drugs (hydrochlorothiazide, bendroflumethiazide, nadolol and captopril).

Three double-blind Veterans Administration Cooperative Studies are reviewed to determine age-related changes in response to antihypertensive agents. In the first study 312 patients received hydrochlorothiazide titrated from 25 to 100 mg twice daily to lower diastolic blood pressure (BP) to less than 90 mm Hg. Of 121 patients aged 55 to 65 the decrease in BP averaged -21.8/-12.9 mm Hg, while in the 191 patients younger than 55 the reduction averaged -15.7/-11.5 mm Hg (p less than 0.001; p = 0.048, respectively). Both systolic and diastolic BP reductions averaged significantly more in older whites; in older blacks it was systolic BP only. An additional 298 patients received titrated doses of propranolol alone. In this group there were no significant differences in BP response between younger patients and patients aged 55 to 65 except in the subgroup of white patients older than 60, in whom the systolic reduction was significantly less than in the younger patients. In a second study of bendroflumethiazide alone and with nadolol, systolic BP decreased more in older than in younger patients but there was no age-related reduction with nadolol alone. In the third trial captopril was first given alone and later with hydrochlorothiazide. There were no age-related differences with captopril alone, but after the addition of hydrochlorothiazide there was a trend toward a greater antihypertensive response in the patients aged 55 to 69. Thus, responsiveness of older patients varies with the type of antihypertensive drug. Age appears to increase the antihypertensive response to thiazide diuretics but not to beta-adrenergic blocking drugs or to captopril.