TEMPORAL PATTERNS OF ANTIHYPERTENSIVE MEDICATION USE AMONG OLDER ADULTS, 1989 THROUGH 1992 - AN EFFECT OF THE MAJOR CLINICAL-TRIALS ON CLINICAL-PRACTICE

Objective.-To describe the changing patterns of antihypertensive medic ation use in the years immediately before and after the publication of the results of three major clinical trials of the treatment of hypert ension in older adults. Design.-In this cohort study, adults 65 years or older were examined annually on four occasions between June 1989 an d May 1992, and the use of antihypertensive medications was assessed b y inventory at each visit. The four visits defined the boundaries of t hree study periods. For each study period, participants receiving anti hypertensive therapy were either continuous users (n = 1667, 1643, and 1605, respectively) or starters (n = 157, 142, 120) of hypertensive t herapy. The large clinical trials that convincingly proved the efficac y and safety of low-dose diuretic therapy in older adults were publish ed during the latter parts of period 2 and the early parts of period 3 . Results.-Among starters, the proportion initiating therapy on diuret ics increased from 35.9% in period 2 to 47.5% in period 3, significant ly so among women (P=.04). The proportions initiating other drugs disp layed no significant trends. Among continuous users, the use of diuret ics, beta-blockers, and vasodilators generally decreased over the 3-ye ar period, while the use of calcium channel blockers and angiotensin-c onverting enzyme inhibitors increased significantly in each of the thr ee periods (P<.05). The decline of 2.7% in the prevalence of diuretic use in period 1 abated during period 2 (1.8% decline), and it slowed s ignificantly (P=.03) to almost a complete halt during period 3 (0.2% d ecline). The rate of increase in the use of calcium channel blockers s lowed significantly (P=.01) between period 1 (+6.7%) and period 3 (+2. 8%). Conclusions.-Although other factors such as cost may have been im portant, the temporal trends in antihypertensive drug therapy coincide d in time with and may have reflected in part the influence of the maj or clinical trials on the patterns of clinical practice.