Background: During the 1980s data became available from randomized trials concerning the clear benefits of treating hypertension in the elderly. In three large communities, we examined the impact of these findings on rates of treatment, use of specific antihypertensive drugs, and rates of elevated blood pressure as well as distributions of levels.
Methods: In 1981 the National Institute on Aging initiated population-based cohort studies in the residents of three communities who were 65 years and older. East Boston, Mass; Washington and Iowa counties, Iowa; and New Haven, Conn. Participation rates ranged from 80% to 85% across sites with 10,294 community-dwelling participants in the combined cohorts. Baseline evaluation included inhome blood pressure assessment and medication inventory. Repeated in-home evaluations occurred 3 and 6 years after baseline and follow-up rates ranged from 71% to 88%.
Results: Use of antihypertensive drugs increased over time in all three communities: the age- and sex-adjusted rates of use were between 14% and 32% higher in 1988 and 1989 relative to 1982 and 1983. Parallel declines in the use of thiazide diuretics occurred in all three populations along with large increases in the use of angiotensin-converting enzyme inhibitors and calcium channel blockers. In East Boston and New Haven mean systolic blood pressure decreased substantially over time and the prevalence of elevated systolic pressure (> or = 160 mmHg) decreased overall as well as by age and sex. In Iowa the mean levels of systolic blood pressure were lowest at baseline and increased slightly.
Conclusions: The reported evidence about the benefits of treatment for hypertension in the elderly was followed by substantial increases in treatment rates. The use of drugs with proven efficacy declined while the use of newer agents with theoretical advantages, not yet tested in clinical trials of mortality, increased. In the United States, the ongoing therapeutic efforts to lower elevated blood pressure in elderly populations may be contributing to the continuing decline in cardiovascular and stroke mortality.