The design was that of a retrospective study of successive cohorts of a well-defined and well-documented elderly population for the purpose of identifying and explaining trends in congestive heart failure (CHF) incidence, survival, comorbidities and health services utilization during the 25-year period 1970-1994. The study sample consisted of two successive period cohorts of elderly people, identified for each of two five-year periods, 1970-1974 and 1990-94. The study tested the following hypotheses: 1) incidence of CHF had decreased among the younger old (65-74 years of age); 2) incidence of CHF had increased among the older old (75 years of age or above); 3) one-year survival time had increased following onset of incident CHF; and 4) prevalence of hypertension had decreased and prevalence of myocardial infarction and other manifestations of coronary artery disease increased among incident cases of CHF.