Time trends in the prevalence of atherosclerosis: a population-based autopsy study.

ABSTRACT

PURPOSE: Mortality from coronary heart disease is declining but little is known about trends in the prevalence of atherosclerosis. Autopsy rates in Olmsted County, Minnesota, are higher than the national average, offering an opportunity to address this matter. In this study, we determined the prevalence of anatomic coronary disease among autopsied Olmsted County residents and examined the generalizability of these findings. SUBJECTS AND METHODS: Reports of the 2,562 autopsies performed between 1979 and 1994 on Olmsted County residents > or =20 years of age were reviewed for the presence of coronary disease. RESULTS: Among autopsied decedents less than 60 years old at death and among coroner's cases, the prevalence of anatomic coronary disease declined with time (P for trend = 0.05); no trend was detected among older persons or noncoroner's cases. By logistic regression analysis, the crude odds ratio ([OR] per 5 years) for the association between time and anatomic coronary disease was 0.94 (95% confidence interval [CI] 0.86 to 1.03; P = 0.18]. Age, sex, and antemortem diagnosis of heart disease were also strongly related to the presence of disease. After adjustment for sex and antemortem diagnosis of heart disease, the prevalence of anatomic coronary disease decreased more in younger people than in older people (age 40 years OR 0.43 [95% CI 0.24 to 0.80]; age 60 years OR 0.62 [95% CI 0.45 to 0.87]; age 80 years OR 0.89 [95% CI 0.64 to 1.23]). CONCLUSION: The prevalence of anatomic coronary disease at autopsy decreased between 1979 and 1994, particularly among younger people, supporting the notion that the burden of coronary disease has shifted toward the elderly. These results suggest that the decreased incidence of coronary artery disease has contributed to the recent decrease in coronary mortality, particularly among younger people.