SERUM-CHOLESTEROL, DIET, AND THE DECLINE IN CORONARY HEART-DISEASE MORTALITY

There has been a recent and dramatic decline in coronary heart disease death rates in the United States. The possible contribution of secular trends in serum cholesterol to this decline was examined by comparison of data from five epidemiologic studies: the Framingham Study, the Tecumseh Study, the Health Examination Survey, the Health and Nutrition Examination Survey, and the Lipid Research Clinics Program Prevalence Study. It appears that in the 1960s there was a modest decline in serum cholesterol levels (approximately 5 mg/dl in middle-aged adults). Although it is impossible to exclude methodologic variation as the main explanation for the observed trends, the contribution of dietary changes to this decline was also examined, by comparison of data from the Diet-Heart Study and the Lipid Research Clinics study. The decline in serum cholesterol was found to be consistent with the observed changes in dietary fat intake in the 1960s. When the potential impact of the decline in cholesterol levels on coronary heart disease death rates was assessed by use of a Framingham multivariate logistic risk function, it was found that a decline in cholesterol of 5 mg/dl would predict a 4.3% decline in 6-year coronary heart disease death rates in middle-aged men. © 1979.