The Marked Decline in Coronary Heart Disease Mortality Rates in the United States, 1968-1981; Summary of Findings and Possible Explanations

Abstract

During the years 1940–1967, age-adjusted mortality rates from coronary heart disease (CHD) rose in the USA by 14.1 % for all persons aged 35–74. This upward trend was recorded for white men, black men, and black women, but not for white women. From 1968 to 1981 (year of latest record), the trend in the preceding period was reversed, i.e., CHD death rates decreased steadily, at a rate averaging about 3% per year. This downward trend has involved all age-sex-color groups in the adult population and all regions of the country. It has encompassed both main categories of CHD, i.e., acute myocardial infarction (AMI) and chronic ischemic heart disease (CIHD), the former more prominently than the latter, especially among adults aged 35–64. The US decline in CHD mortality rates is greater – absolutely and relatively – than that of any other country. US death rates from stroke have also fallen markedly over these years, so that death rates from the major cardiovascular diseases (CVD) and all causes also fell substantially, with savings of hundreds of thousands of people from premature death since 1968. Responding to vigorous development in the USA over the last 25 years of public policy and strategy for the prevention and control of the coronary epidemic, tens of millions of Americans have made changes in eating habits resulting in lower population mean intake of total fat, saturated fat, cholesterol; increased intake of polyunsaturated fats; decreased mean levels of serum cholesterol and rates of hypercholesterolemia. Prevalence rates of cigarette smoking among adults have also decreased markedly. Tens of millions have taken up leisure time exercise. All these changes have occurred more among the more educated-affluent than among the less educated-affluent. Over the last decade the proportion of persons with hypertension whose hypertension was detected, treated, and controlled has risen from 10 to 15% to embrace a majority of hypertensives. It is a reasonable inference that these mass changes in life-styles and life-style-related major CHD risk factors have contributed importantly to the large sustained declines in CHD, CVD, and all causes death rates in the USA. Concordant Stamler with this inference are data sets indicating greater declines in CHD mortality among the more educated-affluent strata than among the general population (matched for age-sex-color), in keeping with the greater changes in life-styles among the more educated-affluent, e.g., as exemplified by findings for physicians. Many developments in medical-surgical care (emergency, acute, long-term) for patients with clinical CHD of various types – and the expanding application of these developments, especially over the last decade – have in all likelihood also contributed to both the sustained nature and substantial extent of the decline in CHD mortality in the USA.