Primary Prevention of Coronary Heart Disease in Women through Diet and Lifestyle

Abstract

Many lifestyle-related risk factors for coronary heart disease have been identified, but little is known about their effect on the risk of disease when they are considered together. We followed 84,129 women participating in the Nurses' Health Study who were free of diagnosed cardiovascular disease, cancer, and diabetes at base line in 1980. Information on diet and lifestyle was updated periodically. During 14 years of follow-up, we documented 1128 major coronary events (296 deaths from coronary heart disease and 832 nonfatal infarctions). We defined subjects at low risk as those who were not currently smoking, had a body-mass index (the weight in kilograms divided by the square of the height in meters) under 25, consumed an average of at least half a drink of an alcoholic beverage per day, engaged in moderate-to-vigorous physical activity (which could include brisk walking) for at least half an hour per day, on average, and scored in the highest 40 percent of the cohort for consumption of a diet high in cereal fiber, marine n–3 fatty acids, and folate, with a high ratio of polyunsaturated to saturated fat, and low in trans fat and glycemic load, which reflects the extent to which diet raises blood glucose levels. Many of the factors were correlated, but each independently and significantly predicted risk, even after further adjustment for age, family history, presence or absence of diagnosed hypertension or diagnosed high cholesterol level, and menopausal status. Women in the low-risk category (who made up 3 percent of the population) had a relative risk of coronary events of 0.17 (95 percent confidence interval, 0.07 to 0.41) as compared with all the other women. Eighty-two percent of coronary events in the study cohort (95 percent confidence interval, 58 to 93 percent) could be attributed to lack of adherence to this low-risk pattern. Among women, adherence to lifestyle guidelines involving diet, exercise, and abstinence from smoking is associated with a very low risk of coronary heart disease.