Sharp Declines
in Heart Disease in Women
Decreases
Attributed to Improved Diets, Quitting Smoking, and Other Lifestyle Changes
Researchers at HSPH and Brigham and Women's Hospital (BWH) found a 31 percent decline in coronary heart disease (CHD) in a group of nearly 86,000 women followed over 14 years. A thorough analysis of the group's diet, lifestyle, and medical history indicated that most of this improvement is due to improving diets, quitting smoking, and using postmenopausal hormones.
During the course of the study, participants' consumption of red meat dropped by nearly 40 percent, intake of trans fats dropped by more than 30 percent, and use of high-fat dairy products decreased by more than 40 percent. These changes were complemented by increases in consumption of cereal fiber, folic acid, and fish. Simultaneously, the smoking rate declined by 41 percent and the proportion of postmenopausal women using hormone therapy increased almost two-fold.
However, these gains achieved through healthy behaviors were somewhat offset by gains in weight: the number of overweight participants increased by 38 percent.
"The decline in heart disease may have been even greater if not for the increase in obesity, which elevates risk for this disease," said Frank Hu, assistant professor in the Department of Nutrition and lead author.
The report, "Trends in the Incidence of Coronary Heart Disease, Diet, and Lifestyle Factors in Women," published in the August 24 issue of the New England Journal of Medicine (NEJM), follows and extends related conclusions about the effects of diet and lifestyles on CHD published in July in NEJM by some of the same authors.
The earlier report, "Primary Prevention of Coronary Heart Disease in Women Through Diet and Lifestyle," found that women could substantially reduce their risk of CHD by adhering to a set of dietary and behavioral guidelines.
Hu, who was also a coauthor of the July report, says: "Taken together, these studies give strong support to the theories that much of heart disease can be prevented through changes in diet and lifestyle. This newest study shows that a person's risk can drop very quickly by improving his/her diet and by quitting smoking."
Regarding the protective effect of postmenopausal hormone use, Hu says: "Our findings are compatible with previously published results that show a long-term reduction in risk of heart disease among women taking hormones. However, there is some evidence of increased risk for breast cancer and even a short term increased risk of heart disease for those who already have the disease when they begin hormone therapy."
Women considering postmenopausal hormone therapy should talk to their physicians and weigh the potential benefits against possible harmful effects, advise the researchers.
The participants were part of the BWH-based Nurses' Health Study and were free from cardiovascular disease and cancer when they entered the study. Their diet and lifestyle information was updated periodically, and after 14 years of follow-up, 1,304 cases of coronary heart disease were found in the group.
