Postmenopausal women with heart disease have three times the risk of developing heart failure if they also have diabetes, researchers report in Circulation: Journal of the American Heart Association.
In addition, diabetic women in the study who also had kidney disease or obesity, or whose diabetes was poorly controlled (fasting blood sugar levels above 300 mg/dL) had a risk of heart failure 6-10 times higher than that of women without diabetes.
Researchers analyzed records from 2,391 participants in the Heart and Estrogen/Progesterone Replacement Study (HERS) to determine risk factors for developing heart failure. Previous studies recognized some significant differences in heart failure between men and women. In men, for example, a heart attack more often precedes heart failure.
“In women, heart failure seems to happen often in the absence of a heart attack,” said Kirsten Bibbins-Domingo, M.D., Ph.D, lead author and an instructor in medicine, epidemiology, and biostatistics at the University of California, San Francisco. “Our goal was to find out what the risk factors were in women.”
Heart failure is a condition in which the heart can’t pump enough blood to the body’s other organs. Physicians diagnose about 550,000 new cases of congestive heart failure annually, and the condition kills nearly 53,000 Americans each year.
In the study, 237 of the women (average age 68.3) developed heart failure during an average of 6.3 years in HERS and its follow-up. The HERS trial tested the effectiveness of hormones in preventing a second heart attack in women who had already suffered one.
The study revealed nine health factors that identify postmenopausal women with coronary artery disease who have an increased risk of developing congestive heart failure. Diabetes was the most powerful predictor of heart failure. Women who had the disease on entering HERS were 3.1 times more likely to develop heart failure than women who did not. The risk from atrial fibrillation (abnormal rapid beats in the heart’s upper chambers) was nearly as great. Women with this abnormal heart rhythm were 2.9 times more likely to develop heart failure than women who did not have the condition.
The seven other factors are, in descending order of significance: two or more previous heart attacks, insufficient kidney function, hypertension, obesity, current smoking, and two heart disorders, left bundle branch block (a block in electrical impulses through the heart) and left ventricular hypertrophy.
“Lifestyle changes and/or medications can modify or prevent several of the nine risk factors,” Bibbins-Domingo said. “Physicians treating women with coronary disease should also focus on the risk factors for heart failure that are preventable or modifiable. These include controlling hypertension particularly, and also controlling blood sugar and obesity.”
Physicians long regarded heart failure as essentially a disease of men. “As with many types of heart disease, we are learning that heart failure is an equal-opportunity disease,” Bibbins-Domingo said. “There is a new realization among clinicians that heart failure, in particular, is also a woman’s disease.”