Heart Attacks and Women: Good News and Bad News

Here's a good news bad news story. In the past two decades heart attacks have become more common in middle-aged women (bad news), but since 1994, the risk of women dying from heart attacks has decreased (good news). These findings, from two studies, were just published in the Archives of Internal Medicine.

To track heart attack rates, researchers, led by Amytis Towfighi, M.D, of the University of Southern California, Los Angeles, analyzed data from over 8,000 U.S. adults between the ages of 35 and 54 who participated in the National Health and Nutrition Examination Surveys between 1988 to 1994 and 1999 to 2004.

In both study periods, men had more heart attacks than women in the same age group (35 - 54). But while heart attacks decreased in prevalence among men in recent years, they increased among women (2.5 percent of men and 0.7 percent of women reported a history of heart attack in 1988-1994, whereas 2.2 percent of men and 1 percent of women did so in 1999-2004).

The researchers also looked at participants 10-year coronary risk scores--a measurement of heart disease risk that includes factors such as age, cholesterol levels, blood pressure and smoking history. Between the two time periods, the average risk score showed an improving trend among men -- their total cholesterol levels remained stable, high-density lipoprotein (HDL or "good" cholesterol) levels and systolic (top number) blood pressure levels improved and smoking levels declined. But with women, the only risk factor that improved was HDL levels. Diabetes prevalence increased among both men and women, likely due to insulin resistance and the obesity epidemic in both sexes.
To determine the rate of death by heart attack, Viola Vaccarino, M.D., Ph.D., of Emory University School of Medicine, and colleagues analyzed data collected between 1994 and 2006, from 916,380 heart attack patients through the National Registry of Myocardial Infarction.

The researchers found that in-hospital death rates decreased among all patients in the time studied, but decreased more markedly in women than in men. While female heart attack patients under 55 showed a 52.9 percent reduction in the risk of death, men in the same age group showed a 33.3 percent decrease.

The authors chalk up the sex difference in the decrease of death rates to a better recognition that heart disease affects women as well as men. "A large part (93 percent) of this sharper decrease in mortality ... was because the risk status of women on admission improved compared with that of men," they write. By the same token, the increase in the rate of heart attacks among women may be explained in part, by detection of more non-fatal heart attacks. In other words, women don't have die before physicians discover heart damage. Recognizing coronary disease in women while it's still treatable has meant the difference between life and death for many.