Monday, August 31, 2009

New study helps explain why women have higher mortality rates after heart attack
by Kelly Shaw, DCRI Communications

A significant new database study found that women who have heart attacks are typically older and have more health complications and risk factors than men who have heart attacks. These findings partly explain why the study found that women were almost twice as likely to die within 30 days of having a heart attack compared to men.

The DCRI's Pamela Douglas, MD, is the senior author of the study, which analyzed patient data from 11 different randomized acute coronary syndrome (ACS) trials between 1993 and 2006. The findings were published in the August 26 issue of the Journal of the American Medical Association . The study reviewed data on more than 136,000 patients.

“Little has been known about why mortality rates differ between men and women following a heart attack, but this study shows that the cause can be attributed to the fundamentally different cardiovascular physiology of the sexes,” said Douglas.

Cardiovascular disease is the leading cause of death for both men and women, and outcomes have traditionally been worse for women. Previous studies on gender differences have had conflicting results. For this study, researchers wanted to identify if mortality rates for women were different for the three different types of ACS (unstable angina, STEMI heart attacks where coronary arteries are completely blocked, and NSTEMI heart attacks where the damage to the heart cannot be detected by an EKG).

Researchers found that women who were treated for STEMI (the most serious type of heart attack) were more likely to die within 30 days of treatment than men, but women had a lower risk of dying in the same time frame after being treated for unstable angina or NSTEMI.

Although the initial mortality rates were almost twice as high for women, once researchers adjusted for a variety of factors, the risk levels were similar for men and women. Researchers found that the female patients were more likely to have high blood pressure, high cholesterol, diabetes, and heart failure.

According to the study findings, the factors that seemed to increase the mortality risk for women the most were age, smoking, high blood pressure, and heart rate.

Douglas said the researchers hope the findings will help clinicians customize their treatments for men and women.

Other DCRI researchers involved with the study include Christopher Granger, MD: Matthew Roe, MD; Kristin Newby, MD, MS; Bob Harrington, MD; Richard Becker, MD; Laine Elliott, and Dianne Gallup. Rob Califf, MD, director of the DTMI, was also involved with the study.

Click here to read the full study.