MONDAY, Dec. 8, 2008 (HealthDay News) -- Women who suffer the most severe form of heart attack are twice as likely as men to die in the hospital, a new study finds.
The study of more than 78,000 people treated for heart attacks at 420 U.S. hospitals between 2001 and 2006 found the same overall in-hospital death rate for men and women.
But 10.2 percent of women with a STEMI heart attack died, compared to 5.5 percent of men with the same diagnosis, said the report in the Dec. 9 issue of the journal Circulation.
"We believe that a part of it may be related to the fact that women are undertreated," said study lead author Dr. Hani Jneid, an assistant professor of cardiovascular medicine at Baylor College of Medicine in Houston. "There is evidence across the board of undertreatment."
"We obviously could not assess the appropriateness of the treatments," Jneid added. "But the results point to the fact that there might be some sex-related disparity in treatment that needs to be addressed by physicians."
STEMI is short for ST-elevation myocardial infarction, a name derived from the heartbeat pattern seen on an electrocardiogram. A STEMI heart attack usually is caused by complete blockage of a coronary artery, which means that more heart muscle dies than if there is only partial blockage.
While in theory "there is no intrinsic reason why there should be a difference" in survival rates between the sexes, there are several possible explanations, said Dr. Gregg C. Fonarow, a professor of cardiovascular medicine at the University of California, Los Angeles, and an author of the report. Those explanations may start with the symptoms reported by people having heart attacks and then go on to the treatment they receive, he said.
"Women when presenting with a heart attack tend to be older and have other comorbid conditions [health problems]," Fonarow said. "But even when we adjusted for that, we found a 12 percent difference."
Also, "women present more atypically," he said. "They are less likely to have sternal chest pain or pressure, just general symptoms like shortness of breath or other symptoms that are non-specific."
But there clearly was a difference in the treatment given men and women, the study found. Women were 14 percent less likely to receive early aspirin, 10 percent less likely to be given beta blocker drugs, 25 percent less likely to receive reperfusion therapy to restore blood flow, and 13 percent less likely to have artery-opening angioplasty within 90 minutes of arrival at the hospital.
The American Heart Association has started a program called "Mission: Lifeline" that's designed to educate people about the symptoms of a heart attack so they can seek treatment quickly and also "enable hospitals to make quicker diagnoses," Fonarow said. "These kinds of quality-improvement programs can lead physicians, emergency room attendants and paramedics to close the gap and eventually eliminate sex-related differences."
Some basic biological differences between the sexes might be partially responsible for the discrepancy in survival, said Dr. Laura Wexler, senior associate dean at the University of Cincinnati College of Medicine, and another author of the report.
"For women ages 50 to 60, I wonder whether the biology of a heart attack may be different," she said. "The question is whether menopause enhances the severity of heart attacks."
The incidence of heart attack in such perimenopausal women is lower, Wexler said, "but when they do get it, the mortality rate is higher."
Still, Wexler said, "I think there are impediments to the diagnosis of coronary disease in women, including, but not exclusively, some lack of appreciation in some sectors of the importance of coronary disease in women."
For descriptions about the various kinds of heart attacks and what should be done about them, visit the American Heart Association.