Unusual fatigue and sleeplessness might be early warning signs of a heart attack in women, a study suggests.
The study, published Monday in the American Heart Association journal Circulation, surveyed 515 women who had heart attacks and found that 95 percent had such symptoms as much as a month before they were stricken.
Chest pains can be an early indicator of a heart attack, but 43 percent of the women in the study said they never experienced chest discomfort, even during the attack, said researcher Jean McSweeney.
The study is one of the first comprehensive examinations of women's heart attack symptoms, which experts are coming to realize are quite different and often more subtle than those experienced by men.
The women in the study, with an average age of 66, were diagnosed with a heart attack and discharged from five hospitals in Arkansas, North Carolina and Ohio within the previous four to six months.
The most frequently reported symptoms were unusual fatigue (71 percent); sleep disturbance (48 percent); and shortness of breath (42 percent). Fewer than 30 percent of the women reported having any chest pain or discomfort before the heart attack.
The women had more than just ordinary fatigue and sleeplessness.
"The fatigue is unexplained and unusual. They are more tired at the end of the day than they usually are. For some, it's so severe that they can't make a bed without resting as they tuck the sheets. It interferes with their normal activities," said McSweeney, lead author of the study and a professor in the College of Nursing at the University of Arkansas for Medical Sciences in Little Rock.
"Increasingly, it is evident that women's symptoms (of a heart attack) are not as predictable as men's," said Patricia Grady, director of the National Institute of Nursing Research, which paid for the study.
The classic symptoms in men include pressure or pain in the center of the chest that radiates down the arm or neck.
Those women who did experience chest discomfort before the heart attack described it in terms of aching, tightness or pressure, rather than pain, the researchers said. Yet most medical professionals continue to consider chest pain as the most important symptom of acute myocardial infarction in both women and men.
Dr. Nieca Goldberg, a cardiologist at Lenox Hospital in New York, said the study could change the way doctors practice.
"If doctors are aware of the early-warning signs, they will be more likely to accurately diagnose and take care of the problem before a heart attack and it could lead to better heath care for women," Goldberg said.
Previous research by McSweeney and colleagues found that women who later identified an array of symptoms occurring before their heart attacks either ignored the signs or were misdiagnosed when they sought medical care.
More study is needed to help sort out the prevalence of each symptom in people at imminent risk for heart attack, and McSweeney said there's particularly a need to understand how often women not diagnosed with heart disease report similar problems.
Even so, women should be aware that when new unexplained symptoms appear, they need to seek medical care to determine the cause, especially if they have known cardiovascular risks such as smoking, high blood pressure, high cholesterol, diabetes or a family history of heart disease, McSweeney said.
"Heart disease is the No. 1 killer of women, yet women are more afraid of breast cancer. They don't realize heart disease is the thing they need to fear," she said.
The most common acute symptoms during heart attacks were shortness of breath (58 percent); weakness (55 percent); unusual fatigue (43 percent); and cold sweat and dizziness (both 39 percent).
_ Information from the Associated Press was used in this report.
Women and heart disease
This year an estimated 210,000 women will have a heart attack.
Heart disease is the single leading cause of death of American women, killing 254,630 in 2000. That's 49 percent of heart disease deaths.
By comparison, breast cancer kills about 40,000 women a year, and lung cancer nearly 63,000.
SOURCE: American Heart Association