Unusual Fatigue May Be Warning Symptom Of Heart Attack In Women

"Since women reported experiencing early warning signs more than a month prior to the heart attack, this could allow time to treat these symptoms and to possibly delay or prevent the heart attack," said Jean C. McSweeney, Ph.D., R.N., lead author and a professor in the College of Nursing at the University of Arkansas for Medical Sciences in Little Rock.

Researchers recruited 515 women diagnosed with a heart attack and discharged from five different medical sites in Arkansas, North Carolina and Ohio within the previous four to six months. The women were age 66 on average, and 93 percent were Caucasian, 6.2 percent black and 0.4 percent Native American. Data collection occurred over three years.

To assess symptoms that might suggest an imminent heart attack, the researchers used the McSweeney Acute and Prodromal Myocardial Infarction Symptom Survey (MAPMISS), a telephone research tool developed by McSweeney and her colleagues. The survey lists 33 early, or prodromal, signs and 37 acute symptoms that women identified in previous studies. The researchers defined prodromal signs as being new or changing in intensity or frequency before the heart attack, being intermittent before the heart attack, and disappearing or returning to previous levels after the heart attack. Acute symptoms were defined as those appearing with the heart attack and not resolving until women received treatment.

The survey also included questions about other health problems, risk factors, medications and demographics. About 95 percent of women reported having new or different symptoms more than a month before their heart attacks that resolved after their heart attacks. This led them, in retrospect, to believe that these symptoms were related to the subsequent heart attack. The most common early symptoms were: unusual fatigue -- 70 percent; sleep disturbance -- 48 percent; shortness of breath -- 42 percent; indigestion -- 39 percent and anxiety -- 35 percent.

Only 30 percent reported chest discomfort before their heart attack. They described the discomfort in terms like aching, tightness and pressure – not pain, McSweeney said.

"Women need to be educated that the appearance of new symptoms may be associated with heart disease and that they need to seek medical care to determine the cause of the symptoms, especially if they have known cardiovascular risks such as smoking, high blood pressure, high cholesterol, diabetes, overweight or a family history of heart disease," she 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 assistance.

McSweeney emphasized the importance of health care providers being aware of the symptoms women experience. While these early symptoms may not be specific in predicting an imminent heart attack, the "appearance of these symptoms, in conjunction with women's standard cardiovascular risk factors, may assist providers in determining at-risk women who should undergo cardiovascular diagnostic tests," she said.

Little has been known about the acute warning signs that women experience with heart attack, she said. But it is clear that women's experiences differ from the symptoms they expect.

In this study, researchers found that 43 percent of women reported no chest discomfort during their heart attack. For those who did, the main locations were in the back and high chest.

"Lack of significant chest pain may be a major reason why women have more unrecognized heart attacks than men or are mistakenly diagnosed and discharged from emergency departments," McSweeney said. "Many clinicians still consider chest pain as the primary symptom of a heart attack."

Other acute symptoms women reported were: shortness of breath -- 58 percent; weakness -- 55 percent; unusual fatigue -- 43 percent; cold sweat -- 39 percent and dizziness -- 39 percent.

The researchers noted that the study sample was primarily Caucasian. "We do not know if women's early warning and/or acute symptoms may vary according to their race, but we will address this issue with our ongoing study with minority women," McSweeney explained.

Also, there was not a control group of women without diagnosed heart disease, so it is unknown how many of these women might experience similar preliminary symptoms. Further research is needed to address these issues.

Co-authors are Marisue Cody, Ph.D., R.N.; Patricia O'Sullivan, Ed.D.; Karen Elberson, Ph.D., R.N.; Debra K. Moser, DNSc, R.N. and Bonnie J. Garvin, Ph.D., R.N. The National Institute of Nursing Research, part of the National Institute of Health, funded the study.