Measuring a woman's heart rate at rest can help predict her risk of heart attack or dying from heart disease, giving doctors a simple, inexpensive way to monitor health risks, researchers said on Wednesday.
The study published in the British Medical Journal showed that postmenopausal women who had the highest resting heart rate were 26 percent more likely to suffer a heart attack or die from cardiovascular disease than those with the lowest rates.
Previous studies have linked resting heart rate to such problems in men but the relationship has been less certain for women, in part because trials did not include enough women to get a statistically significant result, researchers said.
"You can't assume it applies in women the same as men," said Judith Hsia, a researcher who led the study while at George Washington University in Washington. "The onus is on the scientists to show it, and for heart rate now we have."
Heart disease is the world's leading cause of death. It is caused by fatty deposits that harden and block arteries, high blood pressure which damages blood vessels, and other factors.
The U.S. team measured the heart rates of 129,135 postmenopausal women with no history of heart problems. Resting heart rate measures beats per minute after sitting still to gauge how well the heart works when not stressed.
Women with resting heart rates of more than 76 beats per minute were found to be 26 percent more likely to have a heart attack or die from heart disease than those with heart rates of 62 beats per minute or lower, the researchers said.
"People have to put in perspective that it is not as much as smoking but it is still a clinically meaningful amount," Hsia said in a telephone interview.
The researchers compensated for factors known to increase heart attack and disease risk such as high blood pressure, high cholesterol, smoking and drinking, and monitored the women for an average of nearly eight years.
Although resting heart rate is usually lower among people who are physically fit, the researchers said this measurement could help predict heart attack risk for women regardless of how much they exercise.
Researchers said they found no correlation between resting heart rate and stroke.