Women, Exercise and Risk of Death


(Ivanhoe Newswire) -- For the first time, women have their own chart to determine what their fitness level should be at any given age. In the past, doctors have used information from a male chart for females, but a new study finds men and women are not created equally when it comes to exercise capacity and the risk of death.

"This is the first study of its kind in women," says Martha Gulati, M.D., a cardiologist at the Bluhm Cardiovascular Institute of Northwestern Memorial Hospital in Chicago. "Despite extensive research on the role of exercise stress testing and exercise capacity, there has been a lack of data on what is normal or expected for healthy women. Until now, they have been evaluated using the men's [alignment chart], which does not provide an accurate assessment for women."

During a patient's stress test exercise capacity is determined based on the speed and grade of a treadmill. Doctors determine the maximum oxygen upload for a given workload.

To create an alignment chart, or nanogram for women, more than 10,000 women underwent the stress test. Researchers developed a chart to determine exercise capacity. Survival data was obtained to estimate rate of death. They found the relationship between exercise capacity and the risk of death from cardiac cause was the same in all age groups. Those with a poor exercise capacity had an especially high mortality rate.

Researchers say the use of nanograms for women help to lessen the number of false positives. Researchers say if they had used the male chart, 800 women would have been told they were at risk for death when they were not, or vice versa. Dr. Gulati adds, "As age increases, so does the difference in predicted exercise capacity between men and women."

SOURCE: New England Journal of Medicine, 2005;353:468-475