ARTICLE IN BRIEF
Using responses to questionnaires from a study of teachers and administrators in California, investigators determined that moderate and/or strenuous physical exercise appeared to offer some protection for women against the risk of stroke, and menopausal women who exercised and were being treated with hormone replacement therapy attenuated their risk for stroke.
SAN DIEGO—Moderate and/or strenuous physical exercise appears to offer some protection for women against the risk of stroke, researchers said here at the International Stroke Conference sponsored by the American Heart Association/American Stroke Association.
In addition, the research team determined that menopausal women who exercise and are being treated with hormone replacement therapy can attenuate their risk of stroke.
In a large cohort of women in the California Teachers Study, performing “moderate physical exercise conferred a 20- to 30-percent reduction in risk for ischemic stroke,” reported Sophia Wang, PhD, professor of population science at the Beckman Research Institute at City of Hope Medical Center in Duarte, CA.
“More women have strokes than men; and women suffer greater disability from strokes than men do,” Dr. Wang said, which is why the issue has great public health importance. “More women die from stroke than men as well.”
A major reason for the difference is that women tend to live longer than men, and strokes are more frequent with advancing age, she said.
The study was supported by grants from the National Institute of Neurological Disorders and Stroke.
Dr. Wang and colleagues accessed data gathered in the California Teachers Study that included 133,479 women who were public school teachers and administrators. The participants were geographically and socioeconomically diverse. The participants were mailed questionnaires every four to five years. The results were linked to the California Cancer Registry and the California hospitalization discharge database; strokes were recorded in the hospitalization records.
The researchers identified women who experienced strokes — 2,416 ischemic events and 710 hemorrhagic strokes — between 1995 and 2010.
The questionnaires asked participants to quantify hours of physical exercise performed during the previous three years in hours per week. The researchers stratified the women by moderate — brisk walking, cycling, sports such as volleyball and golf — and by strenuous activities such as swimming, running, calisthenics, aerobics, jogging, basketball, and racquetball, and they determined that both forms of activity were beneficial.
“We found that it was difficult to disentangle what women considered moderate activity and what was considered strenuous activity,” Dr. Wang said. When they did attempt to determine a difference, all the results appeared to be headed in the same direction, so the researchers combined the groups.
For the purposes of the study, women who said they exercised less than 30 minutes a week were compared with women who exercised more than 30 minutes up to two hours a week; who exercised more than two hours a week up to 3.5 hours a week; who exercised more than 3.5 hours a week up to 5 hours a week; and who exercised more than 5 hours a week. [See “Exercise and Reduction in Stroke Risk.”]
“We observed that even after the 10-year difference in time points, the robust decrease in stroke events continued,” Dr. Wang said.
Among menopausal women who currently use hormone replacement therapy and exercised less than 30 minutes a week, the risk of ischemic stroke was 59 percent higher than menopausal women who never used hormone replacement therapy.
Dr. Wang said her study was limited by the fact that the physical activity was self-reported. On the other hand, the study included a large cohort of participants, extensive detail on risk factors reported over time, and the adjustment of the statistical models for known clinical and behavioral risk factors, she said.
In particular, she told Neurology Today, the researchers adjusted their model for obesity and diabetes, recognizing that lack of exercise could be a surrogate marker of sedentary lifestyles.
“We saw that physical exercise — even just moderate exercise — is shown to not only reduce the incidence of strokes overall, but in women who have been taking hormone replacement therapy, as well,” said Bruce Ovbiagele, MD, FAAN, a professor of neurology at the Medical University of South Carolina in Charleston. The results support the need to point patients to the US Physical Activity Guidelines for Americans, which provide guidance on evidence-based recommendations for exercise for adults of all ages.
EXERCISE AND REDUCTION IN STROKE RISK
Investigators found that the more hours women exercised each week, the greater the reduction in stroke risk.