Moderate Exercise Counteracts HRT-Associated Stroke Risk

Exercise appeared to counteract the increased risk of stroke associated with postmenopausal hormone therapy, according to research presented last week at the American Heart Association’s/American Stroke Associations’ International Stroke Conference.

The surprise finding indicated that the exercise could be moderate, including taking a brisk walk, and that more strenuous activity, such as running, didn’t further reduce a woman’s stroke risk, the researchers noted. 

Pertinent Points:

- Moderate exercise appeared to counteract the increased risk of stroke associated with postmenopausal hormone therapy.

- More strenuous exercise did not further reduce the risk of stroke.

- Stopping hormone therapy resulted in a decline of stroke risk.

Among postmenopausal women taking hormone therapy, moderate exercise helped to offset an increased risk of stroke, but not entirely. Postmenopausal hormone therapy use was associated with a 30% increased risk for stroke (95% CI, 1.03-4.85), according to the abstract. But moderate to strenuous physical activity in the 3 years before enrollment decreased stroke risk by 20% (hazard ratio, 0.79; 95% CI, 0.71-0.98), the researchers reported.

After the women stopped taking hormones, stroke risk declined.

"The effects of physical activity and hormone therapy appear immediate and the benefits of physical activity are consistent in premenopausal and postmenopausal women," said Sophia Wang, PhD, the study’s lead author and professor in the department of population sciences within the Beckman Research Institute at the City of Hope in Duarte, California.

Wang suggested power-walking or tennis is likely enough activity to reduce the risk of stroke.

For the study, researchers analyzed information from the 133,479 women in the California Teachers Study to see how many suffered a stroke between 1996 and 2010.

Women with diabetes had an elevated stroke risk, the authors also reported, adding the caveat that this cohort included women who were also overweight.

“Physical activity, obesity and diabetes are all highly correlated with one another,” Wang explained. “Stroke prevention among diabetics is thus a particularly important scientific question to address.”

References:

Wang SS, Lakshminarayan K, Elkind M, et al. Physical activity reduces stroke risk among women in the California Teachers Study cohort. Poster presented at: International Stroke Conference 2014; February 13, 2014; San Diego.