Why Do Women Have More Strokes?
I’ve been hearing at lot lately about women’s risk of stroke. Can you tell me why strokes are more common among women? What can women do to prevent them?
Andrew Weil, M.D. | April 15, 2014
Both men and women are at risk for stroke. High blood pressure, smoking and diabetes are the primary risk factors in both sexes, but women have some additional risks that men don’t. These include complications of pregnancy, the use of birth control pills and hormone replacement therapy, a higher prevalence of migraine headaches and atrial fibrillation (a potentially serious abnormal heart rhythm that affects an estimated 2.2 million Americans and increases the risk of stroke in both sexes, but particularly among women 75 and older).
According to the American Stroke Association, each year more than half of the 795,000 strokes that occur annually in this country affect women. And women are more likely to die as a result – 60 percent of stroke deaths occur in women.
In recognition of the increased risks among women, in February of 2014 the American Heart Association and the American Stroke Association issued new guidelines designed to help women avoid strokes.
One well-known risk to women is preeclampsia, a complication of pregnancy that affects six to 10 percent of the nearly four million women who give birth every year. Preeclampsia is a dangerous elevation in blood pressure that can occur late in pregnancy. It doubles the risk for stroke and quadruples the risk for developing high blood pressure later in a woman’s life. One of the new guidelines advises women with a history of high blood pressure to consider taking low-dose aspirin and calcium supplements while pregnant, and recommends to doctors that these women be screened and treated for high blood pressure, obesity, smoking and high cholesterol to reduce their risk for stroke.
Here are some of the other new guidelines:
- Birth control pills: Before considering birth control pills, women should be screened for high blood pressure, since the combination increases the risk for stroke. Women taking birth control pills should not smoke because smoking while on the pill increases the risk of stroke.
- Migraines: Women who have migraines with aura (visual disturbances that precede the headache) are at increased risk for stroke. Smoking further increases that risk.
- Atrial fibrillation: Women over age 75 should be screened for atrial fibrillation, which increases the risk of stroke five-fold.
- Pregnancy: Women with high blood pressure or whose blood pressure was high during a previous pregnancy should ask their doctors about taking low-dose aspirin starting in the second trimester to lower the preeclampsia risk. Pregnant women with severe high blood pressure (160/110 mmHg or above) should be treated with medications that are safe during pregnancy. Doctors should also consider prescribing safe antihypertensive medications for pregnant women with moderately high blood pressure (150-159 mmHg/100-109 mmHg).
- Hormone replacement therapy: Once thought to reduce the risk of stroke, hormone replacement is now recommended only to reduce menopausal symptoms. It should be used for the shortest period possible and at the lowest effective dose.
Andrew Weil, M.D.
Sources:
“New guidelines for reducing stroke risks unique to women,” American Heart Association/American Stroke Association Scientific Statement, http://newsroom.heart.org/news/new-guidelines-for-reducing-stroke-risks-unique-to-women?preview=d9e7 accessed February 6, 2014