Women with endometriosis at higher risk of stroke, study suggests

Women with endometriosis may have a higher risk of having a stroke, a new study has found.

Researchers who monitored more than 112,000 women over three decades found those with endometriosis were 34 per cent more likely to suffer a stroke.

Endometriosis is a chronic inflammatory condition where tissue similar to the lining of the womb starts to grow in other places, such as the ovaries and fallopian tubes. It is estimated to affect one in 10 women of reproductive age.

Previous research has found that women with endometriosis are at greater risk of cardiovascular diseases such as heart attack, high blood pressure and high cholesterol.

The new study, by US researchers, examined the link between endometriosis and the development of ischemic stroke (caused by blood clots blocking blood flow) or hemorrhagic stroke (caused by bleeding in the brain.)

It involved 112,056 female nurses in 14 US states who were aged between 25 and 42 years old at the start of the study in 1989. They were monitored by researchers up to 2017.

Endometriosis was reported in 5,244 women, and they were found to be at 34 per cent greater risk of stroke than the 106, 812 without the condition.

Ninety-three per cent of the participants were white women.

“These findings suggest that women with a history of endometriosis may be at higher risk of stroke,” said Stacey A. Missmer, study senior author and professor of obstetrics, gynecology and reproductive biology at Michigan State University College of Human Medicine in Grand Rapids.

She added: “Clinicians should look at the health of the whole woman, including elevated blood pressure, high cholesterol and other new stroke risk factors, not only symptoms specifically associated with endometriosis, such as pelvic pain or infertility.”

Researchers analysed data collected every two years for many possible confounders or risk factors, including alcohol intake, current body mass index, menstrual cycle pattern in adolescence, current oral contraceptive and postmenopausal hormone exposure, smoking history, diet, physical activity, aspirin use, ethnicity and income.

Additionally, researchers investigated if the link between endometriosis and risk of stroke could be explained by other mediating factors such as high blood pressure, high cholesterol, hysterectomy (removal of the uterus), oophorectomy (removal of the ovaries) and postmenopausal hormone therapy.

During the 28 years of follow-up including medical record confirmations, researchers documented 893 strokes.

But the study, published in Stroke, the flagship journal of the American Stroke Association, had several limitations. Data detailing subtypes of strokes was not available. As a result, the relationship between subtypes of strokes and endometriosis could not be evaluated.

Researchers were also unable to determine the impact of time from endometriosis-associated symptom onset and age at diagnosis.