Women with preeclampsia, a common complication of pregnancy, face a heightened risk of stroke during pregnancy and postpartum if they have urinary tract infections, chronic high blood pressure, or clotting or bleeding disorders, according to a study by researchers at Columbia University Mailman School of Public Health, Columbia University Medical Center (CUMC), and New York-Presbyterian Hospital.
[Photo: Dr. Mitchell S.V. Elkind]
The study, titled “Risk Factors for Pregnancy-Associated Stroke in Women with Preeclampsia,” is among the most comprehensive analyses of its kind. Findings are published online in the journal Stroke.
The investigators have suspected that certain conditions raise the risk of stroke in women with preeclampsia, but few studies have taken a rigorous look at this issue. Because strokes can be so devastating, it is critical to know whether these are just random events or due to modifiable risk factors.
Preeclampsia–newly elevated blood pressure during pregnancy–develops in about 3 to 8 percent of all pregnant women, according to the researchers.
The cause of preeclampsia is not well understood. While preeclampsia can be mild and symptomless, it can quickly become severe. Left untreated, severe preeclampsia can have serious consequences for both mother and fetus. One of the most dangerous complications is pregnancy-associated stroke, which occurs up to 6 times as often in women with preeclampsia compared with pregnant women overall.
The researchers analyzed the health records of 197 women who had a preeclampsia-related stroke and 591 women with preeclampsia who did not have a stroke, according to the New York State Department of Health inpatient database. The incidence of stroke in women with preeclampsia was over 200 per 100,000 deliveries, and more than one in 10 women in the study who had a preeclampsia-related stroke died in the hospital.
Women with preeclampsia who had chronic hypertension, bleeding or clotting disorders, or infections–particularly urinary tract infections–appeared to be at significantly increased risk of stroke.
“The role of infection was perhaps the biggest question mark going into the study,” said Dr. Eliza C. Miller, a postdoctoral vascular neurology fellow in the department of neurology at New York-Presbyterian/Columbia University Medical Center, and lead author. “Infections cause inflammation, which is known to play an important role in triggering stroke, especially in young people. Preeclampsia itself is an inflammatory disorder. Infections may be what pushed some of these women over the edge.”
About two-thirds of preeclampsia-related strokes occur after birth, when the mother has gone home. With all the stress of having a new baby, mothers sometimes ignore symptoms like headaches that could be a sign of a serious problem.
“We think it is important for women with preeclampsia and their doctors to know that the risk of stroke doesn’t end with delivery. Our findings suggest that pregnant and postpartum women with preeclampsia should pay close attention to new symptoms and occurrence of infections,” said co-author Dr. Mitchell S.V. Elkind, Columbia professor of epidemiology and professor of neurology at CUMC’s Sergievsky Center, and an attending neurologist at the New York-Presbyterian Hospital.
The study was supported by the National Institute of Neurological Disorders and Stroke.