The risk for hemorrhagic and ischemic stroke may persist for up to 17 years in women who have hypertensive disorders of pregnancy, according to a study published in Stroke.
The 17-year nationwide, retrospective cohort study included women with vs without hypertensive disorders of pregnancy (n=13,617 vs n=54,468, respectively) in Taiwan. All women were aged between 18 and 45 years. Hypertensive disorders of pregnancy were stratified into 4 subtypes: gestational hypertension, chronic hypertension, chronic hypertension with superimposed preeclampsia, and preeclampsia/eclampsia. The study’s primary outcome was stroke, stratified into ischemic vs hemorrhagic stroke. The chi-squared test was used to compare basic characteristics between the 2 cohorts, while incidence of stroke was compared using multivariate Cox regression to find the adjusted hazard ratio (aHR).
Compared without, women with hypertensive disorders of pregnancy were at 1.71 (95% CI, 1.46-2.00) times greater risk for stroke (ischemic: aHR, 1.60 [95% CI, 1.35-1.89]; hemorrhagic: aHR, 2.98 [95% CI, 2.13-4.18]; P <.001 for all). Even after 10 to 15 years postchildbirth, the overall stroke risk remained significantly higher among the group with hypertensive disorders of pregnancy (aHR, 2.04; 95% CI, 1.47-2.83; P <.001). Ischemic stroke risk peaked 1-3 years after childbirth (aHR, 2.14; 95% CI, 1.36-3.38; P <.001), and the risk for hemorrhagic stroke increased gradually over time with an aHR of 4.64 (95% CI, 2.47-8.73; P <.001) 10-15 years after childbirth.
Chronic hypertension with superimposed preeclampsia was associated with the highest stroke risk, with an aHR of 3.86 (95% CI, 1.91-7.82; P <.001), with the next highest risk presented by preeclampsia/eclampsia (aHR, 2.00; 95% CI, 1.63-2.45; P <.001), followed by gestational hypertension (aHR, 1.68; 95% CI, 1.13-2.52; P <.05). The lowest stroke risk was associated with chronic pre-existing hypertension (aHR, 1.27; 95% CI, 0.97-1.68; P >.05). Multiple types of hypertensive disorders of pregnancy with comorbid preeclampsia were associated with an aHR of 5.48 (95% CI, 1.14-26.42; P <.05).
Limitations to this study include a lack of information on body weight, body mass index (BMI), physical activity, alcohol consumption, or smoking habits of the participants, which precluded evaluating how these factors impacted stroke outcome.
“Women with a previous [hypertensive disorders of pregnancy] history should be aware that the risk of stroke may persist for even more than a decade and take appropriate precautionary measures or behavior modifications like regular blood pressure monitor, avoiding cigarette smoking and heavy drinking, or preventive medication, such as aspirin, especially for women with multiple [hypertensive disorders of pregnancy] combined with preeclampsia,” the study authors wrote.
Hung SK, Lee MS, Lin HY, et al. Impact of hypertensive disorders of pregnancy on the risk of stroke stratified by subtypes and follow-up time. Stroke. Published online January 5, 2022. doi:10.1161/STROKEAHA.121.034109