Stroke risk after pregnancy-associated stroke

Stroke risk after pregnancy-associated stroke | Image Credit: © Chinnapong - © Chinnapong - stock.adobe.com.

According to a recent study published in JAMA Network Open, pregnancy-related risk factors are associated with decreased stroke recurrence risks but increased venous thromboembolism (VTE) and acute coronary syndrome risks.

About 30 pregnancy-associated strokes per 100,000 pregnancies have been recorded, with a study in France estimating first-ever strokes occurring during pregnancy, peripartum, or within 6 weeks postpartum in 24 per 100,000 person-years. Increases in pregnancy-associated ischemic stroke (IS) and hemorrhagic stroke (HS) have also been observed over time.

Pregnant women have been seen with an increased incidence rate of intracerebral hemorrhage (ICH) and cerebral venous thrombosis (CVT). However, there is little data on the pregnancy and associated risk factors.

To determine the association between pregnancy-associated stroke and rates of stroke recurrence, cardiovascular events, and death, investigators conducted a study using data from the French health care database Système National des Données de Santé (SNDS). Data on reimbursed health care expenses were included in the SNDS.

Participants included women aged 15 to 49 years with a hospitalization for acute stroke any time from January 1, 2010, to December 31, 2018. Exclusion criteria included having a history of cerebrovascular events from 2006 to 2009 or a non-general health insurance scheme.

There were 2 groups formed, 1 comprised of women who experienced stroke during pregnancy or while postpartum, and another without pregnancy-associated stroke. The Cohort of Cardiovascular Diseases in Pregnancy study was consulted to determine stroke incidence during pregnancy or while postpartum.

Follow-up occurred from hospital discharge to December 31, 2020, during which stroke or cardiovascular event incidence leading to hospitalization was recorded. Early recurrent stroke was defined as, “a subsequent hospitalization for stroke in the first 30 days,” while strokes requiring hospitalization after 30 days were considered recurrent strokes.

There were 1204 strokes associated with pregnancy and 31,697 not associated with pregnancy from 2010 to 2018, with a mean age of 31.5 years during pregnancy-associated strokes and 39.6 years during non-pregnancy-associated strokes. 

In those with pregnancy-associated strokes, incidence rates were 41% for ISs, 40.4% for HSs, and 16.3% for CVTs. In those without pregnancy-associated strokes, incidence rates were 60.5% for ISs, 36.9% for HSs, and 1.7% for CVTs.

Over a mean 5.5-year follow-up period, recurrent stroke was seen in 6.3% of pregnancy-associated strokes, with an incidence rate of 11.4 per 1000 person-years. In comparison, non-pregnancy-associated strokes had a recurrent stroke rate of 8.7% and an incidence rate of 17.9 per 1000 person-years over a mean follow-up period of 4.8 years.

ICH stroke was associated with the highest rate of recurrence both when associated and when not associated with pregnancy. VTE incidence in pregnant women with a first CVT was 10.5 compared to 4.1 in nonpregnant women with a first CVT. Pregnancy-associated first ICH also led to higher ICH and VTE incidence rates than non-pregnancy-associated first ICH.

Of recurrent stroke cases after pregnancy-associated stroke, 6.6% were within 30 days, 60.5% from 30 days to 1 year, and 32.9% after 1 year. Of recurrent stroke cases after non-pregnancy-associated stroke, 13.9% were within 30 days, 48.1% from 30 days to 1 year, and 38.1% after 1 year. Higher rates of recurrent stroke were observed among women with non-pregnancy-associated stroke.

In the follow-up period, hospitalization for nonstroke vascular disease was seen in 13.6% of women with pregnancy-associated stroke, and death in 4.1%. Cardiovascular event and death risks were lower in this population, but increased rates of VTE and acute coronary syndrome were observed.

These results indicated decreased risks of pregnancy-associated risk factors for stroke after the pregnancy and postpartum periods. However, increased risks of VTE and acute myocardial infarction following pregnancy-associated stroke should be considered when evaluating risk factors.

Reference

Béjot Y, Olié V, Lailler G, et al. Comparison of stroke recurrence, cardiovascular events, and death among patients with pregnancy-associated vs non–pregnancy-associated stroke. JAMA Netw Open. 2023;6(6):e2315235. doi:10.1001/jamanetworkopen.2023.15235