A Population‐Based Study of Posterior Reversible Encephalopathy Syndrome and Reversible Cerebral Vasoconstriction Syndrome During Pregnancy and Puerperium

BACKGROUND: Posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS) are related neurovascular conditions, with pregnancy as a shared risk factor. In this study, we aimed to describe shared and distinctive risk factors and outcomes in patients with pregnancy-associated PRES and/or RCVS. METHODS: In this retrospective, nationwide, population-based cohort study, the national healthcare registers were utilized to identify women with PRES and/or RCVS during pregnancy or puerperium during 1987-2016. Subsequent pregnancies, vascular events, and deaths until 2022 were identified. Medical records were reviewed to classify cerebrovascular events and collect clinical details. RESULTS: In total, 27 patients had pregnancy-associated PRES and/or RCVS (18 PRES; 5 PRES + RCVS; 4 RCVS) during 1987-2016, resulting in an incidence of 1.52 per 100,000 (95% Cl 1.02-2.18) deliveries. All patients with PRES ± RCVS had preeclampsia with severe features during late pregnancy or early puerperium. In contrast, isolated RCVS showed a weaker association to preeclampsia and occurred in late puerperium, with a median puerperal day of 26 (IQR 11-45). Altogether, 40.7% of all patients had a stroke, 90.9% of which were hemorrhagic. Preeclampsia was diagnosed in 90.9% of stroke patients. Maternal mortality was 3.7%, whereas perinatal mortality was 7.4%. At 3 months, 92.3% had a good recovery (mRS 0-2). During follow-up, stroke recurrence was 3.7% and 33.3% had subsequent uneventful, full-term pregnancies. CONCLUSIONS: Pregnancy-associated PRES and RCVS are potentially life-threatening, rare conditions that can result in hemorrhagic stroke. PRES ± RCVS is strongly associated with preeclampsia with severe features, whereas puerperal RCVS seems to be a separate, later-occurring condition.