Supplementary Material for: Preeclampsia and the long term risk of developing neurological disorders requiring hospital admission

Introduction: Preeclampsia is associated with acute neurological complications during pregnancy, but the subsequent risk of developing a neurological disorder is unclear. We determined if preeclampsia was associated with the long-term risk of neurological morbidity.
Methods: We conducted a longitudinal cohort study of 1,460,098 pregnant women with and without preeclampsia in Quebec, Canada, between 1989 and 2023. The main exposure measure was preeclampsia diagnosed in any pregnancy. Outcomes included hospitalization for cerebrovascular disease, epilepsy, and other neurological disorders up to three decades after pregnancy. Using Cox regression models adjusted for confounders, we estimated hazard ratios (HR) and 95% confidence intervals (CI) for the association between preeclampsia and neurological disorders during 27,659,555 person-years of follow-up.
Results: There were 1,460,098 women in the cohort, including 73,890 (5.1%) with preeclampsia. Women with preeclampsia had a higher incidence of neurological disorders than women without preeclampsia (113.2 vs. 79.3 per 100,000 person-years). Compared with no preeclampsia, preeclampsia was associated with 1.49 times the risk of later neurological hospitalization (95% CI 1.41–1.57). Preeclampsia was primarily associated with cerebrovascular disease (HR 1.89, 95% CI 1.76–2.03) and epilepsy (HR 1.39, 95% CI 1.24–1.57). A link with other neuropathology was less apparent, although severe preeclampsia was associated with neurodegenerative disorders. Severe hypertension, including early onset (HR 2.35, 95% CI 2.06–2.68), recurrent (HR 2.47, 95% CI 2.13–2.86), and superimposed preeclampsia (HR 2.60, 95% CI 2.17–3.12), was more strongly associated with neurological hospitalization overall.
Conclusion: Preeclampsia is associated with the long-term risk of developing cerebrovascular disease and epilepsy, but associations with other neurological disorders are less prominent.

引言：子痫前期（preeclampsia）与妊娠期急性神经系统并发症相关，但后续发生神经系统疾病的风险尚不明确。本研究旨在明确子痫前期是否与神经系统疾病的长期发病风险相关。
方法：本研究对1989年至2023年间加拿大魁北克省1,460,098名患有或未患子痫前期的孕妇开展了一项纵向队列研究。主要暴露因素为任何一次妊娠中诊断的子痫前期。结局指标包括妊娠后长达30年内因脑血管疾病、癫痫及其他神经系统疾病住院的情况。通过校正混杂因素的Cox回归模型（Cox regression models），我们在27,659,555人年的随访期间，估算了子痫前期与神经系统疾病相关性的风险比（hazard ratio, HR）及95%置信区间（confidence interval, CI）。
结果：队列共纳入1,460,098名女性，其中73,890名（5.1%）患有子痫前期。子痫前期女性的神经系统疾病发生率高于非子痫前期女性（113.2 vs. 79.3例/10万人年）。与未患子痫前期者相比，子痫前期患者后续因神经系统疾病住院的风险增加1.49倍（95% CI 1.41–1.57）。子痫前期主要与脑血管疾病（HR 1.89，95% CI 1.76–2.03）和癫痫（HR 1.39，95% CI 1.24–1.57）相关。其与其他神经病理学疾病的关联较不明显，但重度子痫前期与神经退行性疾病相关。重度高血压（包括早发性子痫前期（HR 2.35，95% CI 2.06–2.68）、复发性子痫前期（HR 2.47，95% CI 2.13–2.86）及叠加性子痫前期（HR 2.60，95% CI 2.17–3.12））与总体神经系统疾病住院风险的关联更强。
结论：子痫前期与脑血管疾病及癫痫的长期发病风险相关，但与其他神经系统疾病的关联较不显著。