Idiopathic Intracranial Hypertension Is Associated With an Increased Risk of Hypertensive Pregnancy Disorders.

Background: Idiopathic intracranial hypertension (IIH) mainly occurs in women of a reproductive age who are overweight or obese. As pregnancy occurs in this age group, it is important to understand whether there are associations between IIH and pregnancy. The purpose of this study was to determine the incidence of IIH development during a pregnancy and whether IIH is associated with hypertensive disorders of pregnancy (HDP).

Methods: In this retrospective cohort analysis, electronic health records from a tertiary care center were used to identify patients with IIH. Patients who had a diagnostic code for IIH or papilledema and were seen between June 1, 2012, and September 1, 2023, were included. After meeting the revised Dandy diagnostic criteria, patients were evaluated for a history of pregnancy before, during, or after their IIH diagnosis and hypertensive disorders including preeclampsia/eclampsia, HELLP (hemolysis, elevated liver enzymes, low platelet count) syndrome, and hypertension. Incidence and risk ratios (RR) were calculated comparing patients with IIH with controls without IIH. To corroborate these results while controlling for obesity and migraine, the TriNetX platform housing more than 100 million patients was used to design a case-control analysis evaluating the odds of an IIH patient having an HDP.

Results: Two hundred ninety-two IIH patients with a prior pregnancy were identified of which 7% developed new onset IIH during pregnancy. Patients had increased risks of all HDP including eclampsia (RR: 12.92, 95% CI: 5.35, 31.22), preeclampsia (2.39, CI 1.84, 3.10), and HELLP syndrome (6.72, CI 2.16, 20.90) compared with controls. Patients with IIH also had higher risks of ectopic pregnancies and miscarriages (P < 0.05). When controlling for obesity and migraine, patients continued to have increased odds of all HDP and eclampsia (P < 0.05).

Conclusions: Patients with IIH had an increased risk of having an HDP, especially eclampsia and HELLP syndrome highlighting a need for increased clinical monitoring of these patients during pregnancy.