Risks of subsequent epilepsy among patients with hypertensive encephalopathy: A nationwide population-based study

• The incidence of epilepsy after hypertensive encephalopathy (HE) is 4.63/1000 person-years.
• HE is an independent indicator of the subsequent development of epilepsy.
• Physicians should be aware of epilepsy when assessing patients with HE.

BackgroundTo determine whether the diagnosis of hypertensive encephalopathy (HE) is linked to an increased risk of subsequent epilepsy by using a nationwide population-based retrospective study.MethodsOur study featured a study cohort and a comparison cohort. The study cohort consisted of all patients with newly diagnosed HE between 1997 and 2010, compiled from universal insurance claims data on patients with hypertension taken from the National Health Insurance Research Database. The comparison cohort comprised the remaining hypertensive patients without encephalopathy. The follow-up period was terminated following the development of epilepsy, death, withdrawal from the National Health Insurance system, or the end of 2010. We determined the cumulative incidences and hazard ratios (HRs) of epilepsy development.ResultsThe incidence of subsequent epilepsy was 2.25-fold higher in the patients with HE than in comparisons (4.17 vs. 1.85 per 1000 person-years), with an adjusted HR of 2.06 (95% CI = 1.66–2.56) in the multivariable Cox proportional-hazards regression analysis. The incidence of epilepsy was higher in men, younger patients with HE, and those with brain disorders.ConclusionsWe found that, in Taiwan, patients with HE are at an increased risk of subsequent epilepsy. Physicians should be aware of HE's link to epilepsy when assessing patients with HE.