Eclampsia tied to increased relative risk of seizure disorder

(HealthDay)—The relative risk of a seizure disorder after eclampsia is higher than that of women unaffected by eclampsia but remains extremely low, according to a study published online Nov. 7 in Obstetrics & Gynecology.

Kara A. Nerenberg, M.D., from the University of Calgary in Canada, and colleagues retrospectively evaluated data from 1,565,733 births from April 1, 2002, to March 31, 2014, to evaluate the incidence rate and relative risk of a seizure disorder after eclampsia.

The researchers found that 0.1 percent of pregnancies were affected by eclampsia, 1.1 percent by pre-eclampsia, and 3.9 percent by gestational hypertension. After a pregnancy with eclampsia, a future seizure disorder was significantly more likely (4.58/10,000 person-years) compared with a pregnancy without a hypertensive disorder of pregnancy (0.72/10,000 person-years; crude hazard ratio [HR], 6.09). This finding remained with minimal attenuation after multivariable adjustment for confounders (HR, 5.42). After pre-eclampsia, the risk of seizure disorder was doubled (adjusted HR, 1.96; 95 percent confidence interval, 1.21 to 3.17), but this was not the case after gestational hypertension (adjusted HR, 1.01; 95 percent confidence interval, 0.71 to 1.43).

"Women with eclampsia should be reassured that, although the relative risk of a seizure disorder is higher than unaffected women, the absolute risk is extremely low (approximately one seizure/2,200 person-years)," write the authors.