Predictors of Incident Seizure in Systemic Lupus Erythematosus

Objective. The risk factors for incident seizures in systemic lupus erythematosus (SLE) were prospectively determined in a cohort study.

Methods. A total of 2203 patients with SLE followed longitudinally in the Hopkins Lupus Cohort were analyzed. Demographic variables, clinical manifestations, laboratory tests, and SLE disease activity were recorded at each quarterly visit. Adjusted estimates of association of risk factors for onset of seizure were derived using pooled logistic regression. We examined incident seizures in 3 ways: at the time of diagnosis, more than 45 days after the diagnosis of SLE, and after cohort entry.

Results. Of 2203 patients with no history of seizure prior to SLE diagnosis, 157 (7.13%) had the first seizure occurrence at the time of (37 patients, 1.68%) or after diagnosis (120 patients, 5.45%) of SLE. The risk of seizure occurring around the time of SLE diagnosis was higher in patients with a history of malar rash (p = 0.002), proteinuria (p = 0.004), and psychosis (p < 0.001). Multivariable analysis of the first seizure occurring after the diagnosis of SLE showed that history of low C3 (p = 0.0078), psychosis (p < 0.0001), cranial or peripheral neuropathy (p = 0.0043), anti-Sm antibody (p = 0.0551), renal involvement (p = 0.0177), and current corticosteroid dose (p < 0.0001) were independently associated with a higher incidence of seizure. Disease activity was not predictive after adjusting for corticosteroids.

Conclusion. Risk of seizure after diagnosis of SLE is increased in those patients with prior psychosis, neuropathy, proteinuria, anti-Sm, low C3, and use of corticosteroids.