Objective: To evaluate the frequency and risk factors of epileptic seizures in a large cohort of patients with systemic lupus erythematosus (SLE).
Methods: Five hundred nineteen consecutive patients with SLE were studied, with follow-up ranging from 4 to 7.8 years. The type and frequency of risk factors associated with acute and recurrent epileptic seizures in SLE were determined.
Results: Sixty (11.6%) patients with epileptic seizures were identified. Epileptic seizures occurred at the onset of SLE symptoms in 19 (31.6%) and after the onset of SLE in 41 of 60 (68.3%) patients. Fifty-three of 60 (88.3%) patients had acute symptomatic epileptic seizures, and 7 of 60 (11.7%) had recurrent epileptic seizures. Variables associated with acute epileptic seizures at SLE onset were stroke (p = 0.0004) and antiphospholipid antibodies (p = 0.0013). Epileptic seizures during follow-up were related to nephritis (p = 0.001), antiphospholipid antibodies (p = 0.005), and epileptic seizures at disease onset (p = 0.00001). All seven patients who presented recurrent epileptic seizures had antiphospholipid syndrome and interictal epileptic abnormalities on EEG.
Conclusions: Epileptic seizures were observed in 11.2% of systemic lupus erythematosus (SLE) patients. Antiphospholipid antibodies and stroke were related to epileptic seizures at SLE disease onset. Patients with renal flares, epileptic seizures at SLE disease onset, and antiphospholipid antibodies were at greater risk for acute symptomatic seizures during follow-up. Recurrence of epileptic seizures occurred in 1.3% of patients and was associated with antiphospholipid syndrome.