BERLIN – Nearly 5% of patients with systemic lupus erythematosus have a seizure, most often soon after diagnosis, based on a review of more than 1,600 patients collected by an international consortium.
Among 1,631 patients with SLE who were enrolled in the Systemic Lupus International Collaborating Clinics (SLICC) cohort, 75 (4.6%) had one or more seizures during an average follow-up of 3.5 years, Dr. John G. Hanly reported at the annual European Congress of Rheumatology. The average time from first diagnosis of SLE to the patient’s first seizure was 0.14 years (51 days), and ranged from half a year prior to the SLE diagnosis to 7.5 years after diagnosis, said Dr. Hanly, a professor of medicine at Dalhousie University in Halifax, N.S.
The 75 affected patients had a total of 91 seizures, with 59 (79%) having a single seizure and the other 16 patients each having two seizures. "In the majority of cases the seizures resolve, do not require long-term antiseizure medication, and are not associated with a negative impact on mental or physical health–related quality of life," he said. Some 78% of the seizures appeared to be linked to SLE, whereas the other 13 seemed to result from other causes; 60 of the seizures were primary generalized, and the other 31 were focal.
In a multivariate analysis of demographic and clinical features, variables with a statistically significant link with an increased incidence of seizures were African ethnicity and lower educational status, each of which linked with a roughly doubled seizure rate, and organ damage outside of the nervous system, which was associated with a 50% increased rate. Educational status likely served as a marker for lower socioeconomic status and possibly reduced access to medical care, Dr. Hanly said.
The apparent associations between seizures and treatment with various lupus-related therapies were "complex," but treatment with an antimalarial drug appeared to confer protection against a seizure.
The patients who were included in the study appeared to be typical SLE patients, and each patient fulfilled at least four of the SLE classification criteria set by the American College of Rheumatology. The SLICC designed the cohort for an inception study, and hence required enrollment within 15 months from when patients first met the American College of Rheumatology’s SLE classification criteria. The cohort patients averaged 35 years old, 89% were women, and their average disease duration was almost 6 years. Their average SLE disease activity index was 5.3 (indicating moderate disease), and on average the patients showed a low level of organ damage.
Dr. Hanly said that he had no disclosures.