Prevalence of epilepsy in a cohort of patients with multiple sclerosis

Abstract Introduction Epilepsy prevalence is 0.27–1.7% in general population. However, higher figures have been reported in Multiple Sclerosis (MS) patients, suggesting this association is not coincidental. Methods We retrospectively reviewed the records of MS patients seen between 2009 and 2012 at Pontificia Universidad Catolica of Chile's Multiple Sclerosis Center. Results Of 310 MS patients, ten had the diagnosis of epilepsy (3.2%). These patients were younger, and had an earlier onset of symptoms of MS compared to the group without epilepsy (32 vs. 40 years, p =0.04 and 25 vs. 32 years, p =0.02, respectively). In 4 patients, seizures were the first MS symptom and the most frequent seizure type was partial secondary generalized (6 patients). MRI showed cortical lesions in all patients. Patients with poor epilepsy control (frequent seizures or development of status epilepticus) had lower brain volumes and worse cognitive performance. All patients received antiepileptic drugs as well as immunomodulatory therapy. Conclusion Patients with epilepsy and MS are younger and have an earlier onset of symptoms. Since most seizures were partial, the presence of cortical lesions and progressive brain atrophy could probably be the pathophysiological mechanism underlying this association.