Epileptic seizures, cranial neuralgias and paroxysmal symptoms in remitting and progressive multiple sclerosis.

The occurrence of a first epileptic seizure, spinal or brainstem paroxysmal symptom and cranial neuralgia during 25 years after onset was studied in a population-based multiple sclerosis (MS) cohort of 255 patients. Epileptic seizures occurred in 20, paroxysmal symptoms in 11 and cranial (trigeminal, intermedius, retroauricular or occipital) neuralgia in 11 patients. The yearly incidence of epileptic seizures in MS was estimated to be 349(+/-153)/100,000, approximately seven times higher than in the general population. The yearly incidence of a first paroxysmal symptom in the present material was calculated to be 190 cases in 100,000 MS patients, and the yearly incidence of cranial neuralgia was 189 cases in 100,000 MS patients. The epileptic seizures were more frequent during the progressive course than in the relapsing-remitting (RR) course. The frequencies of paroxysmal symptoms and cranial neuralgia did not differ between these two disease courses. A coincidence of epileptic seizures and a decline in cognitive functioning not seen among patients with paroxysmal symptoms was found The relatively late occurrence of epileptic seizures indicates that the frequency of epileptogenesis, known to involve neuronal damage, increases in the later stages of MS.