Treatment of epilepsy in multiple sclerosis

The prevalence of epilepsy is increased in multiple sclerosis (MS), but information on AED treatment and seizure outcome is scarce. We describe epilepsy characteristics including the use of AEDs and proportion of seizure-free patients at two tertiary hospitals in Sweden.

We retrospectively studied electronic medical records of all patients with a diagnosis of MS and seizures at Sahlgrenska university hospital and Uppsala university hospital. Clinical data were reviewed until 2017.

We identified a total of 62 MS patients with at least one seizure. Median age at the first seizure (before or after MS) was 41 years (range 0-80). The most common MS disease course at the first seizure was secondary progressive MS, the neurological disability was considerable, and most patients had several MRI lesions at their first seizure. The first EEG demonstrated epileptiform discharges in 38% and unspecific pathology in 40%. Current seizure status could be determined for 37 patients. Out of these, 46% had been seizure free for more than one year at last follow-up. The majority of patients (65%) were on monotherapy at last follow-up. Carbamazepine was the most commonly used first AED, with a retention rate of 52%. No individual AED was associated with a particularly high rate of seizure freedom. The most common reason for discontinuation of the first AED was side-effects.

Seizure freedom rates were low, perhaps indicating a need for higher ambitions in management. Side effects of AEDs may be a particular concern when treating epilepsy in patients with MS.