Various aspects of Pregabalin effectiveness as add-on therapy in patients with refractory epilepsy
Molecular & Cellular Epilepsy
The purpose of the study was to perform an open, prospective study on various aspects of PGB effectiveness in Bulgarian patients with drug-resistant epilepsy. It was open, prospective and was performed with the participation of patients with epilepsy who attended the Clinic of Neurology at the University Hospital in Plovdiv, Bulgaria for a regular examination in cases of unsatisfactory seizure control or for adverse events from treatment. Patients completed diaries about seizure frequency,
... ity, and adverse events. There were regular documented visits at 3 or 6 months during the first year of treatment with pregabalin (PGB) and at 6 months or 1 year afterwards, with dynamic assessment of seizure frequency, severity, adverse events, and EEG recordings. PGB was applied as add-on treatment in 47 patients (24 males, mean age 34 years) with long duration of epilepsy, manifested with predominantly severe and very frequent partial, a combination of partial and generalized or generalized tonic-clonic seizures, refractory to the prescribed, usually combined treatment with a variety of AEDs. There was relatively mild, stable though, dynamic improvement of seizure severity, satisfactory seizure frequency reduction in 43.5% of participants, stable mean seizure frequency reduction (48-51%) from the 6-th to the 24-th month of the study, as well as a high and stable responder rate (58.7-62.5%) during the same period. New seizure types (generalized tonic-clonic, generalized atonic) appeared in 2 patients. The final clinical efficacy was higher in patients without seizure clusters or status epilepticus in the disease course. EEG improvement was found in a small percentage of patients (less than a third) and it did not correlate with clinical findings and their dynamics. Adverse events (dizziness/vertigo, sleepiness, memory impairment, increased weight, diplopia, lymphadenomegaly, impaired concentration, gastro-intestinal discomfort, transient leucopenia, rash, nausea, anxiety) were reported in 25.53% of patients. They were usually severe and became a cause of treatment termination in 12.8% of patients. In conclusion, PGB treatment is associated with: low and stable improvement of seizure severity, good and stable reduction of seizure frequency, a possibility of seizure control worsening, possible appearance of new seizure types, rare EEG dynamics, acceptable safety and tolerability.