Early Vigabatrin Treatment Before Seizure Onset Decreased Interictal Epileptiform Discharges Over the Duration of the PREVeNT Study.

BACKGROUND

The PREVeNT trial enrolled 72 infants with tuberous sclerosis complex using the presence of interictal epileptiform discharges (IEDs) on a one-h electroencephalography (EEG) to randomize into a trial of placebo versus early vigabatrin. Here, we ask if early vigabatrin impacts IED presence over the first 3 years of life.

METHODS

Participants underwent an EEG every 6 weeks/first year of life, every 3 months/second year of life and once at age 36 months. EEGs were reviewed by two treatment blinded electrophysiologists; if they disagreed, a third reader adjudicated.

RESULTS

Seven hundred ninety-three EEGs were recorded, with IEDs present in 33.5% and at a higher percentage in the placebo arm of the study (n = 27 participants, 45.9% of 296 EEGs) than in the early vigabatrin group (n = 29, 34.3% of 332 EEGs) P = 0.0496. Infantile spasm-free participants in the vigabatrin group drove this reduction: placebo n = 14/26 without spasms, 41.7% of EEGs had IEDs versus vigabatrin n = 23/29 without spasms, and 27.7% of EEGSs had IEDs, P = 0.0185. In contrast the placebo group with spasms n = 12/26 had 51.9% IED positive EEGs versus early vigabatrin n = 6/29 with spasms had 60.3% IED positive, P = 0.5182. Overall, participants with spasms n = 18 had a higher rate of EEGs with IEDs versus those without n = 37, 54.8% vs 33.0%, P = 0.0005.

CONCLUSIONS

Early treatment with vigabatrin decreased by ∼20% the proportion of EEGs with IEDs over 3 years. Vigabatrin group participants who did not develop epileptic spasms drove this reduction. Participants who developed spasms in either group had IEDs in over half of their EEGs.