The fate of spikes in self-limited epilepsy with centrotemporal spikes: Are clinical and baseline EEG features effective?

OBJECTIVE: We aimed to evaluate the effects of demographic, clinical and electroencephalographic features on spike reduction with a focus on the first EEG characteristics. METHODS: This single-center retrospective study was conducted on SLECTS patients of both sexes with at least two years follow-up and at least two EEG recordings in which spike wave indexes (SWI) were calculated and classified as three groups: good response (a decrease of ≥50% in SWI), moderate response (a decrease of <50%), and no response (an increase/no decrease). RESULTS: In 136 patients enrolled, the median interval between first and last EEGs was 35.5 (12-108) months. Median SWI in the first and last EEGs were 39% (7.6-89%) and 0 (0-112%). Good and moderate responses were observed in 26 (19.1%) and 105 (77.2%) patients. No response group included five patients (3.7%). Gender, seizure onset age, psychiatric diseases, seizure characteristics (semiology, duration, and relationship to sleep), last EEG time, and lateralization/localization features in the first EEG did not have a statistically significant effect on the SWI change. SWI change groups were significantly different in the presence of interhemispheric (p= 0.011) and interhemispheric (p < 0.001) generalizations. Phase reversal was significantly higher in no response group (p= 0.029). Valproate was the best suppressor of SWI (p= 0.033). CONCLUSION: Generalization and phase reversal in the first EEG in SLECTS had negative effects on the spike reduction. The most effective ASM in reducing spikes was valproate.