Electroclinical and behavioral outcomes of add-on ethosuximide in children with developmental and epileptic encephalopathy with spike-wave activation in sleep (D/EE-SWAS): A prospective observational study.

The median age at diagnosis of D/EE-SWAS was 6 years (range 1-10 years).

Electroencephalographic improvement occurred in 29/39 (74.4%), including complete normalization in 8/39 (20.5%).

Complete electroencephalographic normalization was more frequent in idiopathic compared with structural D/EE-SWAS (41.2%vs 4.5%, p = 0.01).

Significant improvement was observed across Strengths and Difficulties Questionnaire domains, including total difficulties, emotional symptoms, hyperactivity, conduct problems, peer problems, and impact scores (all p < 0.001).