(Losito E, et al. 2017) Of 33 patients with Dravet syndrome older than eleven years in a French cohort, 26 experienced a switch from mainly daytime seizures to mainly sleep/nocturnal (S/N) seizures between age 4 and age 11. The S/N seizures were usually brief, often occurred in clusters of 2-15 per night, and were often focal with a tonic, tonic-vibratory and tonic-clonic pattern. Many of those patients had frontal and central anomalies on their EEG. The authors suggest further study of the possible relationship between this shifting seizure pattern and the high rate of SUDEP in Dravet syndrome.

Losito E, Kuchenbuch M, Chemaly N, Laschet J, Chiron C, Kaminska A, Nabbout R. Age-related “Sleep/nocturnal” tonic and tonic clonic seizure clusters are underdiagnosed in patients with Dravet Syndrome. Epilepsy Behav. 2017 Jul 3;74:33-40. doi: 10.1016/j.yebeh.2017.05.037. [Epub ahead of print] PubMed PMID: 28683344.