Brief CommunicationElectroencephalographic patterns during sleep in children with chromosome 15q11.2-13.1 duplications (Dup15q)

- The objective was to define EEG sleep patterns of children with Dup15q syndrome.
- Alpha-delta sleep occurred in 14 children (33%, nine with idic15).
- Electrical status epilepticus in sleep found in 15 children (35%, all with idic15)
- High amplitude, sharp fast activity found in 15 children (35%, 14 with idic15)
- This is the first report of sleep EEG patterns in children with Dup15q syndrome.

Our objective was to define the EEG features during sleep of children with neurodevelopmental disorders due to copy number gains of 15q11-q13 (Dup15q). We retrospectively reviewed continuous EEG recordings of 42 children with Dup15q (mean age: eight years, 32 with idic15), and data collected included background activity, interictal epileptiform discharges, sleep organization, and ictal activity. Three patterns were recognized:Pattern 1: Alpha-delta sleep was noted in 14 children (33%), not associated with any clinical changes.Pattern 2: Electrical status epilepticus in sleep was noted in 15 children (35%), all diagnosed with treatment-resistant epilepsy. Thirteen of the 15 children had clinical seizures.Pattern 3: Frequent bursts of high amplitude bifrontal predominant, paroxysmal fast activity (12-15 Hz) during non-REM sleep was noted in 15 children (35%). All 15 children had treatment-resistant epilepsy.This is the first report of electroencephalographic patterns during sleep of children with Dup15q reporting alpha-delta rhythms, CSWS, and high amplitude fast frequencies. Alpha-delta rhythms are described in children with dysautonomia and/or mood disorders and CSWS in children with developmental regression. The significance of these findings in cognitive function and epilepsy for the children in our cohort needs to be determined with follow-up studies.