Sleep architecture and qEEG patterns in PME type 1 diagnosis.

Unverricht-Lundborg disease (ULD) is a rare, progressive myoclonic epilepsy for which no disease-modifying treatments currently exist. Disease biomarkers are critically needed to guide prognosis and monitor therapeutic response. We present a case highlighting progressive deterioration of sleep architecture as a potential marker of disease progression in ULD. Quantitative EEG (qEEG) analysis over serial recordings demonstrated a gradual decline in hallmark features of non-rapid eye movement sleep, including sleep spindles and K-complexes. Over time, these sleep-specific graphoelements became nearly absent, rendering sleep EEG patterns indistinguishable from wakefulness. This loss of sleep architecture occurred in parallel with worsening motor and cognitive function. These findings suggest that sleep EEG abnormalities may reflect underlying cortical dysfunction and could serve as an early, objective indicator of neurodegeneration in ULD. Further prospective studies are warranted to validate qEEG as a noninvasive biomarker for disease monitoring and to explore its potential role in clinical trials.