Altered Sleep Patterns in Wilson's Disease Including Shortened REM Latency

Background and Clinical Significance: Wilson's disease (WD) is an inherited, multisystem disorder of copper metabolism, resulting in pathological copper accumulation in various tissues (predominantly the liver and brain) and leading to secondary organ damage and corresponding clinical manifestations. Sleep disorders are frequent in neurodegenerative disorders, but remain underdiagnosed and poorly characterized in WD. Case presentation: We describe the case of a 51-year-old patient with WD presenting predominantly with neurological symptoms, who underwent routine video-polysomnography (v-PSG). The examination revealed shortened sleep latency, reduced rapid eye movement (REM) sleep latency, and sleep fragmentation-features of sleep architecture frequently observed in narcolepsy. These abnormalities worsened at follow-up despite the introduction of anti-copper treatment and concomitant neurological improvement. However, the patient did not report clinical symptoms of narcolepsy, and none were confirmed by the evaluating sleep specialist. Conclusions: This case highlights that sleep disorders (SDs) are common in patients with WD. Such patients may experience a wide range of SDs, and anti-copper treatment may improve sleep quality in addition to alleviating neurological symptoms. Narcolepsy is a rare but possible manifestation of SDs in WD. Therefore, whenever symptoms suggestive of sleep disturbances occur, WD patients should be referred to a sleep specialist, as accurate diagnosis and targeted treatment may profoundly improve quality of life, daily functioning, and long-term disease management.