Background/objectivesWilson's disease (WD) is a rare genetic disorder that leads to copper overload, mainly in the liver then, in the brain. Patients with WD often complain about sleep disorders. We aimed to explore them.Patients/methodsSleep complaints and disease symptoms were compared in 40 patients with WD (20 patients with hepatic phenotype matched to 20 neurologic one) and 40 age, sex and BMI matched healthy controls.ResultsPatients with WD had more frequently (32.5 vs 10.0%, p < 0.05) and more severe (10.5 ± 6.0 vs 7.6 ± 4.8, p < 0.01) insomnia than controls and insomnia was more severe in neurologic than hepatic form of the disease (12.25 ± 5.89 vs 8.73 ± 5.8, p < 0.05). Insomnia severity was correlated with the severity of depressive symptoms (r = 0.53, p < 0.001). Compared to controls, patients reported more difficulties staying asleep and more consequences of insomnia on their quality of life. REM sleep behavior disorder was more frequent in WD (20 vs 0%, p = 0.005) than controls. Patients complained more frequently of nycturia (22.8 vs 7.6%, p = 0.003) than controls. Patients did not differ from controls for sleepiness, restless legs syndrome and obstructive sleep apnea syndrome. Patients did not report cataplexia.ConclusionIn patients with WD, insomnia and REM sleep behavior disorder are the two main sleep complaints. Insomnia is more frequent in neurologic than hepatic form of the disease. Severity of insomnia is associated with the severity of depressive symptoms.