Objectives Impulsive-compulsive behaviours (ICBs) in Parkinson's disease (PD) have been anecdotally linked with impaired sleep. The authors investigate measures of sleep in PD patients with and without ICBs, and in healthy controls.

Methods The authors compare Parkinsonian features, measures of depression, anxiety and mania, and sleep disturbance in 30 PD patients with ICBs (PD+ICB), 62 PD patients without ICBs (PD−ICB) and 48 healthy controls.

Results PD+ICB patients had a younger age of PD onset, took more dopamine replacement therapy (DRT) and had worse sleep, and elevated anxiety, depression and mania scores. Using multiple linear regression analyses, the total anxiety and depression scores, and presence of ICBs were the only variables associated with poorer sleep in PD.

Conclusions PD+ICB patients may show enhanced psychomotor effects of DRT that may in turn contribute to poor sleep quality. Sleep disturbance should be specifically queried in PD+ICB patients.