Association between sleep disturbances and pain subtypes in Parkinson's disease.

Objective: To explore the influence of sleep disturbances on the various pain subtypes experienced by patients with Parkinson's disease (PD).

Methods: A cohort of eighty-eight patients with PD-related pain was recruited for this study. Their demographic and clinical features, including age, disease duration, levodopa equivalent daily dose (LEDD), and scores on the Unified Parkinson's Disease Rating Scale-III (UPDRS III), Hoehn-Yahr Scale (H&Y), Pittsburgh Sleep Quality Index (PSQI), King's Parkinson's disease Pain Scale (KPPS), visual analog scale (VAS), Mini-Mental State Examination (MMSE), activities of daily living scale (ADL), Hamilton Depression Rating Scale (HAMD), and Hamilton Anxiety Rating Scale (HAMA), were recorded.

Results: The prevalence of sleep disorders was 76.1% in patients with PD-related pain. Among these patients, the group of poor sleep had more severe motor symptoms, more anxiety and depression symptoms, lower functional independence, and experienced more pain, such as musculoskeletal pain, chronic pain, fluctuation related pain, nocturnal pain, and discoloration/edema/swelling (p < 0.05). In addition, PSQI scores correlated positively with the scores of all 7 domains in KPPS (p < 0.05). H&Y stage and PSQI were significant independent variables explaining 50.0% of the variance in KPPS scores.

Conclusions: Sleep disturbance showed an association with pain in PD patients and may have a greater effect on some certain subtypes of PD-related pain than others.