Efficacy of cognitive behavioral therapy for insomnia comorbid to Parkinson's disease: A focus on psychological and daytime functioning with a single-case design with multiple baselines.

OBJECTIVE: To test the efficacy of cognitive behavioral therapy for insomnia (CBT-i) in Parkinson's Disease (PD) and to evaluate its impact on indices of daytime and psychological functioning. METHOD: Fifteen patients with insomnia disorder (ID) comorbid to PD were enrolled in a single-case design with multiple baselines. Total wake time, sleep efficiency, and daytime sleepiness were recorded on a sleep diary. Self-reported measures of insomnia, anxiety and depressive symptoms, health-related quality of life, and psychological variables perpetuating ID were completed. All patients also underwent a clinical interview for ID diagnosis. RESULTS: CBT-i was associated with significant changes in sleep variables and ID criteria. Significant positive treatment-related effects were also noted for all indices of daytime and psychological functioning, and for variables perpetuating ID. All of these improvements were well maintained at 3-month follow-up. CONCLUSION: CBT-i is a promising therapeutic avenue for patients with PD.