Assessment of the Effect of Subthalamic Deep Brain Stimulation on Sleep Quality of Parkinson's Disease Patients

Abstract

Aim: To investigate the effects of subthalamic deep brain stimulation (STN DBS) therapy on sleep quality of Parkinson?s Disease (PD) patients and the relationship between sleep, motor symptoms, depression, and adverse effects of dopamine replacement therapies.

Material and methods: A total of 26 PD patients have been included and assessed using various tools both 1 week before and 8 months after the STN DBS therapy. The data collection tools were the Unified Parkinson?s Disease Rating Scale (UPDRS), Beck Depression Inventory (BDI), Montreal Cognitive Assessment (MoCA), Parkinson?s Disease Questionnaire (PDQ-39), Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS) and Polysomnography.

Results: PSQI, ISI, and ESS scores were found to have significantly improved after the STN DBS therapy (p=0.002, p=0.006, p < 0.001, respectively), as were the scores obtained from several PSQI sub-scales, that is, sleep duration, sleep disturbance and daytime dysfunction (p=0.023, p=0.005, p=0.032, respectively). Additionally, Wake Times After Sleep Onset (WASO) (p=0.047) and Rapid Eye Movement (REM) sleep latency values (p=0.005) were found to have decreased after the STN DBS treatment, whereas REM sleep durations (p=0,028) and REM sleep percentages (p=0.007) were found to have increased, after the STN DBS therapy. No correlation was found between the ESS scores and Levodopa Equivalent Dosage (LED) or between the scores obtained from the sleep scales and the scores obtained from the UPDRS and BDI. There was also no correlation between sleep scores and other PD-related factors.

Conclusion: The findings of this study indicated that STN DBS therapy positively affected the PD patients? sleep. This result was attributed to the neuromodulatory effects of the STN DBS independent of the motor symptoms, depression levels, and LED decrease.