Hyperbaric Oxygen Therapy Improves Motor Symptoms, Sleep, and Cognitive Dysfunctions in Parkinson's Disease.

Introduction: The aim of the study was to systematically analyze the therapeutic effectiveness of hyperbaric oxygen therapy compared with conventional drug therapy in patients with Parkinson's disease.

Methods: PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang Database searched to the end of March 2023. Two authors independently screened and abstracted data from each trial. The primary outcome measures included the efficacy rate and the Unified Parkinson's Disease Rating Scale III (UPDRS III). Secondary outcome measures included the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Hamilton Depression Scale (HAMD), Minimum Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Hoehn-Yahr staging.

Results: Thirteen studies with a total of 958 participants were included in the meta-analysis. After intervention, the experimental group exhibited a higher treatment efficacy rate compared to the control group (odds ratio = 3.18, 95% confidence interval [95% CI; 1.60, 6.33], p < 0.01), a lower UPDRS III score (mean difference [MD] = -2.96, 95% CI [-4.31, -1.61], p < 0.01), and lower Hoehn-Yahr staging (MD = -0.14, 95% CI [-0.26, -0.02], p < 0.01). The experimental group also outperformed the control group in non-motor symptoms, with higher scores in MoCA, PSQI, and ESS (standardized MD = 0.65, 95% CI [0.45, 0.85], p < 0.01), (MD = -2.52, 95% CI [-2.85, -2.18], p < 0.01), and (MD = -3.30, 95% CI [-3.77, -2.83], p < 0.01), respectively.

Conclusion: Hyperbaric oxygen therapy improves motor function, relieves the severity of the disease, ameliorates cognitive function, and improves sleep quality while alleviating excessive daytime sleepiness in patients with Parkinson's disease. The therapeutic mechanism of hyperbaric oxygen therapy may be related to increased cerebral tissue oxygen content, which contributes to anti-hypoxic, anti-inflammatory, anti-apoptotic, and antioxidant stress.