Acupuncture for Parkinson's disease-related constipation: A systematic review and meta-analysis

Introduction: The hazard of Parkinson's disease-related constipation (PDC) cannot be ignored. Acupuncture has the potential to become a mainstream treatment option for PDC. This review aimed to investigate the effect of acupuncture on PDC, which might provide evidence-based recommendations for clinical application. Methods: Six databases were searched for randomized controlled trials (RCTs) about acupuncture for PDC. The primary outcome was response rate. The secondary outcomes were rectal resting pressure, anal resting pressure, anal maximum contraction pressure, rectal sensation threshold, rectal maximum tolerable volume, the Constipation Scoring System (CSS) score, the Patient Assessment of Constipation Quality of Life (PAC-QOL) score, and adverse events (AEs). Results: Eight trials involving 591 participants were included. The methodological quality was generally low. A significant difference was found in response rate when comparing acupuncture with medicine (95 %CI= 1.09 to 1.54, P = 0.003) or blank control (95 %CI= 1.04 to 1.74, P = 0.02), while no significant difference was observed when comparing acupuncture + medicine with medicine. Acupuncture + medicine did have a significant effect on rectal resting pressure, anal resting pressure, anal maximum contraction pressure, rectal sensation threshold and rectal maximum tolerable volume when compared with medicine, while no significant effect was found when acupuncture was compared with medicine. A significant difference was found in the CSS score when acupuncture was compared with blank and in the PAC-QOL score when acupuncture was compared with sham or blank, while no significant difference was found in the PAC-QOL score when acupuncture was compared with medicine. One study reported mild AEs. Conclusions: Acupuncture might be an effective treatment for PDC. Due to the limited quality of evidence, high-caliber and multi-center RCTs with large sample sizes should be carried out. (PROSPERO ID is CRD42023422102)