Effect of Buspirone on Upper Gastrointestinal Disorders of Gut-Brain Interaction: A Systematic Review and Meta-analysis.

Background/aims: Buspirone shows promise in treating disorders of gut-brain interaction (DGBIs), particularly functional dyspepsia. However, findings have been mixed.

Methods: We systematically searched for prospective studies testing buspirone for any upper gastrointestinal DGBI in 4 databases (Cochrane, PubMed, Scopus, and PsycInfo). The primary outcome was any validated measure of gastrointestinal symptoms. Anxiety, depression and adverse events were secondary outcomes. For randomized controlled trials (RCTs), we performed random-effects meta-analysis of the standardized mean difference (SMD) in post-treatment scores between buspirone and control groups. Risk of bias in RCTs was assessed using the Cochrane Common Mental Disorders Depression Anxiety and Neurosis Group (CCDAN) scale.

Results: Ten studies (n = 283) met inclusion criteria, comprising 5 RCTs, 1 N-of-1 trial, 1 cohort, 1 case series, and 2 case reports. Tolerability of buspirone was good. In meta-analysis, buspirone produced a non-significant improvement in functional dyspepsia/gastroparesis symptoms compared to placebo (SMD = -0.14; 95% CI, -0.44 to 0.17; P = 0.39; I² = 0%; N_studies = 3). Of individual symptoms, buspirone improved bloating severity more than placebo (SMD = -0.41; 95% CI, -0.77 to -0.04; P = 0.03; N_studies = 2) but did not improve post-prandial fullness (P = 0.24, N_studies = 2) or nausea (P = 0.75, N_studies = 2). All RCTs included in the meta-analysis were good quality but most treated for only 4 weeks.

Conclusions: We found that buspirone did not improve functional dyspepsia symptoms more than placebo, though studies were small. Buspirone showed benefit for bloating severity, albeit based on few studies. Larger and longer trials of buspirone, targeting more defined groups such as patients with bloating, are warranted.