Abstract
Psoriasis is a chronic inflammatory skin condition with significant systemic and psychosocial impacts. Emerging evidence suggests a potential link between gut microbiota and psoriasis, prompting growing interest in gut microbiota-targeted therapies (GMTT) as a potential novel treatment strategy. Aims: This study aims to conduct a systematic review and meta-analysis to evaluate the efficacy and safety of GMTT in patients with psoriasis. Methods: PubMed, Embase, Web of Science, Cochrane, CNKI and Wanfang were searched up to May 2024 for randomized controlled trials (RCTs) assessing GMTT for psoriasis. Outcomes included Psoriasis Area and Severity Index (PASI), Dermatology Life Quality Index (DLQI), C-reactive protein (CRP) and adverse events. The risk of bias of the included RCTs was independently assessed using the Cochrane RoB tool. A random-effects model was used to calculate pooled standardized mean differences (SMDs) and 95% confidence intervals (CIs). Sensitivity, subgroup analyses and publication bias analyses were performed to assess the stability of the results and the sources of heterogeneity. Analyses were conducted using Review Manager 5.4 and STATA 15.1. The GRADE approach was used to assess the certainty of evidence. Results: Eight RCTs involving 409 patients were included. GMTT was associated with a modest reduction in PASI scores (SMD = -0.52, 95% CI [-0.98, -0.06], I² = 79%, p = 0.03). Subgroup analyses showed greater efficacy with antibiotic intervention, interventions < 3 months, Asian populations and plaque psoriasis. No significant differences were observed in adverse events (RR = 0.99, 95% CI [0.50, 1.94], I² = 23%, p = 0.97), DLQI or CRP. Funnel plots and Egger’s test indicated no significant publication bias, but sensitivity analysis revealed some instability. Conclusions: GMTT may offer modest benefits for psoriasis symptoms, particularly in specific subgroups. However, larger RCTs are needed to confirm these findings due to current limitations such as small sample sizes and regional biases. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12865-025-00747-y.