The gut-skin axis in psoriasis: Evidence-based insights from a meta-analysis on probiotics-synbiotics-mediated microbiota interventions

Psoriasis, a chronic immune-mediated skin condition, has been intricately linked to gut microbiota dysbiosis through the gut-skin axis. This meta-analysis synthesizes data from 15 randomized controlled trials encompassing 1,423 participants to evaluate the efficacy of gut microbiota interventions—probiotics and synbiotics—in psoriasis management. The findings reveal that probiotics significantly improved the Psoriasis Area and Severity Index (PASI) (Mean Difference [MD]: -4.05, 95% CI: -6.73 to -1.38; p < 0.0001) and Dermatology Life Quality Index (DLQI) (MD: -5.74, 95% CI: -11.45 to -0.03; p = 0.0001), outperforming synbiotics and systemic pharmacological therapies such as anti-TNF-α and anti-interleukin agents. Notably, probiotics demonstrated superior systemic anti-inflammatory (TNF-α and IL-17) and immunomodulatory responses, and enhanced gut barrier integrity. This study highlights probiotics as a promising adjunct or alternative therapy, paving the way for integrative treatment strategies that address psoriasis's multifaceted pathophysiology. Future research should focus on long-term efficacy and molecular mechanisms to optimize outcomes. These findings could redefine therapeutic paradigms, offering a cost-effective and accessible solution for millions of psoriasis patients worldwide. • Probiotics significantly reduce psoriasis severity and improve quality. • Gut microbiota modulation outperforms systemic drugs in psoriasis. • Probiotics show strong anti-inflammatory and immunomodulatory effects. • Synbiotics offer benefits but are less effective than probiotics.