S3151 Efficacy of Mirtazapine in Patients With Functional Dyspepsia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Introduction: Functional dyspepsia (FD) is a prevalent gastrointestinal disorder, yet current treatment options offer limited relief. Recent studies suggest that mirtazapine may alleviate symptoms in patients with FD. This systematic review and meta-analysis aimed to assess the effectiveness and safety of mirtazapine for treating patients with FD. Additionally, we conducted subgroup analysis based on prior history of weight loss. Methods: We systematically searched PubMed, Embase, and Cochrane Library databases for randomized controlled trials (RCTs) comparing mirtazapine versus placebo or standard treatment in patients with FD. Random-effects model was used to calculate the pooled mean differences (MD) for continuous outcomes and risk ratios (RR) for binary outcomes, with respective 95% confidence intervals (CI). We used R for statistical analyses. Results: This meta-analysis included 3 RCTs involving 214 patients aged 18 to 70 years with FD. Of these, 94 patients experienced weight loss following their FD diagnosis. The studies used the Rome III and IV criteria for inclusion. Compared with placebo and standard treatment, mirtazapine significantly decreased Nepean Dyspepsia Index (NDI) (MD -5.21; 95% CI -6.45 to -3.96), Visceral Sensitivity Index (VSI) (MD -7.15; 95% CI -9.49 to -4.80), and Dyspepsia Symptom Severity (DSS) score (MD -2.52; 95% CI -3.92 to -1.11). Mirtazapine also significantly increased body weight (MD 7.81 kg; 95% CI 3.34 to 12.28 kg). There was no significant difference in the risk of adverse events between the groups (RR 2.53; 95% CI 0.34 to 19.01). The subgroup analysis based on prior history of weight loss showed consistent results with overall analysis. Conclusion: In patients with FD, mirtazapine was associated with significant reductions in NDI, VSI, and DSS scores, as well as weight gain. These findings suggest mirtazapine is more suitable for FD patients with weight loss.