S2121 Impact of Helicobacter pylori Eradication on Ghrelin Levels and BMI: Single-Arm Meta-Analysis With Leave-One-Out Sensitivity Analysis

Introduction: A persistent Helicobacter pylori infection suppresses the production of gastric ghrelin, which may restrict appetite and growth. Although eradication therapy may increase endocrine production, its effect on body weight is still up for debate, which feeds worries about obesity and hopes for better nutrition. We combined longitudinal studies that assessed body-mass index (BMI) and circulating ghrelin levels before and after confirmed eradication to provide clarity. Methods: A systematic search of MEDLINE, Embase, Scopus and CENTRAL were searched for trials or cohorts reporting paired pre/post ghrelin or BMI ≥4 weeks after confirmed eradication through May 2025. Two reviewers screened, extracted means ±SD and judged bias with RoB 2 or Newcastle-Ottawa. Pooled mean differences were generated with DL random effects model; heterogeneity was summarized by τ² and I². Forest plots displayed effect sizes, while leave-one-out plots located influential studies. Data analysis was done using R (v4.4.3) with 'meta' package. Results: Six studies, comprising 1,002 participants, assessed changes in ghrelin levels and BMI following H. pylori eradication. For BMI change, the random-effects model showed a non-significant mean difference (MD) of 0.79 (95% confidence interval [CI]: -0.52 to 2.10) with high heterogeneity (I² = 84.4%, τ² = 1.66). Leave-one-out analysis revealed that excluding Choe et al. (2007) reduced heterogeneity to 0% and yielded an MD of 0.28 (95% CI: -0.04 to 0.61). For ghrelin levels, eradication significantly increased levels with an MD of 163.60 (95% CI: 111.19 to 216.01) but showed extreme heterogeneity (I² = 99.9%, τ² = 4191.47). Sensitivity analysis found all studies contributed to high heterogeneity except Lane et al (2011) whose exclusion lowered I² to 83.9% and resulted in an MD of 3.42 (95% CI: -2.80 to 9.64). Conclusion: These results suggest H. pylori eradication raises ghrelin and may modestly raise BMI, but heterogeneity limits firm conclusions. The rebound confirms infection suppression yet seldom yields clinically relevant weight gain. Pediatric studies showed small increases, whereas adult community trials and dialysis cohorts were weight-neutral, explaining most dispersion. Leave-one-out influence plots demonstrated that removing such context-specific outliers normalized heterogeneity and centered BMI effects on null. Clinically, eradication seems to restore endocrine balance without promoting obesity, though longer, better-powered trials across diverse metabolic profiles are needed.