Characteristics of the included studies.

Background and objectives
The potential association between rosacea and a heightened prevalence of Helicobacter pylori (HP) infection has been previously suggested. However, existing studies offer inconsistent results. This systematic review and meta-analysis aimed to elucidate the relationship between rosacea and HP infection.
Methods
We conducted comprehensive searches of PubMed, Embase, and Web of Science databases to identify relevant observational studies for our investigation. We utilized the random-effects model to aggregate the data to address the potential influence of heterogeneity among the studies on the outcome.
Results
Our analysis incorporated twenty-five datasets from 23 case-control and cross-sectional studies, encompassing 51,054 rosacea patients and 4,709,074 controls without skin disease. The pooled results revealed a significantly higher prevalence of HP infection in individuals with rosacea compared to controls (odds ratio [OR]: 1.51, 95% confidence interval [CI]: 1.17–1.95, p<0.001; I2 = 79%). Subgroup analysis indicated an increased prevalence of HP infection in rosacea studies that utilized one (OR: 1.72, 95% CI: 1.11–2.66, p = 0.02; I2 = 76%) or more tests for HP infection (OR: 2.26, 95% CI: 1.29–3.98, p = 0.005; I2 = 56%). However, this association was not observed in population-based studies that determined HP infection based on prescription records for HP eradication drugs (OR: 0.90, 95% CI: 0.76–1.07, p = 0.024; I2 = 54%).
Conclusion
Rosacea may be significantly associated with a higher prevalence of HP infection. High-quality prospective studies with delicately controlled confounding factors are needed to determine if HP infection is a risk factor for rosacea.