Association between tea consumption and gastroesophageal reflux disease: A meta-analysis.

BACKGROUND: Gastroesophageal reflux disease (GERD) is one of the most common digestive system diseases, which is associated with lifestyle and dietary factors. The main mechanism involved in GERD is affected by demographics, lifestyles, and dietary factors. Tea consumption is reported to be associated with GERD, especially in Asian population. However, the effect of tea drinking on GERD risk is still controversial. The aim of this study was to investigate the relationship between tea consumption and the risk of GERD by meta-analysis. METHODS: We searched the published research databases such as PubMed and Embase for studies that were published up to March 2018. The search results were reviewed by 2 authors, and studies that complied with the criteria were selected. Odds ratio (OR) and 95% confidence interval (CI) were used to assess the association between tea consumption and the risk of GERD. RESULTS: Twenty-three articles including 30 studies were included in the meta-analysis. The result of meta-analysis showed that tea drinking had no significant association with the risk of GERD. The odds ratio (OR) and 95% CI were 1.12 and (0.98-1.27). In subgroup analysis based on geographical region, tea consumption can increase the risk of GERD in East Asia (OR = 1.27, 95% CI = 1.07-1.51), while the risk of GERD was decreased in Middle Asia (OR = 0.77, 95% CI = 0.63-0.95). Besides, in the subgroup of study design, there was a significant association between tea intake and the GERD in cross-sectional study. In no symptom subgroup, the risk of GERD was increased (OR = 1.47, 95% CI = 1.11-1.93). CONCLUSIONS: There was no significant relationship between tea consumption and the risk of GERD overall. However, in subgroup analysis, tea drinking may increase the risk of GERD in East Asia and decrease in Middle Asia. To clarify the causality between tea intake and GERD, a more precise study design will be needed.