Relationship between alcohol consumption and the risks of liver cancer, esophageal cancer, and gastric cancer in China: Meta-analysis based on case–control studies

OBJECTIVE: : To study the correlation between alcohol consumption and the risks of liver, esophageal squamous cell carcinoma (ESCC), and gastric cancers in China mainland by meta-analysis. METHODS: : We systematically searched electronic databases to identify the case–control studies that reported the association between alcohol consumption and the risks of liver, ESCC, and gastric cancers from January 1, 2010 to April 1, 2020. The Newcastle–Ottawa Scale (NOS) was used to evaluate literature quality, and I(2) analyzes were used to evaluate the heterogeneity. RESULTS: : A total of 2855-related studies were retrieved. After conditional screening, we included 26 case–control studies for meta-analysis. Meta-analysis showed that alcohol consumption was associated with increased risks of liver, ESCC, and gastric cancers (total pooled odds ratio [OR], 1.83; 95% confidence interval [CI], 1.58–2.11; liver cancer OR, 1.83; 95% CI, 1.39–2.40; ESCC OR, 2.00; 95% CI, 1.66–2.40; gastric-cancer OR, 1.54; 95% CI, 1.10–2.15). Subgroup analysis results showed that the pooled ORs of volume of alcohol consumed, years of drinking, age of starting drinking, and drinking status were 1.71 (95% CI, 1.36–2.15), 1.65 (95% CI, 1.33–2.06), 1.38 (95% CI, 0.98–1.94), and 2.00 (95% CI, 1.42-2.81), respectively. Regression analysis showed that geographical region was a source of heterogeneity. CONCLUSION: : Alcohol consumption increased the risks of liver cancer, ESCC, and gastric cancers in China. Volume of alcohol consumed, years of drinking, age of starting drinking, and drinking status were all significant factors for these risks.