Impact of Smoking and Alcohol Consumption on Early-Onset Gastric Cancer Development in Young Koreans: A Population-Based Study

Abstract

Purpose: Although smoking and alcohol consumption are known risk factors for gastric cancer (GC), studies assessing their effects on early-onset GC are limited. In this nationwide, population-based, prospective cohort study, we assessed the effects of smoking and alcohol consumption on early-onset GC in patients aged <50 years. Materials and Methods: We analyzed data of patients aged 20–39 years who underwent cancer and general health screening in the Korean National Health Screening Program between 2009 and 2012. We calculated the adjusted hazard ratios (aHR) and 95% confidence intervals (CI) for GC incidence until December 2020. Results: We enrolled 6,793,699 individuals (men:women=4,077,292:2,716,407) in this cohort. The mean duration of follow-up was 9.4 years. During follow-up, 9,893 cases of GC (men:women=6,304:3,589) were reported. Compared with the aHRs (95% CI) of never-smokers, those of former and current-smokers were 1.121 (1.044–1.205) and 1.282 (1.212–1.355), respectively. Compared with the aHRs (95% CI) of non-consumers, those of low-moderate-and high-risk alcohol consumers were 1.095 (1.046–1.146) and 1.212 (1.113–1.321), respectively. GC risk was the highest in current-smokers and high-risk alcohol consumers (1.447 [1.297–1.615]). Interestingly, alcohol consumption and smoking additively increased the GC risk in men but not in women (Pinteraction=0.002). Conclusion: Smoking and alcohol consumption are significant risk factors for early-onset GC in young Koreans. Further studies are needed to investigate sex-based impact of alcohol consumption and smoking on GC incidence in young individuals.