Association between body mass index and risk of gastric cancer by anatomical and histological subtypes in over 500,000 East and Southeast Asian cohort participants
Menée en Asie auprès de 538 835 personnes, cette étude internationale analyse l'association entre l'indice de masse corporelle et le risque de cancer gastrique (8 997 cas)
Background: This study was performed to investigate the association between body mass index (BMI) and gastric cancer (GC) in East and Southeast Asia where most of GC is non-cardia GC. Methods: Based on 8,997 GC cases among the Asia Cohort Consortium participants from China, Japan, Korea, and Singapore (N=538,835), we assessed GC risk according to BMI by calculating hazard ratios (HRs) and 95% confidence intervals (CIs) using the Cox proportional hazard regression model. Results: A U-shaped associations between BMI and GC risk were observed. GC risks in underweight group (<18.5 kg/m2) and in obesity group (≥27.5 kg/m2) were higher than reference BMI group (23-24.9 kg/m2) (HR=1.15, 95% CI 1.05-1.25 for underweight; HR=1.12, 95% CI 1.03-1.22 for obesity, respectively). The associations of underweight and obesity with GC risk were consistent in the analyses for non-cardia GC, intestinal type GC, and late onset GC. No significant association of underweight and obesity with the risk of cardia GC, diffuse type GC, and early onset GC was observed. Additionally, we found that the U-shaped association between BMI and GC risk remained in non-smokers, while only underweight was related to increased GC risk in smokers. Conclusions: BMI has a U-shaped association with GC risk in East and Southeast Asian population, especially for the non-cardia GC, intestinal type GC, and late onset GC. Impact: Future studies with consideration of anatomical location and histology of GC are needed to establish the association of underweight as well as obesity with GC risk.