Prediagnostic adult body mass index change and esophageal adenocarcinoma survival

BACKGROUND: We examined whether body mass index (BMI) changes in adulthood, prior to disease onset, are associated with overall survival among esophageal adenocarcinoma patients. METHODS: We included 285 histologically confirmed patients with a complete baseline BMI questionnaire. Using extended Cox regression models, we obtained adjusted hazard ratios (HRs) for the associations between overall survival and BMI at diagnosis, BMI 6 months before diagnosis, self‐reported average adult BMI, and ΔBMI (BMI 6 months before diagnosis minus average adult BMI), categorized into tertiles <0 kg/m(2) (BMI loss), ≥0 and <1.25 kg/m(2) (stable BMI), and ≥1.25 kg/m(2) (BMI gain). We also assessed interaction between ΔBMI and average adult BMI (≥ kg/m(2) versus <27.5 kg/m(2)) with overall survival. RESULTS: Body mass index at diagnosis >25 and <35 kg/m(2) was associated with better overall survival. Compared to patients with stable BMI in adulthood, patients who gained BMI throughout adulthood had 1.68 times the all‐cause hazard of death (95% CI: 1.17‐2.43; P < .01), independent of diagnosis BMI and percent weight loss 6 months before diagnosis. Compared to patients with average adult BMI < 27.5 who maintained stable adult BMI, patients with average adult BMI ≥ 27.5 kg/m(2) who gained BMI had the worst survival (HR = 3.05; 95% CI 1.62‐5.72; P < .01). CONCLUSION: Body mass index gain in adulthood is associated with poor overall survival, and maintaining a normal body weight throughout adulthood is associated with the best overall survival among esophageal adenocarcinoma patients, independent of BMI at diagnosis.