Higher BMI Indicated Better Overall Survival Prognosis of Pancreatic Ductal Adenocarcinoma: A Real-World Study Based on 2,010 Cases

Abstract Background: Whether body mass index (BMI) was associated with the overall survival (OS) of pancreatic ductal adenocarcinoma (PDAC) remained controversial and uncertain. Method: A total of 2,010 patients from single high-volume center were enrolled in the study. OS of PDAC patients was evaluated based on restricted cubic spline (RCS), propensity score (PS) and multivariable risk adjustment analyses. Result: BMI was discovered linear related with OS (total P =0.004, non-linear P =0.124). BMI was analyzed as categorical data based on X-tile software defined cutoffs and World Health Organization (WHO) recommended cutoffs, respectively. Adjusted with confounding covariates, higher BMI manifested as a positive prognostic predictor. ( P Xtile =0.003, P WHO =0.002) Furtherly, BMI was proven associated with OS in PS analysis. (Underweight Xtile vs. Normal Xtile P=0.003, Overweight Xtile vs. Normal Xtile P=0.019; Underweight WHO vs. Normal WHO P<0.001, Overweight WHO vs. Normal WHO P=0.024). It was also revealed that patients with higher BMI benefitted more from chemotherapy.(adjusted hazard ratio (aHR): Underweight Xtile : 0.565 (0.389-0.819), Normal Xtile : 0.474 (0.395-0.567), Overweight Xtile : 0.409 (0.337-0.496); Underweight WHO : 0.613 (0.401-0.940), Normal WHO : 0.464 (0.387-0.557), Overweight WHO : 0.425 (0.353-0.512)). Conclusion: Among PDAC patients, higher BMI manifested as a favorable OS indicator, and the protective impact was probably based on chemotherapy administration. Patients with higher BMI were also observed with more chemotherapy administration and more OS benefits from chemotherapy.