Higher body mass index indicated better overall survival in pancreatic ductal adenocarcinoma patients: a real-world study of 2010 patients

BACKGROUND: The association between body mass index (BMI) and the overall survival (OS) of pancreatic ductal adenocarcinoma (PDAC) patients remains controversial and unclear, METHOD: A total of 2010 patients from a high-volume center were enrolled in the study. The OS of PDAC patients was evaluated based on restricted cubic spline (RCS), propensity score (PS) and multivariable risk adjustment analyses. RESULT: BMI was linearly related to the OS (total P = 0.004, nonlinear P = 0.124). BMI was analyzed as categorical data based on X-tile software-defined cutoffs and World Health Organization (WHO)-recommended cutoffs. Adjusted with confounding covariates, higher BMI manifested as a positive prognostic predictor. Furthermore, BMI was proven to be associated with the OS in the 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) vs. Normal(Xtile) vs. Overweight(Xtile): 0.565 vs. 0.474 vs. 0.409; Underweight(WHO) vs. Normal(WHO) vs. Overweight(WHO): 0.613 vs. 0.464 vs. 0.425). CONCLUSION: Among PDAC patients, there was a positive association between BMI and the OS, especially in patients treated with chemotherapy. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12885-021-09056-0.