BMI trajectories, associations with outcomes and predictors in elderly gastric cancer patients undergoing radical gastrectomy: a prospective longitudinal observation study

Objectives Elderly gastric cancer patients undergoing radical gastrectomy are prone to experience unexpected weight loss. Preoperative weight risk prediction may be a promising way to prevent weight loss and improve prognosis. The objectives of this study were to explore the BMI trajectory of elderly gastric cancer patients one year after surgery, evaluate theirs the association with outcomes, and explore their related predictors, so as to provide evidence for weight management and prognosis improvement. Methods 412 gastric cancer patients were included and recorded BMI at 6 time points. The trajectories of BMI were analyzed by growth mixture modeling, and the associations of BMI trajectories with outcomes as well as their predictors were investigated by regression models. Results We identified 3 classes of BMI trajectories: the “slow-decreasing BMI”, “rapid-decreasing BMI” and “maintaining BMI”. Compared with class1, patients in class 2 were more likely to have a higher frequency of readmission within 1-year( β = 0.59, 95% CI : 0.29, 0.89, P < 0.001) and a higher rate of mortality within 1-year( β = 24.74, 95% CI : 9.60, 63.74, P < 0.001) ; patients in class 3 were more likely to have a higher quality of life ( β =-10.46, 95% CI : -17.70, -3.22, P = 0.005) and fewer readmission times within one year ( β =-0.43, 95% CI : -0.77, -0.09, P = 0.015). Predictors of decreasing BMI trajectories were TNM stage, comorbidity, anxiety, family cohesion and social support( P < 0.05). Conclusions Our findings can provide a basis for screening high-risk elderly gastric cancer patients with poor prognosis, implementing risk stratification, formulating accurate weight management programs and improving prognosis. Implications for Cancer Survivors The results of our study can provide gastric cancer survivors with preoperative risk screening based on predictive factors so that nutritional support and weight management can be implemented in a timely manner to improve prognosis.