The importance of weight stabilization amongst those with overweight or obesity: Results from a large health care system

Data on patterns of weight change among adults with overweight or obesity are minimal. We aimed to examine patterns of weight change and associated hospitalizations in a large health system, and to develop a model to predict 2-year significant weight gain. Data from the Duke University Health System was abstracted from 1/1/13 to 12/31/16 on patients with BMI ≥ 25 kg/m² in 2014. A regression model was developed to predict patients that would increase their weight by 10% within 2 years. We estimated the association between weight change category and all-cause hospitalization using Cox proportional hazards models. Of the 37,253 patients in our cohort, 59% had stable weight over 2 years, while 24% gained ≥ 5% weight and 17% lost ≥ 5% weight. Our predictive model had reasonable discriminatory capacity to predict which individuals would gain ≥ 10% weight over 2 years (AUC 0.73). Compared with stable weight, the risk of hospitalization was increased by 37% for individuals with > 10% weight loss [adj. HR (95% CI): 1.37 (1.25,1.5)], by 30% for those with > 10% weight gain [adj. HR (95% CI): 1.3 (1.19,1.42)], by 18% for those with 5–10% weight loss [adj. HR (95% CI): 1.18 (1.09,1.28)], and by 10% for those with 5–10% weight gain [adj. HR (95% CI): 1.1 (1.02,1.19)]. In this examination of a large health system, significant weight gain or loss of > 10% was associated with increased all-cause hospitalization over 2 years compared with stable weight. This analysis adds to the increasing observational evidence that weight stability may be a key health driver.