Reference Values for Weight Loss During 1 Year After Sleeve Gastrectomy: a Multicenter Retrospective Study in Japan

This study aimed to provide reference values for the percentage total weight loss during 1 year after laparoscopic sleeve gastrectomy associated with primary response in Japan.

This multicenter retrospective study comprised 248 patients with severe obesity who underwent laparoscopic sleeve gastrectomy at five institutions in Japan. A percentage total weight loss < 20% at 1 year was defined as primary non-response. Parsimonious predictive models were developed based on the results of multiple regression analyses. A receiver operating characteristic curve analysis was used to assess the discriminative performance for primary non-response.

The median age, initial body mass index, and percentage total weight loss at 1 year were 41 years, 41.4 kg/m², and 30.1%, respectively. There were 28 (11.3%) primary non-responders. For discriminating primary non-responders, the areas under the receiver operating characteristic curve of the parsimonious model and actual percentage of total weight loss at 3 months after laparoscopic sleeve gastrectomy were 0.846 and 0.803, respectively. Cutoffs for the predicted percentage total weight loss using the model and actual value of percentage total weight loss at 3 months attaining 80% sensitivity were 30% and 22%, and those attaining 98% specificity were 22% and 15%, respectively.

Reference values for the percentage total weight loss at 3 months were obtained using the predictive model and actual value of percentage total weight loss at 3 months. Patients at risk for primary non-response can be determined at 3 months with these values, which can help in considering earlier interventions.