Pre-intervention clinical determinants and measured β-cell function as predictors of type 2 diabetes remission after Roux-en-Y gastric bypass surgery

Background: Bariatric surgery results in improved glycemic control in individuals with type 2 diabetes. Single and clusters of clinical determinants have been identified as pre-surgery predictors of post-surgery diabetes remission. Our goal was to assess if the addition of measured pre-operative ß-cell function would improve established clinical models of prediction of diabetes remission.

Methods: Pre-surgery clinical characteristics, metabolic markers, and ß-cell function after oral and intravenous (IV) glucose challenges were assessed in 73 individuals with severe obesity and type 2 diabetes and again one year after gastric bypass surgery. Single and multivariate analyses were conducted with pre-operative variables to determine best predictive models of remission.

Results: Pre-surgery ß-cell glucose sensitivity, a surrogate of ß-cell function, was negatively correlated with known diabetes duration, HbA1c, insulin use, and the diabetes remission scores DiaRem and Ad-DiaRem (all p <0.001). Measured ß-cell function after oral glucose was 1.6-fold greater than after IV glucose challenge, and more strongly correlated with pre-operative clinical and metabolic characteristics. The addition of pre-operative ß-cell function to clinical models containing well-defined diabetes remission scores did not improve the model’s ability to predict diabetes remission post-RYGB.

Conclusions: The addition of measured β-cell function does not add predictive value to defined clinical models of diabetes remission one year after surgical weight loss.