Predictors of type 2 diabetes remission in patients with morbid obesity after bariatric surgery

Background

Bariatric surgery is a highly effective method of type 2 diabetes (T2D) treatment in patients with morbid obesity, but surgical outcomes are variable: some patients do not achieve remission of T2D, others may have insufficient weight loss or subsequent weight regain. Existing models for predicting diabetes remission are not without limitations due to sample heterogeneity, differences in types of surgical interventions, and cohort sizes. Therefore, new prognostic models are needed.

Aim

To determine predictors of T2D remission in patients with morbid obesity within a year after Mini-Gastric Bypass (MGB) or Single Anastomosis Sleeve Ileal Bypass (SASI).

Materials And Methods

A single-center retrospective study included 112 patients with T2D and morbid obesity who underwent either MGB ( n =86) or SASI ( n =26). The status of T2D remission was assessed for 12 months after surgery. Covariate-adjusted logistic regression, Cox regression analysis, and ROC analysis were used to analyze remission predictors.

Results

Remission of T2D within one year after surgery was achieved in 83 (74%) patients. No insulin therapy before surgery (OR=6.27, p <0.001), glycated hemoglobin (HbA 1c , OR=0.5, p <0.001), fasting and 2-hour post-breakfast C-peptide (OR=1.52, p =0.023 and OR=1.21, p =0.041, respectively), and estimated glucose disposal rate (eGDR, OR=1.83, p =0.001) were predictors of remission in logistic regression analysis after adjustment for age, sex, body mass index, and type of operation. In Cox regression analysis, these factors, as well as diabetes duration and C-reactive protein (CRP) level, predicted faster onset of remission within the first year after surgery. The ROC analysis identified the following cut-off points of predictors: diabetes duration <7 years ( p =0.021); HbA 1c <7.5% ( p <0.001); fasting C-peptide >4 ng/mL ( p =0.003); postprandial C-peptide >6.5 ng/mL ( p <0.001); eGDR >1.4 mg/kg/min ( p =0.043); CRP >6.4 mg/L ( p =0.045). A prognostic model based on the identified predictors was developed (AUC=0.92 [95% CI 0.82–0.99], overall accuracy=83% [95% CI 64–94%]).

Conclusion

Achieving remission of T2D within one year after bariatric surgery (MGB, SASI) is associated with a shorter duration of T2D, absence of insulin therapy before surgery, lower preoperative HbA 1c levels, higher fasting and postprandial C-peptide levels, as well as higher preoperative insulin sensitivity (eGDR) and CRP levels.