Metabolic effects of bariatric surgery on patients with type 2 diabetes: a population-based study

Abstract

Background: Bariatric surgery among patients with obesity and type 2 diabetes (T2D) can induce complete remission. However, it remains unclear whether sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) has better T2D remission within a population-based daily practice.

Objectives: To compare patients undergoing RYGB and SG on the extent of T2D remission at the 1-year follow-up.

Setting: Nationwide, population-based study including all 18 hospitals in the Netherlands providing metabolic and bariatric surgery.

Methods: Patients undergoing RYGB and SG between October 2015 and October 2018 with 1 year of complete follow-up data were selected from the mandatory nationwide Dutch Audit for Treatment of Obesity (DATO). The primary outcome is T2D remission within 1 year. Secondary outcomes include ≥20% total weight loss (TWL), obesity-related co-morbidity reduction, and postoperative complications with a Clavien-Dindo (CD) grade ≥III within 30 days. We compared T2D remission between RYGB and SG groups using propensity score matching to adjust for confounding by indication.

Results: A total of 5015 patients were identified from the DATO, and 4132 (82.4%) had completed a 1-year follow-up visit. There were 3350 (66.8%) patients with a valid T2D status who were included in the analysis (RYGB = 2623; SG = 727). RYGB patients had a lower body mass index than SG patients, but were more often female, with higher gastroesophageal reflux disease and dyslipidemia rates. After adjusting for these confounders, RYGB patients had increased odds of achieving T2D remission (odds ratio [OR], 1.54; 95% confidence interval [CI], 1.14-2.1; P < .01). Groups were balanced after matching 695 patients in each group. After matching, RYGB patients still had better odds of T2D remission (OR, 1.91; 95% CI, 1.27-2.88; P < .01). Also, significantly more RYGB patients had ≥20%TWL (OR, 2.71; 95% CI, 1.96-3.75; P < .01) and RYGB patients had higher dyslipidemia remission rates (OR, 1.96; 95% CI, 1.39-2.76; P < .01). There were no significant differences in CD ≥III complications.

Conclusion: Using population-based data from the Netherlands, this study shows that RYGB leads to better T2D remission rates at the 1-year follow-up and better metabolic outcomes for patients with obesity and T2D undergoing bariatric surgery in daily practice.

Keywords: Bariatric surgery; Population-based; Propensity score matching; Roux-en-Y gastric bypass; Sleeve gastrectomy; Type 2 diabetes.