1688-P: Type 2 Diabetes Remission after Metabolic and Bariatric Surgery—A Systematic Review and Meta-analysis Comparing Less Obese and Severely Obese Individuals

Introduction & Objective: Metabolic and bariatric surgery (MBS) effectively induces diabetes remission in severely obese individuals. However, its impact on those with less severe obesity remains uncertain. We investigated type 2 diabetes remission after MBS based on preoperative body mass index (BMI).

Methods: We searched MEDLINE, Embase, and the Cochrane Library databases up to May 2021, focusing on diabetes remission concerning BMI without restricting to intervention-comparison studies. We included clinical trials, cohort studies, and consecutive case series involving ≥50 individuals with type 2 diabetes who underwent MBS and reported diabetes remission. Studies were categorized by preoperative BMI (<35 kg/m² or ≥35 kg/m²). The primary outcome was diabetes remission (HbA_1c <6.5% without antidiabetic medication) at different post-surgery intervals, with analysis of HbA_1c and BMI changes. We used meta-regression for between-group comparisons and assessed potential bias.

Results: Eighty-one studies were included (23 with BMI <35 kg/m², 58 with BMI ≥35 kg/m²). At 12 months, diabetes remission rates were 0.59 (95% CI 0.49 to 0.70) for BMI <35 kg/m², and 0.61 (0.55 to 0.67) for BMI ≥35 kg/m². No significant between-group differences were observed at 12 months (adjusted weighted mean difference [WMD] −0.01, 95% CI −0.14 to 0.12), 24 months (adjusted WMD −0.04, 95% CI −0.29 to 0.21), 36 months (adjusted WMD 0.00, 95% CI −0.22 to 0.23), and ≥60 months (adjusted WMD −0.02, 95% CI −0.25 to 0.22). Achieved HbA_1c levels were comparable, but BMI remained higher in those with BMI ≥35 kg/m².

Conclusions: Our study demonstrates that diabetes remission after MBS is similar between individuals with BMI <35 kg/m² and BMI ≥35 kg/m² over the long-term follow-up.