Shedding more than weight: Metabolic and bariatric surgery and the journey to insulin independence in insulin-treated type 2 diabetes

Type 2 diabetes (T2D) imposes a significant health burden, necessitating lifelong pharmacological interventions, with insulin being one of the cornerstone therapies. However, these regimens are associated with health risks and psychological stressors. This study aimed to examine the rates of insulin-treated T2D remission and cessation or reduction in the dosage of insulin therapy after metabolic and bariatric surgery (MBS). This was a retrospective analysis of patients with a preoperative diagnosis of insulin-treated T2D who underwent primary laparoscopic sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), or biliopancreatic diversion with duodenal switch (BPD/DS) with a minimum of 3 and up to 5 years of follow-up. The average daily dose for each type of insulin, measured in units, was calculated at annual intervals. Among 287 patients included, 201 (70%) underwent RYGB, 66 (23%) underwent SG, and 20 (7%) underwent BPD/DS. The average follow-up period was 4.6 ± 0.7 years. At 5 years follow-up, the mean total weight loss was the highest in the BPD/DS subgroup at 37.5% ± 11.6%. Insulin usage decreased significantly from complete dependency at baseline to 36.2% just 1 year postoperatively, and the use of noninsulin antidiabetic drugs decreased from 79.4% initially to 26.1%. These results were sustained throughout the study period. The subgroup analysis indicated that, 5 years after surgery, T2D remission was the highest after BPD/DS (73.7%) compared with RYGB (43.2%) and SG (23.3%) (P