The Effects of Laparoscopic Sleeve Gastrectomy (LSG) on Obesity-Related Type 2 Diabetes Mellitus: a Prospective Observational Study from a Single Center

Purpose The objective of the study is to evaluate the effects of laparoscopic sleeve gastrectomy (LSG) on mid- to long-term regulation of blood glucose in patients with obesity and type 2 diabetes mellitus (T2DM) Materials and Methods In this prospective and observational single-center study, a total of 234 patients with obesity and a diagnosis of T2DM who underwent LSG between 2015 and 2020 were evaluated. The demographics and laboratory data, consisting of body mass index (BMI), glycosylated hemoglobin (HbA1c%), and fasting plasma glucose (FPG) and total weight loss (TWL%), were compared preoperative and postoperative at 12 th and 18 th months and annual follow-up for seven consecutive years. Results The mean age of 234 patients (female( n )/male( n ):191/43) included in the study was 44.69±9.72 years, while the preoperative mean BMI, FPG, and HbA1c values were 47.9±6.82, 132.09±42.84 mg/dl, and 7.02±1.35% respectively. The mean rate of weight loss (TWL%), which was 34.7 in the 18 months, decreased to 23.15 in the 7 th year. While the HbA1c % value was 7.02±1.35 in the preoperative, it was found 5.71 ± 0.75 ( p <0.001) and 6.30 ± 1.77 ( p <0.05) at the 18 th month and 7 th year after the operation, respectively. While the DM remission rate was 71.1% at the postoperative 18 th month, it was 45.4% at the 7 th year, despite the patients regaining weight in the follow-ups. Conclusions Our study revealed that LSG resulted in high remission rates that continued for 7 years after the surgery, although sustained improvement or remission of diabetes despite some weight regain after the first 18 months. Graphical Abstract