Analysis of Changes in Glucose and Lipid Metabolism in Patients with Clinically Severe Obesity and Type 2 Diabetes Mellitus Undergoing Laparoscopic Sleeve Gastrectomy—Prospective Observational Study

We still lack studies providing analysis of changes in glucose and lipid metabolism after laparoscopic sleeve gastrectomy (LSG) in patients with type 2 diabetes mellitus (DM2). We aimed to investigate postoperative changes in glucose and lipid metabolism after LSG in patients with DM2.

Prospective, observational study included patients with BMI ≥ 35 kg/m² and ≤ 50 kg/m², DM2 < 10 years of duration, who were qualified for LSG. Perioperative 14-day continuous glucose monitoring (CGM) began after preoperative clinical assessment and OGTT, then reassessment 1 and 12 months after LSG. Thirty-three patients in mean age of 45 ± 10 years were included in study (23 females).

EBMIL before LSG was 17 ± 11.7%, after 1 month—36.3 ± 12.8%, while after 12 months—66.1 ± 21.7%. Fifty-two percent of the patients had DM2 remission after 12 months. None required then insulin therapy. 16/33 patients initially on oral antidiabetics still required them after 12 months. Significant decrease in HbA_1C was observed: 5.96 ± 0.73%; 5.71 ± 0.80; 5.54 ± 0.52%. Same with HOMA-IR: 5.34 ± 2.84; 4.62 ± 3.78; 3.20 ± 1.99. In OGTT, lower increase in blood glucose with lesser insulin concentrations needed to recover glucose homeostasis was observed during follow-ups. Overtime perioperative average glucose concentration in CGM of 5.03 ± 1.09 mmol/L significantly differed after 12 months, 4.60 ± 0.53 (p = 0.042). Significantly higher percentage of glucose concentrations above targeted compartment (3.9–6.7 mmol/L) was observed in perioperative period (7% ± 4%), than in follow-up (4 ± 6% and 2 ± 1%). HDL significantly rose, while triglyceride levels significantly decreased.

Significant improvement in glucose and lipid metabolism was observed 12 months after LSG and changes began 1 month after procedure.