Could Glycated Hemoglobin be Leakage Predictor in Sleeve Gastrectomy? A Retrospective Observational Study on 4233 Patients

Purpose Diabetes increases the risks related to surgery. At the same time, bariatric surgery improves diabetes. Glycated hemoglobin (A1C) is an index of diabetes severity. The purpose of this study is to evaluate A1C as a possible predictor of postoperative complications after Sleeve Gastrectomy (SG), focusing on leakage. Materials and Methods Monocentric retrospective study considering all consecutive patients with obesity, with or without diabetes, who underwent bariatric surgical procedures, from January 2018 to December 2021. All patients had preoperative A1C values. Results 4233 patients were considered. 522 patients (12.33%) were diabetics (A1C ≥ 6.5%). Of these, 260 patients (6.14%) had A1C ≥ 7% and 59 (1.39%) A1C ≥ 8%. 1718 patients (40.58%) were in a pre-diabetic range (A1C 5.7%—6.5%). Higher A1C values were associated with older age, male gender, higher BMI and increased rate of comorbidities. A longer operative time was observed for patients with A1C ≥ 7%, p = 0.027 (53 ± 20 vs 51 ± 18 min). The frequency of leakage was significantly higher when A1C ≥ 7% (3.8% vs 2.0%, p = 0.026). The frequency of leakage further increased when A1C ≥ 8% (5.1%), although this difference did not reach statistical significance. Conclusion Patients with obesity and A1C ≥ 7% need to be referred to a diabetologist to treat diabetes before surgery and consequently decrease the risk of leakage. Graphical Abstract