Introduction: Hypoglycemia is a known adverse event following gastric bypass. The incidence of hypoglycemia after laparoscopic sleeve gastrectomy (LSG) is still under investigation. The aim of our study was to verify the presence of oral glucose tolerance test (OGTT)-related hypoglycemia after LSG and to identify any baseline predictors of its occurrence.
Methods: We analyzed 197 consecutive non-diabetic morbid obese patients that underwent LSG. All patients were studied before and 12 months after LSG. Evaluation included anthropometric parameters, 3-h OGTT for blood glucose (BG), insulin and c-peptide, lipid profile, interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), highly sensitive C-reactive protein (hsCRP), and leptin. Hypoglycemia was defined as BG ≤ 2.7 mmol/l.
Results: After surgery, 180 patients completed the OGTT. Eleven patients did not complete the test for gastric intolerance, and in six patients, the test was stopped earlier for the onset of severe symptomatic hypoglycemia. Of the patients, 61/186 (32.8%) had at least one OGTT-related hypoglycemia. The highest frequency of hypoglycemic events occurred 150' after glucose load (20.2%). At baseline, patients with hypoglycemic events after surgery (Hypo) were younger (40 ± 11 vs 46 ± 10 years; p < 0.001), less obese (BMI 46 ± 5.7 vs 48.4 ± 7.9 kg/m2; p < 0.05), and had a worse lipid profile as compared to patients without hypoglycemic events (N-Hypo). Moreover, after LSG, Hypo patients compared with N-Hypo presented a higher weight loss (%EBMIL 80 ± 20 vs 62 ± 21%; p < 0.001). Low age, low fasting glucose, and high triglyceride levels before LSG were independent predictors of hypoglycemia development after surgery (r 2 = 0.131).
Conclusion: These findings confirm the high incidence of post-prandial hypoglycemia 1 year after LSG. Hypoglycemia is more frequent in younger patients with lower fasting glucose and higher triglyceride levels before surgery.
Keywords: Bariatric surgery; Hypoglycemia; Laparoscopic sleeve gastrectomy.