Risk factors for spontaneously self-reported postprandial hypoglycemia after bariatric surgery

Context: Postprandial hypoglycemia (PPHG) is a recognized complication of Roux-en-Y gastric bypass (RYGB) surgery. Data on PPHG after laparoscopic sleeve gastrectomy (LSG) are scant. Objective: The objective of the study was to identify preoperative predictors of PPHG in subjects spontaneously self-reporting PPHG after RYGB or LSG. Patients, Setting, and Intervention: Nondiabetic patients spontaneously self-reporting symptoms/signs of PPHG (PPHG group, 21 RYGB and 11 LSG) were compared in a case-control design with subjects who never experienced spontaneous or oral glucose tolerance test (OGTT)-induced hypoglycemia over 24 months after surgery (No-PPHG group, 13 RYGB and 40 LSG). Paired pre-and postoperative 3-hour OGTTs were analyzed in all participants. Main Outcome Measures: Insulin sensitivity was assessed by the oral glucose insulin sensitivity index and β-cell function by mathematical modeling of the C-peptide response to glucose. Results: Before surgery, the body mass index was lower in PPHG than No-PPHG patients in the RYGB (P β.002) and trended similarly in the LSG group (P β.08). Fasting glycemia and the glucose-OGTT nadir were lower in the PPHG than the No-PPHG subjects in both surgery groups. Before surgery, insulin sensitivity was higher in PPHG than No-PPHG in the RYGB (393 ± 55 vs 325 ± 44 mL/min-1 β m-2, P β.001) and LSG groups (380 ± 48 vs 339 ± 60 mL/min-1 β m-2, P β.05) and improved to a similar extent in all groups after surgery. Before surgery, β-cell glucose sensitivity was higher in PPHG than No-PPHG in both RYGB (118 ± 67 vs 65 ± 24 pmol/min-1 β m2 β mM-1) and LSG patients (114 ± 32 vs 86 ± 33) (both P β.02) and improved in all subjects after surgery. Conclusions: In subjects self-reporting PPHG after surgery, lower presurgery plasma glucose concentrations, higher insulin sensitivity, and better β-cell glucose sensitivity are significant predictors of PPHG after both RYGB and LSG