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 beta-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 = .002) and trended similarly in the LSG group (P = .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) . m(-2), P = .001) and LSG groups (380 +/- 48 vs 339 +/- 60 mL/min(-1) . m(-2), P = .05) and improved to a similar extent in all groups after surgery. Before surgery, beta-cell glucose sensitivity was higher in PPHG than No-PPHG in both RYGB (118 +/- 67 vs 65 +/- 24 pmol/min(-1) . m(2) . mM(-1)) and LSG patients (114 +/- 32 vs 86 +/- 33) (both P = .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 beta-cell glucose sensitivity are significant predictors of PPHG after both RYGB and LSG.