Rapid gastric emptying rate in postbariatric hypoglycemia and effect of glucagon-like peptide-1 receptor agonist on postprandial hypoglycemia.

CONTEXT: Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) are effective obesity treatments, but can be complicated by postbariatric hypoglycemia (PBH). Why some but not other patients develop this complication is unknown. Differential rates of gastric emptying have not been previously evaluated as a modifiable risk factor for PBH. OBJECTIVE: This work aimed to determine if gastric emptying is faster in individuals who develop PBH following RYGB and whether glucagon-like peptide-1 receptor agonist (GLP-1RA) treatment slows gastric emptying and/or prevents hypoglycemia in patients with PBH. METHODS: A cross-sectional comparison of gastric emptying rate was conducted in patients with PBH vs SCs, followed by a crossover study evaluating the effect of GLP-1RA on gastric emptying and hypoglycemia during mixed-meal tolerance testing (MMTT) and continuous glucose monitoring (CGM). Outcomes included the following: primary: 1-hour residual volume during solid-meal scintigraphy and glucose nadir during MMTT, and secondary: time of glucose nadir, fasting, and peak glucose, and hypoglycemia on CGM. RESULTS: Gastric emptying was 3-fold faster in RYGB patients with PBH (n = 17) vs SCs (n = 10; P = .031). GLP-1RA treatment significantly slowed gastric emptying, increasing 1-hour residual volume by 3-fold (P = .038). GLP-1RA treatment did not change nadir glucose (51 ± 11 vs 51 ± 6 mg/dL; P = .95) or nadir time (116 ± 36 vs 112 ± 22 minutes; P = .71); fasting glucose was significantly lower (75 ± 7 vs 79 ± 5; P = .031) and peak glucose significantly higher (176 ± 52 vs 158 ± 52; P = .004). CGM monitoring showed no reduction in hypoglycemia. CONCLUSION: Following RYGB, individuals with PBH exhibit faster gastric emptying than unaffected SCs. GLP-1RA therapy effectively slows gastric emptying in RYGB and SG but does not prevent hypoglycemia. This may be due to known effects of GLP-1RA on glucose lowering.