Postprandial
glucose is reduced in malnourished patients with
anorexia nervosa (AN), but the mechanisms and duration for this remain unclear. We examined
blood glucose, gastric emptying, and glucoregulatory
hormone changes in malnourished patients with AN and during 2 wk of acute refeeding compared with healthy controls (HCs). Twenty-two female adolescents with AN and 17 age-matched female HCs were assessed after a 4-h fast. Patients were commenced on a refeeding protocol of 2,400 kcal/day. Gastric emptying (13C-
octanoate breath test),
glucose absorption (3-O-methylglucose),
blood glucose, plasma
glucagon-like peptide-1 (GLP-1),
glucose-dependent insulinotropic
polypeptide (GIP),
insulin,
C-peptide, and
glucagon responses to a mixed-nutrient test meal were measured on admission and 1 and 2 wk after refeeding. HCs were assessed once. On admission, patients had slower gastric emptying, lower postprandial
glucose and
insulin, and higher
glucagon and
GLP-1 than HCs ( P < 0.05). In patients with AN, the rise in
glucose (0-30 min) correlated with gastric emptying ( P < 0.05). With refeeding, postprandial
glucose and
3-O-methylglucose were higher, gastric emptying faster, and baseline
insulin and
C-peptide less ( P < 0.05), compared with admission. After 2 wk of refeeding, postprandial
glucose remained lower, and
glucagon and
GLP-1 higher, in patients with AN than HCs ( P < 0.05) without differences in gastric emptying, baseline
glucagon, or postprandial
insulin. Delayed gastric emptying may underlie reduced postprandial
glucose in starved patients with AN; however, postprandial
glucose and glucoregulatory
hormone changes persist after 2 wk of refeeding despite improved gastric emptying. Future research should explore whether reduced postprandial
glucose in AN is related to medical risk by examining associated symptoms alongside continuous
glucose monitoring during refeeding.