Acarbose improves hypoglycaemia following gastric bypass surgery without increasing glucagon-like peptide 1 levels.

BACKGROUND: Postprandial hypoglycaemia is a severe complication of Roux-en-Y gastric bypass (RYGBP). Acarbose, an α-glucosidase inhibitor (AGI), is employed in its treatment. Several studies have shown that AGIs increase the postprandial levels of glucagon-like peptide 1 (GLP-1). However, an excessive level of GLP-1 is one of the factors involved in the physiopathology of this condition. We analysed the effect of acarbose oral administration in eight RYBGP patients with clinically significant hypoglycaemia or dumping syndrome. METHODS: Glucose, insulin and GLP-1 plasma levels in fasting and after ingestion of a standard meal (Ensure Plus®; 13 g protein, 50 g carbohydrate, 11 g fat) were measured. The test was repeated the following week with the oral administration of 100 mg of acarbose 15 min prior to the meal. RESULTS: Five patients developed asymptomatic hypoglycaemia during the test (glucose level <50 mg/dl) with inappropriately high insulin levels and exaggerated GLP-1 response. Acarbose ingestion avoided hypoglycaemia in all of the patients and increased the lowest plasma glucose level (46.4 ± 4.8 vs. 59.0 ± 2.6 mg/dl, p < 0.01). Acarbose ingestion decreased the area under the curve for serum insulin and GLP-1 levels at 15 min after the meal. CONCLUSIONS: Acarbose avoided postprandial hypoglycaemia following RYGBP by decreasing the hyperinsulinemic response. This was associated with a decrease in early GLP-1 secretion, in contrast to that observed in non-surgical subjects. This finding could be explained by the reduction of glucose load in the jejunum produced by the α-glucosidase inhibition, which is the main stimulus for GLP-1 secretion.

Near-optimal glycemic control in Chilean women with pregestational type-2 diabetes: persistent macrosomia relates to maternal pre-pregnancy overweight.

UNLABELLED: After a 10-year program intending to improve glycemic control in diabetic pregnancies, we evaluated whether factors underlying macrosomia are similar for type-1 and -2 pregestational diabetic women. PATIENTS AND METHODS: Twenty-three pregnancies in type-1 diabetics (PDM1, age 28.3+/-1.1 years) and 51 pregnancies in type-2 diabetics (PDM2, age 32.8+/-0.6 years) were followed and treated with intensified insulin therapy. Several factors potentially influencing macrosomia were evaluated. STATISTICS: chi-square, Fisher's exact, Student's "t" and Mann-Whitney "U" tests, and ROC analysis. RESULTS: In PDM1 and PDM2, respectively, large-for-gestational-age (LGA) frequencies were 26.08% and 37.25% (NS), antepartum HbA1c values were 6.5+/-0.32 and 6.1+/-0.16 (NS), and pre-pregnancy body mass indexes (BMI) were 23.03+/-0.66 and 30.01+/-0.89 (p<0.0001). In PDM1 the main predictor of LGA was an antepartum HbA1c> or =6.8% (p=0.046), whereas in PDM2 pregestational BMI> or =24 the variable associated (p=0.032) with LGA newborns. CONCLUSIONS: PDM1 and PDM2 differ in the underlying factors related to macrosomia. Whereas in PDM1 the antepartum HbA1c emerged as the most significant variable, suggesting that glycemic control largely determines macrosomia, in PDM2 with near-optimal glycemic control, macrosomia related to pregestational BMI.