title: Restoration of euglycemia and normal acute insulin response to glucose in obese subjects with type 2 diabetes following bariatric surgery.
abstract: Insulin resistance and loss of glucose-stimulated acute insulin response (AIR) are the two major and earliest defects in the course of type 2 diabetes. We investigated whether weight loss after bariatric surgery in patients with morbid obesity and type 2 diabetes could restore euglycemia and normal AIR to an intravenous glucose tolerance test (IVGTT). We studied 25 morbidly obese patients-12 with type 2 diabetes, 5 with impaired glucose tolerance, and 8 with normal glucose tolerance (NGT)-before and after a biliopancreatic diversion (BPD) with Roux-en-Y gastric bypass (RYGBP). Twelve individuals with normal BMI served as control subjects. Twelve months after surgery, in the diabetes group, BMI decreased from 53.2 +/- 2.0 to 29.2 +/- 1.7 kg/m(2), fasting glucose decreased from 9.5 +/- 0.83 to 4.5 +/- 0.13 mmol/l, and fasting insulin decreased from 168.4 +/- 25.9 to 37.7 +/- 4.4 pmol/l (mean +/- SE; P < 0.001). AIR, the mean of insulin concentration at 2, 3, and 5 min over basal in the IVGTT, increased by 770 and 935% at 3 and 12 months after surgery, respectively (from 24.0 +/- 22.7 to 209 +/- 43.4 and 248 +/- 33.1 pmol/l, respectively; P < 0,001). Conversely, in the NGT group, the AIR decreased by 40.5% (from 660 +/- 60 to 393 +/- 93 pmol/l; P = 0.027) 12 months after surgery. BPD with RYGBP performed in morbidly obese patients with type 2 diabetes leads to significant weight loss, euglycemia, and normal insulin sensitivity; but most importantly, it restores a normal beta-cell AIR to glucose and a normal relationship of AIR to insulin sensitivity. This is the first study to demonstrate that the lost glucose-induced AIR in patients with type 2 diabetes of mild or moderate severity is a reversible abnormality.
authors.affiliation: Department of Internal Medicine, Division of Endocrinology, University Hospital, University of Patras Medical School, Rion, Patras 26500, Greece.
authors.forename: Eftihia V
authors.initials: EV
authors.lastname: Polyzogopoulou
authors.forename: Fotios
authors.initials: F
authors.lastname: Kalfarentzos
authors.forename: Apostolos G
authors.initials: AG
authors.lastname: Vagenakis
authors.forename: Theodore K
authors.initials: TK
authors.lastname: Alexandrides
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism*; D001823:Body Composition; D015992:Body Mass Index; D001835:Body Weight; D003920:Diabetes Mellitus / Q000097:blood / Q000601:surgery*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000601:surgery; D005215:Fasting; D005260:Female; D005500:Follow-Up Studies; D015390:Gastric Bypass; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood* / Q000494:pharmacology; D008297:Male; D009765:Obesity; D009767:Obesity, Morbid / Q000097:blood* / Q000601:surgery*; D012016:Reference Values; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D007328:Insulin