Diabetes remission is frequent after biliopancreatic diversion (BPD) in morbidly obese patients with type 2 diabetes (T2D). Data, mechanisms, and clinical indications in nonobese T2D patients are scanty.Objective:
The objective of the study was to assess remission and investigate insulin sensitivity and β-cell function after BPD in nonobese patients with long-standing T2D.Design, Setting, and Patients:
This was a clinical research study comparing 15 T2D patients (aged 55 ± 1 years, duration of 16 ± 2 years, body mass index of 28.3 ± 0.6 kg/m2, glycosylated hemoglobin 8.6% ± 1.3%) with 15 gender-, age-, and body mass index-matched nondiabetic controls. Before surgery and 2 months and 1 year later, a 3-hour oral glucose tolerance test, a 5-hour mixed-meal test, and a 3-hour euglycemic clamp were performed.Intervention:
The intervention included a BPD (distal gastrectomy, proximal ileum anastomosed to remaining stomach, biliopancreatic limb anastomosed to ileum 50 cm from the ileocecal valve).Results:
Glycemia improved in all patients, but remission (glycosylated hemoglobin < 6.5% and normal oral glucose tolerance test) occurred in 6 of 15 patients. Insulin resistance (19.8 ± 0.8 μmol · min−1 · kgffm−1, P < .001 vs 40.9 ± 5.3 of controls) resolved already at 2 months (34.2 ± 2.8) and was sustained at 1 year (34.7 ± 1.6), although insulin-mediated suppression of endogenous glucose production remained impaired. In contrast, β-cell glucose sensitivity (19  pmol·min−1 · m−2·mM−1 vs 96  of controls, P < .0001) rose (P = .02) only to 31  at 1 year and was lower in nonremitters (16 ) than remitters (46 ).Conclusions:
In nonobese patients with long-standing T2D, BPD improves metabolic control but induces remission in only approximately 40% of patients. Peripheral insulin sensitivity is restored early after surgery and similarly in remitters and nonremitters, indicating a weight-independent effect of the operation. The initial extent of β-cell incompetence is the main predictor of the metabolic outcome.