Effects of Roux-en-Y Gastric Bypass or Diabetes Support and Education on Insulin Sensitivity and Insulin Secretion in Morbidly Obese Patients With Type 2 Diabetes

Abstract

Objective The long-term changes in insulin sensitivity and β-cell function in morbidly obese patients with type 2 diabetes (T2DM) who undergo RYGB surgery or standard medical care remain unclear. We prospectively studied longitudinal changes of glucostatic parameters in morbidly obese patients with T2DM undergoing RYGB surgery or Diabetes Support and Education (DSE). Research Methods and Design 61 morbidly obese subjects (41.7±0.6 kg/m2) with T2DM were assigned to RYGB surgery (n=30) or DSE (n=31). They were matched for sex, age and body weight. Insulin sensitivity index (Si) and acute insulin response (AIR) were derived from frequently sampled intravenous glucose tolerance test. Body composition was measured using dual-emission absorptiometry X-ray. General linear model with repeated measures were used to examine the longitudinal changes (baseline, 6-month, 12-month) in these parameters. Results At 12-month follow-up, significant improvement in obesity measures, body composition, glucose homeostasis, Si and AIR were observed following RYGB surgery and weight loss. These outcomes were not influenced by pre-operative insulin use. Although there were no significant changes in the body composition amongst DSE subjects, they experienced a decline in the Si and AIR, along with an increase in fasting glucose and HbA1c. The between-group differences in Si and AIR at 12-month follow-up were completely attenuated with adjustment to changes in body weight. Conclusions The long-term effects of RYGB surgery on glucostatic parameters are partly dependent on weight loss. In morbidly obese diabetic patients who were offered DSE, a progressive decline in the glucose homeostasis and glucostatic parameters is observed despite absence of weight gain. (NCT00787670)

Long-term outcomes after Roux-en-Y gastric bypass: 10- to 13-year data

“…Hypertension, hyperlipidemia, and diabetes mellitus have been studied extensively in the post-bariatric surgery patient with promising outcomes, although usually limited to short-or mid-term results [2,[4][5][20][21][22][23][24][25]. A meta-analysis by Heneghan et al revealed absolute improvement in SBP from 139 mm Hg to 124 mm Hg, LDL from 118 mg/dL to 94 mg/dL, and HbA 1c from 7.5% to 6.0% at 34 months average follow-up [21].…”

Gastric bypass significantly improves quality of life in morbidly obese patients with type 2 diabetes

“…Patients in the two groups were matched by age (RYGB: 48.8 ± 7.5 years versus DSE: 47.4 ± 8.4 years, P=0.463), gender (RYGB: 66.7 % female versus DSE: 67.7% female, P=0.929), weight (RYGB: 120.1 ± 17.0 kg versus DSE: 114.3 ± 17.1 kg, P=0.186), waist-to-hip ratio (RYGB: 0.98 ± 0.08 versus DSE: 0.97 ± 0.09, P=0.580), IR (RYGB: 8.1 ± 12.2 versus DSE: 6.1 ± 6.3, P=0.444), Si (RYGB: 1.5 ± 1.2 mU/L -1 *min -1 versus DSE: 1.4 ± 1.2 mU/L -1 *min -1 , P=0.753), FPG (RYGB: 155.6 ± 47.2 mg/dL versus DSE: 149.1 ± 50.6 mg/dL, P=0.607), HbA 1 c (RYGB: 7.53 ± 1.3 % (59 ± 14.2 mmol/mol) versus DSE: 7.51 ± 1.3 % (59 ± 14.2 mmol/mol), P=0.943), Insulin (RYGB: 21.9 ± 29.4 μU/mL versus DSE: 16.9 ± 14.6 μU/mL, P=0.401), oral anti-diabetic medications (RYGB: 27% versus DSE: 29%, P=0.837) and insulin therapy (RYGB: 73% versus DSE: 71%, P=0.837). These data have been previously published [20]. …”

“…Based on patient selection and/or insurance approval for RYGB, 30 patients underwent laparoscopic RYGB and 31 patients received 1-year of DSE, as previously described [20]. This program was run on a per-year basis and consisted of three group educational and support sessions during the year.…”

Improved insulin sensitivity after gastric bypass correlates with decreased total body fat, but not with changes in free fatty acids

“…We studied 30 morbidly obese (body mass index [BMI] > 35 kg/m 2 ) patients with a diagnosis of T2DM preoperatively and 12 months after LRYGB as previously described 23 . Inclusion criteria included clinical diagnosis of T2DM diabetes mellitus according to the American Diabetes Association criteria 24 with HbA1c • 10.0%, BMI • 35 kg/m 2 in accord with the 1991 NIH obesity surgery consensus conference criteria and stable weight for the previous 3 months 25 , and age between 18 and 60 years.…”