Table 2.
Mean glucose, insulin, and C peptide levels, AUC for glucose and insulin during the OGTT and Iso IVGT, before and after weight loss by either diet (n = 10) or GBP (n = 9)
| Before GBP | After GBP | Before diet | After diet | |||||
|---|---|---|---|---|---|---|---|---|
| Oral | IV | Oral | IV | Oral | IV | Oral | IV | |
| GAUC (mmol/liter·min) | 11.2 ± 1.8 | 11.4 ± 1.8 | 8.5 ± 1.2 | 9.8 ± 1.2a | 10.3 ± 1.5 | 10.1 ± 1.6 | 9.1 ± 2.1 | 8.9 ± 2.3 |
| Glucose (mmol/liter) | 10.7 ± 1.9 | 10.9 ± 1.8 | 8.5 ± 1.0 | 9.4 ± 0.9 | 9.8 ± 1.2 | 9.6 ± 1.3 | 8.4 ± 1.8 | 8.3 ± 1.9 |
| IAUC (pmol/liter·min) | 349 ± 188 | 296 ± 154 | 340 ± 145 | 183 ± 75a | 363 ± 237 | 250 ± 131 | 350 ± 268 | 220 ± 165 |
| Insulin (pmol/liter) | 315 ± 152 | 261 ± 127 | 347 ± 138 | 170 ± 62a | 330 ± 210 | 218 ± 113 | 302 ± 191 | 195 ± 130 |
| C peptide (pmol/liter) | 1.95 ± 0.7 | 1.97 ± 0.57 | 2.31 ± 0.54 | 1.58 ± 0.4a | 1.98 ± 0.92 | 1.62 ± 0.81 | 1.89 ± 1.05 | 1.55 ± 0.95 |
| Incretin effect (%) | 9.42 ± 27.46 | 44.84 ± 12.73b | 27.44 ± 14.909 | 34.59 ± 15.15 | ||||
Data are expressed as mean ± sd. The incretin effect was calculated by comparing the insulin response to oral and matched iv glucose load. GAUC, Glucose area under the curve 0−180; IAUC, insulin area under the curve 0−180.
a
Between oral and iv glucose challenges within each group (P < 0.05).
b
Between before and after weight loss by either GBP or diet (P = 0.002).