Table 1.
Changes in glucose metabolism following the period of caloric restriction alone (Diet only Period) versus identical caloric restriction along with gastric bypass surgery (Diet and RYGB Period)
| Measurement | Diet only Period | Diet and RYGB Period | Between periods | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | End | Change | P | Baseline | End | Change | P | P | |
| Fasting Glucose (mmol/L) |
9.22 (7.23 to 11.21) | 7.25 (5.65 to 8.84) | −1.97 (−3.82 to −0.12) | 0.04 | 8.53 (6.55 to 10.51) | 7.53 (5.95 to 9.12) | −0.99 (−2.83 to 0.85) | 0.25 | 0.19 |
| Glucose AUC (mmol L−1min) |
4,221.3 (3,232.4 to 5,210.2) | 3,566.6 (2,811.0 to 4,322.2) | −654.7 (−1,279.2 to −30.2) | 0.04 | 3,942.8 (3,013.3 to 4,872.3) | 3,399.4 (2,689.2 to 4,099.7) | −543.3 (−1,130.3 to 43.7) | 0.07 | 0.60 |
| Fasting C-peptide (ng/mL) | 2.72 (1.91 to 3.54) | 3.26 (1.90 to 4.61) | 0.54 (−0.84 to 1.91) | 0.40 | 2.83 (1.94 to 3.72) | 2.63 (1.15 to 4.11) | −0.20 (−1.71 to 1.30) | 0.77 | 0.10 |
| C-peptide AUC (ng mL−1min) |
1,701.7 (1,102.0 to 2,301.4) | 2,061.7 (1,416.0 to 2,707.3) | 360.0 (−286.9 to 1,006.8) | 0.24 | 1,613.3 (1,122.5 to 2,103.7) | 1,556.0 (1,027.8 to 2,084.2) | −57.1 (−586.3 to 472.1) | 0.81 | 0.06 |
| Ratio (C-peptide AUC/Glucose AUC) | 0.02 (0.01 to 0.04) | 0.04 (0.03 to 0.05) | 0.02 (0.004 to 0.03) | 0.01 | 0.03 (0.02 to 0.03) | 0.03 (0.02 to 0.04) | 0.004 (−0.005 to 0.01) | 0.35 | 0.02 |
| Ratio (Δ0-30 min C-peptide/Δ0-30 Glucose) | 0.06 (0.03 to 0.09) | 0.07 (0.03 to 0.11) | 0.01 (−0.04 to 0.06) | 0.74 | 0.06 (0.03 to 0.09) | 0.05 (0.02 to 0.08) | −0.01 (−0.05 to 0.04) | 0.76 | 0.66 |
| Fasting Insulin (pmol/L) |
70.76 (44.95 to 96.58) | 51.94 (38.17 to 65.70) | −18.83 (−42.63 to 4.98) | 0.11 | 64.63 (37.61 to 91.65) | 34.65 (20.24 to 49.06) | −29.98 (−54.89 to −5.06) | 0.02 | 0.41 |
| Insulin AUC (pmol L−1min) |
52,260 (33,946 to 70,575) | 54,786 (39,789 to 69,783) | 2,527 (−17,141 to 22,195) | 0.78 | 48,116 (32,435 to 63,796) | 29,581 (16,740 to 42,421) | −18,535 (−35,375 to −1,695) | 0.03 | 0.51 |
| Fasting Insulin Secretion (pmol min−1m−2) |
102.3 (72.0 to 132.6) | 120.7 (67.8 to 173.6) | 18.4 (−34.7 to 71.5) | 0.45 | 105.4 (73.0 to 137.8) | 99.1 (42.5 to 155.6) | −6.3 (−63.01 to 50.4) | 0.81 | 0.14 |
| ISR at 9 mmol/L (pmol min−1m−2) |
172.0 (48.4 to 295.6) | 287.9 (116.4 to 459.4) | 115.9 (−27.6 to 259.4) | 0.10 | 160.5 (80.8 to 240.2) | 183.6 (73.0 to 294.2) | 23.1 (−69.4 to 115.6) | 0.59 | 0.054 |
| Glucose Sensitivity (pmol min−1m−2mmol−1L) |
29.31 (6.22 to 52.40) | 53.63 (14.86 to 92.40) | 24.32 (−20.90 to 69.54) | 0.25 | 26.28 (10.64 to 41.93) | 32.65 (6.38 to 58.92) | 6.36 (−24.28 to 37.00) | 0.65 | 0.12 |
| Rate Sensitivity (pmol m−2mmol−1L)† |
711.3 (217.0 to 1,666.0) | 1,458.0 (881.6 to 1,880.6) | 526.5 (−523.3 to 1,402.5) | 0.15 | 1,213.7 (784.5 to 2,131.7) | 844.93 (249.5 to 1,860.3) | −199.7 (−1,539.8 to 733.3) | 0.34 | 0.07 |
| 3-h Potentiation Ratio (dimensionless) | 1.22 (0.90 to 1.53) | 1.19 (0.78 to 1.59) | −0.03 (−0.47 to 0.41) | 0.88 | 1.28 (0.96 to 1.60) | 1.28 (0.87 to 1.69) | −0.003 (−0.44 to 0.43) | 0.99 | 0.92 |
| Total ISR (nmol m−2) |
66.15 (42.06 to 90.24) | 81.37 (55.67 to 107.07) | 15.22 (−10.40 to 40.84) | 0.21 | 61.93 (42.17 to 81.69) | 60.87 (39.78 to 81.95) | −1.06 (−22.08 to 19.95) | 0.91 | 0.07 |
| Clinsb (L min−1m−2) |
1.91 (1.08 to 2.74) | 2.80 (1.12 to 4.47) | 0.89 (−0.54 to 2.31) | 0.19 | 2.03 (1.17 to 2.90) | 3.55 (1.81 to 5.29) | 1.52 (0.04 to 3.00) | 0.046 | 0.43 |
| Clins (L min−1m−2) |
1.77 (0.89 to 2.66) | 1.97 (1.12 to 2.82) | 0.2 (−0.59 to 0.98) | 0.59 | 1.68 (0.99 to 2.38) | 2.55 (1.88 to 3.22) | 0.87 (0.24 to 1.49) | 0.01 | 0.03 |
| Disposition Index | 0.14 (0.06 to 0.22) | 0.27 (0.07 to 0.46) | 0.13 (−0.02 to 0.28) | 0.09 | 0.13 (0.06 to 0.21) | 0.29 (0.11 to 0.48) | 0.16 (0.02 to 0.31) | 0.03 | 0.59 |
| 2-h OGIS (mL min−1m−2) |
251.1 (198.5 to 303.6) | 306.6 (260.6 to 352.5) | 55.5 (2.2 to 108.7) | 0.04 | 298.6 (201.3 to 395.9) | 309.0 (223.9 to 394.0) | 10.4 (−88.2 to 109.0) | 0.82 | 0.25 |
| HOMA2-IR | 1.73 (1.12 to 2.35) | 1.20 (0.82 to 1.58) | −0.53 (−1.06 to 0.004) | 0.051 | 1.47 (0.94 to 2.00) | 0.82 (0.49 to 1.15) | −0.65 (−1.11 to −0.19) | 0.01 | 0.64 |
| Matsuda Index | 4.60 (2.94 to 6.27) | 6.73 (4.20 to 9.27) | 2.13 (0.28 to 3.98) | 0.03 | 5.24 (2.36 to 8.11) | 9.16 (4.78 to 13.53) | 3.92 (0.73 to 7.11) | 0.02 | 0.29 |
| Stumvoll Index (μmol min−1kg−1) |
0.75 (−0.22 to 1.71) | 1.83 (0.84 to 2.83) | 1.08 (0.41 to 1.76) | 0.006 | 1.26 (0.02 to 2.49) | 2.65 (1.37 to 3.93) | 1.39 (0.52 to 2.26) | 0.006 | 0.27 |
Data represents Least Squares Means (95% CI). The significance of the change within each period under the Diet only Period and Diet and RYGB Period, respectively, whereas the significance of the change between periods is shown in the Between periods column.
AUC – area under the curve, ISR - Insulin secretion at 9.0 mmoL/L glucose from the dose-response, Glucose Sensitivity - mean slope of the dose-response in the observed glucose range, Rate Sensitivity – derivate component evaluating the dynamic dependence of insulin secretion on the rate of change of glucose concentration, 3-h Potentiation Ratio - ratio between the mean value in the intervals [160-180] and [0-20] min. Total ISR - integral of total insulin secretion, Clinsb - basal insulin clearance (basal insulin secretion/basal insulin), Clins - insulin clearance (insulin secretion AUC/insulin AUC), 2-h OGIS - oral glucose insulin sensitivity index (2-h equation), HOMA2-IR – homeostasis model of assessment of insulin resistance.
Rate Sensitivity was rank transformed prior to analysis; data reported as median and 95%CI.