Table 1.
Participant characteristics
| Variable | Obese white (n = 15) | Obese black (n = 15) | p value | p adjust FMI |
|---|---|---|---|---|
| Age (years) | 36±4 | 36±5 | 0.978 | |
| Body composition | ||||
| BMI (kg/m2) | 35.2±3.5 | 37.9±5.1 | 0.106 | |
| FFM (kg) | 52.4±7.4 | 49.7±6.7 | 0.297 | |
| Fat mass (kg) | 42.5±6.1 | 47.1±9.8 | 0.131 | |
| Body fat (%) | 44.8±3.6 | 48.4±3.4 | 0.008 | |
| FMI (kg/m2) | 15.4±2.2 | 18.1±3.6 | 0.017 | |
| Waist (cm) | 97.6±7.5 | 101.8±10.3 | 0.207 | |
| VAT (cm2) | 170±40 | 179±45 | 0.590 | 0.646 |
| SAT (cm2) | 534±89 | 596±101 | 0.085 | 0.903 |
| Circulating proteins | ||||
| Adiponectin (mg/l) | 4.4 (3.2–5.9) | 2.7 (2.0–3.8) | 0.025 | 0.022 |
| hs-CRP (ng/ml) | 4.4±2.2 | 5.2±2.8 | 0.425 | 0.983 |
| Ectopic fat | ||||
| Liver fat (%) | 3.6 (1.2–9.5) | 1.5 (1.1–2.1) | 0.077 | 0.065 |
| TA IMCL | 148 (90–274) | 119 (42–143) | 0.070 | 0.206 |
| Sol IMCL | 711 (507–1080) | 925 (506–1600) | 0.485 | 0.792 |
| TA fat content (%) | 6.7 (5.5–9.1) | 9.4 (7.1–14.2) | 0.028 | 0.083 |
| Sol fat content (%) | 10.8 (9.7–14.7) | 15.5 (13.4–18.9) | 0.003 | 0.074 |
| Basal clamp | ||||
| Fasting glucose (mmol/l) | 5.1±0.2 | 5.1±0.4 | 0.591 | 0.903 |
| Fasting insulin (pmol/l) | 64.4±5.4 | 90.7±39.1 | 0.028 | 0.188 |
| EGP (mg min–1 [kg FFM]–1) | 2.6 (2.0–3.8) | 2.7 (1.8–2.9) | 0.335 | 0.497 |
| Fasting RER | 0.73±0.04 | 0.77±0.07 | 0.076 | 0.084 |
| Fasting RMR (kJ [kg FFM]–1 day–1) | 134 (128–145) | 132 (126–152) | 0.702 | 0.767 |
| Low-dose clamp | ||||
| Glucose-low (mmol/l) | 4.6±0.3 | 4.6±0.3 | 0.671 | 0.716 |
| Insulin-low (pmol/l) | 134.1±42.6 | 158.4±35.2 | 0.100 | 0.237 |
| EGP-low (mg min–1 [kg FFM]–1) | 1.9 (1.6–2.7) | 0.8 (0–1.8) | 0.006 | 0.002 |
| Suppression of EGP (%) | 17 (5–51) | 56 (29–100) | 0.006 | 0.002 |
| M-low (mg min–1 [kg FFM]–1) | 0.75 (0.39–1.98) | 1.19 (0.33–3.73) | 0.757 | 0.187 |
| M/I-low (mg min–1 [kg FFM]–1 mmol/l–1) | 0.31 (0.15–0.80) | 0.39 (0.09–0.91) | 0.871 | 0.320 |
| Rd-low (mg min–1 [kg FFM]–1) | 3.0(2.4–4.1) | 2.5 (2.0–3.7) | 0.178 | 0.418 |
| RER-low | 0.75±0.06 | 0.77±0.06 | 0.317 | 0.218 |
| RMR-low (kJ [kg FFM]–1 day–1) | 136 (129–142) | 137 (129–145) | 0.791 | 0.712 |
| High-dose clamp | ||||
| Glucose-high (mmol/l) | 4.4±0.4 | 4.6±0.3 | 0.300 | 0.376 |
| Insulin-high (pmol/l) | 513.0±88.5 | 589.0±133.4 | 0.077 | 0.149 |
| M-high (mg min–1 [kg FFM]–1) | 9.3 (5.7–12.2) | 8.5 (4.8–12.2) | 0.962 | 0.631 |
| M/I-high (mg min–1 [kg FFM]–1 mmol/l–1) | 0.82 (0.70–1.36) | 0.76 (0.58–0.93) | 0.462 | 0.898 |
| RER-high | 0.83±0.06 | 0.85±0.08 | 0.573 | 0.457 |
| RMR-high (kJ [kg FFM]–1 day–1) | 139 (133–153) | 137 (130–156) | 0.964 | 0.731 |
For non-normally distributed data, values are median (IQR), with p values for log10-transformed data. For normally distributed data, values are means±SD
EGP, calculated as the rate of appearance of glucose minus the glucose infusion rate; High-dose clamp, high-dose (40 mU m–2 min–1) insulin infusion; Low-dose clamp, low-dose (10 mU/m–2 min–1) insulin infusion; M, glucose infusion rate, which reflects whole-body insulin sensitivity; RMR, resting metabolic rate; Sol, soleus; Suppression of EGP, calculated as the % change in EGP between baseline and the low-dose insulin infusion