TABLE 1.
Participant characteristics by race1
| African Americans (n = 55) | Caucasian Americans (n = 58) | P 2 | |
|---|---|---|---|
| Participant demographics | |||
| Age, y | 30 ± 1 | 28 ± 8 | 0.20 |
| Gender, males/females | 25/30 | 30/28 | 0.51 |
| Metabolic measurements | |||
| SIClamp, 10−4.dL.kg−1.min−1/(μU/mL) | 3.0 ± 1.2 | 5.2 ± 2.4 | <0.001 |
| Fasting glucose, mg/dL | 91.1 ± 8.4 | 88.6 ± 9.2 | 0.13 |
| Fasting insulin,3 μU/mL | 9.6 ± 5.2 | 7.5 ± 4.5 | 0.03 |
| HOMA2-IR3 | 1.1 ± 0.6 | 0.8 ± 0.5 | 0.03 |
| Body weight and composition | |||
| Weight, kg | 85.9 ± 19.1 | 76.5 ± 15.0 | 0.005 |
| BMI, kg/m2 | 29.3 ± 5.9 | 25.8 ± 4.7 | 0.001 |
| DXA measurements | |||
| Total fat mass, kg | 28.8 ± 12.1 | 24.8 ± 10.5 | 0.06 |
| Total fat mass, % | 32.9 ± 9.5 | 31.7 ± 8.9 | 0.49 |
| Total lean mass, kg | 53.4 ± 11.7 | 48.9 ± 9.2 | 0.02 |
| Leg fat, kg | 10.9 ± 5.0 | 8.8 ± 3.8 | 0.01 |
| MRI measurements | |||
| Subcutaneous abdominal adipose tissue, 4 L | 3.7 ± 2.2 | 2.9 ± 1.7 | 0.03 |
| Intra-abdominal adipose tissue, 4 L | 0.6 ± 0.5 | 0.8 ± 0.8 | 0.18 |
| Liver fat, 5 % | 0.4 ± 5.9 | 1.9 ± 7.6 | 0.26 |
Data are unadjusted mean ± SD, unless otherwise stated.
Total analyzed n = 113 (African Americans: 55, Caucasian Americans: 58) for all data unless otherwise stated.
P value for differences between races by independent samples t-test (continuous variables) or chi-square test (categorical variables).
Total analyzed n = 111 (African Americans: 54, Caucasian Americans: 57) for insulin and HOMA2-IR data; 2 outliers (values >3 SD over the group mean due to elevated fasting insulin) were excluded from analyses.
Total analyzed n = 112 (African Americans: 55, Caucasian Americans: 57) for SAAT and IAAT data; no abdominal MRI images were available for 1 Caucasian American.
Total analyzed n = 112 (African Americans: 54, Caucasian Americans: 58) for liver fat; data from 1 African American was excluded due to severe artifact. HOMA2-IR, homeostasis model of assessment index 2-insulin resistance; IAAT, intra-abdominal adipose tissue; SAAT, subcutaneous abdominal adipose tissue; SIClamp, skeletal muscle insulin sensitivity assessed by the hyperinsulinemic-euglycemic clamp.