Table 1

Baseline physical characteristics, demographic characteristics, and OGTT-based measures in drug-naïve youth vs. adults and in IGT vs. type 2 diabetes

Youth (n = 66) (1)Adults (n = 355) (2)Youth vs. adults, P value (1 vs. 2)IGT (n = 304) (3)Type 2 diabetes (n = 117) (4)IGT vs. type 2 diabetes, P value (3 vs. 4)
Demographic characteristics
 Age (years)14.2 ± 2.052.7 ± 9.4<0.00145.7 ± 16.949.0 ± 15.10.069
 Male, n (%)19 (28.8)172 (48.5)0.005140 (46.1)51 (43.6)0.730
 Race/ethnicity, n (%)<0.0010.197
  White19 (28.8)166 (46.8)140 (46.1)45 (38.5)
  Black14 (21.2)97 (27.3)83 (27.3)28 (23.9)
  Hispanic25 (37.9)68 (19.2)62 (20.4)31 (26.5)
  Other8 (12.1)24 (6.8)19 (6.2)13 (11.1)
 Weight (kg)98.9 ± 22.6100.8 ± 18.20.454101.1 ± 18.998.9 ± 19.10.281
 Height (cm)163.7 ± 9.0169.2 ± 9.7<0.001168.3 ± 9.8168.4 ± 9.80.934
 BMI (kg/m2)36.6 ± 6.035.1 ± 5.10.03535.6 ± 5.334.8 ± 5.20.148
 Triponderal index (kg/m3)22.4 ± 3.520.8 ± 3.3<0.00121.2 ± 3.420.7 ± 3.30.166
 Waist circumference (cm)109.0 ± 14.2110.3 ± 12.60.475110.9 ± 13.2108.3 ± 11.80.070
Glycemic characteristics
 HbA1c (mmol/mol)38.54 ± 6.1139.64 ± 4.350.08038.42 ± 4.1142.17 ± 4.99<0.001
 Diabetes at screening, n (%)0.147
  IGT 53 (80.3)251 (70.7)
  Diabetes13 (19.7)104 (29.3)
OGTT parameters
 Fasting glucose (mmol/L)5.93 ± 0.936.15 ± 0.650.0195.94 ± 0.566.56 ± 0.84<0.001
 Fasting C-peptide (nmol/L)1.64 ± 0.5871.24 ± 0.479<0.0011.29 ± 0.4791.34 ± 0.6060.392
 Fasting insulin (pmol/L)218.2 (70.4, 676.5)106.4 (35.6, 318.4)<0.001120.8 (36.8, 396.7)115.1 (32.1, 412.6)0.473
 Two-hour glucose (mmol/L)9.89 ± 2.4610.15 ± 2.370.4049.34 ± 1.7812.1 ± 2.59<0.001
 Two-hour C-peptide (nmol/L)5.8 ± 2.344.7 ± 1.55<0.0015.02 ± 1.764.57 ± 1.640.018
 Two-hour insulin (pmol/L)1,418.7 (358.8, 5,608.9)788.8 (231.7, 2,685.5)<0.001907.1 (237.1, 3,469.5)764.9 (225.3, 2,597.3)0.020
Incremental OGTT AUC (0–180 min)
 G-iAUC (mmol/L · min)595.9 ± 234.9613.6 ± 250.70.600538.7 ± 192.4794.1 ± 278.6<0.001
 CP-iAUC (nmol/L · min)528.7 (249.5, 1,120.1)424.4 (214.2, 840.7)<0.001460.4 (236.9, 894.8)387.8 (179.8, 836.7)<0.001
 I-iAUC (pmol/L · min)171,453 (49,351, 595,658)91,284 (28,568, 291,676)<0.001108,638 (32,184, 366,705)82,775 (23,038, 297,408)<0.001
Estimates of insulin sensitivity, insulin clearance, and β-cell function
 1/FI [× 10−3 1/(pmol/L)]5.45 ± 3.8810.94 ± 6.41<0.0019.85 ± 5.9610.67 ± 7.410.237
 Fasting C-peptide/insulin (× 10−2 nmol/pmol)0.71 (0.36, 1.37)1.09 (0.59, 2.03)<0.0011.00 (0.50, 2.01)1.07 (0.53, 2.16)0.075
 CPI (nmol/mmol)0.703 (0.226, 2.183)0.401 (0.136, 1.183)<0.0010.508 (0.171, 1.51)0.297 (0.111, 0.796)<0.001
 IGI (pmol/mmol)257.3 (54.5, 1,215.8)114.8 (28.0, 470.8)<0.001154.1 (34.1, 697.4)84.7 (23, 311.9)<0.001
 CP-iAUC/G-iAUC (nmol/mmol)0.972 (0.332, 2.846)0.762 (0.261, 2.218)0.0010.927 (0.368, 2.335)0.526 (0.184, 1.505)<0.001
 I-iAUC/G-iAUC (pmol/mmol)312.6 (72.7, 1,343.3)163.9 (40.9, 657.0)<0.001218.7 (58.7, 814.4)112.3 (26.8, 470.1)<0.001
  • Data are mean ± SD or geometric mean (95% CI). P values for nonnormally distributed data based on log-transformed values. “Other” for self-reported race/ethnicity includes, mixed, Asian, American Indian, and other.