Table 1

Phenotypic and metabolic characteristics of obese adolescents with NGT, IFG, IGT, IFG/IGT, and type 2 diabetes

NGTIFGIGTIFG/IGTType 2 diabetesP value*
2413291130
Age (years)13.9 ± 1.914.9 ± 1.914.5 ± 2.014.3 ± 2.115.3 ± 1.7NS
Sex (male/female)9/157/66/235/613/17NS
Ethnicity
    African American1076616NS
    American white14623514
Tanner stage
    II–III61532NS
    IV–V181224828
BMI (kg/m2)36.2 ± 4.133.5 ± 6.937.3 ± 7.336.0 ± 6.536.8 ± 5.3NS
Waist circumference (cm)108.2 ± 14.6100.0 ± 14.9106.0 ± 14.9109.3 ± 13.1108.6 ± 13.6NS
Body fat (%)46.5 ± 5.541.3 ± 7.445.5 ± 5.144.7 ± 5.341.7 ± 6.3NS
Subcutaneous abdominal fat (cm2)551.4 ± 138.6452.1 ± 192.0563.4 ± 167.4511.3 ± 147.2542.1 ± 136.1NS
Visceral fat (cm2)72.4 (46.8–93.4)67.8 (46.8–91.0)82.0 (55.6–104.0)50.7 (40.6–92.6)78.3 (62.4–88.6)NS
A1C (%)5.3 ± 0.4a5.6 ± 0.4b5.4 ± 0.4c5.2 ± 0.5d6.6 ± 0.8a,b,c,d<0.001
Fasting glucose (mg/dl)92.0 (88.3–96.1)102.6 (100.17–104.75)92.15 (89.0–94.5)104.5 (101.8–108.7)118.4 (103.1–138.5)<0.001
Fasting insulin (μU/ml)37.4 (29.8–44.2)26.3 (21.7–56.6)39.1 (27.4–55.6)36.8 (28.4–56.1)40.4 (33.9–57.2)NS
Fasting glucose–to-insulin ratio2.5 (2.0–3.3)3.9 (1.9–4.8)2.2 (1.7–3.5)2.8 (2.0–3.8)3.1 (2.4–4.1)NS
Proinsulin-to-insulin ratio0.17 (0.10–0.2)0.14 (0.12–0.16)0.13 (0.09–0.15)0.18 (0.09–0.25)0.20 (0.09–0.35)0.002
Postabsorptive hepatic glucose production (mg/kg/min)1.9 (1.7–2.3)2.1 (2.0–2.7)2.1 (1.7–2.6)2.5 (1.9–2.9)2.4 (2.1–3.2)0.007
Postabsorptive hepatic insulin resistance (mg/kg/min · μU/ml)75.1 (53.3–106.6)83.7 (48.3–116.3)83.9 (58.6–130.9)98.2 (60.2–169.7)102.4 (71.4–180.1)0.05
Cholesterol (mg/dl)170.1 ± 36.6157.2 ± 36.9171.3 ± 35.9175.1 ± 39.8158.1 ± 29.4NS
HDL (mg/dl)39.1 (34.4–49.6)36.9 (30.6–45.3)38.0 (32.4–44.6)38.1 (33.5–45.6)38.7 (33.1–41.8)NS
LDL (mg/dl)104.0 ± 34.494.1 ± 30.7103.3 ± 32.5110.1 ± 32.094.0 ± 27.3NS
Triglycerides (mg/dl)110.0 (92.0–161.0)84.0 (75.5–157.5)108.0 (92.0–189.0)109.0 (102.5–142.8)108.0 (87.0–148.8)NS
Triglycerides-to-HDL ratio2.8 (1.8–3.8)2.0 (1.7–5.0)2.9 (2.1–5.3)3.0 (2.7–3.8)3.1 (2.2–4.4)NS
  • Data are means ± SD or medians (25th percentile–75th percentile). Body composition data was missing for 2 subjects with NGT, 2 with IGT, and 5 with type 2 diabetes who exceeded the weight limit of 250 pounds of the dual-energy X-ray absorptiometry machine.

  • *P value from ANOVA for continuous variables with means presented and Kruskal-Wallis test with medians presented.

  • P value from χ2 test for categorical variables. Superscript letters are significant post hoc analysis (Bonferroni correction, P < 0.05):

  • atype 2 diabetes vs. NGT;

  • btype 2 diabetes vs. IFG;

  • ctype 2 diabetes vs. IGT;

  • dtype 2 diabetes vs. IFG/IGT. NS, not significant.