TABLE 4

Surrogate indexes of insulin sensitivity and β-cell function across categories of glucose tolerance

nNGTIsolated IFGIsolated IGTIFG + IGTNewly diagnosed diabetesP
n2,1542,831213694467
β-Cell function
    HOMA-β (mU/l, mmol/l)6,35960.0 (44.2–87.3)56.4 (40.0–84.3)78.2 (51.0–128.7)81.7 (51.0–115.3)*71.5 (43.3–109.4)9 × 10−60
    Insulinogenic index (pmol/mmol)6,312100 (62–166)96 (58–158)75 (44–137)84 (51–133)54 (30–84)9 × 10−129
    InsAUC30/GluAUC30 (pmol/mmol)6,32524.1 (16.8–37.0)24.8 (16.8–37.0)24.9 (15.7–45.9)*26.2 (17.7–40.3)21.0 (12.4–31.8)1 × 10−65
    InsAUC120 (nmol/l · min)6,32126.1 (17.5–40.2)30.1 (20.7–45.4)40.6 (24.9–68.8)47.3 (30.6–70.1)41.2 (25.9–63.7)9 × 10−47
    ΔInsAUC120/ΔGluAUC120 (pmol/mmol)6,311143 (88–239)153 (94–246)*99 (59–159)114 (73–172)75 (43–124)2 × 10−149
    InsAUC120/GluAUC120 (pmol/mmol)6,32033.2 (23.2–50.3)34.4 (24.0–50.1)42.1 (25.5–67.8)*42.5 (28.4–64.2)*32.3 (20.0–50.8)2 × 10−39
    First-phase Stumvoll (pmol/l, mmol/l)6,325859 (640–1,185)818 (555–1,173)786 (560–1,342)*833 (546–1,283)612 (270–1,008)2 × 10−88
    Second-phase Stumvoll (pmol/l, mmol/l)6,325234 (187–310)232 (174–315)221 (172–357)*239 (175–348)198 (118–292)3 × 10−84
Insulin sensitivity/resistance
    Fasting serum insulin (pmol/l)6,36030.6 (22.2–45.0)41.4 (29.4–63.6)40.5 (27.0–69.0)64.2 (40.5–91.8)73.2 (43.8–116.4)3 × 10−122
    HOMA-IR (mU/l, mmol/l)6,3601.2 (0.9–1.7)1.8 (1.3–2.8)1.6 (1.0–2.7)2.9 (1.8–4.2)3.7 (2.2–6.7)6 × 10−266
    QUICKI (mU/l, mg/dl)6,3600.37 (0.35–0.39)0.35 (0.33–0.37)0.36 (0.33–0.38)0.33 (0.31–0.35)0.31 (0.29–0.34)8 × 10−255
    MCR Stumvoll (pmol/l, mmol/l)6,3608.1 (7.6–8.5)6.9 (6.0–7.4)7.9 (6.8–8.3)5.9 (4.7–6.8)4.4 (2.2–5.7)<1 × 10−255
    ISI Stumvoll (pmol/l, mmol/l)6,3530.11 (0.10–0.12)0.10 (0.09–0.11)0.07 (0.05–0.09)0.06 (0.04–0.08)0.04 (0.01–0.06)<1 × 10−255
    Matsuda ISI (mU/l, mg/dl)6,3208.2 (5.6–11.9)5.8 (3.8–8.2)5.0 (3.1–8.0)3.2 (2.2–5.0)2.7 (1.7–4.4)1 × 10−255
Disposition index
    DI306,320195 (157–245)139 (112–173)123 (100–152)88 (73–107)55 (44–73)<1 × 10−255
    DI1206,320266 (225–315)192 (162–229)198 (171–231)145 (124–168)95 (68–116)<1 × 10−255
  • Data are medians (25th–75th percentile). Variables with nonnormal right-skewed distribution were logarithmically transformed before analyses. P values are based on the general linear model adjusted for age and BMI. DI30 = Matsuda ISI × InsAUC30/GluAUC30; DI120 = Matsuda ISI × InsAUC120/GluAUC120. Bonferroni post hoc tests: all pairwise comparisons between the categories of glucose tolerance were significant at P < 0.05, except for:

  • *P > 0.05 vs. NGT;

  • P > 0.05 vs. isolated IFG;

  • P > 0.05 vs. isolated IGT.