Table 1.
Characteristics of participants in normoglycemia, iIFG, and IGT
| Characteristic | Normoglycemia* (n = 2,205) | iIFG† (n = 641) | IGT‡ (n = 341) |
|---|---|---|---|
| Age (years), mean (SD) | 37.6 (10.8)§ | 40.9 (10.3)¶ | 43.7 (12.5)⊥ |
| Age (years), median (IQR) | 36.0 (30.0, 44.0)§ | 40.0 (33.0, 48.0)¶ | 42.0 (35.0, 51.0)⊥ |
| Sex, n (%) | |||
| Male | 924 (41.9)§ | 183 (28.5)¶ | 160 (46.9)⊥ |
| Female | 1,281 (58.1) | 458 (71.5) | 181 (53.1) |
| Family history of diabetes§, n (%) | 745 (33.8)§ | 237 (37.0) | 139 (40.8) |
| Weight (kg), mean (SD) | 61.6 (12.0)§ | 65.5 (12.2)¶ | 66.3 (12.0) |
| Height (cm), mean (SD) | 157.1 (8.9)§ | 155.1 (8.4)¶ | 156.9 (9.0) |
| BMI (kg/m2), mean (SD) | 25.0 (4.7)§ | 27.2 (4.6)¶ | 27.0 (4.7) |
| Waist circumference (cm), mean (SD) | |||
| Overall | 81.6 (11.1)§ | 85.7 (10.4)¶ | 88.1 (10.6)⊥ |
| Male | 84.8 (10.7)§ | 89.5 (10.3)¶ | 90.9 (10.8) |
| Female | 79.5 (10.8)§ | 84.2 (10.1)¶ | 85.7 (9.8) |
| Total cholesterol (mg/dL), mean (SD) | 180.4 (36.3)§ | 187.4 (37.1)¶ | 189.9 (34.3) |
| Triglycerides (mg/dL), median (IQR) | 107.0 (78.0, 150.0)§ | 124.0 (89.0, 171.0)¶ | 137.0 (100.0, 186.0)⊥ |
| LDL cholesterol (mg/dL), mean (SD) | 111.7 (28.9)§ | 118.2 (31.6)¶ | 117.5 (27.9) |
| HDL cholesterol (mg/dL), mean (SD) | |||
| Overall | 41.1 (9.5) | 40.1 (8.2)¶ | 40.3 (10.4) |
| Male | 39.6 (10.6) | 37.8 (8.3) | 39.7 (12.0) |
| Female | 42.1 (8.5) | 41.1 (7.9) | 40.8 (10.4) |
| FPG (mg/dL), mean (SD); median (IQR) | 90.0 (7.1)§; 90.0 (85.0, 95.0)§ | 102.7 (7.9)¶; 103.0 (100.0, 107.0)¶ | 98.3 (10.0)⊥; 98.0 (91.0, 106.0)⊥ |
| Glucose level at 30 min (mg/dL), mean (SD); median (IQR) | 140.7 (28.2)§; 140.0 (119.0, 160.0)§ | 164.0 (29.5)¶; 165.0 (144.0, 185.0)¶ | 174.4 (30.0)⊥; 176.0 (155.0, 193.0)⊥ |
| Glucose level at 120 min (mg/dL), mean (SD); median (IQR) | 94.7 (20.9)§; 94.0 (81.0, 107.0)§ | 107.1 (22.7)¶; 106.0 (93.0, 122.0)¶ | 138.6 (29.1)⊥; 143.0 (116.0, 159.0)⊥ |
| HbA1c (%), mean (SD); median (IQR) | 5.6 (0.4)§; 5.6 (5.3, 5.8)§ | 5.8 (0.4)¶; 5.8 (5.6, 6.1)¶ | 5.9 (0.4); 5.9 (5.6, 6.1) |
| HbA1c (mmol/mol), mean (SD); median (IQR) | 38 (0.4)§; 38 (34, 40)§ | 40 (0.4)¶; 40 (38, 43)¶ | 41 (0.4); 41 (38, 43) |
| Insulin, fasting (pmol/L), median (IQR) | 6.4 (4.4, 9.4) | 7.7 (5.5, 10.8)¶ | 8.5 (6.7, 11.2) |
| Insulin level at 30 min (pmol/L), median (IQR) | 46.6 (32.2, 72.8) | 48.2 (33.7, 71.5) | 53.1 (35.6, 76.2) |
| Insulin level at 120 min (pmol/L), median (IQR) | 31.4 (22.4, 51.0)§ | 40.0 (26.3, 65.0)¶ | 59.6 (37.8, 98.6) |
| HOMA-IR** (μIU/mL*mmol/L), median (IQR) | 1.4 (1.0, 2.1)§ | 2.0 (1.4, 2.8)¶ | 2.1 (1.6, 2.8) |
| HOMA-ↆ (μIU/mL/mmol/L), median (IQR) | 89.0 (61.2, 130.9) | 69.3 (48.9, 101.1)¶ | 91.5 (66.2, 129.9)⊥ |
| DIo‡‡, median (IQR) | 0.1 (0.1, 0.3)§ | 0.1 (0.1, 0.2)¶ | 0.1 (0.0, 0.1)⊥ |
| Insulinogenic Index§§, median (IQR) | 0.9 (0.5, 1.8)§ | 0.7 (0.4, 1.3)¶ | 0.6 (0.4, 1.0)⊥ |
DIo, Oral Disposition Index; FPG, fasting plasma glucose; IQR, interquartile range; IR, insulin resistance.
Normoglycemia defined as FPG <5.6 mmol/L (100 mg/dL) and 2-hour postload glucose (2h-PG) <7.8 mmol/L (140 mg/dL) and no medication.
IFG defined as FPG between 5.6 and 6.9 mmol/L (100–125 mg/dL) and 2h-PG <7.8 mmol/L (140 mg/dL) and no medication.
IGT defined as FPG <7.0 mmol/L (126 mg/dL) and 2h-PG between 7.8–11.0 mmol/L (140–199 mg/dL) and no medication.
Significant P value for normoglycemia versus IGT.
Significant P value for normoglycemia versus iIFG.
Significant P value for iIFG versus IGT.
Diabetes defined as FPG ≥7.0 mmol/L (126 mg/dL) or 2-h PG ≥11.1 mmol/L (200 mg/dL) or HbA1c ≥6.5% (48 mmol/mol) or on medication.
HOMA-IR = fasting insulin (μU/L) × fasting glucose (nmol/L)/22.5 or (I0(μIU/mL) × G0 (mmol/L)/22.5).
HOMA-B = (20 × insulin)/(glucose − 3.5) or (20 × I0(μIU/mL)/G0 (mmol/L) − 3.5).
DIo = (ΔI0 − 30/ΔG0 − 30) × (1/fasting insulin).
Insulinogenic Index = (ΔI0–30/ΔG0–30) where ΔI0–30 = insulin at 30 min minus fasting insulin; ΔG0–30 = glucose at 30 min minus FPG.