Table 1.
Baseline characteristics.
| Normal − FPG < 100 mg/dL, A1c < 5.7% (n = 1585) | Pre-DM overall (n = 755) | IFG-only − 100 < FPG < 125 mg/dL, A1c < 5.7% (n = 329) | HbA1c-only − FPG < 100 mg/dL, 5.7% < A1c < 6.5% (n = 222) | Both − 100 < FPG < 125 mg/dL, 5.7% < A1c < 6.5% (n = 204) | Pre-DM versus normal | IFG versus HbA1c versus both | |
|---|---|---|---|---|---|---|---|
| Age (years) | 47 (39, 55) | 52 (44, 60) | 53 (45, 60) | 51 (43, 59) | 53 (45, 61) | <0.0001 | 0.06 |
| Men (%) | 37 | 47 | 52 | 42 | 44 | <0.0001 | 0.21 |
| Race/ethnicity (%) | |||||||
| African American | 47 | 53 | 33 | 74 | 61 | 0.002 | <0.001 |
| Caucasian | 38 | 28 | 46 | 13 | 19 | <0.0001 | <0.001 |
| Hispanic | 14 | 16 | 19 | 10 | 17 | 0.15 | 0.01 |
| Other | 2 | 2 | 2 | 2 | 3 | 0.28 | <0.001 |
| BMI (kg/m2) | 28 (25, 33) | 31 (27, 37) | 29 (26, 34) | 32 (27, 38) | 34 (30, 39) | <0.0001 | <0.001 |
| Waist circumference (cm) | 91 (83, 102) | 99 (89, 109) | 95 (88, 105) | 99 (88, 111) | 104 (94, 114) | <0.0001 | <0.001 |
| Smoking (%) | 24 | 23 | 20 | 30 | 20 | 0.04 | 0.004 |
| FamHx heart disease (%) | 32 | 35 | 31 | 41 | 35 | <0.0001 | 0.40 |
| Framingham 10-year CHD risk (%) | 1 (0, 4) | 3 (1, 8) | 4 (1, 8) | 2 (1, 6) | 4 (1, 8) | <0.0001 | 0.03 |
| Systolic BP (mm Hg) | 126 (115, 138) | 133 (121, 146) | 131 (119, 146) | 133 (122, 146) | 133 (123, 147) | <0.0001 | 0.24 |
| Diastolic BP (mm Hg) | 80 (74, 86) | 81 (75, 88) | 80 (75, 87) | 83 (77, 90) | 82 (76, 88) | <0.0001 | 0.04 |
| Total cholesterol (mg/dL) | 190 (166, 216) | 193 (170, 220) | 194 (172, 223) | 190 (169, 217) | 193 (167, 219) | 0.03 | 0.31 |
| HDL-C (mg/dL) | 52 (44, 62) | 48 (41, 57) | 49 (41, 60) | 49 (42, 57) | 46 (41, 55) | <0.0001 | 0.03 |
| LDL-C (mg/dL) | 114 (93, 137) | 116 (95, 143) | 117 (95, 141) | 114 (99, 144) | 117 (92, 145) | 0.02 | 0.93 |
| TG (mg/dL) | 93 (68, 132) | 112 (80, 159) | 114 (82, 156) | 99 (74, 143) | 127 (87, 174) | <0.0001 | 0.002 |
| HbA1c (%) | 5.3 (5.1, 5.5) | 5.8 (5.5, 6) | 5.4 (5.2, 5.6) | 5.9 (5.8, 6) | 6 (5.9, 6.1) | <0.0001 | <0.001 |
| Fasting glucose (mg/dL) | 89 (84, 94) | 102 (96, 107) | 103 (101, 107) | 91 (86, 95) | 106 (103, 112) | <0.0001 | <0.001 |
Continuous variables are presented as medians with interquartile ranges. Categorical variables are presented as percent prevalence. Kruskal–Wallis test for continuous variables and Pearson’s chi-square test for categorical variables.
FPG: fasting plasma glucose; HbA1c: haemoglobin A1c; Pre-DM: prediabetes; IFG: impaired fasting glucose; BMI: body mass index; CHD: coronary heart disease; BP: blood pressure; HDL-C: high-density lipoprotein cholesterol; LDL-C: low-density lipoprotein cholesterol; TG: triglyceride.