Table 1 Baseline characteristics of study participants according to HbA1c levels at baseline
Variables | Total (N = 9294) | HbA1c in participants without known diabetes | p trend | Known diabetes (n = 604) | ||||
|---|---|---|---|---|---|---|---|---|
< 5.0% | 5.0–5.4% | 5.5–5.9% | 6.0–6.4% | ≥ 6.5% | ||||
(n = 303) | (n = 2962) | (n = 3930) | (n = 1038) | (n = 457) | ||||
Age, years | 52.0 ± 8.9 | 48.5 ± 7.6 | 49.5 ± 8.2 | 52.4 ± 8.9 | 54.6 ± 8.5 | 55.2 ± 8.8 | < 0.001 | 56.5 ± 8.6 |
Men | 4458 (48.0) | 132 (43.6) | 1387 (46.8) | 1904 (48.5) | 498 (48.0) | 211 (46.2) | 0.362 | 326 (54.0) |
Body mass index, kg/m2 | 24.6 ± 3.1 | 23.8 ± 2.8 | 23.9 ± 2.9 | 24.6 ± 3.1 | 25.5 ± 3.1 | 26.3 ± 3.3 | < 0.001 | 25.3 ± 3.1 |
Waist circumference, cm | 82.6 ± 8.8 | 80.0 ± 8.5 | 80.0 ± 8.5 | 82.6 ± 8.6 | 85.7 ± 8.3 | 88.5 ± 7.9 | < 0.001 | 86.5 ± 7.9 |
Fasting Glucose, mg/dL | 82 [77, 90] | 79 [74, 84] | 80 [76, 85] | 82 [77, 89] | 87 [81, 95] | 108 [94, 130] | < 0.001 | 119 [94, 158] |
HbA1c, % | 5.8 ± 0.9 | 4.8 ± 0.3 | 5.3 ± 0.1 | 5.7 ± 0.1 | 6.1 ± 0.1 | 7.4 ± 1.2 | < 0.001 | 7.9 ± 1.9 |
RBC count, Mil/µL | 4.42 ± 0.47 | 4.32 ± 0.52 | 4.38 ± 0.47 | 4.42 ± 0.46 | 4.47 ± 0.46 | 4.53 ± 0.46 | < 0.001 | 4.49 ± 0.50 |
Haemoglobin, g/dL | 13.6 ± 1.6 | 13.5 ± 1.7 | 13.6 ± 1.6 | 13.6 ± 1.6 | 13.6 ± 1.6 | 13.8 ± 1.5 | 0.063 | 13.8 ± 1.6 |
Haematocrit, % | 41.0 ± 4.6 | 40.4 ± 4.9 | 40.9 ± 4.5 | 41.0 ± 4.6 | 41.2 ± 4.7 | 41.7 ± 4.3 | < 0.001 | 41.7 ± 4.7 |
Total bilirubin, mg/dL | 0.53 [0.40, 0.73] | 0.64 [0.48, 0.92] | 0.57 [0.43, 0.78] | 0.52 [0.38, 0.69] | 0.49 [0.37, 0.66] | 0.50 [0.39, 0.71] | < 0.001 | 0.50 [0.38, 0.69] |
ALT, IU/L | 22 [17, 31] | 21 [16, 29] | 21 [16, 28] | 22 [18, 31] | 25 [19, 34] | 30 [22, 44] | < 0.001 | 27 [20, 36] |
AST, IU/L | 26 [23, 32] | 25 [21, 32] | 26 [22, 31] | 27 [23, 32] | 27 [24, 32] | 29 [24, 38] | < 0.001 | 26 [22, 33] |
Systolic blood pressure, mmHg | 121.3 ± 18.4 | 117.8 ± 17.7 | 118.0 ± 17.6 | 121.3 ± 18.2 | 124.5 ± 18.4 | 129.5 ± 19.2 | < 0.001 | 127.8 ± 18.9 |
Diastolic blood pressure, mmHg | 80.2 ± 11.4 | 78.2 ± 12.2 | 78.6 ± 11.4 | 80.5 ± 11.4 | 81.8 ± 11.3 | 84.5 ± 10.7 | < 0.001 | 81.7 ± 10.7 |
Hypertension | 2770 (29.8) | 76 (25.1) | 693 (23.4) | 1234 (31.4) | 403 (38.8) | 219 (47.9) | < 0.001 | 314 (52.0) |
Dyslipidaemia | 4592 (49.4) | 103 (34.0) | 1204 (40.7) | 1977 (50.3) | 622 (59.9) | 326 (71.3) | < 0.001 | 403 (66.7) |
Liver diseases | 411 (4.4) | 26 (8.6) | 138 (4.7) | 147 (3.7) | 41 (4.0) | 15 (3.3) | 0.002 | 44 (7.3) |
Anaemia | 1321 (14.2) | 47 (15.5) | 417 (14.1) | 592 (15.1) | 139 (13.4) | 54 (11.8) | 0.271 | 72 (11.9) |
Smoking status | < 0.001 | |||||||
Never smoker | 5450 (58.6) | 195 (64.4) | 1819 (61.4) | 2266 (57.7) | 581 (56.0) | 265 (58.0) | 324 (53.6) | |
Past smoker | 1428 (15.4) | 53 (17.5) | 457 (15.4) | 587 (14.9) | 147 (14.2) | 58 (12.7) | 126 (20.9) | |
Current smoker | 2416 (26.0) | 55 (18.2) | 686 (23.2) | 1077 (27.4) | 310 (29.9) | 134 (29.3) | 154 (25.5) | |
Alcohol use | < 0.001 | |||||||
Never alcohol drinker | 4262 (45.9) | 125 (41.3) | 1316 (44.4) | 1819 (46.3) | 480 (46.2) | 230 (50.3) | 292 (48.3) | |
Past alcohol drinker | 589 (6.3) | 18 (5.9) | 144 (4.9) | 257 (6.5) | 77 (7.4) | 34 (7.4) | 59 (9.8) | |
Current alcohol drinker | 4443 (47.8) | 160 (52.8) | 1502 (50.7) | 1854 (47.2) | 481 (46.3) | 193 (42.2) | 253 (41.9) | |
Regular exercise | 2613 (28.1) | 81 (26.7) | 875 (29.5) | 1065 (27.1) | 251 (24.2) | 130 (28.5) | 0.031 | 211 (34.9) |
Higher education | 1254 (13.5) | 44 (14.5) | 440 (14.9) | 526 (13.4) | 113 (10.9) | 54 (11.8) | < 0.001 | 77 (12.8) |
Residential area | ||||||||
Ansung | 4532 (48.8) | 127 (41.9) | 1289 (43.5) | 1968 (50.1) | 557 (53.7) | 253 (55.4) | < 0.001 | 338 (56.0) |
Ansan | 4762 (51.2) | 176 (58.1) | 1673 (56.5) | 1962 (49.9) | 481 (46.3) | 204 (44.6) | 266 (44.0) | |