Table 1.
Demographic and clinical characteristics of study participants by QTc interval category
| QTc interval >440ms | QTc interval ≤440ms | ||
|---|---|---|---|
| Characteristic | n = 104 | n = 195 | p value |
| Age in years, mean (±SD) | 51.3 (±9.4) | 49.5 (±10.0) | 0.136 |
| Female sex, n (%) | 87 (83.7) | 121 (62.1) | <0.001 |
| Height in meters, mean (±SD) | 1.62 (0.07) | 1.62 (0.09) | 0.798 |
| Weight in kg, mean (±SD) | |||
| BMI in kg/m2, mean (±SD) | 27.9 (±6.1) | 27.2 (±5.1) | 0.300 |
| Waist circumference in cm, mean (±SD) | 99.0 (±14.0) | 97.8 (±13.4) | 0.460 |
| Ever smoked, n (%) | 26 (25.0) | 43 (22.1) | 0.564 |
| Duration of diabetes in year, median (IQR) | 4 (2.9) | 4 (1.8) | 0.237 |
| Vigorous physical activity (≥600 METS/week) (%) | 66 (63.5) | 107 (54.9) | 0.152 |
| Fasting blood sugar in mmol/L, mean (±SD) | 11.3 (±5.1) | 11.1 (±4.7) | 0.669 |
| HbA1c (%), mean (±SD) | 9.6 (±2.6) | 9.8 (±2.6) | 0.505 |
| History of hypertension, n (%) | 82 (78.9) | 125 (64.1) | 0.009 |
| Resting systolic blood pressure in mmHg, mean (±SD) | 146 (±23) | 140 (±22) | 0.030 |
| Resting diastolic blood pressure in mmHg, mean (±SD) | 89 (±10) | 86 (±11) | 0.023 |
| Mean arterial pressure in mmHg, mean (±SD) | 108 (±13) | 104 (±13) | 0.014 |
| Pulse pressure in mmHg, mean (±SD) | 57 (±18) | 54 (±18) | 0.165 |
| Presence of diabetic retinopathy, n (%) | 0.790 | ||
| None | 81 (77.9) | 150 (76.9) | |
| Non-proliferative | 19 (18.3) | 34 (17.4) | |
| Proliferative | 4 (3.9) | 11 (5.6) | |
| Symptoms of neuropathy in past 6 months n (%) | |||
| Palpitations | 58 (55.8) | 91 (46.7) | 0.134 |
| Fainting | 41 (39.4) | 73 (37.4) | 0.736 |
| Numbness in feet | 67 (64.4) | 116 (59.5) | 0.404 |
| Use of antihypertensive drugs n (%) | 0.246 | ||
| None | 3 (5.5) | 14 (17.5) | |
| Diuretic | 6 (10.9) | 7 (8.8) | |
| Beta blocker | 3 (5.5) | 6 (7.5) | |
| Calcium channel blocker | 44 (32.6) | 21 (26.3) | |
| ACEI/ARB | 17 (30.9) | 25 (31.3) |
SD standard deviation, IQR inter-quartile range, METS metabolic equivalents, ACEI angiotensin-converting enzyme inhibitors, ARB angiotensin receptor blockers