Table 1.
Clinical and demographic characteristics of the participants
| Variable | Control | IGT | P |
|---|---|---|---|
| Subjects, n (men/women) | 20 (13/7) | 20 (16/4) | 0.28 |
| Age, years | 61.5 ± 6.0 | 62.7 ± 11.1 | 0.67 |
| Height, m | 1.7 ± 0.9 | 1.7 ± 0.07 | 0.15 |
| Weight, kg | 78.1 ± 11.5 | 94.9 ± 18.7 | 0.002 |
| BMI, kg/m2 | 27.2 ± 3.9 | 31.5 ± 5.5 | 0.008 |
| Ethnicity: Asian/European, n | 9/11 | 5/15 | 0.21 |
| 25(OH)D, nmol/l | 78.9 ± 48.8 | 50.8 ± 34.8 | 0.04 |
| 25(OH)D/BMI | 2.9 ± 1.9 | 1.6 ± 1.2 | 0.01 |
| 25(OH)D/ body surface area | 1.9 ± 0.17 | 2.1 ± 0.23 | 0.002 |
| HbA1c, mmol/mol | 38.0 ± 2.1 | 42.4 ± 6.3 | 0.007 |
| HbA1c, % | 5.6 ± 0.1 | 6.0 ± 0.57 | 0.006 |
| Cholesterol, mmol/l | 5.5 ± 0.8 | 4.7 ± 1.4 | 0.04 |
| HDL, mmol/l | 2.1 ± 3.0 | 1.2 ± 0.4 | 0.18 |
| LDL, mmol/l | 3.2 ± 0.7 | 2.1 ± 1.2 | 0.002 |
| Triglycerides, mmol/l | 1.7 ± 0.69 | 2.2 ± 1.3 | 0.22 |
| NDS (0–10) | 1.1 ± 1.2 | 3.3 ± 3.4 | 0.01 |
| VPT, Hz | 6.4 ± 3.1 | 16.9 ± 11.7 | 0.001 |
| Cold threshold, °C | 27.5 ± 2.0 | 24.9 ± 5.8 | 0.06 |
| Warm threshold, °C | 38.6 ± 2.7 | 41.2 ± 3.7 | 0.01 |
| Sensory nerve conduction velocity, m/s |
48.6 ± 4.5 | 45.8 ± 13.6 | 0.38 |
| Sural sensory nerve amplitude, µV |
13.7 ± 7.2 | 14.6 ± 14.8 | 0.82 |
| Peroneal motor nerve conduction velocity, m/s |
46.6 ± 4.7 | 41.4 ± 10.7 | 0.05 |
| Peroneal motor nerve amplitude, mV |
5.3 ± 1.8 | 3.8 ± 1.8 | 0.01 |
| Corneal nerve fibre density, number/mm2 |
35.9 ± 5.1 | 27.6 ± 8.2 | 0.001 |
| Corneal nerve branch density, number/mm2 |
94.9 ± 33.6 | 55.7 ± 35.8 | 0.001 |
| Corneal nerve fibre length, mm/mm2 |
26.7 ± 3.7 | 21.8 ± 6.5 | 0.007 |
| Corneal nerve fibre tortuosity, TC |
16.4 ± 2.7 | 18.6 ± 6.5 | 0.16 |
| Intraepidermal nerve fibre density, number/mm |
7.7 ± 2.0 | 6.7 ± 3.4 | 0.28 |
25(OH)D; 25-hydroxyvitamin D; IGT, impaired glucose tolerance; NDS, Neuropathy Disability Score; VPT, vibration perception threshold.
Values are mean ± sd, unless otherwise indicated.