Table 1.
Characteristics of participants.
| Control (n = 15) | Diabetes without DR (n = 15) | Diabetes with moderate to severe DR (n = 15) | P value | |
|---|---|---|---|---|
| Age (year) | 52.4 (6.7) | 53.7 (6.1) | 56.8 (4.7) | 0.116 |
| Female | 11 | 9 | 8 | 0.561 |
| BMI (kg/m2) | 34.3 (8.1) | 32.9 (5.6) | 30.0 (5.8) | 0.204 |
| Diabetes duration (yr) | N/A | 9.5 (6.7) | 17.3 (2.3) | 0.110 |
| HbA1c (%) | 5.4 (5.1, 5.6) | 7.8 (6.7, 10.0) | 8.8 (8.2, 10.8) | 0.059d |
| Relative PIPR | 0.36 (0.25, 0.41) | 0.29 (0.19, 0.40) | 0.10 (0.02. 0.21) | <0.001b,c |
| Melatonin variable | ||||
| aMT6s/Cr ratio (ng/mg) | 11.3 (6.6, 22.3) | 15.5 (3.5, 29.6) | 1.2 (0.4, 3.9) | <0.001b,c |
| DLMO presence | 5/6 | 6/7 | 3/9 | 0.049 |
| Sleep variables | ||||
| Insomnia severity index | 2 (1,7) | 4 (2, 8) | 10 (7, 14) | 0.001b,c |
| Sleep duration (min) | 396 (39) | 397 (69) | 387 (73) | 0.895 |
| Sleep efficiency (%) | 84 (80.87) | 86 (79, 89) | 81 (69, 86) | 0.134 |
| Sleep duration variability (min) | 65.6 (27.6) | 55.4 (21.9) | 89.3 (42.8) | 0.023c |
| Mid-sleep time (hh:mm) | 02:54 (01:06) | 3:18 (01:18) | 03:51 (01:06) | 0.104 |
| Rest-activity rhythm parameters | ||||
| IV | 0.78 (0.66, 0.84) | 0.73 (0.57, 0.92) | 0.77 (0.64, 0.88) | 0.817 |
| IS | 0.48 (0.13) | 0.43 (0.16) | 0.45 (0.15) | 0.608 |
| M10-onset (h after midnight) | 7.9 (6.1, 10.1) | 8.1 (6.3, 10.7) | 8.1 (6.9, 10.9) | 0.694 |
| L5-onset (h after noon) | 11.8 (9.9, 12.2) | 11.8 (11.1, 12.4) | 12.7 (9.8, 13.7) | 0.359 |
| RA | 0.88 (0.77, 0.93) | 0.85 (0.75, 0.89) | 0.77 (0.58, 0.85) | 0.176 |
| Sleep disordered breathing assessment | ||||
| AHI (events/h)* | 7.9 (1.8, 10.8) | 12.0 (4.8, 31.5) | 16.2 (11.6, 28.8) | 0.041b |
| Neuropathy assessment | ||||
| MNSI score | 0 (0, 0) | 1 (0, 3) | 4.5 (1.5, 6.5) | <0.001a,b,c |
| The LF/HF ratio** | 177 (54, 313) | 183 (78, 397) | 190 (94, 380) | 0.953 |
| RMSSD | 29.0 (16.0, 66.0) | 12.5 (5.8, 24.3) | 9.5 (4.3. 31.5) | 0.025a,b |
aSignificant differences between control vs T2D without DR; bsignificant differences between control vs T2D with DR, csignificant differences between T2D without DR and T2D with DR.
dComparison performed between T2D without DR and T2D with DR only.
*n = 15 for control participants, n = 14 for T2D without DR, and n = 12 for T2D with DR.
**n = 13 for control participants, n = 14 for T2D without DR, and n = 12 for T2D with DR.
AHI = apnea hypopnea index, BMI = body mass index, DLMO = dim light melatonin onset, IV = intradaily variability, IS = , interdaily stability, LF/HF ratio = low frequency/high-frequency ratio, MNSI = the Michigan Neuropathy Screening Instrument, RA = relative apmplitude, RMSSD = root mean square of the successive differences.