Table 2.
Objective, subjective sleep parameters, and depression among study groups
| APD (N = 22) | CKD 3b–5 (N = 89) | HD (N = 75) | p value | |
|---|---|---|---|---|
| Total sleep time (minutes) | 342.7 (271.7, 475.3) | 366.3 (298.3, 433.2) | 313.3 (216.2, 388.2) | 0.002 CKD > HDa |
| Sleep efficiency (%) | 78.3 (57.6, 87.1) | 77.8 (67.3, 85.1) | 69.8 (59.5, 78.9) | 0.018 CKD > HDb |
| Stage 1 (% of TST) | 7.2 (4.7, 12.4) | 10.1 (6.2, 15.9) | 11.6 (6.8, 18.1) | 0.11 |
| Stage 2 (% of TST) | 56.3 (48, 65.9) | 61.2 (53.9, 69.8) | 57.5 (51.0, 67.0) | 0.13 |
| Stages 3 and 4 (% of TST) | 14.0 (4.3, 23.4) | 5.4 (1.3, 10.9) | 7.3 (1.3, 18.5) | 0.009 APD > CKDb |
| Rapid eye movement sleep (% of TST) | 20.9 (15.8, 25.6) | 20.3 (14.5, 26) | 17.9 (11.2, 22.3) | 0.11 |
| Apnea-hypopnea index | 6.0 (2.3, 22.2) | 8.8 (3.2, 27.6) | 18.2 (6.7, 30.2) | 0.008 HD > CKDc HD > APDc |
| Obstructive apnea index | 4.9 (1.8, 18.2) | 6.2 (2.0, 17.3) | 11.3 (4.1, 23) | 0.034 HD > CKDb HD > APDb |
| Nocturnal hypoxemia (≥3 % of TST) | 1.1 (0.5, 6,7) | 3.8 (1,5, 10) | 1.5 (0.9, 8,5) | 0.01 CKD > APDb CKD > HDb |
| Micro-arousal index | 9.2 (4.7, 13.4) | 8.8 (3.9, 15.5) | 8.5 (5.4, 14.0) | 0.98 |
| Periodic limb movement index | 5.7 (1.6, 10.7) | 2.4 (0.9, 5.3) | 2.7 (0.7, 6.2) | 0.14 APD > CKDc |
| Pittsburgh Sleep Quality Index score | 8 (6.5, 13) | 6 (4, 9) | 8 (5, 11) | 0.007 APD > CKDb HD > CKDc |
| Patient Health Questionnaire-9 score | 11 (8, 14.75) | 10 (7, 13) | 8 (6.25, 12) | 0.08 |
Results are presented as medians and interquartile ranges or as percentages. Numbers in parentheses reflect the 25th and the 75th percentile of the variables. Stages 1, 2, 3, and 4, and rapid eye movement sleep are expressed as percent of total sleep time. Apnea hypopnea Index, obstructive apnea index, micro-arousal index, and periodic limb movement index are expressed as events per hour of total sleep time
Sleep efficiency percentage of total sleep time as a proportion of the total study duration, Apnea hypopnea index, number of apneas/hypopneas during total sleep time, Obstructive apnea index number of obstructive apneas per hour of total sleep time, Nocturnal hypoxemia ≥3 % total sleep time, percentage of subjects who had at least 3 % of total sleep time with oxyhemoglobin saturation less than 90 %, Micro-arousal index number of microarousals/hour of sleep, Periodic limb movement index number of periodic limb movements per hour of total sleep time
a p < 0.001; b p < 0.01; c p < 0.05 for the pairwise comparisons