Table 3.
Polysomnographic parameters and EDS results for all study groups
| Parameter | CKD Stage 4 to 5 (n = 89) | HD (n = 75) | Sleep-SCORE Controls (n = 224) | P |
|---|---|---|---|---|
| TST (minutes) | 366.3 (298.3, 433.2) | 313.3 (216.2, 388.2) | 374 (314.3, 421.1) | <0.001 |
| CKD > HDa controls > HDa | ||||
| Sleep efficiency (%) | 77.8 (67.3, 85.1) | 69.8 (59.5, 78.9) | 79.3 (70.1, 86.3) | <0.001 |
| CKD > HDb controls > HDa | ||||
| Stage 1 (% TST) | 10.1 (6.2, 15.9) | 11.6 (6.8, 18.1) | 8.7 (5.5, 12.5) | 0.014 |
| Controls > HDb | ||||
| Stage 2 (% TST) | 61.2 (53.9, 69.8) | 57.5 (51, 67) | 63.5 (56.5, 68.4) | 0.004 |
| Controls > HDb | ||||
| Stage 3 and 4 (% TST) | 5.4 (1.3, 10.9) | 7.3 (1.3, 18.5) | 2.5 (0.3, 8) | <0.001 |
| CKD > controlsb HD > controlsa | ||||
| REM (% TST) | 20.3 (14.5, 26) | 17.9 (11.2, 22.3) | 21.8 (17.2, 26.2) | <0.001 |
| Controls > HDa | ||||
| AHI | 8.8 (3.2, 27.6) | 18.2 (6.7, 30.2) | 8.6 (4.3, 16.4) | <0.001 |
| HD > CKDc HD > controlsa | ||||
| AHI ≥ 30 | 20 (22.5%) | 19 (25.7%) | 25 (11.5%) | 0.002 |
| CKD > controlsb HD > controlsb | ||||
| Arousal index | 8.9 (5.4, 13.4) | 8.8 (3.9, 15.5) | 8.5 (5.4, 13.9) | 0.94 |
| Type of apnea | ||||
| obstructive apnea index | 6.2 (2, 17.3) | 11.3 (4.1, 23) | 6 (2.6, 13.2) | 0.006 |
| HD > controlsb HD > CKDc | ||||
| central apnea index | <0 (0, 0.3) | 0.2 (0, 0.7) | <0 (0, 0.2) | 0.001 |
| HD > controlsa HD > CKDc | ||||
| mixed apnea index | <0 (0, 0.2) | <0 (0, 0.3) | <0 (0, 0.2) | 0.34 |
| nocturnal hypoxemia ≥ 3% TST | 28 (37.8%) | 39 (54.9%) | 49 (27.1%) | <0.001 |
| HD > controlsa HD > CKDc | ||||
| Self-reported sleep | ||||
| ESS ≥ 10 | 24 (29.3%) | 28 (40.6%) | 74 (33.0%) | 0.33 |
Results are presented as medians and interquartile ranges or as percentages. Numbers in parentheses reflect the 25th and the 75th percentile of the variables. REM, rapid eye movement; sleep efficiency, percentage of TST as a proportion of the total study duration; AHI ≥ 30, percentage of subjects who had at least 30 apneas/hypopneas during TST; obstructive apnea index, number of obstructive apneas per hour of TST; central apnea index, number of central apneas per hour of TST; mixed apnea index, number of obstructive and central apneas per hour of TST; nocturnal hypoxemia ≥ 3% TST, percentage of subjects who had at least 3% of TST with oxyhemoglobin saturation <90%.
P < 0.001;
P < 0.01;
P < 0.05 for the pairwise comparisons.