Table 1.
Polysomnographic parameters measured in young adults, older adults, and oldest old individuals.
| Polysomnographic parameter | YA (N = 15) | OA (N = 13) | OO (N = 10) | F(2, 35) or χ2b | p | Post-hoc p-value | ||
|---|---|---|---|---|---|---|---|---|
| Mean (SD) | Mean (SD) | Mean (SD) | YA × OA | YA × OO | OA × OO | |||
| Sleep latency (min) | 20.4 (23.5) | 13.5 (11.4) | 41.4 (43.9) | 4.004 | 0.135 | NS | ||
| REM sleep latency (min)a | 96.5 (28.3) | 100.8 (49.0) | 182.0 (102.3) | 7.229 | 0.027 | 0.662 | 0.006 | 0.043 |
| Total sleep time (min) | 383.0 (29.5) | 343.8 (55.9) | 198.6 (90.5) | 21.522 | <0.001 | 0.048 | <0.001 | 0.001 |
| Sleep efficiency (%) | 89.4 (6.0) | 77.4 (12.7) | 45.7 (19.4) | 23.377 | <0.001 | 0.008 | <0.001 | 0.001 |
| Stage N1 % | 7.6 (2.6) | 16.7 (7.3) | 27.5 (20.1) | 18.889 | <0.001 | <0.001 | 0.002 | 0.163 |
| Stage N2 % | 47.3 (7.6) | 42.7 (7.9) | 43.5 (9.2) | 1.292 | 0.287 | NS | ||
| Stage N3 % | 25.7 (5.6) | 20.6 (6.6) | 19.1 (17.5) | 1.472 | 0.243 | NS | ||
| Stage REM % | 19.5 (4.2) | 20.0 (5.7) | 9.9 (8.8) | 9.092 | 0.011 | 0.534 | 0.007 | 0.011 |
| Minutes awake | 29.5 (15.0) | 88.5 (56.7) | 172.5 (66.1) | 23.173 | <0.001 | 0.001 | <0.001 | 0.008 |
| Arousals/h | 8.8 (2.8) | 23.8 (11.2) | 31.6 (26.1) | 17.863 | <0.001 | <0.001 | 0.002 | 0.804 |
| Periodic limb movements/h | 0.1 (0.3) | 12.8 (23.5) | 14.6 (14.2) | 12.804 | 0.002 | 0.002 | 0.001 | 0.466 |
| Apnea-hypopnea index | 1.7 (3.1) | 16.7 (17.2) | 30.3 (29.0) | 20.075 | <0.001 | <0.001 | <0.001 | 0.215 |
| Baseline SO2 (%) | 97.0 (0.9) | 94.4 (1.7) | 95.0 (2.8) | 13.308 | 0.001 | <0.001 | 0.040 | 0.264 |
| Mean SO2 (%) | 96.3 (1.0) | 94.1 (1.8) | 94.2 (2.8) | 8.728 | 0.013 | 0.002 | 0.107 | 0.804 |
| Minimum SO2 (%) | 92.8 (1.9) | 87.0 (5.6) | 88.0 (6.0) | 9.737 | 0.008 | 0.007 | 0.011 | 0.513 |
REM, rapid eye movement; min, minutes; h, hour; SO2, oxyhemoglobin saturation; SD, standard deviation; N, number of individuals; NS, non-significant; YA, young adult; OA, older adult; OO, oldest old;
a
Two individuals from the oldest old group did not reach REM sleep, so their REM sleep latency were considered as missing values and their Stage REM % were zero;
b
One-Way analysis of variance (Stage N2 % and Stage N3 %) followed by Bonferroni post-hoc test or Kruskal–Wallis test followed by pairwise Mann–Whitney tests (other variables).