TABLE 1.
Demographics and overnight PSG measurements in normal controls and chronic insomniacs.
| Normal controls (n = 21) | Chronic insomniacs (n = 31) | ν | t/χ2/u | P | |
| Age (y)u | 34.76 (8.38) | 35.68 (10.69) | – | 312.500 | 0.808 |
| Sex (m/f)χ2 | 3/18 | 10/21 | 1 | 2.157 | 0.142 |
| MSL (min)t | 12.20 (3.86) | 14.97 (3.42) | 51 | –2.716 | 0.009* |
| ESSu | 7.24 (4.25) | 5.81 (5.08) | – | 262.000 | 0.235 |
| TST (min)u | 447.85 (43.49) | 399.19 (83.87) | – | 191.00 | 0.012* |
| SE (%)u | 88.51 (7.86) | 78.31 (16.09) | – | 177.000 | 0.006* |
| SOL (min)u | 12.52 (13.79) | 31.88 (55.42) | – | 434.500 | 0.042* |
| WASO (min)u | 45.07 (32.74) | 75.61 (57.46) | – | 423.500 | 0.068 |
| NREM (min)t | 355.01 (30.39) | 322.26 (63.93) | 45.722 | 2.470 | 0.017* |
| N1 (min)u | 70.26 (42.37) | 61.94 (26.71) | – | 305.500 | 0.709 |
| N2 (min)t | 251.68 (39.62) | 235.02 (68.61) | 48.995 | 1.106 | 0.274 |
| N3 (min)u | 33.10 (25.22) | 25.10 (25.49) | – | 251.500 | 0.167 |
| REM (min)t | 90.25 (28.98) | 77.05 (34.11) | 51 | 1.453 | 0.153 |
PSG, polysomnography; TST, total sleep time; SOL, sleep onset latency; WASO, wake after sleep onset; N1, duration of non-rapid eye movement sleep stage 1; N2, duration of non-rapid eye movement sleep stage 2; N3, duration of non-rapid eye movement sleep stage 3; NREM, time of whole non-rapid eye movement sleep; REM, rapid eye movement sleep time; SE, sleep efficiency; MSL, mean sleep latency of four multiple sleep latency tests; ESS, Epworth Sleepiness Scale.
*P ≤ 0.05; t, comparison between Normal Controls and Chronic Insomniacs by Independent t-test; u, comparison between Normal Controls and Chronic Insomniacs by Mann-Whitney U test; χ2, comparison between Normal Controls and Chronic Insomniacs by Chi-square (χ2) test.