Table 4. Comparisons of sleep characteristics between the RLS and non-RLS groups.
| RLS (n = 10) | Non-RLS (n = 60) | p-value | |
|---|---|---|---|
| PSQI | |||
| Global score, median (IQR) | 8.0 (4.0–14.0) | 5.5 (4.0–9.0) | 0.16 |
| Global score ≥6, n (%) | 6 (60) | 30 (50) | 0.56 |
| PSQI components, n (%) | |||
| C1: subjective sleep quality ≥2 | 3 (30) | 14 (23) | 0.64 |
| C2: sleep latency ≥2* | 4 (40) | 15 (25) | 0.32 |
| C3: sleep duration ≥2** | 8 (80) | 19 (32) | 0.004 |
| C4: habitual sleep efficiency ≥2*** | 1 (10) | 4 (6.7) | 0.71 |
| C5: sleep disturbances ≥2 | 7 (70) | 37 (62) | 0.61 |
| C6: use of sleeping medication ≥2**** | 2 (20) | 12 (20) | 1.00 |
| C7: daytime dysfunction ≥2 | 1 (10) | 3 (5.0) | 0.53 |
| ISS, median (IQR) | 5.5(3.0–8.5) | 4.0 (2.0–6.0) | 0.25 |
| ISS ≥10, n (%) | 2 (20.0) | 8 (13.3) | 0.63 |
| Symptoms of insomnia, n (%) | |||
| Difficulty initiating sleep | 7 (70) | 23 (38) | 0.06 |
| Difficulty maintaining sleep | 4 (40) | 24 (40) | 1.00 |
| Waking up too early | 1 (10) | 19 (31) | 0.16 |
| Any symptoms, mild to very severe | 7 (70) | 31 (52) | 0.28 |
| ESS, median (IQR) | 5.0 (3.25–7.75) | 5.0 (3.00–8.75) | 0.93 |
| ESS ≥10, n (%) | 2 (20.0) | 11 (18.3) | 1.00 |
*Sleep latency ≥31 min and the presence of difficulty initiating sleep.
**Total sleep time <6 hr.
***Sleep efficiency <85%.
**** >1 time. P-values were determined by nonparametric Wilcoxon rank sum test and Fisher's exact test. ESS: Epworth Sleepiness Scale, ISS: Insomnia Severity Index, PSQI: Pittsburgh Sleep Quality Index.