Table 2.
Polysomnographic and clinical characteristics of the sample
| Variables | Excessively Sleepy N = 69 | Moderately Sleepy N = 204 | Alert N = 345 | P Value |
|---|---|---|---|---|
| Age | 41.55 ± 10.81 | 40.43 ± 12.41 | 42.32 ± 13.39 | 0.249 |
| Gender % F | 37.7% | 52.0% | 53.9% | 0.047 |
| MSLT (min)a,b,c | 3.44 ± 1.12 | 7.62 ± 1.36 | 14.17 ± 2.82 | 0.000 |
| ESSb,c | 11.21 ± 4.38 | 9.94 ± 4.65 | 8.21 ± 4.04 | 0.000 |
| TST (min)b,c | 450.57 ± 63.01 | 441.87 ± 50.68 | 414.69 ± 68.53 | 0.000 |
| Sleep Latency (min)b,c | 10.54 ± 22.99 | 10.32 ± 9.62 | 20.24 ± 27.35 | 0.000 |
| Stage 1% | 10.84 ± 7.07 | 9.77 ± 6.64 | 11.34 ± 9.69 | 0.115 |
| Stage 2% | 63.00 ± 59.90 | 57.07 ± 9.43 | 56.60 ± 10.29 | 0.089 |
| Stage 3-4% | 13.62 ± 12.58 | 15.19 ± 10.43 | 14.18 ± 9.01 | 0.402 |
| REM % | 20.55 ± 10.37 | 17.96 ± 6.91 | 17.91 ± 6.33 | 0.017 |
| Apnea-Hypopnea Index | 2.35 ± 7.95 | 1.70 ± 5.70 | 1.66 ± 6.53 | 0.729 |
| BMI | 31.06 ± 9.12 | 30.77 ± 8.36 | 29.75 ± 7.62 | 0.260 |
| PLMAIa,b | 2.60 ± 8.81 | .68 ± 1.81 | .74 ± 2.29 | 0.000 |
| RLS symptomsb,c | 3.3% | 3.1% | 9.6% | 0.000 |
| Medical conditions (mean #) | 1.68 ± 1.84 | 1.67 ± 1.58 | 1.77 ± 1.51 | 0.753 |
| Sedating medications (mean #) | 0.26 ± 0.66 | 0.42 ± .80 | 0.43 ± 0.86 | 0.304 |
Data are presented as means ± SD. Significance was tested using ANOVA (or X2 where appropriate) with Bonferroni corrections for multiple comparisons (corrected α = 0.0025). Significance for post hoc between group comparisons are indicated as follows:
a
P < 0.05, excessively sleepy vs moderate sleepiness;
b
P < 0.05, excessively sleepy vs alert;
c
P < 0.05, moderate sleepiness vs alert; TST, total sleep time; REM, rapid eye movement sleep; AHI, apnea-hypopnea index; PLMAI, periodic limb movement arousal index; ESS, Epworth Sleepiness Scale. RLS sx, percentage of individuals endorsing restless legs syndrome symptoms usually or always from the global sleep assessment questionnaire (GSAQ).52