Table 2.
Sample characteristics at baseline
| Characteristics | All subjects (n = 23)a Mean ± SD |
CBT-I (n = 9)b Mean ± SD |
Wellness education (n = 9)b Mean ± SD |
|---|---|---|---|
| Age (years) | 63 ± 10 | 65 ± 9 | 60 ± 10 |
| Men/women (n) | 19/4 | 7/2 | 7/2 |
| FEV1, % predicted | 62 ± 18 | 62 ± 21 | 59 ± 18 |
| FEV1/FVC | 50 ± 10 | 47 ± 7 | 53 ± 14 |
| BMI | 25 ± 5 | 27 ± 6 | 24 ± 3 |
| Race (n) | |||
| African-American | 5 | 1 | 4 |
| Caucasian | 18 | 8 | 5 |
| Other | 0 | 0 | 0 |
| Educationc | |||
| Less than high school | 2 | 1 | 0 |
| High school | 5 | 4 | 1 |
| Some college | 8 | 4 | 4 |
| College | 7 | 1 | 4 |
| Employmentc | |||
| Retired | 6 | 3 | 1 |
| Part-time | 5 | 2 | 2 |
| Full time | 1 | 1 | 0 |
| Unemployed | 10 | 3 | 6 |
| Smoking, pack-years | 46 ± 20 | 48 ± 32 | 41 ± 8 |
| PSG, apnea/hypopnea index | 4 ± 3 | 5 ± 3 | 3.5 ± 2 |
| PSG, periodic limb movement arousal index (per hour) | 1.0 ± 2 | 0.47 ± 0.6 | 1.5 ± 2 |
| PSG, mean SaO2 | 94 ± 2 | 95 ± 3 | 94 ± 1 |
| PSG, minimum SaO2 | 86 ± 5 | 85 ± 5 | 86 ± 5 |
| Excessive daytime sleepiness (Epworth Sleepiness Scale) | 9.2 ± 5 | 8.0 ± 4.3 | 11 ± 5 |
a
Notes: Includes all subjects (CBT-I and WE, Phases 1 and 2);
b
includes subjects randomized to CBT-I or WE (Phase 2);
c
data missing for one subject.
Abbreviations: BMI, body mass index; CBT-I, cognitive behavioral therapy for insomnia; FEV1/FVC, forced expiratory volume in 1 second/forced vital capacity; PSG, programmable sound generator; WE, wellness education; SD, standard deviation.