Table 1.
Demographic, BMI, and Sleep Characteristics of Sample at Baseline
| Characteristic | Completers (N = 29) |
Adherent (N = 11) |
Non Adherent (N = 9) |
Test Statistic1 |
|---|---|---|---|---|
| Sex: % male | 58.6 | 54.5 | 55.6 | p = 0.658 |
| Age: mean (SD), in years | 11.9 (2.7) | 10.7 (2.2) | 14.7 (1.1) | t = 5.1** |
| Ethnicity: % white | 42.9 | 54.5 | 50.0 | p = 0.605 |
| Household Income: % Below $20,000 | 30.8 | 45.5 | 42.9 | p = 0.648 |
| ESS Total, mean (SD)2 | 12.7 (5.4) | 13.2 (5.1) | 16.4 (4.6) | t = 1.4 |
| BMI: mean (SD) (age and gender adjusted) | 36.1 (11.9) | 37.7 (11.1) | 38.4 (14.3) | F(l,16) = 0.01 |
| BMI z-score mean (SD) | 2.29 (0.16) | MED = 2.5 | MED = 2.9 | U = 26.0 |
| Polysomnography Data | ||||
| Total Sleep Time (min; mean (SD)) | 445.3 (54.2) | 455.0 (51.1) | 445.2 (27.9) | t = 0.544 |
| Sleep Efficiency % mean (SD) | 85.4 (10.6) | MED=93.6 | MED=89.9 | U = 53.5 |
| Sleep Latency (min; mean (SD)) | 16.4 (15.2) | MED=12.5 | MED=7.0 | U = 67.0 |
| Awakenings (count mean (SD)) | 24.0 (11.4) | 21.0(11.5) | 28.2 (11.7) | t = 1.4 |
| Stage 1 Sleep (%mean (SD)) | 8.0 (5.0) | 6.5 (3.9) | 10.9 (5.5) | t = 2.1 |
| Stage 2 Sleep (%mean (SD)) | 49.4 (10.0) | 48.0 (11.1) | 50.4 (10.1) | t = 0.5 |
| Stage 3 Sleep (%mean (SD)) | 23.6 (9.3) | 25.2 (10.3) | 19.7 (8.2) | t = 1.3 |
| REM sleep % mean (SD) | 18.9 (6.4) | 20.3 (6.2) | 19.0 (6.8) | t = 0.4 |
| AHI mean (SD) | 10.7 (15.0) | MED=3.0 | MED=5.7 | U = 35.5 |
Note: ESS = Epworth Sleepiness Scale; BMI=Body Mass Index; MED=Median; AHI=Apnea-Hypopnea Index.
1
Test statistic compares adherent to non-adherent groups. Fisher’s exact test p values presented for categorical variables. Independent samples t or Mann Whitney U statistics presented for continuous variables, depending on distribution of outcome variable. ANCOVA used for BMI in order to covary age and gender.
2
N=10 for adherent group and N=8 for non-adherent group on this variable due to missing data.
*
p < .05.
**
p < .01.