Table 2.
Baseline demographic and sleep characteristics by ethnicity.
| Characteristics | Non-Hispanic White (n=29) | African American (n=28) | P valuea | |
| Age (years), mean (SD) | 32.07 (10.84) | 38.00 (14.10) | .08 | |
| Gender (female), n (%) | 11 (38) | 16 (57) | .15 | |
| BMI (kg/m2), mean (SD) | 25.47 (4.12) | 29.87 (6.20) | .003 | |
| Physical activity (days/week), mean (SD) | 3.86 (2.21) | 2.74 (1.75) | .04 | |
| Annual income (US$), n (%) | .31 | |||
|
|
<15,000 | 45 (13) | 7 (25) |
|
|
|
15,000-29,999 | 9 (31) | 11 (39) |
|
|
|
30,000-49,999 | 5 (17) | 5 (18) |
|
|
|
50,000-74,999 | 0 (0) | 2 (7) |
|
|
|
>75,000 | 1 (3) | 0 (0) |
|
|
|
Not reported | 1 (3) | 3 (11) |
|
| Education, n (%) | .001 | |||
|
|
High school | 0 (0) | 5 (8) |
|
|
|
Trade school | 1 (3) | 9 (32) |
|
|
|
College educated | 21 (72) | 11 (39) |
|
|
|
Not reported | 7 (24) | 3 (11) |
|
| Actigraphy indices, mean (SD) | ||||
|
|
Sleep efficiency (%) | 89.36 (4.71) | 84.21 (7.48) | .003 |
|
|
Sleep duration (min/night) | 413.25 (42.58) | 341.00 (59.33) | .001 |
|
|
Sleep fragmentation (units) | 24.34 (5.39) | 29.57 (10.03) | .02 |
| Pittsburgh Sleep Quality Index domains, mean (SD) | ||||
|
|
Sleep quality | 1.9 (1.4) | 2.7 (1.3) | .03 |
|
|
Sleep efficiency | 0.8 (0.7) | 1.8 (0.9) | <.001 |
|
|
Daily disturbances | 2.0 (1.1) | 2.0 (1.0) | .89 |
|
|
Global score | 4.7 (2.5) | 6.5 (2.5) | .008 |
aP values were calculated using the analysis of variance and chi-square tests (n=57).