Characteristics of the cross-sectional and longitudinal samples
| Cross-sectionala | Longitudinal (N = 332)b | ||
|---|---|---|---|
| (N = 572) | Baseline | Follow-up | |
| Sex | |||
| Male | 300 (52.4%) | 178 (53.6%) | 178 (53.6%) |
| Female | 272 (47.6%) | 154 (46.4%) | 154 (46.4%) |
| Race/ethnicity | |||
| Non-Hispanic White | 424 (74.1%) | 252 (75.9%) | 252 (75.9%) |
| Racial/ethnic minority | 148 (25.9%) | 80 (24.1%) | 80 (24.1%) |
| Age | |||
| 5 | 2 (0.3%) | 6 (1.8%) | |
| 6 | 32 (5.6%) | 35 (10.5%) | |
| 7 | 38 (6.6%) | 53 (16.0%) | |
| 8 | 48 (8.4%) | 51 (15.4%) | |
| 9 | 32 (5.6%) | 72 (21.7%) | |
| 10 | 36 (6.3%) | 57 (17.2%) | |
| 11 | 28 (4.9%) | 51 (15.4%) | |
| 12 | 13 (2.3%) | 7 (2.1%) | 8 (2.4%) |
| 13 | 27 (4.7%) | 27 (8.1%) | |
| 14 | 40 (7.0%) | 40 (12.0%) | |
| 15 | 50 (8.7%) | 51 (15.4%) | |
| 16 | 59 (10.3%) | 58 (17.5%) | |
| 17 | 53 (9.3%) | 51 (15.4%) | |
| 18 | 46 (8.0%) | 45 (13.6%) | |
| 19 | 31 (5.4%) | 27 (8.1%) | |
| 20 | 21 (3.7%) | 15 (4.5%) | |
| 21 | 8 (1.4%) | 7 (2.1%) | |
| 22 23 | 7 (1.2%) 1 (0.2%) | 3 (0.9%) | |
| BMI percentile | |||
| Normal weight | 373 (65.2%) | 232 (69.9%) | 225 (67.8%) |
| Overweight | 113 (19.8%) | 36 (10.8%) | 61 (18.4%) |
| Obese | 86 (15.0%) | 64 (19.3%) | 46 (13.9%) |
| Behavioral disorders | |||
| None | 449 (78.5%) | 274 (82.5%) | 248 (74.7%) |
| Yes | 123 (21.5%) | 58 (17.5%) | 84 (25.3%) |
| Neurobehavioral measures | |||
| Attention problems, score | 54.6 (6.6) | 54.3 (6.4) | 54.8 (6.6) |
| Thought problems, score | 55.1 (6.6) | 55.4 (6.9) | 54.5 (5.8) |
| Internalizing problems, score | 50.5 (10.7) | 50.6 (10.7) | 50.4 (10.0) |
| Externalizing problems, score | 48.1 (10.8) | 48.3 (11.0) | 48.2 (10.0) |
| Verbal IQ, score | 105.8 (13.2) | 107.0 (13.2) | 102.0 (10.4) |
| Non-verbal IQ, score | 106.4 (15.5) | 108.1 (15.5) | 106.1 (11.6) |
| Coding, scaled score | 10.3 (3.2) | 10.6 (3.3) | 9.8 (2.6) |
| Digit span backward, raw score | 4.5 (1.7) | 4.6 (1.6) | 6.9 (2.4) |
| PSG | |||
| SOL, min | 27.4 (22.2) | 26.8 (22.3) | 25.0 (20.0) |
| WASO, min | 61.6 (41.0) | 43.9 (32.9) | 69.2 (41.1) |
| TST, min | 448.6 (51.3) | 461.3 (44.3) | 448.0 (49.8) |
| SE, % | 83.6 (9.3) | 86.7 (7.6) | 82.9 (9.1) |
| N1, % | 2.0 (2.7) | 3.5 (2.6) | 0.9 (1.1) |
| N2, % | 51.1 (10.9) | 46.7 (10.8) | 53.2 (9.4) |
| N3, % | 27.9 (10.1) | 29.9 (10.5) | 27.1 (9.0) |
| R, % | 19.0 (5.2) | 20.1 (5.3) | 18.8 (4.7) |
| AHI, events/h | 1.9 (4.7) | 0.8 (1.1) | 2.5 (5.7) |
↵a Data for 572 subjects in cross-sectional analyses.
↵b Data for 332 subjects in longitudinal analyses, including baseline and follow-up.
Data are means (SD) and number of cases (percentage) for continuous and categorical/ordinal variables, respectively. AHI = apnea/hypopnea index; BMI = body mass index; N1 = epochs scored as NREM stage 1; N2 = epochs scored as NREM stage 2; N3 = epochs scored as NREM stages 3 or 4; R = epochs scored as REM sleep; SE = sleep efficiency; SOL = sleep onset latency; TST = total sleep time; WASO = wake after sleep onset.