Table 1.
General Characteristics of the Four Groups of Children Based on the Presence or Absence of Habitual Snoring and Their Polysomnographically Derived Apnea–Hypopnea Indices
| Group 1 |
Group 2 |
Group 3 |
Group 4 |
P Value | |
|---|---|---|---|---|---|
| Nonsnoring |
Snoring |
Mild OSA |
OSA |
||
| AHI <1/h TST |
AHI <1/h TST |
AHI ≥1/h and <5/h TST |
AHI ≥5/h TST* |
||
| (n = 90) | (n = 431) | (n = 348) | (n = 141) | ||
| Age, yr | 6.86 (0.70) | 6.81 (0.70) | 6.82 (0.82) | 6.69 (1.02) | 0.480 |
| Male sex, % | 56.67% | 54.99% | 53.16% | 56.03% | 0.899 |
| Race | <0.001† | ||||
| White, n | 67 (74.44%) | 273 (63.34%) | 200 (57.47%) | 48 (30.04%) | |
| African American, n | 13 (14.44%) | 119 (27.61%) | 100 (28.74%) | 72 (51.06%) | |
| BMI Z score | 0.46 (1.33) | 0.65 (1.26) | 0.73 (1.42) | 1.25 (1.53) | <0.001† |
| Total sleep duration, min | 469.17 (47.74) | 472.62 (43.79) | 472.03 (48.07) | 460.21 (55.16) | 0.055 |
| Sleep efficiency, % | 88.75 (8.09) | 89.25 (7.63) | 90.33 (7.54) | 89.63 (8.34) | 0.172 |
| Stage 1, % | 7.31 (4.98) | 6.92 (4.90) | 6.59 (6.41) | 7.85 (6.48) | 0.239 |
| Stage 2, % | 44.99 (7.81) | 45.87 (7.87) | 44.75 (8.56) | 44.38 (7.70) | 0.137 |
| Stage SWS, % | 28.53 (6.83) | 26.05 (9.05) | 28.96 (9.24) | 26.30 (8.64) | 0.163 |
| REM sleep, % | 24.43 (14.81) | 21.57 (8.78) | 20.56 (7.59) | 21.51 (13.93) | 0.059 |
| Sleep latency, min | 26.52 (28.84) | 23.61 (24.04) | 20.93 (21.53) | 18.04 (21.60) | 0.023 |
| REM latency, min | 147.86 (66.37) | 141.51 (59.24) | 150.22 (68.53) | 146.71 (67.62) | 0.300 |
| Obstructive AHI, events/h TST | 0.40 (0.34) | 0.40 (0.29) | 2.11 (1.03) | 14.87 (12.44) | <0.001† |
| SpO2 nadir,‡ % | 93.80 (2.35) | 92.72 (6.00) | 90.27 (5.00) | 82.65 (10.94) | <0.001† |
| Total arousal index, events/h TST | 8.56 (3.95) | 9.14 (5.77) | 10.78 (7.39) | 17.51 (11.24) | <0.001† |
| Asthma, % | 14.94 | 20.45 | 19.04 | 24.71 | 0.430 |
Definition of abbreviations: AHI = apnea–hypopnea index; BMI = body mass index; OSA = obstructive sleep apnea; SpO2 = oxygen saturation as measured by pulse oximetry; SWS = slow-wave sleep; TST = total sleep time.
*
AHI measured as number of events per hour of total sleep time.
†
Comparison is significant following Bonferroni’s correction.
‡
SpO2 nadir refers to lowest levels of arterial oxygen saturation in the blood.