Table 1.
Sample Characteristics Overall and by Mean Sleep Duration Categories
| Subject Characteristics | All Subjects (n=471) | Mean Sleep Duration Categories |
||
|---|---|---|---|---|
| Shorter ≤6.5 hrs (n=61) | Intermediate 6.6 – 8.74 hrs (n=338) | Longer ≥ 8.75 hrs (n=72) | ||
| Age | 15.7 ± 2.1 | 16.1 ± 2.0 | 15.6 ± 2.1 | 15.8 ± 2.2 |
| Male Sex | 232 (49.3%) | 32 (52.5%) | 171 (50.6%) | 29 (40.3%) |
| Minority race | 201 (42.7%) | 36 (59.0%) | 137 (40.5%) | 28 (38.9%) |
| Preterm | 232 (49.3%) | 30 (49.2%) | 164 (48.5%) | 38 (52.8%) |
| Moderate/ vigorous daily activity | ||||
| < 30 min | 223 (47.3%) | 30 (49.2%) | 155 (45.9%) | 38 (52.8%) |
| 30 to 59 min | 81 (17.2%) | 9 (14.7%) | 60 (17.7%) | 12 (16.7%) |
| ≥ 60 min | 167 (35.5%) | 22 (36.1%) | 123 (36.4%) | 22 (30.5%) |
| Extended weekend sleep duration | ||||
| No | 347 (73.2%) | 26 (42.6%) | 252 (74.6%) | 67 (93.1%) |
| Yes | 70 (14.9%) | 23 (37.7%) | 47 (13.9%) | 0 (0%) |
| Unknown | 56 (11.9%) | 12 (19.7%) | 39 (11.5%) | 5 (6.9%) |
| Adiposity | ||||
| Waist Circumference (cm) | 74.8 ± 11.8 | 76.5 ± 12.9 | 74.7 ± 11.5 | 73.4 ± 12.0 |
| Obesity (BMI ≥30 or BMI ≥ 95th percentile) | 88 (18.7%) | 13 (21.3%) | 64 (18.9%) | 11 (15.3%) |
| BMI percentile | 70.4 (45.7, 92.1) | 74.4 (42.7, 89.8) | 68.7 (46.4, 92.4) | 66.9 (36.0, 90.5) |
| Insulin & Glucose | ||||
| HOMA | 1.95 (1.37, 2.82) | 1.96 (1.30, 3.29) | 1.95 (1.37, 2.71) | 1.99 (1.43, 2.89) |
| Fasting Insulin (uIU/mL) | 8.9 (6.6, 12.7) | 8.7 (6.3, 13.9) | 8.9 (6.6, 12.3) | 9.1 (6.8, 12.8) |
| Fasting Glucose (mg/dL) | 88.0 ± 7.7 | 87.9 ± 7.1 | 88.1 ± 7.6 | 88.0 ± 8.7 |
| G:I Ratio * | 9.9 (6.9, 13.2) | 9.6 (6.1, 13.4) | 9.9 (7.0, 13.2) | 9.9 (6.8, 13.0) |
| G:I Ratio < 7 | 122 (25.9%) | 17 (27.9%) | 84 (24.9%) | 21 (29.2%) |
N=471 observations on n=387 people; N (column %) shown for categorical variables; median (IQR) or mean ± SD presented for continuous variables
*
G:I ratio = fasting glucose / fasting insulin