Table 2. Associations of Greater Evening Preferences and Social Jet Lag With Adiposity, Adjusted for Television Viewing, Diet Quality, and Physical Activity.
| Characteristic | Multivariable-Adjusted β (95% CI)a | |
|---|---|---|
| Girls | Boys | |
| Evening preferencesb | ||
| BMI z score | 0.04 (−0.01 to 0.08) | 0.00 (−0.05 to 0.05) |
| DXA, kg/m2 | ||
| Total fat mass index | 0.14 (−0.02 to 0.30) | 0.08 (−0.08 to 0.23) |
| Trunk fat mass index | 0.07 (−0.01 to 0.15) | 0.03 (−0.04 to 0.10) |
| Waist circumference, cm | 0.42 (−0.05 to 0.90) | 0.14 (−0.40 to 0.68) |
| Sum of skinfolds, cm | 0.64 (0.07 to 1.20) | 0.32 (−0.31 to 0.95) |
| Cardiometabolic risk score, z score | 0.01 (−0.02 to 0.05) | 0.00 (−0.04 to 0.03) |
| HDL cholesterol, mg/dL | −0.21 (−0.92 to 0.51) | −0.31 (−1.10 to 0.48) |
| Log HOMA-IR | 0.01 (−0.02 to 0.04) | 0.00 (−0.03 to 0.03) |
| Log triglycerides, mg/dL | 0.02 (0.00 to 0.05) | 0.01 (−0.02 to 0.03) |
| Systolic blood pressure, mm Hg | −0.08 (−0.52 to 0.36) | −0.36 (−0.75 to 0.03) |
| Social jet lagc | ||
| BMI z score | 0.08 (−0.03 to 0.19) | 0.06 (−0.05 to 0.17) |
| DXA, kg/m2 | ||
| Total fat mass index | 0.46 (0.08 to 0.84) | 0.10 (−0.27 to 0.46) |
| Trunk fat mass index | 0.24 (0.05 to 0.44) | 0.07 (−0.10 to 0.23) |
| Waist circumference, cm | 1.08 (−0.09 to 2.26) | 0.71 (−0.52 to 1.94) |
| Sum of skinfolds, cm | 1.29 (−0.08 to 2.67) | 0.24 (−1.20 to 1.68) |
| Cardiometabolic risk score, z score | 0.07 (−0.02 to 0.15) | 0.00 (−0.08 to 0.08) |
| HDL cholesterol, mg/dL | 0.57 (−1.28 to 2.43) | −0.23 (−2.04 to 1.58) |
| Log HOMA-IR | 0.02 (−0.05 to 0.10) | −0.04 (−0.12 to 0.04) |
| Log triglycerides, mg/dL | 0.01 (−0.05 to 0.07) | −0.01 (−0.07 to 0.05) |
| Systolic blood pressure, mm Hg | 0.77 (−0.31 to 1.84) | 0.27 (−0.62 to 1.17) |
Abbreviations: BMI, body mass index; DXA, dual-energy x-ray absorptiometry; HDL, high-density lipoprotein; HOMA-IR, homeostatic model assessment of insulin resistance.
Models adjust for adolescent age, race/ethnicity, pubertal status, season of measurement, parental socioeconomic status, actigraphy-measured sleep duration, parent report of adolescent physical activity, and adolescent report of television viewing and indicators of diet quality (intake of sugary drinks and fast food).
Reduced Morningness-Eveningness Scales for Children is derived from 5 questions regarding adolescents’ preferences for when to get into bed and out of bed, what time of day they had the most energy, and how easy it was to get up in the morning; in multivariable models, the scores were inverted such that higher scores indicate stronger evening preferences.
Social jet lag is the mean sleep midpoint on weekend days minus the mean sleep midpoint on weekdays.