Table 3.
Diurnal slope in cortisol secretion by BMI categories, adjusted for confounders and mediators
| Diurnal slope in cortisol (samples 1–6, excluding sample 2)
|
|||
|---|---|---|---|
| Model A: adjusted for age, grade, gender, waking time [Regr. Coeff. (se)] | Model B: model A + health and health behaviorsa [Regr. Coeff. (se)] | Model C: model B + psychosocial factorsb [Regr. Coeff. (se)] | |
| Average cortisol (log) | 3.01 (0.10) | −2.78 (0.09) | −2.787 (0.12) |
| Time (since awakening) | −0.17 (0.02) | −0.17 (0.02) | −0.16 (0.02) |
| Time squared | 0.002 (0.001) | 0.003 (0001) | 0.003 (0001) |
| Obesity categories | |||
| BMI | |||
| Underweight BMI | Ref. | Ref. | |
| Desired BMI | −0.11 (0.07) | −0.12 (0.07) | −0.10 (0.08) |
| Overweight | −0.17 (0.07) | −0.17 (0.07) | −0.15 (0.08) |
| Obese | −0.16 (0.07) | −0.17 (0.07) | −0.16 (0.08) |
| P for BMI categories | <0.01 | <0.01 | <0.01 |
| Interaction of time (linear term) × BMI | |||
| Underweight BMI | Ref. | Ref. | Ref. |
| Desired BMI | 0.01 (0.02) | 0.02 (0.02) | 0.02 (0.02) |
| Overweight | 0.01 (0.02) | 0.02 (0.02) | 0.01 (0.02) |
| Obese | <0.001 (0.02) | 0.006 (0.02) | 0.003 (0.02) |
| P for interaction term | <0.01 | <0.01 | <0.01 |
| Interaction of time (quadratic term) × BMI | |||
| Underweight BMI | Ref. | Ref. | Ref. |
| Desired BMI | −0.001 (0.001) | −0.001 (0.001) | −0.002 (0.001) |
| Overweight | −0.001 (0.001) | −0.001 (0.001) | −0.001 (0.001) |
| Obese | <0.001 (0.001) | <−0.001 (0.001) | <−0.001 (0.001) |
| 0.05 | 0.07 | 0.01 | |
Regr. Coeff., Regression coefficient.
a
Alcohol consumption, smoking, poor self-rated health, short sleep, and fatigue.
b
Depression symptoms, financial insecurity, and stress on the day of sampling.