TABLE 4.
Regression Modeling With Covariates Including Diagnostic Category, Bone Age, BMI z Score, Lean Mass, Activity Score, and IGF-I Levels
| Parameter Estimate | P | Variability Explained, % | |
|---|---|---|---|
| Lumbar BMD | |||
| Lean body mass | 8.33 × 10–3 | .002 | 42.2 |
| Bone age | 0.024 | .004 | |
| Diagnostic category (athletes with amenorrhea vs athletes with eumenorrhea and control subjects) | –0.037 | .004 | |
| Lumbar BMD z score | |||
| Lean body mass | 6.84 × 10–2 | .004 | 26.2 |
| Diagnostic category (athletes with amenorrhea vs athletes with eumenorrhea and control subjects) | –0.245 | .02 | |
| Lumbar BMAD | |||
| BMI z score | 0.008 | .01 | 27.5 |
| Bone age | 0.003 | .03 | |
| IGF-I level | 2.00 × 10–5 | .04 | |
| Lumbar BMAD z score | |||
| BMI z score | 0.595 | .002 | 24.4 |
| IGF-I level | 9.26 × 10–4 | .09 | |
| Hip BMD | |||
| Lean body mass | 9.57 × 10–3 | .001 | 32.5 |
| Diagnostic category (athletes with amenorrhea and control subjects vs athletes with eumenorrhea) | –0.034 | .01 | |
| Hip BMD z score | |||
| Lean body mass | 7.67 × 10–2 | .001 | 30.0 |
| Diagnostic category (athletes with amenorrhea and control subjects vs athletes with eumenorrhea) | –0.237 | .03 | |
| WB BMD | |||
| Lean body mass | 6.72 × 10–3 | .001 | 42.8 |
| Diagnostic category (athletes with amenorrhea vs athletes with eumenorrhea and control subjects) | –0.027 | .005 | |
| Bone age | 0.165 | .007 | |
| WB BMD z score | |||
| Lean body mass | 8.12 × 10–2 | .0007 | 29.7 |
| Diagnostic category (athletes with amenorrhea vs athletes with eumenorrhea and control subjects) | –0.227 | .04 | |
| WB BMC/height | |||
| Lean body mass | 0.149 | .0001 | 54.5 |
| Diagnostic category (athletes with amenorrhea vs athletes with eumenorrhea and control subjects) | –0.503 | .0007 | |
| Bone age | 0.250 | .009 | |
| WB BMC/height z score | |||
| Lean body mass | 5.95 × 10–2 | .0001 | 35.7 |
| Diagnostic category (athletes with amenorrhea vs athletes with eumenorrhea and control subjects) | –0.153 | .03 |