Table 1. Body composition of boys and girls at birth and 6-7 years of age. Data shown as mean±SD or median (IQR), unless otherwise stated.
| Neonate | 6-7 years | |||
|---|---|---|---|---|
| Boys | Girls | Boys | Girls | |
| N | 97 | 103 | 97 | 103 |
| Age (days for neonatal/years for childhood), median (range) | 8 (1-16) | 8 (1-15) | 7.10 (6.41-7.65) | 7.08 (6.36-7.69) |
| Height / Length at birth (cm) | 50.7 (48.6-52.1) | 49.7 (48.6-50.8)a | 122.9±5.9 | 122.6±5.6 |
| Weight (kg) | 3.51±0.54 | 3.52±0.49 | 23.5 (20.9-26.0) | 23.8 (20.6-27.0) |
| Lean mass (kg) | 3.00±0.42 | 2.91±0.35 | 17.11±2.21 | 16.10±2.24b |
| Fat mass (kg) | 0.46 (0.33-0.61) | 0.55 (0.41-0.72)b | 5.44 (4.23-6.79) | 7.04 (5.18-8.58)c |
| Tibial pQCT | ||||
| 4% Total Area (mm2) | 695 (567-753) | 669 (592-758) | ||
| 4% Trabecular vBMD (mg/cm3) | 303±55 | 308±54 | ||
| 38% Total Area (mm2) | 221 (200-251) | 228 (199-256) | ||
| 38% Cortical Area (mm2) | 124 (115-139) | 120 (111-136) | ||
| 38% Cortical vBMD (mg/cm3) | 1036±33 | 1030±37 | ||
| Strength Strain Index | 484±96 | 453±105 | ||
a
p<0.05
b
p<0.01
c
p<0.001 compared to boys of same age.