Table 1.
Baseline characteristics of study subjectsa
| Characteristic | All subjects (n = 17) | Vitamin D2 group (n = 9) | Vitamin D3 group (n = 8) |
|---|---|---|---|
| Age (months) | 44.5 (28–118) | 44.5 (28–66) | 45.6 (32.5–118) |
| Sex (male/female) | 6/11 | 2/7 | 4/4 |
| Familial rickets | 8 (47%) | 4 (44%) | 4 (50%) |
| Daily sun exposure (h) | 3.25 (0.5–8) | 2.75 (1–8) | 3.5 (0.5–5) |
| Height-for-age z-score | −3.6 (−7.7 to −0.1) | −3.6 (−7.7 to −1.8) | −3.5 (−4.5 to −0.1) |
| Weight-for-height z-score | 0.3 (−1.0 to 1.6) | 0.3 (−1.0 to 1.6) | 0.2 (−0.9 to 0.8) |
| Weight-for-age z-score | −1.9 (−4.6 to −0.3) | −2.0 (−4.6 to −0.3) | −1.6 (−3.1 to −0.3) |
| Daily calcium intake (mg) | 172 (56–309) | 172 (56–261) | 186 (82–309) |
| Radiographic score | 2.75 (1.5–10) | 3.5 (1.5–10) | 2.25 (1.5–8) |
| Serum biochemistriesb | |||
| Calcium (mg/dl), reference range 9.6–10.6 | 8.8 ± 1.0 | 8.6 ± 1.1 | 9.0 ± 1.0 |
| Phosphorus (mg/dl), reference range 3.7–5.4 | 4.0 ± 1.1 | 3.6 ± 0.8 | 4.5 ± 1.3 |
| Albumin (g/dl), reference range 3.5–5.0 | 4.2 ± 0.4 | 4.2 ± 0.3 | 4.1 ± 0.5 |
| Alkaline phosphatase (U/liter), reference range 149–476 | 686 (182–2476) | 751 (182–2476) | 447 (205–1055) |
| 25-Hydroxyvitamin D (ng/ml), optimal range 25–80 | 20 (5–32) | 18 (10–32) | 23 (5–32) |
| 1,25-Dihydroxyvitamin D (pg/ml), reference range24–86 | 143 ± 76 | 156 ± 74 | 130 ± 82 |
a
Values for nonnormally distributed continuous variables are shown as medians with range in parentheses. Normally distributed variables are shown as means ± sd.
b
To convert values of serum calcium to millimoles per liter, multiply by 0.25; to convert values of serum phosphorus to millimoles per liter, multiply by 0.32; to convert values of albumin to grams per liter, multiply by 10; to convert values of 25-hydroxyvitamin D to nanomoles per liter, multiply by 2.5; to convert values of 1,25-dihydroxyvitamin D to picomoles per liter, multiply by 2.4. Pediatric reference ranges are provided for the age range of children in the study.