Baseline characteristics of participants in the ViDAS trial (N = 62)
| Characteristics . | Vitamin D3 100 000 IU/mo (n = 31) . | Vitamin D3 12 000 IU/mo (n = 31) . | P* . |
|---|---|---|---|
| Age, mean ± SD, y | 9.9 ± 4.0 | 9.9 ± 3.8 | 0.98 |
| Female, n (%) | 16 (52) | 16 (52) | 1.00 |
| Sickle cell type, n (%) | 0.84 | ||
| SS | 26 (84) | 28 (90) | |
| SC | 3 (10) | 2 (6) | |
| Sβ0 thalassemia | 1 (3) | 1 (3) | |
| Sβ+ thalassemia | 1 (3) | 0 (0) | |
| Hydroxyurea, n (%) | 18 (58) | 17 (55) | 1.00 |
| History of ACS, n (%) | 9 (29) | 10 (32) | 1.00 |
| History of asthma, n (%) | 14 (45) | 13 (42) | 1.00 |
| Oxygen saturation, mean ± SD, % | 98.9 ± 1.5 | 98.7 ± 1.4 | 0.57 |
| 25-Hydroxyvitamin D, mean ± SD, ng/mL | 15.0 ± 7.0 | 13.6 ± 6.2 | 0.48 |
| Dietary vitamin D, mean ± SD, IU/d | 166.1 ± 124.2 | 228.6 ± 162.5 | 0.10 |
| Dietary calcium, mean ± SD, mg/d | 838.2 ± 522.4 | 941.9 ± 617.3 | 0.49 |
| Sun exposure, mean ± SD, h/wk | 9.1 ± 8.7 | 8.6 ± 6.0 | 0.99 |
| Baseline respiratory events, mean ± SD | |||
| Duration, d | 419 ± 202.2 | 470.8 ± 161.2 | 0.28 |
| Number, per patient | 4.9 ± 3.3 | 4.7 ± 3.2 | 0.88 |
| Annualized number | 4.3 ± 2.2 | 3.9 ± 2.3 | 0.47 |
| Interevent interval, d | 74.7 ± 52.9 | 108.6 ± 96.2 | 0.10 |
| Pulmonary function test, mean ± SD† | (n = 28) | (n = 30) | |
| FVC, % predicted | 85.5 ± 14.7 | 90.2 ± 12.7 | 0.19 |
| FEV1, % predicted | 80.4 ± 12.5 | 84.9 ± 12.6 | 0.18 |
| FEV1/FVC ratio, % | 84.0 ± 7.8 | 83.3 ± 8.4 | 0.75 |
| FEF25-75, % predicted | 69.8 ± 26.0 | 68.8 ± 24.6 | 0.90 |
| RV/TLC ratio, % | 26.9 ± 6.4 | 25.1 ± 7.2 | 0.38 |
| DLCO, % predicted | 68.0 ± 14.5 | 72.3 ± 16.8 | 0.40 |
| FENO, ppb | 19.3 ± 14.3 | 16.9 ± 11.6 | 0.50 |
| MIP, cm H2O | 69.1 ± 27.0 | 59.9 ± 23.0 | 0.25 |
| MEP, cm H2O | 66.3 ± 18.6 | 66.3 ± 23.7 | 1.00 |
| Hand-grip strength, mean ± SD, pounds force‡ | n = 25 | n = 27 | |
| Right hand | 21.1 ± 16.2 | 16.9 ± 11.5 | 0.28 |
| Left hand | 19.9 ± 16.8 | 16.0 ± 11.1 | 0.34 |
| Dominant hand | 21.2 ± 16.2 | 17.1 ± 11.3 | 0.30 |
| Characteristics . | Vitamin D3 100 000 IU/mo (n = 31) . | Vitamin D3 12 000 IU/mo (n = 31) . | P* . |
|---|---|---|---|
| Age, mean ± SD, y | 9.9 ± 4.0 | 9.9 ± 3.8 | 0.98 |
| Female, n (%) | 16 (52) | 16 (52) | 1.00 |
| Sickle cell type, n (%) | 0.84 | ||
| SS | 26 (84) | 28 (90) | |
| SC | 3 (10) | 2 (6) | |
| Sβ0 thalassemia | 1 (3) | 1 (3) | |
| Sβ+ thalassemia | 1 (3) | 0 (0) | |
| Hydroxyurea, n (%) | 18 (58) | 17 (55) | 1.00 |
| History of ACS, n (%) | 9 (29) | 10 (32) | 1.00 |
| History of asthma, n (%) | 14 (45) | 13 (42) | 1.00 |
| Oxygen saturation, mean ± SD, % | 98.9 ± 1.5 | 98.7 ± 1.4 | 0.57 |
| 25-Hydroxyvitamin D, mean ± SD, ng/mL | 15.0 ± 7.0 | 13.6 ± 6.2 | 0.48 |
| Dietary vitamin D, mean ± SD, IU/d | 166.1 ± 124.2 | 228.6 ± 162.5 | 0.10 |
| Dietary calcium, mean ± SD, mg/d | 838.2 ± 522.4 | 941.9 ± 617.3 | 0.49 |
| Sun exposure, mean ± SD, h/wk | 9.1 ± 8.7 | 8.6 ± 6.0 | 0.99 |
| Baseline respiratory events, mean ± SD | |||
| Duration, d | 419 ± 202.2 | 470.8 ± 161.2 | 0.28 |
| Number, per patient | 4.9 ± 3.3 | 4.7 ± 3.2 | 0.88 |
| Annualized number | 4.3 ± 2.2 | 3.9 ± 2.3 | 0.47 |
| Interevent interval, d | 74.7 ± 52.9 | 108.6 ± 96.2 | 0.10 |
| Pulmonary function test, mean ± SD† | (n = 28) | (n = 30) | |
| FVC, % predicted | 85.5 ± 14.7 | 90.2 ± 12.7 | 0.19 |
| FEV1, % predicted | 80.4 ± 12.5 | 84.9 ± 12.6 | 0.18 |
| FEV1/FVC ratio, % | 84.0 ± 7.8 | 83.3 ± 8.4 | 0.75 |
| FEF25-75, % predicted | 69.8 ± 26.0 | 68.8 ± 24.6 | 0.90 |
| RV/TLC ratio, % | 26.9 ± 6.4 | 25.1 ± 7.2 | 0.38 |
| DLCO, % predicted | 68.0 ± 14.5 | 72.3 ± 16.8 | 0.40 |
| FENO, ppb | 19.3 ± 14.3 | 16.9 ± 11.6 | 0.50 |
| MIP, cm H2O | 69.1 ± 27.0 | 59.9 ± 23.0 | 0.25 |
| MEP, cm H2O | 66.3 ± 18.6 | 66.3 ± 23.7 | 1.00 |
| Hand-grip strength, mean ± SD, pounds force‡ | n = 25 | n = 27 | |
| Right hand | 21.1 ± 16.2 | 16.9 ± 11.5 | 0.28 |
| Left hand | 19.9 ± 16.8 | 16.0 ± 11.1 | 0.34 |
| Dominant hand | 21.2 ± 16.2 | 17.1 ± 11.3 | 0.30 |
DLCO, diffusing capacity of the lung for CO; FEF25-75, forced expiratory flow at 25%-75% vital capacity; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; MEP, maximum expiratory pressure; MIP, maximum inspiratory pressure; RV, residual lung volume; TLC, total lung capacity.
Baseline group differences were assessed by independent Student t test for continuous variables and by Fisher’s exact test for categorical variables.
Performed only by participants ages ≥5 years.
Performed only by participants ages ≥6 years.