Vuosien 2007–2012 välillä on julkaistu 3 systemaattista kirjallisuuskatsausta (systematic literature review, SLR) «Cranney A, Horsley T, O'Donnell S ym. Effectivenes...»1, «Chung M, Balk EM, Brendel M ym. Vitamin D and calc...»2, «Viljakainen HT, Natri AM, Kärkkäinen M ym. A posit...»3 aiheesta D-vitamiini ja luusto lapsilla ja nuorilla. Näitä on arvioitu systemaattisessa katsauksessa «Lamberg-Allardt C, Brustad M, Meyer HE ym. Vitamin...»6. Alla oleva teksti perustuu siihen.
Cranney et al (2007) «Cranney A, Horsley T, O'Donnell S ym. Effectivenes...»1 addressed the question whether specific concentrations of S-25(OH)D were associated with bone health outcomes in infants, older children and adolescents. Chung et al (2009) «Chung M, Balk EM, Brendel M ym. Vitamin D and calc...»2 builds on Cranney et al. (2007) «Cranney A, Horsley T, O'Donnell S ym. Effectivenes...»1, but did not find any new studies and thus build their conclusion on Cranney et al. (2007) «Cranney A, Horsley T, O'Donnell S ym. Effectivenes...»1.
Cranney et al. (2007) «Cranney A, Horsley T, O'Donnell S ym. Effectivenes...»1 found 3 RCT (n ranging from 18-80 infants) and 4 case-control studies (n ranging from 21-82 infants). The interventions were 400 IU vs. placebo (2 studies), 1000IU vrs. 500 IU (1 study). All studies used vitamin D2. They concluded that the evidence for an association between specific concentrations of 25OHD and BMC in infants is inconsistent. There was f air evidence for an inverse relation between 25OHD and PTH at low levels of 25OHD. A threshold may exist around 27 nmol/l.
Older children and adolescents
Cranney et al. (2007) «Cranney A, Horsley T, O'Donnell S ym. Effectivenes...»1 include 3 studies in older children (1 RCT, 1 cohort and 1 before and after study) and 4 studies in adolescents (1 RCT, 2 Cohort and 1 cases-control study). One of the studies did not assess BMC/BMD but only PTH The doses in the RCTs were 400 IU/day or 14000/week.
They concluded that there was fair evidence for S-25(OH)D being associated with change in BMD/BMC. However, results from two RCTs did not consistently confirm that vitamin D supplementation had an effect. Moreover, they referred to a Finnish RCT (Viljakainen et al 2006 «Viljakainen HT, Natri AM, Kärkkäinen M ym. A posit...»3) in 228 adolescent girls published after they had done their systematic search. The intervention was two doses of vitamin D3 (200 and 400 IU daily) compared to placebo. In per protocol analyses, they reported positive effects on BMC (mean S-25(OH)D > 50 nmol/L achieved in the intervention groups), whereas the results were not statistically significant in the intention to treat analysis.
Winzenberg et al. (2010) «Winzenberg TM, Powell S, Shaw KA ym. Vitamin D sup...»4, «»1 including data up to autumn 2009 (six RCTs, 541 subjects receiving vitamin D and 343 placebo), the objective was to ‘determine the effectiveness of vitamin D supplementation for improving bone mineral density in children’. The dose administered ranged from 3.3 daily to 350 µg per week. Overall they did not find any statistically significant effect of vitamin D supplementation on total body BMC, hip BMD or forearm BMD, whereas a small effect on lumbar BMD was suggested. No statistically significant difference was found between studies using high or low dose of vitamin D. The difference in effects between studies with high and low baseline s-25(OH)D studies was not statistically significant (total body BMC, p = 0.09 for difference), although in studies with participants with low S-25(OH)D (≤ 35 nmol/l), a significant effect o of supplementation was found for total body BMC and lumbar BMD.
They concluded that “These results do not support vitamin D supplementation to improve bone density in healthy children with normal vitamin D levels, but suggest that supplementation of deficient children may be clinically useful. Further RCTs in deficient children are needed to confirm this”.
Mølgaard et al. «Mølgaard C, Larnkjaer A, Cashman KD ym. Does vitam...»5 (2109 with rating A. In this double-blinded RCT, 221 Danish girls aged 10-11 years were randomized to take vitamin D3 (5µg or 10µg) or placebo over one year. Overall the intervention had no effect on BMC or BMD (total body and lumbar spine). Compared to the somewhat similar study by Viljakainen et al 2006 «Viljakainen HT, Natri AM, Kärkkäinen M ym. A posit...»3 which only included girls from September to March (and which found an effect in the compliance controlled analysis), the current study included girls throughout the year.