Vitamin D and asthma occurrence in children: A systematic review and meta-analysis

The Sun also rises

“…They also found that children who received vitamin D supplementation had fewer exacerbations than did those who received a placebo. 3 That finding is in keeping with those of other systematic reviews and meta-analyses, although such supplementation was not found to result in an improvement in lung function. 4 , 5 …”

“…In recent decades, there have been a number of studies evaluating vitamin D deficiency/insufficiency as a biomarker/risk factor in the prophylaxis and complementary treatment of asthma. 3 However, such studies, most of which were carried out in temperate countries with limited solar radiation throughout the year, have produced divergent results, as demonstrated in the conclusions of some systematic reviews and meta-analyses, such as one that included 36 studies evaluating serum vitamin D levels and complementary treatment of asthma with vitamin D versus placebo. 3 The authors of that systematic review and meta-analysis found that serum vitamin D levels were significantly lower among the children with asthma (n = 5,711) than among those without (n = 21,561).…”

“… 3 However, such studies, most of which were carried out in temperate countries with limited solar radiation throughout the year, have produced divergent results, as demonstrated in the conclusions of some systematic reviews and meta-analyses, such as one that included 36 studies evaluating serum vitamin D levels and complementary treatment of asthma with vitamin D versus placebo. 3 The authors of that systematic review and meta-analysis found that serum vitamin D levels were significantly lower among the children with asthma (n = 5,711) than among those without (n = 21,561). They also found that children who received vitamin D supplementation had fewer exacerbations than did those who received a placebo.…”

“…That could be attributed to several factors, including the serum vitamin D level at baseline, dose of vitamin D prescribed, and duration of supplementation; the age of the patients in the sample; latitude; sample variability; bias risk and control; follow-up time; and the use of medications, including oral corticosteroids, which are responsible for reducing serum vitamin D levels. 3 - 5 Another critical variable is inherent to the metabolism of vitamin D. It is known that vitamin D has a prolonged half-life and that daily supplementation for at least three months is necessary in order to reach a stable serum level. Therefore, different administration strategies and definitions of serum levels can generate different results.…”

“…In fact, a lack of asthma control is most often associated with failure to use or the inappropriate use of inhaled corticosteroids or other asthma medications, nonpharmacological measures, or comorbidity management. In the absence of a clinical response to such measures in children with low serum vitamin D levels, supplementation should be considered, 3 together with careful, systematic exposure to sunlight. 9 …”