The Relationship Between Serum 25 Hydroxy Vitamin D Levels and Asthma in Children

Abstract

PurposeAsthma and other allergic disorders have increased over the past decades in nearly all nations. Many studies have suggested the role of vitamin D deficiency in both T-helper1 and T-helper2 diseases; however, the association between vitamin D, allergy, and asthma remains uncertain. In this study, the associations of 25-hydroxy vitamin D3 levels with asthma and with the severity of asthma were evaluated.MethodsThis cross-sectional study was conducted on 50 asthmatic children and 50 healthy controls aged 6-18 years. Serum 25-hydroxy vitamin D3 levels were determined and compared between the two groups. The relationship between serum vitamin D levels and pulmonary function test outcomes and eosinophil counts were examined in asthmatic patients.ResultsUnivariate analysis of the relationship between asthma and vitamin D showed that decreased vitamin D levels were associated with significantly increased odds of asthmatic state (P=0.002). In a multivariate analysis after adjustment for age, body mass index, and sex, the relationship between vitamin D and asthma increased. In asthmatic patients, 25-hydroxy vitamin D levels had direct and significant correlations with both predicted FEV1 (R2=0.318; P=0.024) and FEV1/FVC (R2=0.315; P=0.026). There were no associations between vitamin D level and eosinophil counts, duration of disease, and the number of hospitalization or unscheduled visits in the previous year (P>0.05).ConclusionsThese results showed that serum 25-hydroxy vitamin D levels were inversely associated with asthma, and there was a direct and significant relationship between vitamin D levels and pulmonary function test outcomes in asthmatic children. An interventional study in asthmatic patients with low serum vitamin D concentration may establish a causal relationship between asthma and vitamin D.

Serum 25-hydroxyvitamin D levels do not correlate with asthma severity in a case-controlled study of children and adolescents

“…A similar case control study involving 50 asthmatic children and 50 controls found a significant difference in 25(OH)D levels and also a significant inverse correlation with asthma severity (15) . However, another study (20) , powered to detect an 18 % difference in total 25(OH)D levels failed to detect either a significant difference in 25(OH)D levels or a correlation with asthma severity in a similar case-control study in 80 asthmatic adults and 80 controls.…”

“…Another study from northern Italy showed a direct correlation between asthma control and serum 25(OH)D in a cohort of asthmatic children (14) . Other cross-sectional studies in children have shown that serum 25(OH)D concentrations are directly correlated with pulmonary function parameters, such as forced expiratory volume in one second (15) , and also inversely correlated with asthma severity and airway smooth muscle mass (16) .…”

Effects of Vitamin D Levels on Asthma Control and Severity in Children

“…D vitamininin aynı zamanda astım şiddeti ve düşük steroid yanıtıyla ilişkili olan Th17 sitokinlerin üretimini de inhibe ettiği gösterilmiştir. D vitamini ayrıca steroid dirençli astımda glukokortikoide olan yanıtı ters çevirebilir (6,9,31). D vitamini eksikliğinin kortikosteroidlere yanıtın azalmasına neden olması astım ataklarına katkıda bulunabilir.…”

Vitamin D with asthma and COPD: not a false hope? A systematic review and meta-analysis

“…We included studies with data on the study group of asthma and COPD and in a control group of non-asthmatics and non-COPD: 7 studies were in children (Brehm et al, 2010;Freishtat et al, 2010;Rothers et al, 2011;Alyasin et al, 2011;Bener et al, 2012;Brehm et al, 2012;Goleva et al, 2012); 3 studies were with adults (Li et al, 2011;Persson et al, 2012;Zhou et al, 2012); 2 studies were on COPD (Persson et al, 2012;Zhou et al, 2012), and 8 studies on asthma. Studies without a control group were excluded.…”