Vitamin D and Health

pregnancy (n=2) or cord blood 25(OH)D concentration (n=2) and asthma, reported conflicting results
(Harvey et al., 2014) . The authors highlighted that substantial heterogeneity in study design,
outcome and exposure definition and the conflicting results made it difficult to conclude any definitive
relationship between maternal serum 25(OH)D concentration and development of asthma in the
offspring.
6.257 Tolppanen et al. (2013) examined prospective associations between serum 25(OH)D 2 and 25(OH)D 3
concentration measured in children aged 9.8y and incidence of wheezing (n=3323; 141 cases), asthma
(n=3323, 464 cases) and flexural dermatitis (n=3748; 300 cases). Serum 25(OH)D 2 concentration was
inversely associated with wheezing (OR per doubling of exposure=0.83, 95% CI, 0.68–1.00) and
flexural dermatitis (OR=0.83; 95% CI, 0.72–0.94) and serum 25(OH)D 3 concentration was positively
associated with wheezing (OR=1.14; 95% CI, 1.03–1.28) and flexural dermatitis (OR=1.09; 95% CI,
1.00–1.18).
6.258 A nested case control study (Mai et al., 2012) found no association between baseline serum 25(OH)D
concentration < 50 nmol/L and asthma in men (OR=1.47; 95% CI, 0.93-2.32) or women (OR=0.94; 95%
CI, 0.67-1.32).
6.259 A prospective study in Australia (Hollams et al., 2011) reported that serum 25(OH)D concentration in
children at age 6 y (n=989) was inversely associated with the risk of developing atopy (OR=0.14; 95%
CI, 0.04-0.47) and asthma (OR=0.11; 95% CI, 0.02-0.84) at age 14 y (n=689).
6.260 Chawes et al. (2014) investigated the relationship between cord serum 25(OH)D concentration and
development of asthma and allergy-related conditions in early childhood (n=257). Children were
followed until the age of 7y and were monitored for troublesome lung symptoms (TROLS), asthma,
respiratory infections, allergic rhinitis and eczema. After adjustment for season of birth, cord serum
25(OH)D concentration < 50 nmol/L was associated with a significant increase in risk of recurrent
TROLS (HR=2.65; 95% CI, 1.02-6.86). No association was found with respiratory infections or asthma,
lung function, rhinitis or eczema.
Atopic Disorders
Intervention studies
6.261 No intervention studies could be identified.
Cohort studies
6.262 A systematic review by Harvey et al. (2014) examined the relationship between serum 25(OH)D
concentration in pregnancy and atopy risk in offspring. Out of 2 studies which conducted skin prick
tests as a measure of atopic sensitisation, one showed no effect of maternal serum 25(OH)D
concentration on atopic sensitisation to potential allergens at 5y of age (Devereux et al., 2007) while
the other showed a greater risk of a positive response to a number of allergens when cord plasma
25(OH)D concentration was ≥ 100 nmol/L compared to concentrations between 50-74.9 nmol/L
(Rothers et al., 2011). This study also demonstrated a non-linear relationship between cord plasma
25(OH)D concentration and total and allergen-specific IgE for 6 allergens, with the highest IgE
concentrations in children with cord plasma 25(OH)D concentration < 50 nmol/L and ≥ 100 nmol/L.
6.263 Jones et al. (2012) prospectively examined the association between vitamin D exposure in utero and
allergic outcomes in the first year of life in mother-infant pairs (n=231). Cord blood 25(OH)D
concentration was significantly lower in infants who developed eczema by 12 months of age (p=0.18).
Risk of eczema was significantly reduced with increasing cord blood 25(OH)D concentration: a
83