Vitamin D and phenotypes of bronchial asthma

BackgroundMany studies have suggested the role of vitamin D deficiency in both T-helper1 and T-helper2 diseases. The existence of associations of vitamin D with asthma and allergy remains uncertain. While some suggest that vitamin D may be protective, others suggest that vitamin D supplementation may increase the risk of allergy.Aim of the workThe aim of the study was to evaluate the state of vitamin D in asthmatic patients and its potential relationship with asthma phenotypes.Patients and methodsThis study was conducted on 66 nonsmoker asthmatic patients and 30 healthy controls. Serum 25-hydroxy vitamin D3 levels were determined and compared between the two groups. The relationship between serum vitamin D levels and asthma phenotypes were examined.ResultsVitamin D level was significantly lower in asthmatic patients than in control group, in asthmatic patients, vitamin D levels had a significant positive correlation with FEV1% predicted and a significant negative correlation with body mass index, the number of atopic patients was significantly higher in bronchial asthma patients with vitamin D insufficiency than those with sufficient vitamin D.ConclusionVitamin D deficiency was highly prevalent in asthmatic patients and it was associated with atopy and asthma severity.