Serum Vitamin D Levels Amongst Asthmatic and Non-Asthmatic Children in Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria: A Comparative Cross-Sectional Study

Abstract

Background: Asthma is a common chronic inflammatory disease of the airways. Recent studies have found an additional important role of Vitamin D (VD) in extra-skeletal health, particularly in the aetio - pathogenesis of childhood asthma due its effects in immune modulation and inflammation systems. 

Aim and objective: This study was aimed to determine and compare the serum VD amongst asthmatic and non-asthmatic children, and also to determine the relationship between serum VD level and lung function test (LFT) in asthmatic children in Usmanu Danfodiyo University Teaching Hospital (UDUTH), Sokoto. 

Materials and methods: This was a comparative cross-sectional study. A total of 120 children were enrolled (60 asthmatic and 60 non-asthmatic) over a period of 4 months. Serum VD was assayed with ELISA kit, portable spirometer was used to assess the LFT of the participants. Data was analysed using SPSS version 21.0. 

Results: The median serum VD levels among asthmatic children was 16.25ng/mL and that of non-asthmatic children was 16.80ng/mL with no significant difference in their median VD levels (p = 0.550). Significant difference in the median FEV1/FVC among asthmatic and non-asthmatic was found (p = 0.001). No relationship was found between serum VD and LFT (FEV₁: r =0.034, p = 0.080, FEV1/FVC: r=0.067, p=0.623, PEFR: r = 0.045, p= 0.152).

Conclusion: Vitamin D deficiency was highly prevalent (76%) among study participants. No significant difference was found between the median serum VD levels of the asthmatic and non-asthmatic children and no relationship was found between serum VD and LFT of asthmatic children. However, there was difference in the LFT between asthmatic and non- asthmatic subjects. Emphasis should made in routine serum VD screening and improve serum VD status among study population through health education, dietary supplementation and fortification.