The Assessment of ۲۵-Hydroxy Vitamin D Serum Level in Asthmatic Patients: A Case-Control Study

Background: The prevalence of vitamin D deficiency is increasing due to changes in lifestyle and dietary habits. The aim of this study was to compare the serum levels of ۲۵-hydroxy vitamin D between patients with bronchial asthma and the healthy control group. Patients and Methods: In this case-control study, ۴۵ patients with asthma and ۴۵ healthy subjects were enrolled and the level of serum ۲۵ (OH) vitamin D was measured in both groups. In addition, a welltrained observer assessed airway reversibility, peak flowmetry and spirometry in the participants. The data were statistically analyzed using t test, one-way analysis of variance (ANOVA), and chi-square test with Stata software (version ۱۱). Results: The mean age (±SD) of participants were ۴۹.۰۶ ±۱۶.۴۳ and ۴۶.۱۳ ±۱۶.۱۰ years in case and control groups, respectively (P=.۳۹۴). The prevalence of vitamin D deficiency was high in both groups (۶۹% in case and ۶۵.۵% in control groups). The mean (±SD) serum ۲۵ (OH) vitamin D was ۱۶.۲۴ (±۱۴.۹۸) ng/ml in case group and ۱۷.۷۰ (±۱۶.۰۷) ng/mL in control group (P=.۶۵۷). We found a positive correlation between the levels of vitamin D and the amount of FEV۱ (r=۰.۲). Conclusions: According to the present study, the mean serum levels of vitamin D differences were not statistically significant between asthmatic patients and control group. However, the results of this study showed a positive relationship between forced expiratory volumes in first second (FEV۱) and vitamin D levels