Background: Asthma is heterogeneous disease usually characterized by a chronic airway inflammation; it is defined by the history of respiratory symptoms such as wheeze, shortness of breath, chest tightness and cough that vary over time and intensity together with variable expiratory air way limitation.
Objective: To assess the level of serum vitamin D and its effect on IL-10 production in patients with bronchial asthma and the effect of vitamin D supplementation for controlling of bronchial asthma and improving symptoms.
Subjects and Methods: This study was conducted on 50 subjects; 28 males and 22 females with mean ages 46.7 ± 14.4 years. All subjects of the study were selected from the outpatient clinic and chest Department, MostafaKamelMilitaryHospital over the period through March 2021 to June 2021. The subjects were divided into two groups: Group 1A (n = 20): Were subjected to pulmonary function test & had bronchial asthma symptoms (Studied during attacks); and had vitamin D supplementation; Group 1B (n = 20): Were subjected to pulmonary function test & & had bronchial asthma symptoms (Studied in-between the attacks attacks); and had vitamin D supplementation and Group 2 (n = 10): Were subjected to pulmonary function test & were apparently healthy (Control group); and had vitamin D supplementation; serum vitamin D (25 hydroxycholecalciferol), were measured by radioimmunoassay's before and after 12 weeks of vitamin D supplementation.
Results: Serum levels of vitamin D, IL-10 and FEV1 were significantly lower in asthmatic patients than in controls and in asthmatic patients during attack than those in between attack; there was highly statistically significant difference between vitamin D (Before and after vitamin D supplementation) in both studied patients; there was a statistically significant difference between FEV1 (Before and after vitamin D supplementation) in both studied patients; there was a statistically significant difference between IL-10 (Before and after vitamin D supplementation) in both studied patients and there was highly statistical positive correlation between (Vitamin D, IL-10 & FEV1) in studied patients before and after vitamin D supplementation.
Conclusion: There was a strong inverse relationship between serum vitamin D and pulmonary functions. Vitamin D deficiency occurred in the majority of bronchial asthma patients and therefore a decreased serum vitamin D level was considered an additional risk factor for respirator functions and bronchial asthma exacerbation, vitamin D supplementations increased levels of IL-10, which is essential for controls of inflammatory states associated with lung inflammatory disorders, such as asthma and interstitial lung disease.