Correlation of vitamin D receptor genotypes, specific IgE levels and other variables with asthma control in children

Abstract

Introduction Asthma is a common condition affecting millions of children globally. The main goal of this study is to assess factors related to asthma management, particularly atopy level and the impact of genetic variants of the vitamin D receptor (VDR) gene. Methods Asthmatic children were enrolled in an outpatient respiratory clinic. Information on patients’ medication adherence, medical and medication factors, and sociodemographic were gathered. Spirometry FEV1% and FVC% measurements, and the asthma control test were used to evaluate the severity of asthma, and genotyping of the VDR gene and radioallergosorbent test (RAST) were conducted. Regression analyses were conducted to evaluate variables associated with asthma control and spirometry measures. Results A total of 313 participants (67.4% males) were recruited in the current study. The mean age was 9.37 (±3.45) years. The mean score for adherence was 4.26 (±2.52), and only 46% of the participants had controlled asthma. Forward conditional stepwise binary regression showed that low and moderate Inhaled corticosteroids (ICS) dose (OR= 0.42 (95% CI 0.20–0.90), p = 0.026; OR = 0.371 (95% CI 0.2–0.72), p = 0.003, respectively) decreased the odds of being in the controlled asthma group, while higher inhaler score (OR = 2.75 (95% CI 2.17–3.49, p < 0.001)) increased the odds of being in the controlled asthma group. However, results found no association between VDR genotype and asthma control, spirometry values or hospitalization due to asthma. Conclusions The results indicated that many of the asthma patients had poorly controlled asthma. Factors that were associated with poor asthma control included poor inhaler technique.