Association between vitamin D status and asthma control: A meta-analysis of randomized trials

• Published in: Respiratory medicine 2019-04, Vol.150, p.85-94
• Main Authors: Wang, Mingming, Liu, Meicen, Wang, Cairu, Xiao, Yue, An, Tong, Zou, Meijuan, Cheng, Gang
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Asthma; Asthma - drug therapy; Asthma - metabolism; Asthma - physiopathology; Bias; Child; Child, Preschool; Clinical trials; Collaboration; Correlation analysis; Disease Progression; Evidence-based medicine; Exhalation; Female; Forced Expiratory Volume - drug effects; Humans; Infant; Interleukin 10; Interleukin-10 - analysis; Interleukins; Male; Meta-analysis; Middle Aged; Nitric oxide; Nitric Oxide - analysis; Patients; Pulmonary functions; Quality; Randomization; Randomized Controlled Trials as Topic; RCTs; Respiratory function; Respiratory Function Tests - methods; Software; Statistical analysis; Subgroups; Supplements; Symptom Assessment - methods; Symptom Assessment - statistics & numerical data; Treatment; Treatment Outcome; Vitamin D; Vitamin D - adverse effects; Vitamin D - therapeutic use; Vitamin D Deficiency - complications; Vitamin D Deficiency - drug therapy; Vitamin D Deficiency - epidemiology; Vitamins - adverse effects; Vitamins - therapeutic use
• ISSN: 0954-6111; 1532-3064
• DOI: 10.1016/j.rmed.2019.02.016

There is a controversy in terms of the efficacy of vitamin D supplementation in improving asthma symptom control. Moreover, whether there is a difference in the treatment effect with respect to baseline vitamin D status remains unknown. This meta-analysis was to assess the correlations of vitamin D status with asthma-related respiratory outcomes. PubMed, EMBASE, and Cochrane Library were searched for randomized controlled trials of vitamin D supplementation in patients with asthma. Primary outcomes were the rate of asthma exacerbation and predicted percentage of forced expiratory volume in first second (FEV1%). Secondary outcomes were asthma control test (ACT) scores, fractional exhaled nitric oxide (FeNO), interleukin-10 (IL-10) and adverse events. A total of 14 randomized controlled trials (1421 participants) fulfilled the inclusion. Vitamin D supplementation was associated with a significant reduction in the rate of asthma exacerbation by 27% (RR: 0.73 95%Cl (0.58–0.92)). In subgroup analysis, the protective effect of exacerbation was restricted in patients with vitamin D insufficiency (vitamin D