Vitamin D Supplementation in Asthma and Urticaria
Vitamin D has been shown to play a central immunomodulatory role in several conditions, including asthma and chronic urticaria, both of which involve disrupted immune and inflammatory responses.7,8
To examine the role of Vitamin D supplementation in childhood asthma, a recent meta-analysis7 of eight randomized controlled trials involving 573 children aged 3–18 years found a reduced risk of asthma exacerbations in children receiving Vitamin D supplementation, but no significant effect for asthma symptom scores and lung function. According to the authors, the trials had a “high degree of clinical diversity…and methodological heterogeneity” and therefore there was only “low-quality evidence to support Vitamin D supplementation for the reduction of asthma exacerbations.”
A study of Vitamin D replacement in patients with chronic spontaneous urticaria (CSU)8 yielded more concrete results. The 25(OH)D levels of patients with CSU (n=58) were compared to those of controls (n=45). Patients whose concentrations were lower than 30ng/mL received 300,000 IU/month of Vitamin D3 supplementation.
Serum 25(OH)D concentration was significantly lower in the CSU group compared to healthy controls, and the prevalence of Vitamin D deficiency and insufficiency significantly higher in CSU patients than in healthy controls. After 12 weeks, the patients treated with Vitamin D3 supplementation showed significant improvements in the urticaria activity score (UAS4) and the Chronic Urticaria Quality of Life Questionnaire (CU-Q2oL) scores. The authors concluded that their study “supports the contributing and beneficial effects of Vitamin D in the treatment of CU.”