Efficacy of Zinc Supplementation in Reducing the Severity of Childhood Asthma Exacerbation

Background: Asthma is the most common chronic disorder of the airways in children. Airway inflammation is considered as one of the pathogenesis and pathophysiology of asthma. Zinc is an immunoregulatory agent with antioxidant, anti-inflammatory and anti-apoptotic properties. Zinc deficiency has demonstrated an association with the risk of asthma.

Objective: This study aimed to evaluate the efficacy of zinc supplementation in reducing the severity of childhood asthma exacerbation.

Methods: Forty-two children with asthma exacerbation who admitted to the hospital were randomized to receive either zinc bis-glycinate (30mg elemental zinc/day) or a placebo in adjuvant to the standard treatment. The Pediatric Respiratory Assessment Measure (PRAM) was used to measure the asthma severity. The primary outcome was a change in asthma severity from the baseline to the end of study. The secondary outcomes were change in serum zinc levels from the baseline to the end of study and prevalence of zinc deficiency.

Results: Baseline asthma severity scores did not show a significant difference between groups. However, the PRAM score in the zinc group showed a more rapid decrease compared to the control group at the 24-hour (2.2±1.3 vs 1.2±1.3; p-value=0.015) and 48-hour (3.4±2.0 vs 2.2±1.8; p-value=0.042) intervals. At admission, overall mean serum zinc level was 63.8 μg/dL and 57.1% of children had zinc deficiency with no difference in prevalence between groups. PRAM scores did not differ between children with low and normal zinc status. Compared to baseline, zinc levels increased by 32.3 μg/dL and 14.2 μg/dL in the zinc and control groups, respectively. However, zinc levels at the end and length of hospital stay were not significantly different between the groups.

Conclusion: Zinc supplementation as the adjuvant therapy to the standard treatment during asthma exacerbation resulted in rapid lessening of severity.