Study on serum zinc levels in asthma

Abstract

Background: Asthma is a chronic inflammatory airway disease characterized by variable respiratory symptoms and reversible airflow limitation. Zinc, an essential trace element with antioxidant and immunomodulatory properties, may influence airway inflammation and asthma outcomes. This study evaluated serum zinc levels in children with asthma and their association with disease severity, asthma control, pulmonary function, and exacerbation frequency.

Methods: This hospital-based cross-sectional comparative study included 120 children aged 6–18 years (60 asthmatic and 60 healthy controls). Asthma diagnosis, severity, and control were assessed according to GINA 2025 guidelines. Serum zinc levels were measured using the colorimetric NITRO-PAPS method, and pulmonary function was evaluated by spirometry. Data were analyzed using SPSS version 28, with p<0.05 considered statistically significant.

Results: Mean serum zinc levels were significantly lower in asthmatic children than in controls (69.68±16.41 vs. 84.47±17.87 µg/dl; p<0.001), with a higher prevalence of hypozincemia (31.7% vs. 15.0%; p=0.031). Lower serum zinc levels were significantly associated with poorer asthma control (p<0.001), greater disease severity (p=0.008), and impaired pulmonary function (FEV₁ <80% predicted; p<0.001). Although hypozincemia increased with exacerbation frequency, the association was not statistically significant (p=0.151).

Conclusion: Reduced serum zinc levels are associated with poor asthma control, increased disease severity, and impaired pulmonary function in children with asthma. Serum zinc may serve as a potential biomarker for disease status and a modifiable factor in asthma management.