The impact of total antioxidant capacity on pulmonary function in asthma patients

BACKGROUND: Oxidative stress, mediated by an imbalance between oxidants and antioxidants, contributes significantly to the pathogenesis of asthma. OBJECTIVE: To evaluate the impact of serum total antioxidant capacity (TAC) on the pulmonary function of Korean asthma patients. METHOD: A total of 104 adult asthma patients enrolled from the COREA (Cohort for Reality and Evolution of Adult Asthma in Korea) programme participated in the study. Baseline clinical parameters at enrolment, and the results of pulmonary function tests at baseline and 1 and 2 years after enrolment were collected. TAC at baseline was measured using a Trolox-equivalent antioxidant capacity assay. Patients were divided into two groups based on TAC levels, and various clinical parameters were compared. RESULT: Serum TAG levels correlated with forced expiratory volume in 1 second (FEV1) at baseline (r = 0.22, P = 0.03). The group with higher baseline TAC levels maintained greater mean FEV1 both 1 and 2 years after enrolment, even after adjusting for sex, age, height, weight, body mass index and smoking status. CONCLUSION: These results suggest an important link between serum TAC levels and pulmonary function, indicating that higher TAG levels may be a biomarker for favourable prognosis in asthma patients.The authors thank K A Moon for excellent technical support in measuring total serum antioxidant capacity. This work was supported by grant no. 20090086092 from the National Research Foundation of Korea funded by the Korean government to YSC, and grant no. A102065 from the Health 21 R&D project of the Ministry of Health & Welfare and Family, Republic of Korea, to H BM