An oxidant/antioxidant imbalance is thought to play an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). We hypothesized that antioxidant capacity reflected by erythrocyte glutathione peroxidase (GPx) activity will be lower, and serum levels of the lipid peroxidation product malondialdehyde (MDA) will be higher in patients with mild compared to those with severe COPD.
Erythrocyte GPx activity and serum levels of MDA were measured in 103 consecutive patients with stable COPD. Pulmonary function tests were assessed using bodyplethysmography. Differences between the groups were assessed by one-way ANOVA.
Moderate COPD (FEV1 50-80%) was present in 31, severe (FEV1 30-50%) in 51, and very severe COPD (FEV1 < 30%) in 21 patients. Both, erythrocyte GPx activity and serum MDA levels differed significantly between the moderate, severe, and very severe COPD groups (GPx: 47.7±2.9 versus 45.2±1.8, and 37.4±2.3 u/gHb, respectively, p<0.05; MDA: 2.1±0.9 versus 2.3±0.1, and 2.5±0.1 nmol/ml, respectively, p<0.05).
Findings of the present study suggest that antioxidant capacity reflected by erythrocyte GPx activity and serum levels of the lipid peroxidation product MDA are linked to the severity of COPD. The lowest erythrocyte GPx activity and the highest serum MDA levels were seen in patients with very severe COPD.
In patients with stable COPD, erythrocyte GPx activity and serum MDA levels may serve as additional markers of disease severity.
Ruzena Tkacova, None.