White blood cells, FeNO, glutathione, 8-oxodG and 8-isoprostane in respiratory diseases

Inflammation and oxidative stress (OS) play an important role in pathogenesis of respiratory diseases. Such biomarkers as fractional exhaled nitric oxide (FeNO), white blood cells, glutathione, urinary 8-oxodG and 8-isoprostane can serve in evaluating clinical course of the disease. We aimed at estimating the association of biomarkers of OS and inflammation with current asthma (CA), past asthma (PA) and chronic bronchitis (CB). The data from GEIRD survey (www.geird.org) have been used in this study. The hierarchic outcome variable was built to achieve mutually exclusive diseases, i.e. Controls (no respiratory disorders, n=549), CA (no PA, n=404), PA (no CA, n=185), CB (no CA, PA, n=92). Multinomial logistic regressions were applied to analyze associations, adjusting for age, BMI, sex, cohort, centre, smoke, comorbidities and alcohol. Relative Risk Ratios (RRR) for one standard deviation increase were adduced for all biomarkers. Glutathione (mg/ml) was higher in subjects with CB (RRR=1.77, CI(1.18-3.07)). FeNO (ppm) was higher in CA (RRR=1.47, CI(1.19-1.82)). Basophils (e+06/ml) had higher levels in CA (RRR=1.48, CI(1.20-1.84)) and CB(RRR=1.51, CI(1.01-2.25)); eosinophils (e+06/ml) were higher in CA (RRR=2.37, CI(1.79-3.13)), PA (RRR=1.79, CI(1.30-2.47)) and CB (RRR=2.14, CI(1.42-3.22)); leucocytes (e+06/ml) were increased in CA (RRR=1.34, CI(1.07-1.67)); lymphocytes (e+06/ml) had higher levels in CA (RRR=1.27, CI(1.03-1.55)) and CB (RRR=1.53, CI(1.05-2.25)). Our results showed that biomarkers of inflammation and OS were differently associated with asthma and chronic bronchitis, suggesting that they might be useful in phenotyping respiratory diseases.