Biomarkers used to evaluate smoking in COPD patients

Abstract

Introduction: Chronic obstructive pulmonary disease (COPD) is a complex disease with oxidative stress and inflammation playing an important role in its development and evolution, even after the patients quit smoking.

Material and methods: The purpose of this study was to evaluate the biochemical (ASAT, ALT, urea, creatinine, glucose, uric acid, uric acid / creatinine UCR ratio) and hematological parameters for 53 patients (smokers, non-smokers, ex-smokers), depending on the smoking status (packs years -PY) and also identifying markers to evaluate tobacco exposure and the severity of COPD.

Results and discussions: The Man-Whitney test showed a statistically significant difference in smokers vs non-smokers (COPD II and III stages) (p˂0.05) given by serum uric acid, urea and PY. In the smokers and ex- smokers groups, the statistical difference (p˂0.05) was indicated by serum uric acid and the number of eosinophils. The UCR ratio was positively correlated with the number of eosinophils (p˂0.05; r = 0.45) and serum glucose (p˂0.05; r = 0.50) for all 3 groups (smokers, non-smokers and ex-smokers). The discriminant analysis indicates a very good separation of the classes evaluated especially for smokers and non-smokers, respectively ex-smokers and non-smokers (Figure 1) and also shows a direct dependence between nicotine consumption (PY), serum uric acid levels and evaluation of the UCR ratio.

Conclusions: Evaluation of serum uric acid as well as the ratio of UCR in patients with or without nicotine dependence shows a statistically significant difference between smokers and non-smokers in terms of oxidative stress and could indicate a direct association with the severity of COPD.