Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease condition of narrowing of lung airways. Smoking is a well-known etiological factor to develop COPD. Oxidative stress and lung inflammation in COPD may be related to oxidant/antioxidant imbalance. The aim of the present study was to investigate effect of smoking status, disease severity, exacerbations on Oxidative stress and hs-CRP levels in Chronic Obstructive Pulmonary Disease.Total antioxidant capacity (TAC) and total oxidant status (TOS) were determined according to standard protocol. High sensitivity C- reactive protein (hs-CRP) was assessed by
commercially available kit. All the statistical analysis was performed using SPSS v16.0. TAC was significantly low (p<0.001) in patients than controls whereas, no significant difference was observed for TOS. Oxidative stress index (OSI) and hs-CRP levels were significantly elevated in patients than controls. TAC revealed a significant positive association with weight, WC, BMI, WHR, WSR and FVC. OSI was negatively correlated with TAC and WHR. TAC was significantly (p<0.05) higher in non-smokers as compared to smokers. Significantly (p<0.001) high TAC was observed in ex-smokers than current smokers. TOS levels were significantly high (p<0.05) in non-smokers compared to ex-smokers and significantly high (p<0.05) in current smokers than ex-smokers. OSI was significantly high (p<0.05) in current smokers than non-smokers. OSI was significantly high (p<0.001) in current smokers than ex-smokers. Significant difference (p<0.05) for TAC was observed among all the four COPD stages. Significantly (p<0.05) elevated serum hs-CRP levels were observed in moderate COPD than very severe COPD. No statistical difference was observed for TAC, TOS, OSI and hs-CRP in patients with and without
exacerbations. Our data provided further support to the fact that there is higher production of ROS in COPD leading to oxidative stress.