Comparative study of pulmonary functions and oxidative stress in smokers and non-smokers

Chronic Obstructive Pulmonary Disorder (COPD) is projected to rank third leading cause of deaths by 2030 as per WHO. COPD is a multi-etiological disease. The airflow dysfunction is usually progressive, associated with an abnormal inflammatory response of the lungs to noxious particles or gasses. As the lung is exposed to high levels of oxygen, it is more susceptible to oxidants mediated injury. Gender based differences are identifiable risk factors. Smoking is found to be a major risk factor in the causation of COPD resulting in oxidative stress . The aim of the present study is to evaluate the oxidant antioxidant imbalance in healthy non smoker controls and smokers with COPD. A total of 60 control (healthy non smokers) and 121 smokers having COPD were studied. The mean age is more in smoker group as compared to healthy controls, which identifies advancing age as a risk factor for COPD. The mean BMI and weight of smoker group is reduced as compared to control group. GOLD 2008 criteria was used to assess lung functions. Lung functions namely FEV1, FVC, FEV1/FVC% and FEV1% Predicted showed significant reduction in smoker group as compared to healthy non smoker controls. MDA in control and smoker group (1.09 +/- 0.09 and 1.41 +/- 0.23 nmol/ml respectively) showed significant changes (P < 0.001). Our results also demonstrate significant reduction in anti oxidant enzymes namely SOD (units/mg of serum protein), Catalase (units/mg of serum protein) and GPX (nmol of NADPH oxidized/ min/mg of serum protein) in smoker group as compared to healthy controls. On the basis of study it is concluded that smoking, gender and oxidant antioxidant imbalance are identifiable risk factors in COPD.