Abstract
OBJECTIVES: Smoking is the major determinant of developing chronic obstructive pulmonary disease (COPD). A substantial proportion of patients with COPD continue smoking although they have significant respiratory symptoms, exacerbation history and comorbidities. We aimed to find the associated factors and clinical features of the patients who maintain smoking. METHODS: 200 current smokers and 132 former smokers with a spirometry-confirmed diagnosis of COPD were recruited from the outpatient department. Demographic characteristics, smoking backgrounds, treatment status, comorbidities, exacerbation history of the previous year, pulmonary function tests, blood biochemistry, dyspnea scales, symptom scores, and BECK anxiety scores were all recorded. RESULTS: No age and gender differences were found between current and former smokers. Compared to former smokers, current smokers were less qualified, had more cardiovascular diseases, more frequently exposed to tobacco smoke at home and at work place, more severe pulmonary function impairment, longer duration of COPD, longer time of smoking, earlier age of commencement in smoking, higher scores of BECK anxiety scores (BAI), higher levels of inflammatory markers in blood tests p<0.05. In multivariable analysis, lower values of FEV(1)%, higher scores of CAT and BAI, higher levels of platelet and CRP were found to decrease the likelihood of smoking cessation p<0.05. Additionally having diabetes, coronary artery disease and hypertension were inversely correlated with quitting smoking p<0.05. CONCLUSION: COPD is a systemic inflammatory disease. We found over half of the patients with COPD were currently smoking, despite the severity of their airflow limitation, symptoms and even the comorbidities. Furthermore, 2 out of 5 of the current smokers reported having moderate to severe anxiety. Dyspnea and inflammatory markers had negative effects on smoking cessation, and anxiety might be the cause that led these patients to keep smoking.