Smoking cessation can improve quality of life among COPD patients: Validation of the clinical COPD questionnaire into Greek

The aim of this study was to validate the Clinical COPD Questionnaire (CCQ) into Greek and with such to evaluate the quality of life in patients with different stages of COPD, as also assess their quality of life before and after smoking cessation.The internal validity of questionnaire was high (Cronbach's a = 0.92). The reliability of equivalent types in 16 stabilized patients also was high (ICC = 0.99). In general the domains within the CCQ were strongly correlated with each other, while each domain in separate was strongly correlated with the overall CCQ score (r2 = 0.953, r2 = 0.915 and r2 = 0.842 in regards to the functional, symptomatic and mental domain, respectively). The CCQ scores were also correlated with FEV1, (r2 = -0.252, p < 0.001), FEV1/FVC, (r2 = -0.135, p < 0.001) as also with the quality of life questionnaire SF-12 (r2 = -0.384, p < 0.001). Smoking cessation also lead to a significant reduction in CCQ score and increase in the SF-12 score.The self administered CCQ indicates satisfactory validity, reliability and responsiveness and may be used in clinical practice to assess patient quality of life. Moreover the CCQ indicated the health related quality of life gains attributable to smoking cessation among COPD patients, projecting smoking cessation as a key target in COPD patient management.Chronic obstructive pulmonary disease (COPD) is a preventable and treatable disease. Its pulmonary component is characterized by airflow limitation that is not fully reversible. This airflow limitation is usually progressive and associated with an abnormal inflammatory response of the lung to noxious particles or gases, such as those emitted during smoking [1]. COPD has considerable implications on the quality of life of patients and may overload the health care system and increase health care expenditure [1,2]. Moreover at a global level, COPD is a significant public health issue and is the fourth leading cause of illness and mortality worldwide, while up to the