Determinants of Onset and Progression of COPD in Young Adults

COPD (Chronic Obstructive Pulmonary Disease) is a Public Health problem due to its impact in the patient's quality of life, high prevalence, growing incidence and socioeconomic implication. COPD natural history and first stages determinants are unknown. Knowing them will help to understand the natural history of the disease and to design interventions that can modify the prognosis of the disease. Study objectives: (1) To characterize an early COPD population from a multidimensional point of view including demographic, social, family and clinical data, lung function, exercise capacity, image, microbiology, quality of life, exacerbations, comorbidities and blood and sputum biomarkers. (2) To compare this patients with smoking subjects, with normal lung function, matched by age, sex and site. (3) To create an early COPD cohort to be followed in the future to understand the complete natural history of the disease. Methods: Design: multicenter cross-sectional study that will allow establishing a well-characterized cohort of early COPD patients for later follow-up. Recruitment will be done in Primary Care settings. Subjects: smokers (\> 10 packs year) between 35-50 years old with a spirometry (normal or obstructive) done in the last year. Diagnosis of COPD will be based on the smoking history and a postbronchodilator test FEV1(Forced Expiratory Volume in the first second) / FVC(Forced Vital Capacity) \< 70%. Age, sex and site matched 'healthy' smoker controls will be compared with the COPD cases. Variables that will be collected in the reference hospitals are: health questionnaires, lung function test, exercise capacity, blood and sputum samples, and low dose CT-scan. Statistical analysis: early COPD patient's characteristics will be described and then, will be compared, with control subjects through a conditional multiple logistic regression analysis.