Variables clínicas y funcionales asociadas al riesgo de muerte en el seguimiento a largo plazo en pacientes con enfermedad pulmonar obstructiva crónica / Clinical and functional variables associated to long-term mortality in COPD patients

RESUMEN

Background: Identifying risk factors for long-term mortality in patients with chronic obstructive pulmonary disease (COPD) could improve their clinical management. Aim: To examine the clinical variables associated to long-term mortality in a cohort of COPD patients. Patients and Methods: A clinical and respiratory functional assessment, chest computed tomography and clinical follow up for five years was carried out in 202 COPD patients aged 66 ± 9 years (59% males), active or former smokers of 10 or more pack-years. Results: Thirty four percent of patients were active smokers, consuming 46 ± 23 packs/year, 86% had comorbidities, especially chronic cardiovascular and metabolic diseases. Forty-six patients died in the five years follow-up (5-year mortality was therefore 22.8%). In the univariate analysis, the main risk factors associated to long-term mortality were an older age, male sex, dyspnea severity, severe exacerbation risk, chronic respiratory failure, magnitude of lung emphysema, airflow obstruction and lung hyperinflation, reduction of thigh muscle cross-sectional area and physical activity limitation. In the multivariate analysis, the three independent risk factors for long-term mortality were dyspnea severity, chronic hypoxemia and exercise limitation measured with the six minutes' walk test. Conclusions: Systematic clinical assessment allowed to identify the main risk factors associated with long-term mortality in patients with COPD, which could be used in planning preventive and management programs aimed at the high-risk population.