CHRONIC OBSTRUCTIVE PULMONARY DISEASE Risk factors of readmission to hospital for a COPD

Background: Exacerbations of chronic obstructive pulmonary disease (COPD) are a leading cause of admission to hospital among men in many countries, although the factors causing exacerbations are largely unknown. The association between readmission for a COPD exacerbation and a wide range of modifiable potential risk factors, after adjusting for sociodemographic and clinical factors, has been assessed. Methods: Three hundred and forty patients with COPD recruited during an admission for an exacer-bation in four tertiary hospitals in the Barcelona area of Spain were followed for a mean period of 1.1 years. Information on potential risk factors, including clinical and functional status, medical care and prescriptions, medication adherence, lifestyle, health status, and social support, was collected at the recruitment admission. A Cox’s proportional hazards model was used to obtain independent relative risks of readmission for COPD. Results: During the follow up period 63 % of patients were readmitted at least once, and 29 % died. The final multivariate model showed the following risk (or protective) factors:>3 admissions for COPD in the year before recruitment (hazard ratio (HR)=1.66, 95 % CI 1.16 to 2.39), forced expiratory vol-ume in 1 second (FEV1) percentage predicted (0.97, 95 % CI 0.96 to 0.99), oxygen tension (0.88