Predicting One-year Mortality After a "First" Hospitalization for Chronic Obstructive Pulmonary Disease: An Eight-Variable Assessment Score Tool

Several authors have studied predictors of outcomes following a hospitalization for chronic obstructive pulmonary disease (COPD); however, few have reported outcomes following a first hospitalization for COPD. The objective is to develop a predictive mortality risk model in patients surviving a first hospitalization for COPD. This is a retrospective cohort study using linked administrative and clinical data. The cohort included 1129 patients of 40-84 years, discharged alive from a hospitalization for COPD in a regional hospital (Sherbrooke, Canada) between 04/2006 and 03/2013 and to whom were prescribed at least two COPD drugs during their hospitalization. One-year mortality was analysed using logistic regression on a derivation sample and validated on a testing sample. In total, 141 (12.5%) patients died within one year from discharge of their first hospitalization for COPD. Predictors were: older age (OR (95% CI): 1.055 (1.026-1.085)), male sex (OR (95% CI): 1.474 (0.921-2.358)), having a severe COPD exacerbation (OR (95% CI): 2.548 (1.571-4.132)), higher hospital length of stay (OR (95% CI): 1.024 (0.996-1.053)), higher Charlson co-morbidity index (OR (95% CI): 1.262 (1.099-1.449)), being diagnosed of cancer (OR (95% CI): 2.928 (1.456-5.885)), the number of prior all-cause hospitalizations (OR (95% CI): 1.323 (1.097-1.595)), and a COPD duration exceeding 3 years (OR (95% CI): 1.710 (1.058-2.763)). A simple clinical prognosis tool is proposed and shows good discrimination in both the derivation and validation cohorts (c-statistic >0.78). One over eight patients discharged alive from a first COPD hospitalization will die the following year. It is thus important to identify higher-risk patients in order to plan and manage appropriate treatment.