Risk factors associated with mortality of COPD patients hospitalised for exacerbation

OBJECTIVE: To investigate factors associated with mortality and assess the changes in arterial blood gas (ABG) in patients hospitalised for exacerbation of chronic obstructive pulmonary disease (COPD). MATERIAL AND METHODS: This was a retrospective analysis of 49 patients (38 men and 11 women) hospitalised in a tertiary care facility for exacerbation of COPD between January 2004 and December 2005. Data on exposures, ABG, blood chemistry, severity of COPD and treatments were collected from patient charts. Survival status was determined by hospital records and telephone contact with the patients or family members. RESULTS: The average age of patients in the study was 71.1±10.9 years (mean±SD), and the majority were in stage IV (25 cases, 51%) or stage III (15 cases, 30.6%). Comorbidity was reported in 42 cases (85.7%). The median duration of hospital stay was 14.8 days (range: 4-70) days. Ten patients (20.4%) received mechanical ventilation (MV) support. Six male and three female patients died (18.4%); 2 in the hospital (4.1%) and 7 during the 2 year followup (14.9%). Mortality was associated with older age (79.7±12.0 vs. 69.2±9.4 years) and MV support (4/9 deceased vs. 6/40 alive). The change in PaCO₂ between the first measurement on admission and during hospitalisation was associated with mortality after discharge (median and range, mmHg, alive: 3 (-29-55.8) and -6 (-10.2-0.1). CONCLUSION: Prospective studies are required to test the predictive value of changes in PaCO₂ for the survival in patients hospitalised for exacerbation of COPD.