Abstract

The purpose of this study was to investigate the characteristics and survival of patients with COPD and asthma-COPD overlap (ACO) and how these patient groups differ from each other. We examined the impact of different comorbidities, multimorbidity, lung function and other factors have on survival in COPD and ACO patients. We also examined the causes of death to determine how many patients die of other than respiratory diseases. This retrospective study includes 214 patients with an exacerbation of COPD requiring hospitalisation during the year of 2005. The patients were followed up until the end of year 2015. The survival of ACO patients was significantly higher than COPD patients (4.7 vs. 1.7 years, p = 0.001). Poor lung function predicted worse survival in both patient groups, but the prognosis was still better in ACO patients with both FEV1 over and under 50% of predicted (median survival 8.4 years vs. 5.8 years, p < 0.001) compared to COPD (4.9 and 3.1 years, respectively). In this study setting, the negative effect of having three or more comorbidities on survival was significant in both groups. We didn’t see major differences in the profiles of comorbidity patterns, in the underlying cause of deaths or in the pulmonary functions between ACO and COPD groups at the beginning of follow-up. Patients with a BMI over 25 seemed to have a trend for better survival (p = 0.055), but no differences were found between ACO and COPD groups.