Objective
To describe the burden of moderate to severe exacerbations and all-cause mortality; the secondary objectives were to analyze treatment patterns and changes over follow-up.
Design
Observational, multicenter, retrospective, cohort study with a three year follow-up period.
Setting
Ten Italian academic secondary- and tertiary-care centers.
Participants
Patients with a confirmed diagnosis of COPD referring to the outpatient clinics of the participating centers were retrospectively recruited.
Primary and Secondary Outcome Measures
Annualized frequency of moderate and severe exacerbations stratified by exacerbation history prior to study enrollment. Patients were classified according to airflow obstruction, GOLD risk categories, and divided in 4 groups: A = no exacerbations; B = 1 moderate exacerbation; C = 1 severe exacerbation; D = ≥2 moderate and/or severe exacerbations. Overall all-cause mortality stratified by age, COPD category, and COPD therapy. A logistic regression model assessed the association of clinical characteristics with mortality.
Results
1111 patients were included (73% males), of which 41.5% had a history of exacerbations. As expected, the proportion of patients experiencing ≥1 exacerbation during follow-up increased according to pre-defined study risk categories (B: 79%, C: 84%, D: 97.4%). Overall, by the end of follow-up, 45.5% of patients without a history of exacerbation experienced an exacerbation (31% of which severe), and 13% died. Deceased patients were significantly older, more obstructed and hyperinflated, and more frequently active smokers compared with survivors. Severe exacerbations were more frequent in patients that died (23.5%, vs 10.2%; p-value: 0.002). Chronic heart failure and ischemic heart disease were the only comorbidities associated with a higher odds ratio (OR) for death (OR: 2.2, p-value: 0.001; and OR: 1.9, p-value: 0.007). Treatment patterns were similar in patients that died and survivors.
Conclusion
Patients with a low exacerbation risk are exposed to a significant future risk of moderate/severe exacerbations. Real life data confirm the strong association between mortality and cardiovascular comorbidities in COPD.