Background: Recurrent exacerbations are common in COPD patients. Limited information exists regarding exacerbation frequency in COPD patients from epidemiologic studies. We examined the frequency of self-reported exacerbations and the factors influencing exacerbation frequency among COPD patients in a population-based study conducted in Latin America.
Methods: We used a post-bronchodilator FEV(1)/FVC ratio of < 0.70 to define COPD. Exacerbation was self-reported and defined by symptoms (deterioration of breathing symptoms that affected usual daily activities or caused missed work).
Results: Spirometry was performed in 5,314 subjects. There were 759 subjects with airflow limitation; of these, 18.2% reported ever having had an exacerbation, 7.9% reported having an exacerbation, and 6.2% reported having an exacerbation requiring at least a doctor visit within the past year. The proportion of individuals with an exacerbation significantly increased by Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages, from 4.2% in stage 1 to 28.9% in stages 3 and 4. The self-reported exacerbation rate was 0.58 exacerbations per year. The rate of exacerbations requiring at least a doctor visit and length of stay in hospital due to exacerbations also increased as COPD severity progressed. The factors associated with having an exacerbation in the past year were dyspnea, prior asthma diagnosis, receiving any respiratory therapy, and disease severity of GOLD stages 3 and 4.
Conclusions: The proportion of individuals with airflow limitation and self-reported exacerbation increases as the disease severity progresses. Dyspnea, prior asthma diagnosis, receiving any respiratory therapy, and more severe obstruction were significantly associated with having an exacerbation in the past year.