Background: We analyzed the clinical characteristics and outcomes in non-frequent exacerbation patients with chronic obstructive pulmonary disease (COPD).
Methods: In this retrospective cohort study, we enrolled patients with stable COPD from 12 hospitals. Non-frequent exacerbation was defined as less than two times of exacerbations in the past year. The non-frequent exacerbation patients were classified into less and more symptomatic groups based on the COPD Assessment Test (CAT) and modified Medical Research Council (mMRC). Finally, the non-frequent exacerbation patients with less and more symptomatic were classified into the long-acting muscarinic antagonist (LAMA), long-acting β 2-agonist (LABA)+inhaled corticosteroids (ICS), LABA+LAMA, and LABA+LAMA+ICS groups. Minimum clinically important difference (MCID) was defined as a CAT score decrease of ≥ 2 during six months of follow-up. We recorded the number of exacerbations and mortality during one year of follow-up.
Results: A total of 834 (67.5%) non-frequent exacerbation patients with COPD were included in this study. The non-frequent exacerbation patients had a higher education level and body mass index (BMI), and lower CAT and mMRC scores (P < 0.05). In addition, the non-frequent exacerbation patients had lower mortality and risk of future exacerbation, and were more likely to attain MCID (P < 0.05). Furthermore, the non-frequent exacerbation patients with more symptomatic COPD treated with LABA+LAMA or LABA+LAMA+ICS were more likely to attain MCID and had a lower risk of future exacerbation (P < 0.05). However, there were no significant differences among the different inhalation therapies in non-frequent exacerbation patients with less symptomatic COPD.
Conclusion: The non-frequent exacerbation patients with COPD had a higher education level and BMI, a lower symptom burden, and better outcomes. In addition, LABA+LAMA should be recommended to non-frequent exacerbation patients with more symptomatic COPD, while mono-LAMA should be recommended to non-frequent exacerbation patients with less symptomatic COPD as the initial inhalation therapy.
Keywords: chronic obstructive pulmonary disease, non-frequent exacerbation, minimum clinically important difference, mortality, inhalation therapy