COPD exacerbation frequency and its association with health care resource utilization and costs

Background: Chronic obstructive pulmonary disease (COPD) exacerbations account for a substantial proportion of COPD-related costs. Objective: To describe COPD exacerbation patterns and assess the association between exacerbation frequency and health care resource utilization (HCRU) and costs in patients with COPD in a Medicare population. Methods: A retrospective cohort study utilizing data from a large US national health plan was conducted including patients with a COPD diagnosis during January 1, 2007 to December 31, 2012, aged 40-89 years and continuously enrolled in a Medicare Advantage Prescription Drug plan. Exacerbation frequency, HCRU, and costs were assessed during a 24-month period following the first COPD diagnosis (follow-up period). Four cohorts were created based on exacerbation frequency (zero, one, two, and >= three). HCRU and costs were compared among the four cohorts using chi-square tests and analysis of variance, respectively. A trend analysis was performed to assess the association between exacerbation frequency and costs using generalized linear models. Results: Of the included 52,459 patients, 44.3% had at least one exacerbation; 26.3%, 9.5%, and 8.5% had one, two, and >= three exacerbations in the 24-month follow-up period, respectively. HCRU was significantly different among cohorts (all P<0.001). In patients with zero, one, two, and >= three exacerbations, the percentages of patients experiencing all-cause hospitalizations were 49.7%, 66.4%, 69.7%, and 77.8%, respectively, and those experiencing COPD-related hospitalizations were 0%, 40.4%, 48.1%, and 60.5%, respectively. Mean all-cause total costs (medical and pharmacy) were more than twofold greater in patients with >= three exacerbations compared to patients with zero exacerbations ($27,133 vs $56,033; P<0.001), whereas a greater than sevenfold difference was observed in mean COPD-related total costs ($1,605 vs $12,257; P<0.001). Conclusion: COPD patients frequently experience exacerbations. Increasing exacerbation frequency is associated with a multiplicative increase in all-cause and COPD-related costs. This underscores the importance of identifying COPD patients at risk of having frequent exacerbations for appropriate disease management.