Clinical and economic burden of eosinophilic COPD in a large retrospective US cohort

Abstract

Purpose: We sought to describe clinical and economic outcomes for COPD patients by blood eosinophil (EOS) count. Methods: This retrospective cohort study of COPD patients used data from the Practice Fusion electronic medical records (EMR) database linked to Symphony Health Solutions transactional pharmacy, medical, outpatient, and inpatient claims data to evaluate COPD-related and all-cause health care resource utilization and cost in the 12-month period following the date of each patient’s greatest recorded blood eosinophil count during the 27-month period from January 2014 to March 2016. A post-index moderate exacerbation was defined as an outpatient or emergency care visit for COPD and a prescription for oral corticosteroid and/or antibiotics within 10 days of the visit. Severe exacerbation was defined as an inpatient hospitalization with COPD as primary diagnosis. Results: Of 48,090 EMR patients, 39,939 (83.1%) had a charge in the claims data both pre-and post-index (mean age 67.2 years, 58.3% female), 17,397 (43.6%) had EOS ≥220 cells/µL. Moderate and severe exacerbations were more frequent for patients with EOS≥220 cells/µL compared with those with EOS <220 cells/µL (moderate: 6.8% vs 6.1%, p<0.05; severe: 3.1% vs 2.5%, p<0.001). After adjustment for baseline clinical characteristics, each 100-unit increase in EOS count was associated with a significant 2.24% increase in total all-cause costs and 4.54% increase in total COPD-related costs (p<0.001 for both). COPD-related costs were significantly greater for patients with an EOS count of ≥220 cells/µL compared with those with EOS <220 cells/µL (p<0.001). These costs appear to have been driven by a greater percentage of patients in the ≥220 cells/µL cohort with COPD-related resource use including hospitalization, office visits, ambulatory procedures and pharmacy prescriptions. Conclusion: COPD patients with EOS counts ≥220 cells/µL were more likely to have had moderate or severe exacerbations and greater cost of care than those with EOS <220 cells/µL.