Impact of lung function on exacerbations, health care utilization, and costs among patients with COPD

OBJECTIVE To evaluate the impact of lung function, measured as forced expiratory volume in 1 second (FEV1) % predicted, on health care resource utilization and costs among patients with COPD in a real-world US managed-care population. METHODS This observational retrospective cohort study utilized administrative claim data augmented with medical record data. The study population consisted of patients with one or more medical claims for pre- and postbronchodilator spirometry during the intake period (July 1, 2012 to June 30, 2013). The index date was the date of the earliest medical claim for pre- and postbronchodilator spirometry. Spirometry results were abstracted from patients' medical records. Patients were divided into two groups (low FEV1% predicted [,50%] and high FEV1% predicted [≥50%]) based on the 2014 Global Initiative for Chronic Obstructive Lung Disease report. Health care resource utilization and costs were based on the prevalence and number of discrete encounters during the 12-month postindex follow-up period. Costs were adjusted to 2014 US dollars. RESULTS A total of 754 patients were included (n=297 low FEV1% predicted group, n=457 high FEV1% predicted group). COPD exacerbations were more prevalent in the low FEV1% predicted group compared with the high group during the 12-month pre- (52.5% vs 39.6%) and postindex periods (49.8% vs 36.8%). Mean (standard deviation) follow-up all-cause and COPD-related costs were $27,380 ($38,199) and $15,873 ($29,609) for patients in the low FEV1% predicted group, and $22,075 ($28,108) and $10,174 ($18,521) for patients in the high group. In the multivariable analyses, patients in the low FEV1% predicted group were more likely to have COPD exacerbations and tended to have higher COPD-related costs when compared with patients in the high group. CONCLUSION Real-world data demonstrate that patients with COPD who have low FEV1% predicted levels use more COPD medications, have more COPD exacerbations, and incur higher COPD-related health care costs than those with high FEV1% predicted levels.