Economic impact of using inhaled corticosteroids without prior exacerbation among elderly patients with chronic...

To assess the economic impact of initiating inhaled corticosteroids (ICS) without evidence of prior exacerbation among elderly patients with chronic obstructive pulmonary disease (COPD) in the US.

This retrospective study used administrative claims to identify newly diagnosed COPD patients between 1/1/2005 and 6/30/2006 who were dispensed ICS. The dispense date of the first ICS was set as the index date. Patients with prior diagnoses for asthma, cystic fibrosis, or lung cancer were excluded. Cohorts were constructed based on whether ICS therapy was concordant with recommended guidelines of having prior COPD exacerbation. Each COPD patient with prior exacerbation was matched to four patients without exacerbation based on age, gender, Charlson Comorbidity Index, and whether COPD diagnosis code was not elsewhere specified (i.e., 496). Multivariate regressions were estimated to assess the association between use of ICS therapy without prior exacerbation and total healthcare costs, controlling for demographics and clinical characteristics.

The study included 3650 patients: 730 with prior exacerbation and 2920 without prior exacerbation. Patients were 76 years of age and 54% were male. Those with prior exacerbation were more likely to have inpatient stays both prior to (74.4 vs. 44.1%, p<0.05) and following (37.0 vs. 33.1%, p<0.05) the index date. Controlling for patient characteristics, patients who were dispensed ICS without prior exacerbation had $1859 higher in total costs (p<0.05) compared to patients with prior exacerbation during the 12 months following ICS initiation.

The retrospective design of this study limits the interpretation of findings as association and not causality. This study is subject to selection bias due to unobservable confounders.

Among COPD patients, initiation of ICS without prior exacerbation appears to be associated with increased healthcare costs. These findings suggest that ICS initiation without evidence of exacerbation as consistent with guidelines is associated with adverse economic consequences.