PURPOSE: To compare exacerbations between COPD patients using multiple- and single-long-acting inhalers.
METHODS: Patients with ≥2 COPD medical claims, ≥40 years old, ≥18 months continuous plan enrollment, and ≥2 prescriptions for a long-acting inhaler within 1 year were selected in the MarketScan database (2004−2008). Patients were classified as single-inhaler users (did not use concomitantly >1 long-acting inhaler) or multiple-inhaler users (filled ≥2 different LABA, LAMA, ICS or ICS/LABA inhalers concomitantly). Groups were matched on age, gender, index year, comorbidities, COPD sub-type, prior COPD treatments, and prior number of exacerbations. Patients were followed for 12 months post-index date, (a randomly selected prescription date for single-inhaler users and a randomly selected date among concomitant prescription dates for multiple-inhaler users). Exacerbations were defined as 1) a medical claim with a COPD exacerbation diagnosis, 2) a claim for a medical service received during hospitalization or ER visit with a COPD diagnosis, or 3) a prescription for an antibiotic or corticosteroid filled within 7 days after an outpatient visit with a COPD diagnosis. Number of exacerbations and time to first exacerbation were estimated using linear and Cox-proportional hazards regression models, respectively. A sensitivity analysis was conducted on patients with ≥1 COPD exacerbation during the study period (poorly controlled group).
RESULTS: 23,494 patients were grouped into 11,747 matched pairs. 4,292 (36.5%) single-inhaler users and 5,452 (46.4%) multiple-inhaler users experienced an exacerbation during the study period. On average, after adjustment for confounding factors (age, gender, prior COPD treatments, and comorbidities), multiple-inhaler users experienced significantly more exacerbations (0.524; p< 0.0001) and shorter time to first exacerbation (hazard ratio [HR]=1.40; p< 0.0001) compared to single-inhaler users. Results were consistent among the poorly controlled group (0.625; p< 0.0001 and HR=1.09; p=.0147, respectively).
CONCLUSION: Multiple-inhaler use was associated with more COPD exacerbations and shorter time to first exacerbation when compared to single-inhaler use.
CLINICAL IMPLICATIONS: Multiple-inhaler use is associated with a greater risk of exacerbations than single-inhaler use. This may be partially explained by a complicated medication regimen. Simplified inhaler regimens may improve COPD outcomes.
DISCLOSURE: Andrew Yu, Grant monies (from industry related sources) Funding for this research was provided by Forest Laboratories, Inc. Analysis Group, Inc., has received research funds from Forest Laboratories, Inc.; Employee Andrew Peng Yu, Annie Guérin, Diego Ponce de Leon Barido, Karthik Ramakrishnan and Eric Wu are employees of Analysis Group, Inc. Juliana Setyawan, Michelle Dembiski and Steve Blum are employees of Forest Laboratories, Inc.; No Product/Research Disclosure Information