PURPOSE: To compare resource utilization and costs between COPD patients treated with multiple- versus 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). Single- and multiple-inhaler users 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 after the index date, (defined as a randomly selected prescription date for single-inhaler users and a randomly selected date among concomitant prescription dates for multiple-inhaler users). Outcomes measured during the 1-year post-index period included number of healthcare services (hospitalizations, emergency room visits, urgent care, and outpatient visits) and healthcare costs (2008 US$). Adjusted incidence rate ratios (IRRs) and incremental costs between the 2 cohorts were estimated from a managed care perspective using negative binomial and generalized nonlinear models, respectively.
RESULTS: 23,494 patients were grouped into 11,747 matched pairs. After adjusting for confounding factors, multiple-inhaler users incurred significantly more hospitalizations (IRR=1.20; p< 0.0001), outpatient visits (IRR=1.06; p< 0.0001), and urgent care days (IRR=1.10; p< 0.0001) compared to single-inhaler users, resulting in higher incremental all-cause healthcare costs for multiple inhaler users (total healthcare [$3,319; p< 0.0001], medical [$1,586; p< 0.0001], and pharmacy [$1,776; p< 0.0001]). Similarly, incremental costs for COPD-related healthcare costs were higher for multiple-inhaler users than single-inhaler users.
CONCLUSION: Multiple-inhaler users had higher healthcare resource utilization and costs compared to single-inhaler users, even after controlling for potential confounding factors.
CLINICAL IMPLICATIONS: Previous work has shown that multiple-inhaler use is associated with lower adherence than single-inhaler use, which may partially explain the increased healthcare resource utilization and costs for multiple-inhaler users. Reducing the inhaler burden for COPD patients may reduce healthcare resource utilization and associated costs.
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, Jipan Wie 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