Cost saving of switching to equivalent inhalers and its effect on health outcomes. Issue 11 (5th August 2019)

• Record Type: Journal Article
• Authors: Bloom, Chloe I; Douglas, Ian; Olney, Jack; D'Ancona, Grainne; Smeeth, Liam; Quint, Jennifer K
• Is Part Of: Thorax. Volume 74:Issue 11(2019)
• Page Start: 1078
• Page End: 1086
• Publication Date: 2019-08-05
• Subjects: inhaler devices -- asthma -- COPD epidemiology; Chest -- Diseases -- Periodicals; Thorax; Chest -- Diseases; Periodicals; Periodicals; 617.54
• DOI: 10.1136/thoraxjnl-2018-212957
• Languages: English
• ISSNs: 0040-6376

Abstract

Abstract : Background: Switching inhalers to cheaper equivalent products is often advocated as a necessary cost saving measure, yet the impact on patient's health and healthcare utilisation has not been measured. Methods: We identified asthma and chronic obstructive pulmonary disease (COPD) patients from UK primary care electronic healthcare records between 2000 and 2016. A self-controlled case series was used to estimate incidence rate ratios (IRR); comparing outcome rates during the risk period, 3 months after the exposure (financially motivated switch), and control periods (preswitch and postrisk period). Four outcomes were assessed: disease exacerbation, general practitioner consultation, non-specific respiratory events and adverse-medication events. Medication possession ratio (MPR) was calculated to assess adherence. 2017 National Health Service indicative prices were used to estimate cost differences per equivalent dose. Results: We identified a cohort of 569 901 asthma and 171 231 COPD regular inhaler users, 2% and 6% had been switched, respectively. Inhaler switches between a brand-to-generic inhaler, and all other switches (brand-to-brand, generic-to-generic, generic-to-brand), were associated with reduced exacerbations (brand-to-generic: IRR=0.75, 95% CI 0.64 to 0.88; all other: IRR=0.79, 95% CI 0.71 to 0.88). Gender, age, therapeutic class, inhaler device and inhaler-technique checks did not significantly modify this association (p<0.05). The rate of consultations, respiratory-events and adverse-medication events did not change significantly (consultations: IRR=1.00, 95% CI 0.99 to 1.01; respiratory-events: IRR=0.96, 95% CI 0.95 to 0.97; adverse-medication-events: IRR=1.05, 95% CI 0.96 to 1.15). Adherence significantly increased post-switch (median MPR: pre-switch=54%, post-switch=62%; p<0.001). Switching patients, in the cohort of regular inhaler users, to the cheapest equivalent inhaler, could have saved around £6 million annually. Conclusion: Switching to an equivalent inhaler in patients with asthma or COPD appeared safe and did not negatively affect patient's health or healthcare utilisation.