Effectiveness of inhaler types for real-world asthma management: retrospective observational study using the GPRD

Abstract

Purpose:

Results of randomized controlled trials may not predict effectiveness of inhaled corticosteroids (ICS) in real-world clinical practice, where inhaler technique and device characteristics can influence effectiveness. We compared asthma outcomes for ICS delivered via three different inhaler devices: pressurized metered-dose inhaler (pMDI), breath-actuated MDI (BAI), and dry powder inhaler (DPI).

Patients and methods:

This retrospective database study evaluated 1-year outcomes for primary care patients with asthma aged 5–60 years prescribed their first ICS (initiation population) by pMDI (n = 39,746), BAI (n = 9809), or DPI (n = 6792), or their first ICS dose increase (step-up population) by pMDI (n = 6245), BAI (n = 1388), or DPI (n = 1536). Co-primary outcome measures were composite proxy measures of asthma control (no hospital attendance for asthma, oral corticosteroids, or antibiotics for lower respiratory infection) and severe exacerbations (unscheduled hospital admission, emergency room attendance, or oral corticosteroids). Outcomes were adjusted for potential confounding factors identified during a baseline year.

Results:

In the initiation population, adjusted odds ratios (95% confidence intervals [CI]) for asthma control, as compared with pMDIs, were significantly better for BAIs (1.08 [1.02–1.14]) and DPIs (1.13 [1.06–1.21]), while adjusted exacerbation rate ratios (95% CI) were 1.00 (0.93–1.08) and 0.88 (0.81–0.95), respectively. In the step-up population, adjusted odds of asthma control were 1.21 (1.05–1.39) for BAIs and 1.13 (0.99–1.29) for DPIs; adjusted exacerbation rate ratios were 0.83 (0.71–0.98) for BAIs and 0.85 (0.74–0.98) for DPIs, compared with pMDIs.

Conclusion:

Inhaler device selection may have a bearing on clinical outcomes. Differences in real-world effectiveness among these devices require closer evaluation in well-designed prospective trials.

Keywords:

• asthma control
• dry powder inhaler
• breath-actuated inhaler
• metered-dose inhaler
• primary care

Acknowledgements

We thank Martha Joseph and Linda Kemp for their work on the initial analyses.

Access to data from the General Practice Research Database was funded by Merck and Co., Inc., and the analysis was funded by Teva Pharmaceuticals Ltd.

Disclosures

David Price has consultant arrangements with Boehringer Ingelheim, GlaxoSmithKline, Merck, Mundipharma, Novartis, and Teva. He or his research team have received grants and support for research in respiratory disease from the following organizations in the last 5 years: UK National Health Service, Aerocrine, AstraZeneca, Boehringer Ingelheim, GlaxoSmithKline, Merck, Mundipharma, Novartis, Nycomed, Pfizer, and Teva. He has spoken for AstraZeneca, Boehringer Ingelheim, Chiesi, GlaxoSmithKline, Merck, Mundipharma, Pfizer, and Teva. He has shares in AKL Ltd which produces phytopharmaceuticals. He is the sole owner of Research in Real Life Ltd.

John Haughney has received reimbursements for attending symposia, fees for speaking and organizing educational events, funds for research, or fees for consulting from AstraZeneca, Boehringer-Ingelheim, GlaxoSmith-Kline, Merck, Sharp and Dohme, Mundipharma, Novartis, Nycomed, Sanofi-Aventis, and Teva.

Elizabeth V Hillyer has done freelance writing work for Merck, Aerocrine, and Teva Sante (France).

Amanda J Lee receives payment for statistical consultancy from Research in Real Life Ltd.

Neil Barnes has lectured for or done consultancy for GlaxoSmithKline, AstraZeneca, Chiesi, Boehringer, Teva, and Nycomed and has received research support from GlaxoSmithKline, Novartis, and Schering-Plough.

All other authors report no conflicts of interest in this work.