1. Cohort Analysis of Exacerbation Rates in Adolescent and Adult Patients Initiating Inhaled Corticosteroids for Asthma: Different Dose-Response Profile by Particle Size.
- Author
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Postma, Dirkje, Kaplan, Alan, Soriano, Joan, Grigg, Jonathon, Guilbert, Theresa, Aalderen, Wim, Roche, Nicolas, Burden, Anne, Hillyer, Elizabeth, Israel, Elliot, and Price, David
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DOSE-effect relationship in pharmacology , *BECLOMETHASONE dipropionate , *ASTHMA diagnosis , *ASTHMA treatment , *INHALATION anesthetics , *PATIENT satisfaction - Abstract
Introduction: Targeting small airway inflammation could lead to improved clinical outcomes in asthma. Previous observational studies concluded that therapy with extrafine-particle [mass median aerodynamic diameter (MMAD) <2 µm] inhaled corticosteroids (ICS) is associated with similar or better odds of achieving asthma control at lower prescribed doses than fine-particle ICS (MMAD = 2-5 µm). However, while it is believed that the dose-response for ICS reaches a plateau at sub-maximal doses, it is not clear whether such a plateau occurs with extrafine-particle ICS. Methods: To evaluate the potential effect of ICS particle size on dose-response of asthma-related outcomes, we studied severe exacerbation rates in a historical patient cohort of UK adults and adolescents with asthma initiating extrafine- or fine-particle ICS. We extracted electronic medical record data centralized at primary care practices, where information from secondary care and hospitalizations is also aggregated. Data were collected over one baseline (pre-initiation) and one outcome year. Results: Of 32,235 patients with asthma (aged 12-80 years), 54% initiated ICS with extrafine-particle ICS and 46% with fine-particle ICS. Overall, mean age (SD) was 41 (17) years; 60% female; 24% current and 20% ex-smokers. We found a greater ( P < 0.001) reduction in exacerbation rate at higher as compared with lower doses of extrafine-particle ICS: for patients initiating on ≤125 µg/day the reduction was −0.016 (95% CI −0.038, 0.006) exacerbations per year and for those initiating on >250 µg/day the reduction was −0.072 (−0.095, −0.049). No significant dose-response relationship was observed for patients initiating on fine-particle ICS [reduction in exacerbations per year: −0.041 (−0.070, −0.012) at the lowest doses and 0.009 (−0.017, 0.036) at the highest, P = 0.856, despite similar exacerbation rates in the baseline period for both cohorts ( P = 0.40)]. Conclusion: Our findings suggest that extrafine-particle ICS is associated with a reduction in exacerbation rates in a dose-dependent fashion in an adult asthma population. This dose-response relationship was not observed with fine-particle ICS. ENCePP Trial Registration: EUPAS8840. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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