Asthma control with extrafine-particle hydrofluoroalkane-beclometasone vs. large-particle chlorofluorocarbon-beclometasone: a real-world observational study

作者：Barnes N; Price D^*; Colice G; Chisholm A; Dorinsky P; Hillyer E V; Burden A; Lee A J; Martin R J; Roche N; von Ziegenweidt J; Israel E

来源：Clinical and Experimental Allergy, 2011, 41(11): 1521-1532.

DOI：10.1111/j.1365-2222.2011.03820.x

• asthma
• beclometasone dipropionate
• inhaled corticosteroid
• lung deposition
• observational study
• particle size

Background The extrafine-particle formulation of hydrofluoroalkane-beclometasone (EF HFA-BDP; Qvar (R)) demonstrates improved total and small airway deposition compared with large-particle chlorofluorocarbon (CFC)-BDP. In some short-term studies, EF HFA-BDP provides greater effects on lung function than CFC-BDP, and hence is recommended to be prescribed at a lower dose, but whether there are differences in asthma outcomes during long-term treatment is unknown.
Objective To compare the effectiveness of EF HFA-BDP vs. CFC-BDP over 1 year.
Methods This retrospective matched cohort study examined outcomes in a large primary care database for patients aged 5-60 years with asthma receiving their first inhaled corticosteroid (ICS) prescription (initiation population) or first ICS dose increase (step-up population) by a pressurized metered-dose inhaler (pMDI) as EF HFA-BDP or CFC-BDP. Patients were matched on baseline demographic and asthma severity measures in EF HFA-BDP: CFC-BDP ratios of 1 : 3 and 1 : 2 for initiation and step-up populations, respectively. Step-up patients were matched also on ICS dose during a baseline year. Co-primary endpoints were asthma control (composite measure comprising no recorded hospital attendance for asthma, oral corticosteroids, or antibiotics for lower respiratory infection) and exacerbation rate during the outcome year.
Results For the initiation population (EF HFA-BDP n = 2882; CFC-BDP n = 8646), adjusted odds of achieving asthma control with EF HFA-BDP vs. CFC-BDP was 1.15 (95% CI 1.02-1.28). For the step-up population (n = 258 and 516), adjusted odds of asthma control with EF HFA-BDP was 1.72 (95% CI 1.14-2.56). EF HFA-BDP was prescribed at a median dose half that of CFC-BDP.
Conclusion and Clinical Relevance During 1 year after initiating or stepping up ICS therapy by pMDI, patients who received EF HFA-BDP were more likely to achieve asthma control than those receiving CFC-BDP. These findings suggest that ICS formulation, particle size, and deposition characteristics play important roles in real-life effectiveness of asthma therapy. This study shows that an EF-particle formulation of beclometasone can be used at half the dose of the large-particle formulation with at least as good clinical outcomes.

• 出版日期2011-11