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Bronchial Thermoplasty: A Novel Therapeutic Approach to Severe Asthma
Published on: November 4, 2010
Disease Burden and Long-Term Risk of Persistent Very Poorly Controlled Asthma: TENOR II
Tmirah Haselkorn1, Stanley J Szefler2, Bradley E Chipps3
1EpiMetrix, Inc, Los Altos, Calif.
Background:
Severe/difficult-to-treat disease occurs in 5% to 10% of patients with asthma, but accounts for more than 50% of related economic costs. Understanding factors associated with persistent very poorly controlled (VPC) asthma may improve outcomes.
Objective:
To characterize persistent VPC asthma after more than 10 years of standard of care.
Methods:
The Epidemiology and Natural history of asthma: Outcomes and treatment Regimens (TENOR) II (N = 341) was a multicenter, observational study of patients with severe/difficult-to-treat asthma with a single, cross-sectional visit more than 10 years after TENOR I. Persistent VPC asthma was defined as VPC asthma at TENOR I and TENOR II enrollment; without VPC asthma was defined as well- or not well-controlled asthma at either or both visits. Multivariable logistic regression assessed long-term predictors of persistent VPC asthma using TENOR I baseline variables.
Results:
Of 327 patients, nearly half (48.0%, n = 157) had persistent VPC asthma. Comorbidities and asthma triggers were more frequent in patients with persistent VPC asthma than in patients without VPC asthma. Total geometric mean IgE was higher in patients with persistent VPC asthma (89.3 IU/mL vs 55.7 IU/mL); there was no difference in eosinophil levels. Lung function was lower in patients with persistent VPC asthma (mean % predicted pre- and postbronchodilator FEV1, 63.0% vs 82.8% and 69.6% vs 87.2%, respectively). Exacerbations in the previous year were more likely in patients with persistent VPC asthma (29.7% vs 9.0%, respectively). Predictors of persistent VPC asthma were black versus white race/ethnicity, allergic trigger count (4 vs 0), systemic corticosteroid use, and postbronchodilator FEV1 (per 10% decrease).
Conclusions:
The burden of persistent VPC asthma is high in severe/difficult-to-treat disease; management of modifiable risk factors, maximization of lung function, and trigger avoidance may improve outcomes.
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