Risk Factors for Asthma Exacerbation and Treatment Failure in Adults and Adolescents with Well-Controlled Asthma during Continuation and Step Down Therapy.
Ann Am Thorac Soc. 2018 Jun 04;:
Authors: DiMango E, Rogers L, Reibman J, Gerald LB, Brown M, Sugar EA, Henderson R, Holbrook JT
RATIONALE: Although national and international guidelines recommend reduction of asthma controller therapy or 'step-down" therapy in patients with well controlled asthma, it is expected that some individuals may experience worsening of asthma symptoms or asthma exacerbations during step-down. Characteristics associated with subsequent exacerbations during step-down therapy have not been well defined. The effect of environmental tobacco smoke (ETS) exposure on risk of treatment failure during asthma step down therapy has not been reported.
OBJECTIVES: To identify baseline characteristics associated with treatment failure and asthma exacerbation during maintenance and guideline-based step-down therapy.
METHODS: The present analysis uses data collected from a completed randomized controlled trial of optimal step-down therapy in patients with well controlled asthma taking moderate dose combination inhaled corticosteroids/long acting beta agonists. Participants were 12 years or older with physician diagnosed asthma and were enrolled between December 2011 and May 2014.
RESULTS: An Emergency Room visit in the previous year was predictive of a subsequent treatment failure (HR 1.53 (1.06, 2.21 CI). For every 10% increase in baseline forced expiratory volume in one second percent predicted, the hazard for treatment failure was reduced by 14% (95% CI: 0.74-0.99). There was no difference in risk of treatment failure between adults and children, nor did duration of asthma increase risk of treatment failure. Age of asthma onset was not associated with increased risk of treatment failure. Unexpected emergency room visit in the previous year was the only risk factor significantly associated with subsequent asthma exacerbations requiring systemic corticosteroids. Time to treatment failure or exacerbation did not differ in participants with and without self-report of ETS exposure.
CONCLUSIONS: The present findings can help clinicians identify patients more likely to develop treatment failures and exacerbations and who may therefore require closer monitoring during asthma step-down treatment. Individuals with reduced pulmonary function, a history of exacerbations, and early onset disease, even if otherwise well controlled, may require closer observation to prevent treatment failures and asthma exacerbations. Clinical trial registered with ClinicalTrials.gov (NCT01437995).
PMID: 29863899 [PubMed - as supplied by publisher]