Overall asthma control: The relationship between current control and future risk

Background: Asthma guidelines emphasize both maintaining current control and reducing future risk, but the relationship between these 2 targets is not well understood. Objective: This retrospective analysis of 5 budesonide/formoterol maintenance and reliever therapy (Symbicort SMART Turbuhaler**Symbicort SMART and Turbuhaler are trademarks owned by AstraZeneca. Neither the Symbicort SMART posology nor the dry powder formulation Turbuhaler are currently approved in the United States.) studies assessed the relationship between asthma control questionnaire (ACQ-5) and Global Initiative for Asthma-defined clinical asthma control and future risk of instability and exacerbations. Methods: The percentage of patients with Global Initiative for Asthma-defined controlled asthma over time was assessed for budesonide/formoterol maintenance and reliever therapy versus the 3 maintenance therapies; higher dose inhaled corticosteroid (ICS), same dose ICS/long-acting β2-agonist (LABA), and higher dose ICS/LABA plus short-acting β2-agonist. The relationship between baseline ACQ-5 and exacerbations was investigated. A Markov analysis examined the transitional probability of change in control status throughout the studies. Results: The percentage of patients achieving asthma control increased with time, irrespective of treatment; the percentage Controlled/Partly Controlled at study end was at least similar to budesonide/formoterol maintenance and reliever therapy versus the 3 maintenance therapies: higher dose ICS (56% vs 45%), same dose ICS/LABA (56% vs 53%), and higher dose ICS/LABA (54% vs 54%). Baseline ACQ-5 score correlated positively with exacerbation rates. A Controlled or Partly Controlled week predicted at least Partly Controlled asthma the following week (≥80% probability). The better the control, the lower the risk of an Uncontrolled week. The probability of an exacerbation was related to current state and was lower with budesonide/formoterol maintenance and reliever therapy. Conclusions: Current control predicts future risk of instability and exacerbations. Budesonide/formoterol maintenance and reliever therapy reduces exacerbations versus comparators and achieves at least similar control. © 2010 American Academy of Allergy, Asthma & Immunology.