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(*)) 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 beta(2)-agonist (LABA), and higher dose ICS/LABA plus short-acting beta(2)-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 (>or=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.
Division of Pulmonology, Department of Medicine, University of Cape Town, Cape Town, South Africa. Eric.Bateman@uct.ac.za
Eric D
ED
Bateman
Helen K
HK
Reddel
Göran
G
Eriksson
Stefan
S
Peterson
Ollie
O
Ostlund
Malcolm R
MR
Sears
Christine
C
Jenkins
Marc
M
Humbert
Roland
R
Buhl
Tim W
TW
Harrison
Santiago
S
Quirce
Paul M
PM
O'Byrne
D000280:Administration, Inhalation; D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage*; D001249:Asthma / Q000628:therapy*; D019819:Budesonide / Q000008:administration & dosage* / Q000627:therapeutic use; D000069502:Budesonide, Formoterol Fumarate Drug Combination; D002648:Child; D002675:Child, Preschool; D004338:Drug Combinations; D004983:Ethanolamines / Q000008:administration & dosage* / Q000627:therapeutic use; D005260:Female; D000068759:Formoterol Fumarate; D006801:Humans; D008297:Male; D008390:Markov Chains; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D055815:Young Adult
D000305:Adrenal Cortex Hormones; D000318:Adrenergic beta-Agonists; D018927:Anti-Asthmatic Agents; D000069502:Budesonide, Formoterol Fumarate Drug Combination; D004338:Drug Combinations; D004983:Ethanolamines; D019819:Budesonide; D000068759:Formoterol Fumarate