Asthma morbidity among inner-city adolescents receiving guidelines-based therapy: role of predictors in the setting of high adherence.
BACKGROUND
With the expanding effort to provide guidelines-based therapy to adolescents with asthma, attention must be directed to evaluating which factors predict future asthma control when guidelines-based management is applied.


OBJECTIVE
We evaluated the role of fraction of exhaled nitric oxide in parts per billion, markers of allergic sensitization, airway inflammation, and measures of asthma severity in determining future risk of asthma symptoms and exacerbations in adolescents and young adults participating in the Asthma Control Evaluation study.


METHODS
Five hundred forty-six inner-city residents, ages 12 through 20 years, with persistent asthma were extensively evaluated at study entry for predictors of future symptoms and exacerbations over the subsequent 46 weeks, during which guidelines-based, optimal asthma management was offered. Baseline measurements included fraction of exhaled nitric oxide in parts per billion, total IgE, allergen-specific IgE, allergen skin test reactivity, asthma symptoms, lung function, peripheral blood eosinophils, and, for a subset, airway hyperresponsiveness and sputum eosinophils.


RESULTS
The baseline characteristics we examined accounted for only a small portion of the variance for future maximum symptom days and exacerbations--11.4% and 12.6%, respectively. Future exacerbations were somewhat predicted by asthma symptoms, albuterol use, previous exacerbations, and lung function, whereas maximum symptom days were predicted, also to a modest extent, by symptoms, albuterol use, and previous exacerbations, but not lung function.


CONCLUSIONS
Our findings demonstrate that the usual predictors of future disease activity have little predictive power when applied to a highly adherent population with persistent asthma that is receiving guidelines-based care. Thus, new predictors need to be identified that will be able to measure the continued fluctuation of disease that persists in highly adherent, well-treated populations such as the one studied.
Gruchalla
Rebecca S
RS
University of Texas Southwestern Medical Center, Dallas, Tex 75390-8859, USA. Rebecca.Gruchalla@utsouthwestern.edu
Sampson
Hugh A
HA
Matsui
Elizabeth
E
David
Gloria
G
Gergen
Peter J
PJ
Calatroni
Agustin
A
Brown
Mark
M
Liu
Andrew H
AH
Bloomberg
Gordon R
GR
Chmiel
James F
JF
Kumar
Rajesh
R
Lamm
Carin
C
Smartt
Ernestine
E
Sorkness
Christine A
CA
Steinbach
Suzanne F
SF
Stone
Kelly D
KD
Szefler
Stanley J
SJ
Busse
William W
WW
D000085:Acetates / Q000627:therapeutic use; D000293:Adolescent; D000318:Adrenergic beta-Agonists / Q000627:therapeutic use; D000420:Albuterol / Q000031:analogs & derivatives / Q000627:therapeutic use; D000485:Allergens / Q000276:immunology; D000730:Androstadienes / Q000627:therapeutic use; D018927:Anti-Asthmatic Agents / Q000627:therapeutic use; D001249:Asthma / Q000188:drug therapy* / Q000453:epidemiology*; D015415:Biomarkers / Q000032:analysis; D002648:Child; D003521:Cyclopropanes; D004311:Double-Blind Method; D045853:Exhalation / Q000502:physiology; D005260:Female; D000068298:Fluticasone; D005500:Follow-Up Studies; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D009569:Nitric Oxide / Q000032:analysis; D010349:Patient Compliance; D017410:Practice Guidelines as Topic; D011804:Quinolines / Q000627:therapeutic use; D000068299:Salmeterol Xinafoate; D012882:Skin Tests; D013440:Sulfides; D014505:Urban Population; D055815:Young Adult
D000085:Acetates; D000318:Adrenergic beta-Agonists; D000485:Allergens; D000730:Androstadienes; D018927:Anti-Asthmatic Agents; D015415:Biomarkers; D003521:Cyclopropanes; D011804:Quinolines; D013440:Sulfides; D009569:Nitric Oxide; D007073:Immunoglobulin E; D000068299:Salmeterol Xinafoate; D000068298:Fluticasone; C093875:montelukast; D000420:Albuterol