Treatment patterns among adult patients with asthma: factors associated with overuse of inhaled beta-agonists and underuse of inhaled corticosteroids.
BACKGROUND
Overuse of inhaled beta-agonists and underuse of inhaled corticosteroids by patients with asthma may have adverse consequences. This study was performed to identify factors associated with misuse of these types of asthma medication.


METHODS
We examined baseline data from a longitudinal survey of adult patients with asthma. The setting was a consortium of 15 national managed care organizations serving 11 large employers. Baseline surveys were completed by 6612 health plan enrollees at least 18 years old who had had at least 2 visits with a diagnostic code for asthma in the preceding 2 years. The main outcome measures were the overuse of inhaled beta-agonists and the underuse of inhaled corticosteroids. Independent variables were patient and process of care factors.


RESULTS
Among patients with moderate or severe asthma, 16% of users of inhaled beta-agonists reported overuse (>8 puffs per day on days of use), and 64% of users of inhaled corticosteroids reported underuse (use on < or =4 days/wk or < or =4 puffs per day). Overuse of inhaled beta-agonists was most strongly associated with concomitant treatment with inhaled corticosteroids or anticholinergic agents, increased asthma symptom severity, problems in obtaining asthma medication, and male sex. Underuse of inhaled corticosteroids was associated with nonwhite race, younger age (18 to 34 years), lower use of inhaled beta-agonist, lower symptom severity, and not possessing a peak flow meter. Rates of misuse of medication also varied by speciality of the patient's provider (generalist, allergist, or pulmonologist).


CONCLUSIONS
Overuse of inhaled beta-agonists may be caused by symptom severity, while underusers of corticosteroids may interrupt use as symptoms abate. This study demonstrated an important opportunity to improve medication use among patients with asthma.
Diette
G B
GB
Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21287, USA. gdiette@welch.jhu.edu
Wu
A W
AW
Skinner
E A
EA
Markson
L
L
Clark
R D
RD
McDonald
R C
RC
Healy
J P
JP
Huber
M
M
Steinwachs
D M
DM
D000280:Administration, Inhalation; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage*; D000328:Adult; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage*; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage*; D001249:Asthma / Q000188:drug therapy*; D015331:Cohort Studies; D004334:Drug Administration Schedule; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008329:Managed Care Programs / Q000706:statistics & numerical data; D015999:Multivariate Analysis; D009330:Nebulizers and Vaporizers; D010349:Patient Compliance; D013256:Steroids
D000318:Adrenergic beta-Agonists; D018927:Anti-Asthmatic Agents; D000893:Anti-Inflammatory Agents; D013256:Steroids