Relationship between recent short-acting beta-agonist use and subsequent asthma exacerbations.
BACKGROUND
US national guidelines recommend assessing short-acting beta-agonist (SABA) medication use as a marker of asthma severity and control. However, the relationship between recent SABA use and asthma exacerbations is not currently known.


OBJECTIVE
To evaluate the proximal relationship between the type and frequency of SABA use and asthma-related outcomes.


METHODS
We evaluated SABA use among patients with asthma ages 5 to 56 years who were members of a large health maintenance organization in southeast Michigan. Frequency of use was estimated from pharmacy data assessing the timing and amount of SABA fills. Cox proportional hazards models were used to examine the prospective relationship between average daily SABA use for 3 months and outcomes associated with poor asthma control (ie, oral corticosteroids use, asthma-related emergency department visits, and asthma-related hospitalizations). We separately accounted for SABA metered-dose inhaler (MDI) and SABA nebulizer use.


RESULTS
Of the 2,056 patients who met study criteria, 1,569 (76.3%) had used a SABA medication in their baseline year. After adjusting for potential confounders, SABA nebulizer use was associated with asthma-related emergency department visits (adjusted hazard ratio [aHR], 6.32; 95% confidence interval [CI], 2.38 to 16.80) and asthma-related hospitalizations (aHR, 21.62; 95% CI, 3.17 to 147.57). In contrast, frequency of SABA MDI use was not associated with these outcomes.


CONCLUSIONS
Frequency of SABA use during a 3-month period was associated with poor asthma outcomes. The relationship with poor asthma outcomes was strongest for SABA nebulizer use, suggesting that the type of SABA used is also of prognostic importance.
Paris
Jason
J
Department of Internal Medicine, Henry Ford Hospital, Detroit, Michigan 48202, USA.
Peterson
Edward L
EL
Wells
Karen
K
Pladevall
Manel
M
Burchard
Esteban G
EG
Choudhry
Shweta
S
Lanfear
David E
DE
Williams
L Keoki
LK
D000293:Adolescent; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage* / Q000009:adverse effects; D000328:Adult; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D036501:Metered Dose Inhalers; D008875:Middle Aged; D009330:Nebulizers and Vaporizers; D016016:Proportional Hazards Models; D011446:Prospective Studies; D016896:Treatment Outcome; D055815:Young Adult
D000318:Adrenergic beta-Agonists; D018927:Anti-Asthmatic Agents