Determinants of future long-term asthma control

Abstract

Background: Asthma control has been hypothesized to be inversely related to asthma severity, directly related to effective management, and also related to other definable factors, but empiric data to support this construct are few.

Objective: We sought to identify independent prospective determinants of future long-term asthma control among asthma severity, management, demographic, and comorbidity predictors.

Methods: Surveys were completed by a random sample of 2250 health maintenance organization members aged 18 to 56 years with persistent asthma. Linked computerized pharmacy data provided baseline and follow-up year medication dispensings. The outcome was follow-up year long-term asthma control, as assessed by using a previously validated 4-level scale based on the number of short-acting beta-agonist canister dispensings.

Results: Oral corticosteroids (odds ratio [OR], 1.9) or unscheduled visits (OR, 1.2) in the prior year, any prior asthma hospitalizations (OR, 1.4), smoking (OR, 2.2), chronic obstructive pulmonary disease (OR, 1.9), male sex (OR, 1.5), black race (OR, 1.3), and lower educational level (OR, 1.1) were independently associated with poorer control in ordinal logistic regression analyses. Regular inhaled corticosteroids (OR, 0.7), long-acting beta-agonists (OR, 0.7) and asthma specialist care (OR, 0.6) were independently associated with better control.

Conclusions: Markers of asthma severity and other patient characteristics are inversely related to future asthma control, but effective management strategies are associated with improved asthma control, even after accounting for these high-risk characteristics.

Clinical implications: Inhaled corticosteroids, long-acting beta-agonists, and asthma specialist care are associated with improved asthma control, even after accounting for markers of asthma severity.