Evaluation of asthma prescription measures and health system performance based on emergency department utilization.

BACKGROUND: Measures based on the use of either antiinflammatory and/or reliever medications have been used to evaluate clinical performance in asthma.

OBJECTIVE: We compared the association between 2 asthma prescription measures (APMs) and subsequent risk of emergency department (ED) asthma visits.

DESIGN: We conducted a cross-sectional analysis of automated pharmacy and healthcare utilization data from 3 large geographically diverse managed care organizations.

PARTICIPANTS: We studied children, 3 to 15 years of age, with at least 1 encounter for asthma (hospitalization, ED, or ambulatory care), at least 1 dispensing of an asthma medication, and continuous enrollment between June 1996 and July 1997.

MEASURES: Two performance measures were derived for patients with persistent asthma: 1) the proportion of individuals who have received controller therapy and 2) the ratio of dispensed controller to dispensed reliever medications. Children with persistent asthma were identified using the Health Employers Data Information System (HEDIS) criteria of the National Committee on Quality Assurance definition. Multivariate logistic regression was used to assess independent effects in models for ED visits.

RESULTS: Among children with persistent asthma, the dispensing of a controller was associated with a significantly lower risk of an ED visit as compared with children not dispensed a controller (odds ratio, 0.3; 95% confidence interval, 0.2-0.4). An association between the ratio of controller to reliever dispensing and the risk of subsequent ED visit was also observed, however, the underlying level of reliever dispensing modified the relationship. Among children with persistent asthma, the ratio of controller to reliever dispensing was inversely associated with risk of ED visit among children dispensed <4 relievers/person-year but no significant relationship was seen among children dispensed > or =4 relievers/person-year.

CONCLUSION: Among children with persistent asthma, the use of an asthma prescription measure (APM) can help stratify children based on their risk of future adverse events. The HEDIS measure, the dispensing of a controller medication among a population with persistent asthma, and the controller to reliever ratio are associated with the risk of subsequent ED visit. However, the association between the ratio measure and risk for ED visit is modified by the underlying level of reliever dispensing.