Medication compliance and disease exacerbation in patients with asthma: a retrospective study of managed care data

Ann Allergy Asthma Immunol. 2006 Sep;97(3):402-8. doi: 10.1016/S1081-1206(10)60808-3.


Background: Compliance with asthma medications probably results in improved outcomes, but few studies have examined this relationship.

Objective: To examine the association between medication compliance and exacerbation in asthmatic patients.

Methods: Retrospective analysis of a managed care database. The 97,743 participants (aged 6-99 years; mean age, 32.8 years) had asthma and prescriptions for controller medications. Compliance with the index medication (the first controller medication prescribed) was measured using 2 methods: medication possession ratio (MPR), calculated for 365 days after the index date, and number of prescriptions for each index medication. Exacerbation was defined as 1 or more emergency department visits or hospitalizations within 1 year of the index date. Multivariate models were used to determine the odds of exacerbation based on relative compliance for each definition of compliance.

Results: Based on the median MPR, more-compliant patients were less likely to experience exacerbation than less-compliant patients (odds ratio, 0.94; 95% confidence interval, 0.91-0.97; P < .001). Using the 75th percentile MPR, risk of exacerbation was even smaller (odds ratio, 0.89; 95% confidence interval, 0.86-0.92; P < .001). All the cutoff points for compliance (> or = 2 through > or = 6 prescriptions) demonstrated significantly less exacerbations in more-compliant vs less-compliant patients after adjusting for covariates. As the criteria for compliance became more stringent, more-compliant patients became increasingly less likely to have an exacerbation vs less-compliant patients.

Conclusion: More-compliant asthmatic patients were significantly less likely to experience exacerbation than less-compliant asthmatic patients. These findings demonstrate the importance of improving medication compliance among asthmatic patients to impact outcomes.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Asthmatic Agents / therapeutic use*
  • Asthma / drug therapy*
  • Asthma / physiopathology*
  • Child
  • Female
  • Humans
  • Male
  • Managed Care Programs / statistics & numerical data
  • Middle Aged
  • Patient Compliance*
  • Retrospective Studies
  • United States


  • Anti-Asthmatic Agents