Longitudinal association between medication adherence and lung health in people with cystic fibrosis

J Cyst Fibros. 2011 Jul;10(4):258-64. doi: 10.1016/j.jcf.2011.03.005. Epub 2011 Mar 31.


Background: This study examined the relationship of medication adherence to frequency of pulmonary exacerbation and rate of decline in FEV(1)% predicted (FEV(1)).

Methods: 95 CF patients aged 6 years or older and prescribed a pulmonary medication, were enrolled in a longitudinal retrospective review of medication adherence and health outcomes (the occurrence and frequency of intravenous (IV) antibiotic treatments and FEV(1)) over 12-months. Pharmacy refill records were used to calculate a medication possession ratio (MPR).

Results: Composite MPR predicted the occurrence of at least one pulmonary exacerbation requiring a course of IV antibiotics (IRR=2.34, p=0.05), but not the frequency of exacerbations, after controlling for gender, baseline FEV(1,) and regimen complexity. Composite MPR predicted baseline FEV(1) (estimate=29.81, p=.007), but not decline in FEV(1).

Conclusions: These results demonstrate a significant relation between medication adherence and IV antibiotics in CF patients, highlighting the importance of addressing adherence during clinic visits to improve health outcomes.

MeSH terms

  • Adolescent
  • Anti-Bacterial Agents / administration & dosage*
  • Azithromycin / administration & dosage
  • Child
  • Cystic Fibrosis / drug therapy*
  • Cystic Fibrosis / physiopathology
  • Deoxyribonuclease I / administration & dosage*
  • Drug Prescriptions / statistics & numerical data
  • Female
  • Forced Expiratory Volume / drug effects
  • Humans
  • Infusions, Intravenous
  • Longitudinal Studies
  • Male
  • Medication Adherence / statistics & numerical data*
  • Outcome Assessment, Health Care
  • Pharmacy / statistics & numerical data
  • Retrospective Studies
  • Tobramycin / administration & dosage*
  • Young Adult


  • Anti-Bacterial Agents
  • Azithromycin
  • DNASE1 protein, human
  • Deoxyribonuclease I
  • Tobramycin