title: Impact of medication nonadherence on hospitalizations and mortality in heart failure.
abstract: BACKGROUND
  Limited literature exists on the association between medication adherence and outcomes among patients with heart failure.
  
  
  RESULTS
  We conducted a retrospective longitudinal cohort study of 557 patients with heart failure with reduced ejection fraction (HFrEF) (defined by EF <50%) in a large health maintenance organization. We used multivariable Cox proportional hazards models to assess the relationship between adherence (with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, β-blockers, and aldosterone antagonists) and the primary outcome of all-cause mortality plus cardiovascular hospitalizations. Mean follow-up time was 1.1 years. Nonadherence (defined as <80% adherence) was associated with a statistically significant increase in the primary outcome in the cohort overall (hazard ratio 2.07, 95% confidence interval 1.62-2.64; P < .0001). This association remained significant when all 3 classes of heart failure medications and the components of the composite end point were considered separately and when the adherence threshold was varied to 70% or 90%.
  
  
  CONCLUSIONS
  Medication nonadherence was associated with an increased risk of all-cause mortality and cardiovascular hospitalizations in a community heart failure population. Further research is needed to define systems of care that optimize adherence among patients with heart failure.
authors.affiliation: Division of Cardiology, Denver VA Medical Center, Denver, Colorado, USA. ashley.fitzgerald@ucdenver.edu
authors.forename: Ashley A
authors.initials: AA
authors.lastname: Fitzgerald
authors.forename: J David
authors.initials: JD
authors.lastname: Powers
authors.forename: P Michael
authors.initials: PM
authors.lastname: Ho
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Maddox
authors.forename: Pamela N
authors.initials: PN
authors.lastname: Peterson
authors.forename: Larry A
authors.initials: LA
authors.lastname: Allen
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Masoudi
authors.forename: David J
authors.initials: DJ
authors.lastname: Magid
authors.forename: Edward P
authors.initials: EP
authors.lastname: Havranek
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000401:mortality* / Q000628:therapy*; D006760:Hospitalization / Q000639:trends*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D055815:Young Adult