title: Effectiveness of cardiac rehabilitation among older patients after acute myocardial infarction.
abstract: BACKGROUND
  Guidelines recommend cardiac rehabilitation after acute myocardial infarction, yet little is known about the impact of cardiac rehabilitation on medication adherence and clinical outcomes among contemporary older adults. The optimal number of cardiac rehabilitation sessions is not clear.
  
  
  METHODS
  We linked patients 65years or older enrolled in the Acute Coronary Treatment Intervention Outcomes Network Registry-Get With the Guidelines (ACTION Registry-GWTG) from January 2007 to December 2010 to Medicare longitudinal claims data to obtain 1 year follow-up.
  
  
  RESULTS
  A total of 11,862 patients participated in cardiac rehabilitation after acute myocardial infarction, attending a median number of 26 sessions. Patients attending ≥26 sessions were more likely to be male, had lesser prevalence of comorbid conditions and prior revascularization, and were more likely to present with ST-segment elevation myocardial infarction, compared with patients attending 1 to 25 sessions. Among patients with Medicare Part D prescription coverage, increasing number of cardiac rehabilitation sessions was associated with improvement in adherence to secondary prevention medications such as P2Y12 inhibitors and β-blockers. Each 5-session increase in participation was associated with lower mortality (adjusted hazard ratio [HR] 0.87, 95% CI 0.83-0.92) and lower overall risk of major adverse cardiac event (adjusted HR 0.69, 95% CI 0.65-0.73) and death/readmission (adjusted HR 0.79, 95% CI 0.76-0.83).
  
  
  CONCLUSIONS
  In this older patient population, number of cardiac rehabilitation sessions attended was associated with improved medication adherence and lower downstream cardiovascular risk in a dose-response relationship. This provides support for the continued use of cardiac rehabilitation for older adults and encourages efforts to maximize attendance.
authors.affiliation: Duke Clinical Research Institute, Durham, NC; Department of Medicine, Duke University, Durham, NC. Electronic address: jacob.doll@duke.edu.
authors.forename: Jacob A
authors.initials: JA
authors.lastname: Doll
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Anne
authors.initials: A
authors.lastname: Hellkamp
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Laine
authors.initials: L
authors.lastname: Thomas
authors.affiliation: VA Eastern Colorado Health Care System, Aurora, CO; University of Colorado School of Medicine, Aurora, CO.
authors.forename: P Michael
authors.initials: PM
authors.lastname: Ho
authors.affiliation: Virginia Commonwealth University, Richmond, VA.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Kontos
authors.affiliation: San Francisco Veterans Affairs Medical Center, San Francisco, CA; University of California, San Francisco, San Francisco, CA.
authors.forename: Mary A
authors.initials: MA
authors.lastname: Whooley
authors.affiliation: Spectrum Health, Grand Rapids, MI.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Boyden
authors.affiliation: Duke Clinical Research Institute, Durham, NC; Department of Medicine, Duke University, Durham, NC.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Peterson
authors.affiliation: Duke Clinical Research Institute, Durham, NC; Department of Medicine, Duke University, Durham, NC.
authors.forename: Tracy Y
authors.initials: TY
authors.lastname: Wang
mesh_terms: D000368:Aged; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000401:mortality / Q000534:rehabilitation*; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D014481:United States / Q000453:epidemiology