title: Effects of changing guidelines on prescribing aspirin for primary prevention of cardiovascular events.
abstract: OBJECTIVE
  The use of low-dose aspirin for primary prevention of cardiovascular events in patients at elevated risk for cardiovascular disease (CVD) is increasingly being questioned. Aspirin may not benefit this population and may increase the risk of major bleeding events. Data support aspirin use in patients with known CVD.
  
  
  METHODS
  This is a secondary analysis of de-identified electronic health record (EHR) data from 131,050 individuals with known CVD or elevated risk for CVD as determined by diagnostic, demographic, and clinical data collected from 33 primary care practices in 11 different clinical organizations across 6 states. The percentage of the population of each cohort with aspirin recorded on their medication list, created through risk base analysis, was observed across 4 time periods.
  
  
  RESULTS
  From 2007 to 2011, aspirin usage reflected in the EHR increased for the entire population and for each individual high-risk diagnosis. The percentage of the population initiating aspirin therapy for primary prevention within a year of diagnosis of CVD risk factors or CVD "equivalency" increased between 2007 and 2011. Among those with a new diagnosis of CVD, aspirin usage also steadily increased over the 4-year period, indicating no negative impact from new negative primary prevention studies.
  
  
  CONCLUSIONS
  Primary care clinicians have a central role in providing evidence-based preventive services and should integrate revised information into their practice to improve outcomes. Even with new evidence against the use of aspirin for primary prevention, it is difficult to change beliefs about the effectiveness and safety of aspirin, as reflected in the behavior of physicians and patients.
authors.affiliation: the Louisiana State University Emergency Medicine Residency, New Orleans; the Exempla St. Joseph Hospital Internal Medicine Residency, Denver, CO; and the Department of Family Medicine, University of Colorado School of Medicine, Aurora.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Hissett
authors.forename: Brittany
authors.initials: B
authors.lastname: Folks
authors.forename: Letoynia
authors.initials: L
authors.lastname: Coombs
authors.forename: William
authors.initials: W
authors.lastname: Leblanc
authors.forename: Wilson D
authors.initials: WD
authors.lastname: Pace
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001241:Aspirin / Q000627:therapeutic use*; D002318:Cardiovascular Diseases / Q000517:prevention & control*; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D010818:Practice Patterns, Physicians' / Q000639:trends*; D011320:Primary Health Care / Q000639:trends*; D012189:Retrospective Studies
chemical_list: D010975:Platelet Aggregation Inhibitors; D001241:Aspirin
keywords: Aspirin; Cardiovascular Diseases; Primary Prevention