title: The new "intermediate risk" group: a comparative analysis of the new 2013 ACC/AHA risk assessment guidelines versus prior guidelines in men.
abstract: BACKGROUND
  The 2013 ACC/AHA Report on the Assessment of Cardiovascular (CVD) Risk redefined "intermediate risk". We sought to critically compare the intermediate risk groups identified by prior guidelines and the new ACC/AHA guidelines.
  
  
  METHODS
  We analyzed data from 30,005 adult men free of known CVD from a large, multi-ethnic study of middle-aged adults. The Framingham Risk Score was calculated using published equations, and CVD risk was calculated using the new ACC/AHA Pooled Cohort Equations Risk Estimator. We first compared the size and characteristics of the intermediate risk group identified by the old (ATP III, 10-20% 10-year CHD risk) and new guidelines (5-7.4% 10-year CVD risk). We then defined time-to-high-risk as the length of time an individual patient resides in the intermediate risk group before progressing to high risk status based on advancing age alone.
  
  
  RESULTS
  The mean age of the study population was 53 ± 13 years, and 24% were African-American. Patients identified as intermediate risk by the new ACC/AHA Guidelines were younger and more likely to be African-American and have lower risk factor burden (all p < 0.05). The new intermediate risk group was just 37% the size of the traditional ATP III intermediate risk group, while the new high risk group was 103% larger. Under the new guidelines, men remain intermediate risk for an average of just 3 years, compared to 8 years under the prior guidelines (63% shorter time-to-high-risk, p < 0.05), before progressing to high risk based on advancing age alone.
  
  
  CONCLUSIONS
  The new 2013 ACC/AHA risk assessment guidelines produce a markedly smaller, lower absolute risk, and more temporary "intermediate risk" group. These findings reshape the modern understanding of "intermediate risk", and have distinct implications for risk assessment, clinical decision making, and pharmacotherapy in primary prevention.
authors.affiliation: Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, Baltimore, MD, USA. Electronic address: mblaha1@jhmi.edu.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Blaha
authors.affiliation: Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, Baltimore, MD, USA.
authors.forename: Zeina A
authors.initials: ZA
authors.lastname: Dardari
authors.affiliation: Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, Baltimore, MD, USA.
authors.forename: Roger S
authors.initials: RS
authors.lastname: Blumenthal
authors.affiliation: Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, Baltimore, MD, USA.
authors.forename: Seth S
authors.initials: SS
authors.lastname: Martin
authors.affiliation: Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, Baltimore, MD, USA; Center for Prevention and Wellness Research, Baptist Health Medical Group, Miami Beach, FL, USA.
authors.forename: Khurram
authors.initials: K
authors.lastname: Nasir
authors.affiliation: Henry Ford Health System, Detroit, MI, USA; King Abdul-Aziz Cardiac Center, Riyadh, Saudi Arabia.
authors.forename: Mouaz H
authors.initials: MH
authors.lastname: Al-Mallah
mesh_terms: D000368:Aged; D000572:American Heart Association; D002309:Cardiology / Q000592:standards*; D002318:Cardiovascular Diseases / Q000175:diagnosis* / Q000453:epidemiology; D015331:Cohort Studies; D018450:Disease Progression; D057286:Electronic Health Records; D006801:Humans; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D018570:Risk Assessment; D012307:Risk Factors; D014481:United States
keywords: Guidelines; Primary prevention; Risk prediction