Cardiovascular Disease Risk Prediction - Integration into Clinical Practice

Keywords Riskprediction .Atherosclerosis .CoronaryarterydiseaseIntroductionAnestimated83.6millionAmericanadultshaveatherosclerot-ic cardiovascular vascular disease (CVD) and one in everythreedeathsintheUnitesStatesisattributedtoCVD.Coronaryheartdisease(CHD)alonecausedaboutoneofeverysixdeathsin the US in 2008. More than half of patients who present assudden cardiac death have no antecedent symptoms [1].Risk assessment and stratification of asymptomatic adultsare essential parts of CVD preventive strategies [2]. Interven-tions usually have the same relative-risk reduction acrossdifferent risk strata. The highest absolute-risk reduction willoccur for individuals with the highest pre-treatment risk. Ac-cordingly, determination of absolute risk is crucial to ade-quately assess the risk-benefit ratio.The absolute risk of a cardiovascular event can be estimat-ed from the presence or absence of certain risk factors (RFs).Those RFs usually coexist and interact with each other. Mildelevation in multiple RFs has much more effect on absoluteriskthanasubstantialelevationofasingleRF.Inotherwords,an integrated risk calculation is a much better predictor offuture vascular events than any single RF [3–5]. Without aformal way to assess CVD risk, both patients and physicianstend to overestimate or underestimate the actual risk [6–8].These facts highlight the importance of having formalmethods for CVD risk prediction usually using some kind ofrisk assessment score or calculator. Every major guideline forthe prevention of CVD stresses risk assessment as the initialapproach in evaluating a patient [9–12].In this article, we briefly summarize the most commonlyused CVD risk assessment methods. We highlight eachmethod’s strengths and weaknesses and provide an updatedreview on the current role of lifetime risk calculations. Be-causeofincreasingliteratureofcoronaryarterycalcium(CAC) as a measure of atherosclerosis, we review recentstudies of its role in risk evaluation. Finally, we evaluate thebest ways to incorporate current risk assessment scores intoclinical practice.Current CVD Risk ScoresThere are many CVD risk prediction models available toclinicians. Table 1 summarizes key features of the most com-monly used CVD risk scores. The Framingham Risk Score(FRS) is a landmark achievement [13]. The version used in2001 Adult Treatment Panel III (ATP III) estimates 10-yearrisk of development of “hard” CHD. In 2008, the FRS forglobal CVD was developed to predict all major CVD out-comes (Table 1)[14]. Thirty-years [15] and lifetime [16]riskmodels have also been developed from the Framingham co-hort.Reynoldsriskscoreuseshigh-sensitivityC-reactivepro-tein (hs-CRP) and parental history of myocardial infarctionprior to age 60 years with the traditional Framingham RFs.Similarly, multiple risk scores have been derived from Euro-peancohortsincludingtheASSIGN[17],SCORE[5],QRISK[18] and PROCAM [19] scores (Table 1).Limitations of Currently Available Risk ScoresRiskscoreshaveseveralwellacknowledgedlimitations.First,becausemostsubjectswithhighriskburden(≥1RFs)willnotdevelop CVD over the following 10-year period, risk scores