Primary Prevention of Coronary Heart Disease Aryan Mooss, M.D., F.A.C.C.
Faculty Disclosure Aryan Mooss, MD Dr. Mooss has listed an affiliation with: Grant/Research Support- Medtronic Speakers Bureau- Novartis however, no conflict of interest exists for this conference.
Objectives • Briefly review current approaches to primary prevention • Discuss the limitations of the Framingham Risk Assessment models • Review the evidence base for earlier and more aggressive treatment of hypercholesterolemia
The fundamental principle in primary prevention of Coronary Heart Disease is the identification of individuals with coronary risk factors and modify those risk factors
Four Basic Categories of Risk Factors Braunwald, 7th edition page 1058
Cumulative incidence of CVD adjusted for the competing risk of death for men and women according to aggregate risk factor (RF) burden at 50 years of age IDEAL RISK FACTOR PROFILE BP 120/80 CHOL <180 NONSMOKER NON DIABETIC Lloyd-Jones, D. M. et al. Circulation 2006;113:791-798
Change in age-adjusted mortality from coronary heart disease (CHD), stroke, and non-CVD in the United States, 1950 to 2002. National Heart, Lung, and Blood Institute: Morbidity and Mortality: 2004 Chart Book on Cardiovascular, Lung, and Blood Diseases. Bethesda, MD, National Heart, Lung, and Blood Institute, 2004, p 23
Temporal Changes in Coronary Risk Factors The Practice of Coronary Disease Prevention, 1996, p. 3
2007 UpdateHeart Disease and Stroke Statistics • Deaths from Cardiovascular Diseases in USA 871,517 (36% all deaths) • Deaths (worldwide) 17.5 million • Acute Coronary Syndrome 1,500,000 • Coronary Heart Disease 15,800,000
Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults JAMA. 2001;285:2486-2497.
Limitations of Present Guidelines • Family history is not included in the Framingham Risk Estimate In a recent study of 784 siblings (age 30-59) of patients hospitalized with CAD <60 years age and followed for 10 years, the incidence of CAD events was 20% as opposed to the Framingham estimate of 12% Vardya, et al, Amer J Card 2007
Limitations of Framingham Risk Estimate (continued) • Age and gender are the predominant factors in risk estimate • Life time risk estimate may be more relevant than 10 year estimate • Guidelines emphasize coronary event reduction rather than preventing atherosclerosis
30 year old obese female • 2 pack a day smoker • Cholesterol – 240 • HDL – 35 • BP 160 systolic • FRS (10 year risk) 8%
Arguments in favor of aggressive LDL lowering irrespective of baseline risk
How Low and How Long? 2 mutations of the gene coding for the serine protease PCSK9 results in 28% and 15% reduction in LDL levels and 50-88% reduction in coronary events Cohen, etal NEJM 2006
Conclusions • Substantial progress has been made in primary prevention of CHD, however, we still have a long way to go • Current primary prevention strategies are useful to some degree but, have important limitations • Aggressive cholesterol lowering approaches are theoretically attractive, but clinical trial data in primary prevention is lacking