Primordial prevention is aimed at prevention of the risk factors for CVD, such as efforts aimed to prevent hypertension, obesity, or dyslipidaemia. Primary prevention, which focuses on the modification of these and other known risk factors, is aimed at preventing the clinical manifestations of CVD, such as myocardial infarction and stroke. Secondary prevention focuses on those who already have manifestations of disease, but where aggressive control of risk factors can have a major impact in preventing recurrences of disease. Concerted efforts between governmental agencies, the community, and the private sector are required to best address the continuing epidemic of CVD. 

Preventive strategies can be considered using the ‘ABCDE’ approach addressing aspirin/antiplatelet therapy:

• blood pressure and hypertension

• cholesterol and dyslipidaemia 

• diet and nutrition 

• and exercise and physical activity 

• For secondary prevention among people with pre-existing CVD, guidelines have been published by the AHA/American College of Cardiology [1].

Aspirin and Antiplatelet Therapy 

Aspirin prophylaxis (81–162 mg/day) has been recommended for people at intermediate risk, for the prevention of CHD in men and prevention of stroke in women, including those with diabetes or metabolic syndrome [2]. Additionally, among those with pre-existing CVD, aspirin is recommended in combination with clopidogrel due to the added benefit in prevention of secondary events. The use of alternative antiplatelet therapies is also discussed.

Blood Pressure Control 

The JNC-7 guidelines [3] have recommended the standard blood pressure goal of treatment of those with hyper- tension to be less than 140/90 mmHg, usually starting with a diuretic or beta blocker and considering additional therapy as needed to reach the goal, in most uncomplicated subjects. Recently, however, the American

Diabetes Association modified the target blood pressure to less than 140/80 mmHg for most patients with diabetes (given the results of recent clinical trials such as the blood pressure sub-study in ACCORD that did not demonstrate benefits from lower blood pressure goals in such patients) and continued the recommendation for using an ACE inhibitor or angiotensin receptor blocker as the preferred therapy due to their renal protective effects. The JNC-7 guidelines additionally recommend beginning with combination therapy (including fixed dosage combinations) for people who are 20 mmHg or more systolic or 10 mmHg or more diastolic blood pressure away from the treatment goal. This takes into account the fact that, based on prior trials, for most patients, two or three medications will be needed to achieve adequate blood pressure control. Additionally, both the JNC-7 and AHA note a normal blood pressure optimal for the population to be less than 120/80 mmHg. A more recent report from members appointed to the JNC-8, however, has raised the threshold for treatment and goal to below 150/90 mmHg in adults aged 60 years and over, [4] although this has not been endorsed by other recent guidelines. 

Cholesterol and Lipid Control 

Previous National Cholesterol Education Program (NCEP) goals for treatment of elevated LDL-cholesterol include achieving levels of < 100 mg/dL in those with the highest risk (pre-existing CHD or other CHD risk equivalents such as those with diabetes or other atherosclerotic disease or a calculated global risk of greater than 20 per cent for CHD in 10 years); less than 130 mg/dL in those with two or more risk factors; and <160 mg/dL in those with less than two risk factors (see section on risk assessment). Optional goals for lowering LDL-C to less than 70 mg/dL have been recommended for those at the very highest risk (e.g. pre-existing CVD plus diabetes or other uncontrolled risk factors, or with acute coronary syndromes). The NCEP has also recommended non-HDL-C targets that are 30 mg/dL higher than the respective LDL-C targets for those with triglyceride levels of 200 mg/ dL or greater as such people may have other atherogenic lipoproteins present and/or where the calculation of LDL-C is less accurate. While triglycerides less than 150 mg/dL and HDL-C levels of 40 mg/dL or greater in men and 50 mg/dL or greater in women are considered to be desirable, these are not specific therapeutic tar- gets due to the lack of demonstrated benefit from clinical trials on CVD end points. Statins (HMG-CoA reductase inhibitors) are the preferred first-line therapeutic approach after lifestyle modification, given the strength of the evidence from numerous clinical trials. There are currently no recommendations for the addition of fibrate therapy or niacin given the lack of incremental benefit over statins as shown by recent clinical trials. Most recent American College of Cardiology/ American Heart Association Guidelines for the Management of Blood Cholesterol [5] have revised the approach for management of dyslipidaemia to include four statin eligible groups: 

• those with known atherosclerotic cardiovascular dis- ease, 

• those with LDL-cholesterol of 190 mg/dl or higher, 

• those with diabetes, and 

• those with a 10-year pooled cohort risk of atherosclerotic cardiovascular disease of 7.5 per cent or greater with LDL-C monitoring recommended only for evaluation of therapeutic response and adherence to statin therapy. 

Cigarette Smoking Prevention and Intervention 

Smoking cessation has long been documented to reduce the risk of CVD. The risk of CHD is reduced by 50 per cent within 1 year of smoking cessation and to that of a never-smoker within 15 years. It is recommended that at each consultation with a healthcare provider the visit should be used as an opportunity to address the 5As of smoking cessation counselling which include ‘Ask’ (assess tobacco use at every visit), ‘Advise’ (strongly urge quitting), ‘Attempt’ (try to identify smokers ready to quit), ‘Assist’ (aid the patient in quitting), and ‘Arrange’ (for follow-up contacts). Interventions for smoking are varied. For youth, school, and community-based prevention programmes, state and federal initiatives, as well as cessation assistance are available. For adults, behavioural treatment, self-help approaches, and pharmacological therapy are used, with varying levels of success. For example quit rates vary from 6 per cent with physician advice only to 40 per cent in those who participate in group programmes [6].

Diabetes Control

Recommendations for the treatment of diabetes to optimize cardiovascular risk reduction are available from a variety of sources. For example, the latest recommendations from the American Diabetes Association address antiplatelet therapy, glycaemic control, blood pressure control, lipid control, weight control, and lifestyle management. Moreover, similar guidelines have been published by the European Association for the Study of Diabetes. Multifactorial intervention focusing on lipid, blood pressure, and glycaemic control has been shown to decrease the risk of future CVD events by more than 50 per cent [7]. This is a very important message given that in recent reports, only one tenth of those with diabetes have achieved target treatment levels for HbA1c, blood pressure, and LDL-C [8]. While the goal of glycaemic control is a HbA1c level of less than 7 per cent in most uncomplicated diabetics, and even 6–6.5 per cent if achievable without side effects, given the results of recent trials, HbA1c levels of less than 8 per cent are accepted as an appropriate goal for those with pre-existing micro or macro-vascular disease or difficult-to- control diabetes [9]. For optimal control, the recommended lipid targets from the American Diabetes Association are for the LDL-C to be less than 100 mg/dL (< 70 mg/dL if known macrovascular disease is present) and blood pressure of less than 140/80 mmHg for most people. More recent recommendations from the ACC/AHA have called for statin use in those with diabetes whose LDL-C is at least 70 mg/dL and a high- intensity statin in those who additionally have a 10-year ASCVD risk of 7.5 per cent or greater. Moreover, members appointed to the JNC-8 have recommended a threshold for treatment and goal for blood pressure to be set at 140/90 mmHg [10]

Exercise and Physical Activity 

The ACC/AHA currently recommends 3 to 4 sessions a week, lasting on average 40 minutes per session, and involving moderate- to vigorous-intensity physical activity [11]. Regular physical activity can help maintain healthy blood pressure, weight, lipid levels, low levels of inflammation (C-reactive protein) and insulin sensitivity. A pedometer can be an effective tool for intervention with one guideline, for example, recommending walking at least 10,000 steps a day. For secondary prevention, a prescribed exercise programme is recommended, and participation initially in a supervised cardiac rehabilitation programme is advised for those recovering from a recent CHD event. 

Food and Nutrition 

The National Cholesterol Education Program recommended the Therapeutic Lifestyle Change (TLC) diet which focuses on fresh vegetables and fruits and wholegrain products and consumption of monounsaturated fatty acids. A goal is to keep total fat intake to 25–35 per cent of total calories, monounsaturated fat intake to up to 20 per cent of total calories, fibre intake at 20–30 g per day, and balancing energy intake and expenditure. Use of stanol ester margarine supplements and fish oil supplementation can provide additional benefits on lipid levels and other cardiovascular risk factors. Most recent ACC/AHA guidelines focus on recommending a dietary pattern that emphasizes intake of vegetables, fruits, and wholegrains; includes low-fat dairy products, poultry, fish, legumes, non-tropical vegetable oils and nuts; and limits intake of sweets, sugar-sweetened beverages, and red meats. Additional recommendations include consumption of no more than 2400 mg of sodium per day, or at least a 1000 mg reduction in daily sodium intake. 

Specific Additional Recommendations for Secondary Prevention of CVD 

Besides lipid control, blood pressure, antiplatelet, diabetes control, and lifestyle recommendations discussed in previous subsections, guidelines for secondary prevention also include therapy with a beta blocker, renin angiotensin and aldosterone system blockers, as well as annual influenza vaccination. Specific systems implemented in the hospital setting, such as pre-printed discharge instructions, reminders on charts (which can be automated in the case of electronic medical records systems) are key to ensure maximal adherence to recommended therapies for secondary prevention of CHD.

1. Smith, S.C. et al. “AHA/ACCF Secondary Prevention and Risk Reduction Therapy for Patients with Coronary and Other Atherosclerotic Vascular Disease: 2011 Update.” Journal of the American College of Cardiology, vol. 58, no. 23, November 2011, pp. 2432–2446.

2. Expert Panel on Detection, Evaluation, and Treatment. et al. “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.” JAMA, vol. 285, no. 19, May 2001, pp. 2486–2497.

3. Chobanian, A.V. et al. “The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: The JNC 7 Report.” JAMA, vol. 289, no. 19, May 2003, pp. 2560–2571.

4. James, P.A. et al. “2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults: Report from the Panel Members Appointed to the Eighth Joint National Committee (JNC 8).” JAMA, vol. 311, no. 5, February 2014, pp. 507–520.

5. Stone, N.J. et al. “2013 ACC/AHA Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults.” Journal of the American College of Cardiology, vol. 63, no. 25, Part B, 2014, pp. 2889–2934.

6. Luepker, R.V. et al. “Tobacco Use, Passive Smoking, and Smoking Cessation Interventions.” Preventive Cardiology: A Practical Approach, 2nd ed., McGraw Hill, 2005, pp. 217–250.

7. Gæde, P. et al. “Effect of a Multifactorial Intervention on Mortality in Type 2 Diabetes.” New England Journal of Medicine, vol. 358, no. 6, February 2008, pp. 580–591.

8. Wong, K. et al. “Comparison of Demographic Factors and Cardiovascular Risk Factor Control among U.S. Adults with Type 2 Diabetes by Insulin Treatment Classification.” Journal of Diabetes and Its Complications, vol. 26, no. 3, May 2012, pp. 169–174.

9. American Diabetes Association. “Executive Summary: Standards of Medical Care in Diabetes 2013.” Diabetes Care, vol. 36, suppl. 1, 2013, pp. S4–S10.

10. James, P.A. et al. “2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults: Report from the Panel Members Appointed to the Eighth Joint National Committee (JNC 8).” JAMA, vol. 311, no. 5, February 2014, pp. 507–520.

11. Eckel, R.H. et al. “2013 AHA/ACC Guideline on Lifestyle Management to Reduce Cardiovascular Risk.” Journal of the American College of Cardiology, vol. 63, no. 25, Part B, July 2014, pp. 2960–2984.