Prevention of cardiovascular disease

See the separate articles Cardiovascular Risk Assessment and Cardiac Rehabilitation.

The revised Joint British Societies' (JBS 3) guidelines on prevention of cardiovascular disease (CVD) in clinical practice recommend that CVD prevention should focus equally on the following three groups of patients who are at high risk of CVD:¹

• Apparently healthy individuals with 10% or greater risk over 10 years of developing symptomatic atherosclerotic disease.

• People with diabetes mellitus (type 1 or 2).

• People with established atherosclerotic CVD.

Cardiovascular risk calculation

Whenever risk factors are identified they should not be considered in isolation, but the 10-year CVD risk should be calculated and used as the basis for recommendations to reduce the risk.

Risk assessment should include ethnicity, smoking habit history, family history of CVD and measurements of weight, waist circumference, blood pressure, lipids (total cholesterol and high-density lipoprotein (HDL) cholesterol) and glucose. In the UK the QRISK score is recommended for estimating 10-year risk in people aged 40-84 who do not have CVD, or are not already at high risk of CVD because of another condition such as hyperlipidaemia or diabetes.²

The American Heart Association (AHA) guidelines also recommend recording the pulse rate and rhythm to screen for atrial fibrillation:³

The European Society of Cardiology (ESC) recommends a total CVD risk assessment using the SCORE (= Systemic Coronary Risk Evaluation) project approach.⁴

This consists of charts which provide a risk assessment over a patient's lifetime, with different charts for high- and low-risk countries. This replaces the notion of primary and secondary CVD prevention. For example, patients with CKD and no other cardiac risk factors should be treated as very high-risk.

For further details see the separate article Cardiovascular Risk Assessment.

The healthy individual

The NHS Live Well page gives advice on the following:⁵

• Stopping use of tobacco.

• Physical activity - at least 30 minutes, five times a week.

• Healthy eating.

• Not being overweight.

• Having a BP <140/90 mm Hg.

• Having a total cholesterol <5 mmol/L.

• Normal glucose metabolism.

• Avoidance of stress.

• Sleeping well and avoiding tiredness.

• Maintaining sexual health.

Interventions

Reduction of risk of developing CVD involves lifestyle modifications, drug treatment and effective management of any overt underlying medical condition - eg, diabetes, hypertension, hyperlipidaemia.^{2 3 4} Sex disparities exist in achieving risk factor lowering modifications; after adjusting for several factors that could have influenced the results, researchers found that, (compared with men), women were less likely to achieve targets for total cholesterol, LDL cholesterol and blood glucose, or to be physically active or non-obese, but they were more likely to control blood pressure and be non-smokers.⁶

Lifestyle modifications

Programmes for cardiac rehabilitation are active in the UK and consist of patient education, exercise training and mental support;⁷ much of this work occurs within the community.

• QOF for UK surgeries requires maintaining a disease register and systematic recall with a nurse-led clinics. Evidence supports their efficacyfor use in CVD and diabetes when the nurses have undergone appropriate training.⁸ Invite people aged 40-74 to attend for an NHS health check.

• Smoking cessation: all patients should be actively discouraged from smoking - repeated brief supportive advice, combined with nicotine replacement therapy when needed.²

• Keep total dietary intake of fat to a maximum of 30% of total energy intake, with intake of saturated fats 10% or less of total fat intake and the intake of dietary cholesterol to less than 300 mg/day. Trans fats intake should be kept to a minimum .

• Consumption of fresh fruit and vegetables should be increased to at least five portions per day. Unsalted nuts, seeds and legumes at least five 30 g portions per week. Wholegrain fibre 30-45 g per day. Evidence for the Mediterranean diet is of low-moderate quality but may be beneficial for primary prevention.⁹ Two portions per week of fish and at least one of those to be oily fish.²

• Limit the intake of salt to less than 100 mmol/L per day (less than 5 g of salt per day). ¹⁰

• Alcohol consumption should be limited to three units per day and no more than 14 units per week for men and women, ideally with two alcohol-free days.¹¹

• Patients should be encouraged to exercise regularly:²
  

  • Exercise training has been shown to slow the progression or partially reverse the severity of coronary atherosclerosis.

  • Aerobic exercise can modify all the components of the metabolic syndrome with a decrease in blood pressure and triglycerides, increase in HDL, and an improvement of insulin sensitivity.

• Weight control:²
  

  • Overweight patients should be encouraged to lose weight through a combination of diet and exercise.

  • Maintain an ideal body weight for adults (body mass index 20-25 kg/m²) and avoid central obesity (waist circumference in white people less than 102 cm (40 inches) in men and less than 88 cm (circa 34½ inches) in women); in Asians, the recommended targets are less than 90 cm (35 inches) in men and less than 80 cm (circa 31½ inches) in women.

Blood pressure management

See also the separate article Hypertension Treatment:

• The optimal blood pressure target is less than 140 mm Hg systolic and less than 90 mm Hg diastolic.

• In selected higher-risk people (eg, established atherosclerotic disease, diabetes, and chronic kidney disease) a lower blood pressure target of less than 130 mm Hg and less than 80 mm Hg may be more appropriate. ¹²

Lipid management¹³

See also separate article Hyperlipidaemia:

• The optimal total cholesterol target is less than 4.0 mmol/L and low-density lipoprotein (LDL) cholesterol less than 2.0 mmol/L. The aim is to achieve a greater than 40% reduction in non-HDL cholesterol levels.¹⁴

• Fasting lipids should be estimated at least eight weeks after an acute cardiovascular event and, if necessary, the dose of statin up-titrated to achieve the target.

• Atorvastatin 20 mg is recommended for primary prevention of CVD.

• Primary prevention is for those who are at >10% risk of developing CVD.^{13 15}

• There is good evidence that statins rarely cause adverse reactions or muscle pains.¹⁶

• Other classes of lipid-lowering drugs (particularly fibrates, bile acid sequestrants, cholesterol absorption inhibitors, nicotinic acid, omega-3 (n-3) fatty acids) should be considered in addition to a statin if the required targets have not been achieved, or if there are other lipid abnormalities.

Blood glucose and diabetes²

• In all high-risk people the optimal fasting glucose is less than 6.0 mmol/L.

• People with impaired fasting glycaemia or impaired glucose tolerance should be reviewed annually to reassess glucose regulation and all other cardiovascular risk factors.

• People with types 1 and 2 diabetes mellitus require rigorous control of glycaemia. The optimal target for glycaemic control in diabetes is a fasting or preprandial glucose value of 4.0-6.0 mmol/L and an HbA1c less than 6.5%, but individual circumstances may dictate more lenient goals.

Antithrombotic therapy

• Coronary or peripheral atherosclerosis:
  

  • Aspirin 75 mg daily should be considered for all people with established coronary or peripheral atherosclerotic disease. If aspirin is contra-indicated, or there are side-effects, then clopidogrel is appropriate.

  • There is evidence that aspirin doubles the risk of gastrointestinal bleeding and current opinion is that this outweighs any benefits which might be conferred in reducing the onset of CVD.¹⁷ Therefore aspirin is NOT currently recommended of primary prevention.

  • Anticoagulation should be considered for selected people at risk of systemic embolisation from large myocardial infarctions, heart failure, left ventricular aneurysm, or paroxysmal tachyarrhythmias.

• Cerebral atherosclerotic disease (non-haemorrhagic):

  • All people with a history of cerebral infarction, or transient ischaemic attack, and who are in sinus rhythm, should take low-dose aspirin plus modified-release (MR) dipyridamole for two years following the initial event to prevent stroke recurrence as well as other vascular events.

  • For those who have a further ischaemic cerebrovascular event while taking aspirin and MR dipyridamole, then changing aspirin for clopidogrel should be considered.

  • Anticoagulation with warfarin or direct oral anticoagulant should be considered for all people with atrial fibrillation who are at moderate (aged 60-75 years without additional risk factors) to high risk (over 75 years, or over 60 years with other risk factors such as hypertension, diabetes, or left ventricular dysfunction) to reduce the risk of a further stroke, according to CHA2Ds2-VASc score.¹⁸

    • If oral anticoagulation is contra-indicated, or cannot be tolerated, antiplatelet therapy should be considered instead.

    • There is no evidence of benefit for anticoagulation in people with ischaemic stroke who are in sinus rhythm.

Anti-arrhythmic agents

These medications are not used in primary prevention. They have specific indications such as beta-blockers for atrial fibrillation and post cardiac events.

Surgery

After assessment with an exercise tolerance test, echocardiography, angiography, and scanning, the following may be beneficial where appropriate:

• Coronary artery bypass grafting: reduces mortality compared with medical treatment alone, particularly in those with poor left ventricular function.

• Percutaneous transluminal coronary angioplasty (PTCA).

• Intracoronary stent: particularly useful for restenosis after PTCA.

• Atherectomy by various methods, and transmyocardial laser revascularisation are less common procedures used.

Psychosocial risk factors

Increased CVD death and disability have been associated with:²

• Low socio-economic status

• Social isolation

• Work-related stress

• Depression

• Panic attacks

Some of these risk factors can be difficult to control for and require intervention at a government level.

Future aspects of CVD prevention

Effective CVD prevention depends in part on accurate determination of risk. Risk determination is more difficult in those who are asymptomatic. Newer aspects of risk determination include novel biomarkers and imaging modalities. Additionally, considerable energies are advancing the growth of digital technologies and Big Data for the future of population-level CVD prevention.^{19 20}