Dr Alan Begg explains how cardiac rehabilitation programmes have an important role in the secondary prevention of CVD


The traditional model of secondary prevention of cardiovascular disease (CVD) consists of identifying individuals with established disease and ensuring lifestyle changes and providing appropriate drug therapy to prevent a future event. Separating individuals into primary or secondary prevention categories does however fail to recognise the continuous nature of CVD risk from low to high risk of a future event (i.e. although prevention may be labelled primary or secondary, there is a continuum of risk).

 

Secondary prevention programmes for CVD have been shown to have positive effects on the processes of care (particularly the use of proven therapies), risk factor profiles, and quality of life.1 Such programmes have resulted in a 17% reduction in subsequent myocardial infarctions over a median follow up of 12 months and the benefit to mortality is more apparent with longer follow up.1

One study has indicated that attendance by patients with coronary heart disease (CHD) at UK nurse-led secondary prevention clinics at general practices leads to fewer deaths and coronary events.2 After adjusting for age, sex, and baseline secondary prevention the proportional hazard ratios were 0.75 for all deaths (95% confidence interval [CI] 0.58–0.98, p=0.036) and 0.76 for coronary events (95% CI 0.58–1.00, p=0.049).2

 

Cardiac rehabilitation (CR) has an important role in supporting and encouraging patients with cardiac disease to maintain optimal physical and psychological health. There are four traditional phases of CR:3

  1. The immediate inpatient care after the event
  2. The early post-discharge period
  3. A structured exercise-based programme in a hospital setting
  4. Long-term maintenance of physical activity and lifestyle changes.

The fourth phase coincides with the long-term follow up and care provided by primary care. The boundaries between secondary prevention of CVD and cardiac rehabilitation are blurred, which can often result in duplication of individual roles and a general feeling of reduced clinical and cost effectiveness. Primary care healthcare teams will be aware of the similarities between the core components of CR (see Box 1) and their own role in the secondary prevention and monitoring of CVD.4

Box 1: Core components of cardiac rehabilitation4
  • Patient assessment
  • Physical activity counselling
  • Exercise training
  • Diet and nutritional counselling
  • Weight control management
  • Lipid management
  • Blood pressure monitoring
  • Smoking cessation
  • Psychological management

 

Is there an optimum way of providing effective CR and secondary prevention as demands on health service budgets increase? Hasnain Dalal, a GP in Truro, Cornwall, and his colleagues, have recently published a Cochrane systematic review and meta-analysis comparing home-based CR with centre-based CR.5 This analysis included 12 trials, three of which were based in the UK. The review showed that there was:5

  • evidence of superior adherence to the programme regimens in home-based participants
  • no difference in terms of:
    • mortality (relative risk 1.31; 95% CI 0.65–2.66)
    • cardiac events for the two trials in which they were reported
    • exercise capacity
    • systolic blood pressure
    • cholesterol
    • smoking
    • health-related quality of life
  • no cost difference for home-based programmes when compared with those that were centre based.

An accompanying editorial to the Dalal article highlights that home-based CR programmes can provide support for a longer period than centre-based ones and in more familiar surroundings, but that centre-based programmes offer the reassurance and increased safety of a clinical setting.6 The latter also permits easier and greater access to a full range of healthcare professionals, although centralisation can reduce service access and weakens links with general practice. It may be that home-based CR is one of several effective models for providing secondary prevention of CVD in the community although good local coordination with primary care is essential. As the exercise component of CR may be difficult for general practice to organise, there is a clear opportunity to draw on established models and adapt them to local situations and needs with benefits for all.

 

The quality and outcomes framework (QOF) has been the stimulus to provide structured secondary prevention of CVD within primary care, but there is scope for it to be more effective in the implementation of the evidence and in determining the process of care.

The reduction in cholesterol achieved by statin treatment regimens results in major health benefits for patients at high risk. A meta-analysis of 90,056 individuals demonstrated a 12% proportional reduction in all-cause mortality per mmol/l reduction in low density lipoprotein cholesterol (rate ratio 0·88; 95% CI 0·84–0·91, p=0·0001). This re?ected a 19% reduction in coronary mortality (0·81; 0·76–0·85, p=0·0001).7

However, the points for the QOF indicator CHD 8 (i.e. the percentage of patients with CHD whose last measured total cholesterol [measured in the previous 15 months] is ?5 mmol/l) can be achieved without the use of a statin, or by using an alternative lipid lowering agent, or indeed without any lipid-lowering medication in some cases.8 In indicators CHD 10, CHD 11, HF 3, and HF 4, points are currently obtained for ensuring patients are receiving a particular drug class, but there is no requirement to ensure that optimum doses are being used.

There would be merit in the QOF reflecting the standards for heart disease care recently published for the NHS in Scotland.9 One of these standards recommends that patients with established CHD are reviewed within 3 months of diagnosis so that risk factors and drug therapy are optimised.9 Similarly there is provision for annual review of all patients with CHD.

Responsibility for updating the QOF is now the remit of NICE. However with the change of UK Government, the role of NICE may change. There is an opportunity for improving the secondary prevention of CHD through the setting of achievable and realistic clinical standards. This will involve closer coordination of secondary care, CR schemes, and the management of long-term conditions through the QOF. This improved coordination will lead to the realisation of the clinical benefits of secondary prevention, will be cost effective, and may reduce overall costs.

 

The uptake of secondary prevention within the UK has increased dramatically in recent years. The setting of standards of care can aid this process, but there remains scope for improved coordination of that care and better implementation of evidence-based practice.

The various models of CR will continue to be part of secondary prevention as they have an important role in reducing the risk of future cardiovascular events.

 

  1. Clark A, Hartling L, Vandermeer B, McAlister F. Meta-analysis: secondary prevention programs for patients with coronary artery disease. Ann Intern Med. 2005; 143 (9): 659–672.
  2. Murchie P, Campbell N, Ritchie L et al. Secondary prevention clinics for coronary heart disease: four year follow up of a randomised controlled trial in primary care. BMJ 2003; 326 (7380): 84.
  3. Scottish Intercollegiate Guidelines Network. Cardiac rehabilitation. A national clinical guideline. SIGN 57. Edinburgh: SIGN, 2002. Available at: www.sign.ac.uk/guidelines/fulltext/57/index.html
  4. Piepoli M, Corrà U, Benzer W et al; Cardiac Rehabilitation Section of the European Association of Cardiovascular Prevention and Rehabilitation. Secondary prevention through cardiac rehabilitation: from knowledge to implementation. A position paper from the Cardiac Rehabilitation Section of the European Association of Cardiovascular Prevention and Rehabilitation. Eur J Cardiovasc Prev Rehabil 2010; 17 (1): 1–17.
  5. Dalal H, Zawada A, Jolly K et al. Home based versus centre-based cardiac rehabilitation: Cochrane systematic review and meta-analysis. BMJ 2010; 340: b5631.
  6. Clark A. Home based cardiac rehabilitation. BMJ 2010; 340: b5510.
  7. Baigent C, Keech A, Kearney P et al; Cholesterol Treatment Trialists’ (CTT) Collaborators. Efficacy and safety of cholesterol-lowering treatment: prospective meta-analysis of data from 90,056 participants in 14 randomised trials of statins. Lancet 2005; 366 (9493): 1267–1278.
  8. British Medical Association. Quality and outcomes framework guidance for GMS contract, 2009/10. Delivering investment in general practice. London: BMA, 2009. Available at: www.bma.org.uk/employmentandcontracts/independent_contractors/quality_outcomes_framework/
  9. NHS Quality Improvement Scotland. Clinical standards April 2010—Heart disease. Edinburgh: NHS QIS, 2010. Available at: www.nhshealthquality.org/nhsqis/files/HD_STANF_APR10.pdfG