Main In the UK, cardiovascular disease (CVD) remains the most common cause of death, including premature death (under the age of 65 years).1 The causes of CVD are multifactorial and the presence of several risk factors has an increasing effect on the likelihood of developing the disease. The rationale for the primary prevention of CVD is that through addressing individual risk factors for the disease, either by lifestyle or therapeutic intervention, the risk of the individual suffering a cardiovascular (CV) event can be reduced. A population approach to CVD primary prevention focuses mainly on lifestyle and behavioural habits whereas the alternative is a targeted approach to identify and manage those individuals at higher risk who have potentially more to gain from a change in lifestyle or therapeutic intervention.
Primary prevention of CVD in the QOF
For the first time, two indicators relating to the primary prevention of CVD were added in the 2009 update of the quality and outcomes framework (QOF)—PP 1 and PP 2 (see Table 1).1 A total of 13 points are available for carrying out a face-to-face risk assessment and providing lifestyle advice for patients with new diagnoses of hypertension.
For indicator PP 1, the actual risk assessment needs to be carried out within 3 months of the new diagnosis being made (i.e. 3 months before or 3 months after) and the values used in this assessment should have been recorded no longer than 6 months before the date of the risk assessment and prior to any treatment for hypertension.1 The QRISK 2 risk calculator does however include ‘on blood pressure treatment’ as part of the clinical information considered.2 Certain patient groups can be excluded from undergoing the risk assessment on the basis that they are already deemed to be at high risk (see Box 1). Indicator PP 2 specifies that the lifestyle advice should be provided in the past 15 months to those patients diagnosed with hypertension after 1 April 2009.
|Table 1: Quality and outcomes framework clinical indicators 2009/10 for cardiovascular disease—primary prevention1|
|In those patients with a new diagnosis of hypertension (excluding those with pre?existing CHD, diabetes, stroke and/or TIA) recorded between the preceding 1 April to 31 March: the percentage of patients who have had a face-to-face cardiovascular risk assessment at the outset of diagnosis (within 3 months of the initial diagnosis) using an agreed risk assessment tool||8||40–70%|
|PP 2||The percentage of people with hypertension diagnosed after 1 April 2009 who are given lifestyle advice in the last 15 months for: increasing physical activity, smoking cessation, safe alcohol consumption, and healthy diet||5||40–70%|
|CHD=coronary heart disease; TIA=transient ischaemic attack|
|Box 1: Risk assessment exclusion|
|Risk equations should not be used for patients:
Assessment of CVD risk
It is generally accepted that the CVD risk should be assessed in order to reflect the stroke risk rather than only the coronary heart disease (CHD) risk.3,4 Although it is absolute risk that is measured, there are situations in younger individuals where a high relative risk over the lifetime of the individual may be important and should be addressed. This would include individuals with a positive family history of premature CVD or a high total cholesterol:high-density lipoprotein cholesterol ratio.
The QOF states that the risk assessment for indicator PP 1 should be carried out using an agreed tool.1 The main risk assessment score in use is the Framingham 1991 10-year risk equation, although practices in Scotland are given the option of using the ASSIGN risk score (see Table 2).3,4
The Framingham equation is based on a predominantly white US population from the 1970s and is the most widely accepted method for estimating CVD risk. However, it results in underestimation of risk in socially deprived groups as well as in British Asians,3 and appears to overestimate the risk in other groups. The NICE guideline on lipid modification recommends that the Framingham equation is used as part of a systematic strategy to identify people aged 40–74 years who are likely to be at high risk.5 Furthermore, patients with a 10-year CVD risk of ?20% should be prioritised for a full formal risk assessment and modification of that risk.5
The ASSIGN score was derived from the Scottish Heart Health Extended Cohort and was developed to include social deprivation and family history (providing an indirect approach to ethnic susceptibility) as risk factors for CVD (see Table 2). Comparison of ASSIGN with Framingham reflects the overestimation seen with the latter. Moreover, ASSIGN will identify more people with a positive family history and more people who are socially deprived as being at high risk.3
It was recently suggested that a QRISK-based algorithm should replace the current recommended Framingham-based algorithm for estimating CV risk in the UK.6 Although nearly 80% of participants in the original database from which QRISK 1 was developed had some missing risk prediction variables, a recent validation has concluded that the magnitude of 10-year CVD risk under prediction using QRISK is smaller than the over prediction resulting from using Framingham.6–8
A revised algorithm, QRISK 2, incorporates self-assigned ethnicity and measures of social deprivation as well as other relevant conditions associated with CV risk, including type 2 diabetes, treated hypertension, rheumatoid arthritis, renal disease, and atrial fibrillation.9 The developers of QRISK 2 state that at the 20% threshold, it is likely to be a more efficient and equitable tool than Framingham for treatment decisions in the primary prevention of CVD although they do indicate that further validation is advised.9
|Table 2: Comparison of the variables required for Framingham, ASSIGN, and QRISK|
|Age and sex
||Age and sex||Age and sex|
|Systolic and diastolic BP||Systolic BP||Systolic BP|
|Diabetes||Diabetes||Body mass index|
|Smoking status||Smoking status||Smoking status|
|Left ventricular hypertrophy||Family history of CHD/stroke <60 years||Family history of CHD/stroke <60 years|
|–||Deprivation index-linked to six-digit postcode||Area measure of deprivation|
|aAnderson K, Odell P, Wilson P. Cardiovascular disease risk profiles. Am Heart J 1991; 121 (1 Pt 2): 293–298.
bTunstall-Pedoe H, Woodward M; SIGN group on risk estimation. By neglecting deprivation, cardiovascular risk scoring will exacerbate social gradients in disease. Heart 2006; 92 (3): 307–310.
cHippisley-Cox J, Coupland C, Vinogradova Y et al. Derivation and validation of QRISK, a new cardiovascular disease risk score for the United Kingdom: prospective open cohort study. BMJ 2007; 335 (7611): 136.
*QRISK 2, a revised algorithm, incorporates self-assigned ethnicity and a range of potentially relevant conditions, such as type 2 diabetes, treated hypertension, rheumatoid arthritis, renal disease, and atrial fibrillation.
BP=blood pressure; TC=total cholesterol; HDL=high-density lipoprotein; CHD=coronary heart disease
Management of CVD risk
The assessment of CVD risk is used to identify individuals at high risk in order to provide them with advice on intensive lifestyle management. It is also used to inform the clinician on the possible use of blood-pressure lowering, lipid-lowering, and possible aspirin therapy. The criteria for this high-risk threshold remains a 10-year CVD risk of ?20%.3–5
The assessment of risk under the QOF (PP 1) relates to patients newly diagnosed with hypertension. In terms of managing patients after diagnosis, the hypertension indicators in the QOF remain unchanged apart from a 2-point reduction to 18 points for BP 4 (percentage of patients with hypertension in whom there is a record of blood pressure in the previous 9 months).1 The NICE guideline on hypertension recommends drug therapy to reduce the risk of CVD and death in those patients with:10
- persistent high blood pressure of ?160/100 mmHg
- a 10-year CVD risk ?20% or existing CVD or target organ damage with a persistent blood pressure >140/90 mmHg.
A recent meta-analysis involving 70,388 patients without established CVD but with CV risk factors showed that statin therapy was associated with significant risk reductions of:11
- 12% in all-cause mortality
- 30% in major coronary events
- 19% in cerebrovascular events.
The implications from the study are that patients who are estimated to be at higher risk in a primary prevention situation will benefit from the use of statin therapy. The authors conclude that the correct identification of individuals who will benefit the most from statin therapy remains a challenge.11 It would be logical to consider statin treatment for patients with hypertension as identified through the QOF process (PP 1).
At a CVD risk level of 20%, it is accepted that once the blood pressure is controlled to <150/90 mmHg, the benefit of low-dose aspirin (75 mg) outweighs the harm.12 It has recently been shown that in the primary prevention trials of aspirin there was a proportional reduction in serious vascular events (0.51% aspirin vs 0.57% control per year, p=0.0001) mainly because of a reduction in non-fatal myocardial infarction (0.18% vs 0.23% per year, p<0.0001).13 However, many of the patients in these trials were not taking statins, and on balance, statins may be preferable to aspirin until it is certain that there is additional benefit from aspirin in this clinical situation, with little or no risk. Recent doubts on the benefits of aspirin in the primary prevention of CVD have again been raised with the presentation of the Aspirin for Asymptomatic Atherosclerosis (AAA) trial.14 This study involved the use of 100 mg enteric-coated aspirin in a group of patients without CVD but at a higher risk on the basis of a low ankle brachial index (<0.95). There was no statistical difference between the aspirin or placebo group in the primary endpoint composite of initial fatal or non-fatal coronary event or stroke or revascularisation. This was also the case for the two secondary endpoints of initial vascular events and all-cause mortality.14
Coding CV risk
Codes are available for practices to record which risk score has been used (see Box 2).15 Current Framingham codes, which refer to CHD risk rather than CVD risk, are being revised and should be published in October 2009, with the Joint British Societies’ codes removed in due course. There is a single code covering advice on increasing physical activity, smoking cessation, safe alcohol consumption, and a healthy diet to meet the requirement of PP 2.
It is unfair to expect practices to enter clinical data twice (once for risk scoring and once for practice records) when embedded systems are available that are crucial to the success of risk assessment.6,16 A validation of QRISK 2 using the QRESEARCH database, which is a primary care electronic database developed from practices using the Egton Medical Information System (EMIS) practice system, has been published by the developers.9 However, there are financial implications for other primary care computer systems incorporating the QRISK algorithm and there is concern over these commercial restrictions.6
|Box 2: Cardiovascular risk codes15|
The lifestyle advice in indicator PP 2 for patients with newly diagnosed hypertension is broadly in line with that of the NICE guideline on managing hypertension, which states that:10
- education about lifestyle on its own is unlikely to be effective
- healthy low-calorie diets in overweight individuals will reduce raised blood pressure
- aerobic exercise for 30–60 minutes, three to five times each week can have a small effect on blood pressure
- a combination of exercise and diet will reduce systolic and diastolic blood pressure by 4–5 mmHg
- alcoholic consumption (>21 units/week in men, >14 units in women) is associated with raised blood pressure
- smoking should be discouraged to improve CVD risk, but there is no strong direct link between smoking and blood pressure
- excessive consumption of dietary salt and caffeine-rich products should be discouraged
- relaxation therapies may be useful in lowering blood pressure (routine provision of this treatment by primary care is not currently recommended).
NHS Health Check
The NHS Health Check: vascular risk assessment and management is a national initiative in England to identify patients at risk of CVD, and in particular those at high risk.17 However, there is no equivalent programme in Scotland or Wales. The NHS Health Check will identify patients with hypertension, chronic kidney disease, and diabetes, but ongoing recall and management will be the responsibility of GP practices and covered by the QOF indicators. Ideally practices need to be informed of all of the results from this national programme, and in particular those relating to newly diagnosed patients with hypertension, thereby assisting practices in complying with PP 1.
The limited introduction of the primary prevention of CVD into the QOF is a welcome first step. Incorporating the vascular risk programme in its entirety across the UK into the QOF process would be the logical next step to provide universal coverage. Limited practice capacity without appropriate resources might be a barrier but it would provide a unique opportunity for primary care and independent providers to work together. Once identified, high-risk patients become the responsibility of general practice, which must remain pivotal in the whole process. An integrated approach through QOF would be a cost-effective way in making a significant difference in the primary prevention of CVD.
- General Practitioners Committee, NHS Employers. Quality and outcomes framework guidance for GMS contract 2009/10. Delivering investment in general practice. London: BMA, NHS Employers, 2009.
- QRISK®2 cardiovascular disease risk calculator. www.qrisk.org/index.php (accessed 23 September 2009).
- Scottish Intercollegiate Guidelines Network. Risk estimation and the prevention of cardiovascular disease. SIGN 97. Edinburgh: SIGN, 2007. Available at: www.sign.ac.uk/guidelines/fulltext/93-97/index.html
- British Cardiac Society, British Hypertension Society, Diabetes UK et al. JBS 2: Joint British Societies’ guidelines on prevention of cardiovascular disease in clinical practice. Heart 2005; 91 (Suppl 5): 1–52.
- National Institute for Health and Care Excellence. Cardiovascular risk assessment and the modification of blood lipids for the primary and secondary prevention of cardiovascular disease. Clinical Guideline 67. London: NICE, 2008. Available at: www.nice.org.uk/guidance/CG67
- Jackson R, Marshall R, Kerr A et al. QRISK or Framingham for predicting cardiovascular risk? BMJ 2009; 339: b2673. doi: 10.1136/bmj.b2673
- Collins G, Altman D. An independent external validation and evaluation of QRISK cardiovascular risk prediction: a prospective open cohort study. BMJ 2009; 339: b2584. doi: 10.1136/bmj.b2584.
- Collins G, Altman D. An independent validation of QRISK on the thin database. Oxford: Centre for Statistics in Medicine, 2009. Available at: www.dh.gov.uk/en/Publicationsandstatistics/Publications/PublicationsPolicyAndGuidance/DH_103341
- Hippisley-Cox J, Coupland C, Vinogradova Y et al. Predicting cardiovascular risk in England and Wales: prospective derivation and validation of QRISK2. BMJ 2008; 336 (7659): 1475–1482.
- National Institute for Health and Care Excellence. Hypertension: management of hypertension in adults in primary care. Clinical Guideline 34. London: NICE, 2006. Available at: www.nice.org.uk/guidance/CG34
- Brugts J, Yetgin T, Hoeks S et al. The benefits of statins in people without established cardiovascular disease but with cardiovascular risk factors: meta-analysis of randomised controlled trials. BMJ 2009; 338: b2376.
- Williams B, Poulter N, Brown M et al. Guidelines for management of hypertension: report of the fourth working party of the British Hypertension Society, 2004-BHS IV. J Hum Hypertens 2004; 18 (3): 139–185.
- Antithrombotic Trialists’ (ATT) Collaboration. Aspirin in the primary and secondary prevention of vascular disease: collaborative meta-analysis of individual participant data from randomised trials. Lancet 2009; 373 (9678): 1849–1860.
- Fowkes F, Price J, Stewart M et al. Aspirin for Asymptomatic Atherosclerosis trialists: Randomised controlled trial of low dose aspirin in the prevention of cardiovascular events and death in subjects with asymptomatic atherosclerosis. Available at: www.escardio.org/congresses/esc-2009/congress-reports/Pages/706001-706002-fowkes-patrono.aspx
- Department of Health. New GMS contract QOF implementation: dataset and business rules—established cardiovascular disease primary prevention indicator set. DH, 2009.
- Begg A, Griffith J. The electronic health record and the management of cardiovascular disease. Br J Cardiol 2002; 9: 630–633.
- NHS Health Check Programme. Putting Prevention First—NHS Health Check: Vascular risk assessment and management. Best practice guidance. London: DH, 2009. Available at: www.dh.gov.uk/prod_consum_dh/groups/dh_digitalassets/documents/digitalasset/dh_098410.pdf G
- The QOF indicator PP 1 requires a CVD risk assessment within 3 months of diagnosis of new cases of hypertension
- Framingham is not valid for those patients aged under 40 years or over 75 years and these patients will have to be excluded from this indicator set unless the QOF ruleset is changed
- PBC consortia should consider how best to commission the NHS Health Check to ensure close liaison with GPs who will have to conduct further assessments (around 60% of those screened)
- Primary prevention of CVD in high-risk groups is exceedingly cost effective as long as drugs with low-acquisition costs are used
- PBC consortia should agree local formularies for antihypertensive drugs and statins to ensure cost-effective prescribing and consider incentive schemes to support these choices