The long awaited second Joint British Societies’ Guidelines on the Prevention of Cardiovascular Disease in Clinical Practice (JBS 2) was published last month.1 The first recommendations published seven years ago were restricted to the prevention of coronary heart disease (CHD) and the original four societies have now been joined by the Stroke Association and the Primary Care Cardiovascular Society.
It is encouraging to see primary care represented as the guidelines recommend that general practice should take the lead in screening all adults aged 40 years and over for cardiovascular disease (CVD) risk.
In order to reflect the stroke risk, CVD risk rather than CHD risk using the Framingham function should be measured. JBS 2 continues the trend to remove the artificial barrier between primary and secondary prevention. Those with established atheosclerotic CVD, diabetes or a 10-year CVD risk ≥20% are regarded as high risk and have equal priority for CVD prevention.
Previously it has been accepted that people with an elevated single risk factor,such as systolic BP ≥160 mmHg, diastolic BP ≥100 mmHg or familial dyslipidaemia, should receive therapeutic intervention, but now people with a total cholesterol: HDL cholesterol ratio ≥6 are also included.
Treatment of a 40-year-old male with this lipid profile and no other risk factors could only be justified on global risk measurement if his age is projected to 59.
The concern regarding this approach is that drug treatment will be commenced on the basis of an isolated cholesterol level without a full risk assessment being carried out. A measured HDL cholesterol >1 as opposed to an assumed level of 1 will, however, give a lower ratio and a lower risk.
Reflecting the evidence for lower cholesterol levels, the target for total cholesterol is <4 mmol>
In practice aiming for a lower cholesterol target ensures that the audit standard is always met despite the assay coefficient of variation. Practice cardiovascular nurses are fully aware of the problem of varying cholesterol levels, having seen patients who have not continued to meet the target this year despite not changing their medication or lifestyle.
JBS 2 will not have a huge immediate impact on general practices as the first stage review of the nGMS contract does not envisage any significant changes to the CHD, stroke, diabetes or hypertension categories. Although indicators for atrial fibrillation are now included, peripheral arterial disease has not been added.2
There is also no provision for the recommendation of practice-based risk assessment of those aged 40 years and over, even on an opportunistic basis.
For those practices in a position to implement this guidance, although no cost effectiveness or cost implication data is included, the Wanless report on the future funding of the NHS did assume that statins would be made available to all those with a 10-year risk of developing CVD ≥20%. 3 The numbers potentially eligible for preventative care are included in the guideline. Although over 20% of adults may have a cholesterol level above 6.5mmol/l, a mean HDL cholesterol level of 1.5mmol/l does result in a lower ratio.4,5 The NICE final appraisal determination on statins for the prevention of cardiovascular disease notes that statin therapy would be cost effective for all age groups with a 10-year CVD risk ≥20%. This would mean that in England and Wales 3.3 million would be eligible for the initiation of statin therapy.6
The need for a more robust approach to the prevention of CVD will be reinforced with the SIGN guideline on the prevention of CHD later this year and in due course the NICE guideline on lipid modification.
- JBS 2: Joint British Societies’ Guidelines on Prevention of Cardiovascular Disease in Clinical Practice. Heart 2005:91 (suppl V); v1-v52.
- Wanless D. Securing Our Future Health: Taking a Long-Term View. London: HM Treasury, 2002. http://www.hm-treasury.gov.uk/
- Health Survey for England 2003. http://www.archive2.official-documents.co.uk
- The 1995 Scottish Health Survey. http://www.archive.official-documents.co.uk