Raising the profile of
Disappointed by the non-inclusion of PAD in the new QOF, Professor Cliff Shearman stresses PAD should be considered as much a priority in the fight against CVD as diabetes or hypertension
There are clear indications that peripheral arterial disease (PAD) is low in the public consciousness and underestimated by many health care professionals.
The omission of PAD from the new contract is indicative of this and may have given some health care professionals the impression that the evidence for treating PAD was weak. This could not be further from the truth and it is essential that management of PAD becomes an immediate priority.
Why the low profile?
The low profile of PAD is hard to understand. It may be related to the generally older population affected, and/or its perception as a
relatively mild condition because the most common symptom, intermittent claudication, is considered by some patients to be nothing more than one of the 'normal aches and pains' associated with ageing.
However, this interpretation of the disease is wrong on a number of levels, because:
· About 25 per cent of patients over 55 are likely to have PAD
· PAD is a major cause of amputation in
· People with PAD are six times more likely to die from CVD within 10 years than those with no PAD, and the accrued mortality risk of patients with PAD is 30 per cent within five years rising to 78 per cent within 15 years (compared with 22 per cent in patients with no PAD)
· PAD is a very strong marker of
cardiovascular risk (equivalent to MI or stroke)
The asymptomatic iceberg
More than 60 per cent of patients with PAD are asymptomatic, so in an average practice in the UK there will be six-eight patients with symptomatic PAD and more than 10 asymptomatic PAD patients. And with the continued increase of obesity and diabetes and an ageing population, the incidence of PAD will only increase in the coming decades.
Although symptomatic patients fare worse than asymptomatic PAD patients, even asymptomatic patients have much
lower survival rates than healthy
To put this into context, the death rate five years after the time of diagnosis for a
patient with PAD is twice that of a patient with breast cancer.
In fact, PAD ranks alongside angina, diabetes and even previous myocardial infarction or stroke in importance as a risk factor for CVD.
Identification of PAD can be relatively simple. A history of claudication or a non-healing wound on the foot and absent pulses on clinical examination may alert the doctor to its presence. But the measurement of ankle blood pressure is easy and has become the mainstay of the diagnosis of both symptomatic and non-symptomatic PAD.
A standard 15cm blood pressure cuff is wrapped around the ankle just above
the malleoli. The ankle arteries are assessed in turn with a simple 8mgH Doppler
ultrasound probe. The cuff is inflated until the Doppler signal disappears and is then deflated.
The pressure at which the signal reappears is taken as the perfusion pressure of the foot. It is compared with the arm systolic pressure to calculate a ratio the ankle brachial pressure index (ABPI) which in normal individuals is 1.0.
The ABPI is a major progressive marker of PAD. An ABPI of Ã0.9mmHg is 95 per cent sensitive in detecting angiographically-
defined disease, and importantly can predict an increased risk of mortality or major cardiovascular morbidity.
ABPI is no more difficult to measure than conventional blood pressure and is regularly measured by GPs and practice nurses. For
example, nurses treating patients with leg ulcers will always check the ABPI before
embarking on compression bandaging.
Any patient with exercise-induced leg pain or an ulcer should have their ABPI measured. The benefits of risk factor management are so great that any patient at high risk of PAD should also have their ABPI measured, including those with:
· cerebro-vascular disease
· coronary artery disease
· strong family history of PAD
What GPs can do
Advise on lifestyle management
The single most important intervention a GP can make for a patient with PAD is to get them to stop smoking. Simple advice alone will have little effect but regular encouragement, the use of smoking cessation clinics and substitution therapy can achieve cessation rates of 30 per cent at one year.
Many patients are unaware of the seriousness of PAD and careful counselling is needed to help motivate them to address their lifestyle. Simple walking exercise will reduce cardiovascular risk as well as improving walking distance. The benefits take time to become apparent and patients often need encouragement to continue the programme.
This reduces serious vascular events by 23 per cent in patients with PAD and a large number of trials provide evidence for this: 75mg of soluble aspirin is as effective as
larger doses and has fewer side-effects such as gastrointestinal bleeding; around 15 per cent of patients are unable to tolerate aspirin and in these patients clopidogrel, 75mg once daily, should be used.
Reduction in LDL cholesterol will also result in cardiovascular benefit. The Heart Protection Study showed simvastatin reduced the risk of major vascular events by 19 per cent in PAD patients with cholesterol levels over 3.5 mmol/l.
Other statins are likely to have the same effect, but the most important aspect of treatment is to ensure the patient responds by monitoring their lipids and correcting the dose accordingly. There has been recent interest in the potential role of statins in plaque reduction
The attitude and approach of the health care providers is an essential part of risk factor modification for the patient with PAD. Careful patient education can play a huge role in motivating patients to change their behaviour, and the more enthusiastic and supportive environment, the more successful this is likely to be. Unless the medical profession take PAD seriously it is unlikely the patient will.
Raising awareness with REACH
REACH is a multinational registry of patients with CAD, cerebrovascular disease or PAD (or patients with at least three risk factors for atherothrombosis), which will last for at least 24 months.
Some 63,000 patients from 43 countries have been recruited and the 24-month data was presented at the recent American College of Cardiology meeting in March (see box). REACH has many advantages over previous studies and should make a good case for PAD to be included in the next quality framework.
Barely half of the REACH patients were achieving the treatment targets for hyper-cholesterolaemia and dyslipidaemia, and fewer still achieved the targets for blood glucose levels and blood pressure. Again, REACH showed that patients with PAD alone were particularly badly controlled in this respect.
With the REACH registry confirming the high frequency of multiple cardiovascular risk factors in patients with PAD, it is clear that PAD should be considered as much a priority in the fight against CVD as diabetes or hypertension.
REACH results so far
· Of the 7,663 REACH patients with symptomatic PAD most also had CAD or cerebrovascular disease 37.1 per cent had PAD alone, 39.6 per cent also had CAD, 9.3 per cent had cerebrovascular disease, and 14.1 per cent had all three manifestations of atherothrombosis.
· Among the 2,843 patients in REACH who had PAD but no other manifestation of atherothrombosis, the prevalence of other risk factors for CVD was high: 38.7 per cent had diabetes, 73.3 per cent were hypertensive, 58.7 per cent had hypercholesterolaemia, 46 per cent were former smokers, and 31 per cent were current smokers.
· This high prevalence of multiple risk factors meant that a large proportion of these patients were receiving relevant medication at baseline. However, two significant observations regarding PAD patients were made: 1. only 31.8 per cent of patients with PAD were receiving adequate treatment; 2. the use of medications to treat cardiovascular risk (antihypertensives, antiplatelets, lipid-lowering therapies and nitrates) were used less in the patients with PAD only, compared with use in patients with either CAD only or cerebrovascular disease only. This inevitably results in a large proportion of patients remaining hyperglycaemic,
Cliff Shearman is professor of vascular surgery at the University of Southampton and consultant vascular surgeon at Southampton University Hospitals Trust he is a council member of the Vascular Society of Great Britain
Professor Shearman has received honoraria from Sanofi-Aventis to chair PAD management meetings at the Vascular Society and has received honorarium from Astra Zeneca for speaking on statin therapy and management of PAD to a GP audience. He is a member of the lobbying group (Target PAD) whose aim is to raise the profile of PAD and its meetings are supported by an educational grant from Sanofi Aventis and BSM.