Prompt diagnosis of peripheral arterial disease can optimisepain-free mobility and avoid future amputations, says Dr Alan Begg

Read this article to find out more about:
  • the NICE quality standards and QOF clinical indicators related to PAD
  • how primary care can support management of this condition
  • the importance of carrying out a cardiovascular comorbidities assessment

NICE has now issued 57 quality standards on specific topics.1 Derived from NICE and other accredited guidance, these standards are intended to drive and measure quality improvements within particular areas and are a key component of the Government’s approach to the NHS, as detailed in the Health and Social Care Act 2012.2 As the focus in the NHS shifts from delivering evidence-based care to the measurement of outcomes, standards need to be clear and measurable and audit figures should be published. Quality standards should be based on the appropriate evidence but with the cost impact taken into account.

NICE quality standard on peripheral arterial disease

NICE quality standard (QS) 52 on Peripheral arterial disease (PAD) was published in January 2014 and covers the diagnosis and management of lower limb PAD in adults aged over 18 years (see Table 1, and www.nice.org.uk/guidance/QS52).3 It complements standards already issued by NICE on stroke and angina in respect of cardiovascular disease.4,5 Implementation of the five quality statements in QS52 represents a significant challenge for service providers, healthcare practitioners, and commissioners in terms of the resources, equipment, service provision, and appropriate training needed. The vast majority of patients with PAD can be managed in primary care, with only 5%–10% of individuals developing critical limb ischaemia, and fortunately no more than 1%–2% (although 5% of people with diabetes) undergoing lower limb amputation.3 Peripheral arterial disease is now firmly established in the quality and outcomes framework (QOF) following its inclusion as a clinical domain in 2012/13 and in subsequent updates. The first three of the five NICE quality statements (see Table 1) are particularly relevant to primary care.3

Table 1: Quality standard for peripheral arterial disease 2
No. Quality statement
1 People who have symptoms of, or who are at risk of developing, peripheral arterial disease (PAD) are offered a clinical assessment and ankle brachial pressure index (ABPI) measurement.
2 People with PAD are offered an assessment for cardiovascular comorbidities and modifiable risk factors.
3 People with intermittent claudication are offered a supervised exercise programme.
4 People with PAD being considered for revascularisation who need further imaging after a duplex ultrasound are offered magnetic resonance angiography (MRA).
5 People with intermittent claudication are offered angioplasty only when imaging has confirmed it is appropriate, after advice on the benefits of modifying risk factors has been given and after a supervised exercise programme has not improved symptoms.
NICE (2013) QS52. Quality standard for peripheral arterial disease. Available at www.nice.org.uk/guidance/QS52. Reproduced with permission.

Identification and assessment—statement 1

Patients with PAD invariably present with features of intermittent claudication. Statement 1 relates to a clinical assessment of these patients and of other people at risk of developing PAD. The diagnosis is confirmed by measuring the ankle brachial pressure index (ABPI), a practice recommended in NICE Clinical Guideline 1477 and now reflected in QS52.3 There is no requirement in the QOF6 for a healthcare practitioner to perform this measurement before adding the patient to the PAD register (PAD001) but there is a requirement (detailed under QS52, quality statement 1) for service providers and commissioners to supply adequate numbers of handheld Doppler ultrasound machines, and appropriately trained staff, to ensure accurate diagnosis and quantification of disease severity.3 In Scotland from April 2014, there is no requirement in the QOF to maintain a PAD register,8 further reducing the impact of the QOF.

NICE does not anticipate that implementing its recommendations on PAD diagnosis will involve significant costs. It has stated that any incremental resource needs are small compared with the benefits (improved quality of life, appropriate cost-effective management) of accurately identifying people with PAD.9 NICE feels that an ABPI can be performed by a practice nurse or podiatrist taking a clinical history, adding no more than 5 to 15 minutes to the time taken for the examination.9

Comorbidity assessment—statement 2

Statement 2 requires patients with PAD to be offered an assessment for cardiovascular comorbidities and modifiable risk factors. Peripheral arterial disease is a significant marker for both stroke and coronary heart disease (CHD), so many of these patients will be included in other QOF disease categories and attending relevant practice disease management clinics. Registry data continue to highlight this association, with recent data from the Reduction of Atherothrombosis for Continued Health (REACH) registry revealing that over two-thirds of patients with PAD have symptomatic CHD or stroke; these patients have the highest cardiovascular event rates, yet people with PAD tend to receive suboptimal risk-factor management, increasing the challenge for primary care.9

Smoking has traditionally been seen as the most important risk factor for patients with PAD and the provision of smoking cessation support and treatment remains in the 2014/15 QOF update (SMOK005) for these patients.6 Although it is especially important for people at high risk of cardiovascular disease not to smoke, there is no convincing evidence for improved cardiovascular outcomes or symptoms in patients with PAD as a result of smoking cessation advice.11

There does, however, remain good evidence for the use of antiplatelet therapy (PAD004) and also statin therapy, which all patients with PAD should receive.11

The clinical indicator to measure cholesterol levels of people with PAD and achieve a target level of 5 mmol/l or lower has, unfortunately, been retired in the 2014/15 QOF update (PAD003), as it has for CHD and stroke, but not for diabetes.6 It will be interesting to monitor whether this change will lead to lower uptake of statin therapy and in due course poorer outcomes in terms of vascular events.

Supervised exercise programmes—statement 3

The requirement for all patients with PAD to be offered a supervised 2-hour exercise programme every week for a 3-month period (standard 3) will be the most difficult of the statements to commission and make available. The exercise programme is recommended on the basis that it will improve pain-free walking distance and, more controversially, quality of life.

An update of the original Cochrane Review, which formed the basis of this advice, was published in August 2013 and revealed a significant improvement in maximal treadmill walking distance compared with non-supervised exercise therapy, with an overall effect size of 0.69 (95% CI 0.51 to 0.86) and 0.48 (95% CI 0.32 to 0.64) at 3 months and 6 months, respectively.12 This benefit was maintained at 12 months but did not have a significant effect on quality of life.

In August 2012, NICE estimated the cost of this exercise programme to be £273 per person.9 At that time, only 30% of people with claudication were offered a supervised exercise programme and the evidence that it reduced the risk of cardiovascular events was based only on the experience of the guideline development group members.9,11 NICE has acknowledged that the focus of PAD exercise programmes is different from that of exercise programmes designed for people with CHD9 but there is a unique opportunity for commissioners to explore innovative, menu-based programmes tailored to the individual’s disease category; these could cater not only for people with PAD but also for people requiring cardiac and pulmonary rehabilitation.


Imaging and angioplasty for intermittent claudication—statements 4 and 5

Statements 4 and 5 relate to appropriate imaging and revascularisation for patients with PAD where secondary care referral is indicated. The decision to refer is based on the individual clinical situation. NICE CG147 suggests that referral should be considered if supervised exercises have not led to a satisfactory improvement in symptoms.7 Critical limb ischaemia should be referred immediately and the treatment approach should be determined by involvement of the multidisciplinary vascular team. Unless service providers ensure an appropriate referral protocol for these patients, then determining the level of services that require commissioning will be extremely difficult.

Conclusion

The true cost to the NHS of a lower-limb amputation, including care in the first year, could be as high as £32,000 per person; it should be possible to make large savings by investing in relatively inexpensive interventions to help to avoid amputations.9 Similarly, appropriate risk-factor management of patients with PAD will reduce the risk of stroke and myocardial infarction. The benefits for patients are easy to see, and primary care has an important role in ensuring that the clinical standards in NICE QS52 are met as far as possible.

  • The percentage of patients with PAD who:
    • have had the diagnosis confirmed by ABPI measurement
    • have a blood pressure of 150/90 mmHg or less, a total cholesterol of
      5 mmol/l or less, and are taking an antiplatelet drug
  • The proportion of patients with PAD who are offered, start, and complete
    a supervised exercise programme.

PAD=peripheral arterial disease

  • PAD is important for commissioners as a disease in itself but also as a marker for heart disease and stroke, which cause major morbidity and mortality
  • QOF data can give an idea of incidence but prevalence is probably much higher now that many cases of PAD are diagnosed using Doppler assessment of peripheral limb ulceration
  • Effective risk-factor management in PAD, and pharmacotherapy with statins and antiplatelet agents, can reduce morbidity and healthcare costs from PAD and other vascular disease
  • Commissioners may wish to consider local enhanced services with practices for wound care and Doppler assessments that will increase the early diagnosis of PAD and prevent referral to community or specialist care
  • Supervised exercise programmes are effective in increasing pain-free walking distance on a treadmill but do not improve quality of life and are not proven to decrease subsequent morbidity. Commissioners therefore need to make local decisions on the value of investing in such programmes, alongside other priorities.

PAD=peripheral arterial disease

  1. NICE website. NICE quality standards. www.nice.org.uk/guidance/qualitystandards/qualitystandards.jsp (accessed 20 March 2014).
  2. Health and Social Care Act. Available at: www.legislation.gov.uk/ukpga/2012/7/contents/enacted (accessed 20 March 2014).
  3. NICE website. Peripheral arterial disease. Quality Standard 52. www.nice.org.uk/guidance/qs52 (accessed 20 March 2014).
  4. NICE website. Stable angina. Quality Standard 21. www.nice.org.uk/guidance/QS21 (accessed 20 March 2014).
  5. NICE website. Stroke. Quality Standard 2. www.nice.org.uk/guidance/QS2 (accessed 20 March 2014).
  6. NHS Employers. Summary of changes to QOF 2014/15—England. NHS Employers. Available at: www.nhsemployers.org/SiteCollectionDocuments/2014_15_Summary_of_QOF_changes_mh141113.pdf
  7. NICE. Lower limb peripheral arterial disease: diagnosis and management. Clinical Guideline 147. NICE, 2012. Available at: publications.nice.org.uk/lower-limb-peripheral-arterial-disease-diagnosis-and-management-cg147
  8. British Medical Association website. General practice contract changes 2014–2015. Scottish GMS contract 2014–2015. bma.org.uk/working-for-change/negotiating-for-the-profession/bma-general-practitioners-committee/general-practice-contract/contract-agreement-scotland/scotland-qof-changes
  9. NICE. Lower limb peripheral arterial disease. Costing report. NICE Clinical Guideline 147. NICE, 2012. Available at: www.nice.org.uk/guidance/CG147/CostingReport/pdf/English
  10. Valentijn T, Stolker R. Lessons from the REACH Registry in Europe. Curr Vasc Pharmacol 2012; 10 (6): 725–727.
  11. Scottish Intercollegiate Guidelines Network. Diagnosis and management of peripheral arterial disease. SIGN 89. Edinburgh: SIGN, 2006. Available at: www.sign.ac.uk/guidelines/fulltext/89/index.html
  12. Fokkenrood H, Bendermacher B, Lauret G et al. Supervised exercise therapy versus non-supervised exercise therapy for intermittent claudication. Cochrane Database Syst Rev 2013; 8: CD005263. G