Cardiovascular disease: what the guidelines say

The prevalence of cardiovascular disease, and the involvement of practice nurses in its prevention and management are so great that it is useful from time to time to go back to the guidelines to ensure best practice

The British Heart Foundation publishes regular updates of cardiovascular disease (CVD) statistics using information from across the globe. Their latest figures1 include the following headlines:

• CVD is the biggest killer in the UK, just ahead of cancer. In 2009 there were 180,000 deaths from CVD, of which 80,000 were due to coronary heart disease (CHD) and 49,000 due to cerebro-vascular accident (CVA). Of these, 46,000 deaths occurred prematurely, that is under age 75.
• About 150,000 people each year have a stroke and 103,000 have a heart attack. The UK prevalence of CVD is rising gradually, but the death rate from CVD has fallen by two thirds since 1980. There are 2.6 million people living with CVD.
• In 2009 the NHS cost of CVD was £9bn, but the total cost to the nation (lost production, benefits, care) was £19bn.

Looking at the prevalence of CVD risk factors in the UK:

• A third of adults have hypertension, of which only half is treated
• 60% of adults have a total cholesterol > 5mmol/l
• A quarter of adults are obese (BMI > 30Kg/m2)
• A fifth of adults smoke
• Less than half of adults get enough exercise (and this is on self-rating so is probably optimistic).

So CVD is an important area for both primary care and public health, and also therefore, policy makers.

Practice nurses get involved with CVD because most of the subgroups of CVD are chronic diseases, and are managed by nurses through chronic disease management clinics. In addition, a patient with one circulatory disease is also more at risk of having another, so (for example) patients with angina should also be monitored for hypertension. Because there are lots of different facets of CVD, an individual patient is best served by estimating their cardiovascular risk and treating accordingly.

THE 'FAMILY' OF CVD

Earlier this year, the Department of Health produced a report suggesting that CVD should be regarded as a family of illnesses.² The report was prompted by a widely circulated survey that suggested that the UK is not very good by the standard of comparable countries at managing CVD.³ The report is loaded with unfamiliar acronyms, and in its 10 recommendations looks to the NHS to treat patients with CVD properly, and to 'case find' those at high risk. None of this is new. No fresh clinical evidence is offered, and it might be argued that primary care is trying to do all these things anyway. Great hopes are held out for the NHS Health Check Programme.

However, this report does point out the interconnectedness of circulatory diseases, emphasising a central feature that they do cluster in some individuals. If you have a patient with one circulatory problem, it is a good idea to look for others. And so your response to Jim must be an honest one — 'because you have angina you are at increased risk of having all manner of other unpleasant diseases, and the risk can be reduced by appropriate management'.

Because they are important, CVD diseases have generated a lot of guidelines and reports. The goalposts keep shifting, but not as much as you might think. In primary care in England & Wales we are subject to two particular clinical masters — the National Institute of Health and Care Excellence (NICE) and the Quality and Outcomes Framework (QOF). In Scotland the guideline body is the Scottish Intercollegiate Guidelines Network (SIGN). As NICE is now responsible for developing the menu of indicators for QOF, it is not surprising that there is more convergence between them — nonetheless, some differences remain. We also retain some professional integrity: we will treat people with, or who are at risk of, CVD properly because it is our duty and a source of professional pride so to do. So what are the recent developments in the best management of CVD that we should be aware of?

HYPERTENSION

NICE last revised its guidance on hypertension 2011.⁴

Diagnosis

One of the most significant changes from the previous edition is that the days of the 'office' — i.e. surgery — blood pressure check are numbered. In general doctors are pretty rubbish at using a sphygmomanometer,5 and in any case you need 10-13 readings to get a result sufficiently accurate to inform treatment choices.⁶

If you get a reading of 140/90mmHg or more in the surgery, take another reading (or two more if the second reading is a lot lower — in a quarter of patients the reading is elevated by the 'white coat effect'7). If the average of the last two readings is more than 140/90 mmHg, then use ambulatory monitoring before a diagnosis is confirmed. Many practices now have the kit to do ambulatory monitoring, or a neighbouring practice will offer the service to the locality, and it is often the practice nurses who fit the monitorss, and ensure they are returned after use (they are quite expensive). If your patient can't get on with ambulatory monitoring, an option is to get them to take their own blood pressure. The equipment for this cannot be prescribed, but the modern machines are pretty reliable and relatively cheap. Recommendations for the best devices are available from the British Heart Foundation.⁸ Once the blood pressure question has been sown in your patient's mind he or she will often want to self-monitor anyway, so having a machine is of longer term relevance. Treatment thresholds for ambulatory or home monitoring are 135/85 mmHg with end-organ damage, or 150/95 mmHg without.⁴

Remember, a diagnosis of hypertension is a life changing event and should not be made lightly.

Age

The NICE guidance does not suggest starting treatment in people over 80 years. The benefits of treating hypertension increase with age, but so also do the dangers of falls due to episodes of low blood pressure. For those already on treatment, a target of 150/90mmHg is recommended for those aged over 80, rather than the 140/90mmHg for everyone else.

Treatments

With the exception of patients with both hypertension and heart failure, the use of beta-blocking drugs has now been relegated to Division 4 of treatment (which is the 'when all else has failed' division). This change in recommendation was expected. Less widely-predicted was the abandonment of bendroflumethiazide as a drug of choice, with chlortalidone and indapamide (which is cheaper) having taken over as they have a stronger evidence base that they do some good.

There is some evidence that antihypertensive drugs work better if they are taken in the evening.⁹

Explaining risk

Raised blood pressure is only one of a number of risk factors for CVD. Treatment has side effects — lifestyle changes are difficult to sustain, if you look in the BNF all drug treatments have possible adverse effects. And even immaculately treated hypertension does not secure immortality. The National Prescribing Centre put it into context: If 100 people with hypertension are treated and controlled for 10 years, 80 people would not have had a heart attack or a stroke anyway; 15 people will have a stroke or a heart attack despite their blood pressure being controlled; only 5 will be prevented from having a CVD event.¹⁰

The QOF

The next time that politicians tell you that setting targets improves patient care, you could refer thim to reference 11: when QOF came in in 2004 and set targets for treated hypertension subject to financial reward, it made absolutely no difference to blood pressure control in the UK.¹¹

STROKE

The treatment of stroke in the UK continues to raise concerns in comparison with our neighbours in the developed world.¹² NICE produced guidance on the management of acute stroke in 2008,13 and SIGN followed up with guidance about rehabilitation in 2010.14

There has been a public awareness campaign using the FAST tool (Face, Arm, Speech, Time for hospital), based on the increasing evidence that thrombolysis using intravenous alteplase reduces the effects of a 'brain attack' as long as it is given promptly (once an intracranial bleed as a cause of the stroke has been excluded first by brain imaging — otherwise it makes things worse). So there is a 'window of opportunity' for intervention, meaning that the priority becomes getting patients suspected of having a stroke into hospital as quickly as possible.

Rehabilitation after stroke works best if it is led by specialists.¹⁴ After a stroke, patients get depressed, have pain and disability, and generally find adjusting to their new reality difficult. Practice nurses will be at the forefront of community monitoring, and this is yet another instance where communication and co-ordination with secondary care is crucial to secure the best outcome.

CORONARY HEART DISEASE

NICE published guidance on 'Chest pain of recent onset' in 2010,15 and on the 'Management of stable angina' in 2011.16

The chest pain guidance suggests immediate hospital transfer for people presenting with acute chest pain. If you have an ECG in the practice, do a tracing and send it with your patient, but only if doing so does not delay transfer. Supplementary oxygen is only useful if oxygen saturation is less than 94%, or 88% in those with known COPD. For those with stable chest pain, a risk assessment for CHD is suggested. Symptoms that make a diagnosis of CHD less likely are:

• Pain that is continuous or very prolonged
• Pain that is not related to activity
• Pain that is brought on by breathing
• Associated symptoms of dizziness, palpitations, tingling, difficulty swallowing.

Another take on this is the Marburg Heart Score.¹⁷ Score one point each for:

• Age over 65 (women) or 55 (men)
• Known CVD
• Patient assumes pain of heart origin
• Pain worse with exercise
• Pain not reproducible by pressing on the chest

This test uses a cut-off score of 3 or more, giving a sensitivity of 89% and a specificity of 63% for the symptoms being caused by CHD.

Such an emphasis on not sending patients with chest pain to hospital may appeal to purists and the Chancellor of the Exchequer, but will be scant comfort to the practice nurse confronted with a patient with chest pain at the surgery.

The guidance on angina suggests drug management using short-acting nitrates (e.g.GTN spray), then beta-blockers and/or a calcium channel blocker, and only then a long active nitrate or nicorandil.¹⁶

Lipids

NICE last issued guidance about lipid modification in 2008, which was dealt with in a previous article.¹⁸

Debate continues, however, about the level of CVD risk that should be treated. NICE still guides that a CVD risk of 20% in the next 10 years should prompt an attempt to lower cholesterol. NICE uses Quality Adjusted Life Years (QALY) — a calculation for assessing not only how long a medical intervention keeps someone alive, but also what sort of life the survivor is likely to have. According to NICE if a QALY costs less than £30,000 it is worth having, but if it costs more it isn't. But the relationship between cholesterol level and CVD is linear, so that lowering cholesterol secures some benefit for everyone, it's just that for some people the benefit is so tiny it is not worth having. If the threshold CVD risk for treatment with a statin was 10% and not 20%, an extra 5 million people in the UK could be prescribed a statin drug, and these are people who are free of CVD. It is estimated that such a step would prevent 10,000 CVD events a year and save 2000 lives.¹⁹ But fit people who pay their prescription charges, and develop muscle aches and liver problems because of taking their tablets might be less than impressed.

EXTENDED FAMILY

Lifestyle issues impact on the risk of CVD. In general obesity is getting worse, and lack of exercise is probably getting no better. Smoking is the only lifestyle success with smoking now being a habit for only 20% of adults.

The population continues to age, and this too is a potent CVD risk factor. This trend will not alter for the foreseeable future, and ironically is exacerbated by the efforts of the NHS to keep people alive longer.

Some pre-existing diseases make CVD more likely. The big one here is diabetes — also becoming more common with a fatter, more indolent and ageing population. The other is Chronic Kidney Disease, a problem only really addressed by primary care in the last few years, and now firmly established as a QOF targets.

The tendency for the illnesses contained under the umbrella of CVD to cluster in individual patients has resulted in the idea of the CVD 'family' — there is no new information, just a new way of looking at it.

CONCLUSION

CVD remains important because it still kills more people in the UK than anything else, imposes a heavy burden of incapacity, and because chronic disease management and treatment costs are likely to occupy practice nurses and politicians for many years yet.

REFERENCES

1. British Heart Foundation. Coronary Heart Disease Statistics 2012. http://www.bhf.org.uk/plugins/PublicationsSearchResults/DownloadFile.aspx?docid=508b8b91-1301-4ad7-bc7e-7f413877548b&version=-1&title=Coronary+Heart+Disease+Statistics+2012+&resource=G608 [Accessed 26.3.13]

2. Department of Health. Cardiovascular Disease Outcome Strategy. 2013 http://www.wp.dh.gov.uk/publications/files/2013/03/9387-2900853-CVD-Outcomes_web1.pdf. [Accessed 26.3.13]

3. Murray CJL et al. UK health performance: findings of the Global Burden of Disease Study 2010. The Lancet, 2013; 381: 997 — 1020.

4. NICE. Hypertension: clinical management of primary hypertension in adults (update). CG127. http://guidance.nice.org.uk/CG127 [Accessed 26.3.13]

5. Mant J & McMannus R. Measurement of blood pressure in primary care. BMJ 2011;342:d382

6. Warren R E, Marshall T et al. Variability of office, 24-hour ambulatory, and self-monitored blood pressure measurements. BJGP 2010;60:675-80.

7. Ritchie L D, Campbell N C & Murchie P. New NICE guidelines for hypertension. BMJ 2011;343:d5644

8. British Hypertension Society. Blood Pressure Monitors Validated for Home Use

http://www.bhsoc.org//index.php?cID=246 [Accessed 26.3.13]

9. Influence of circadian time of hypertension treatment on cardiovascular risk: results of the MAPEC study. Ramón C. Hermida, Diana E. Ayala, Artemio Mojón, José R. Fernández. Chronobiology International 2010; 27(8): 1629—1651.

10. Hypertension patient decision aid http://www.npc.nhs.uk/therapeutics/cardio/cd_hyper/resources/pda_hypertension.pdf [Accessed 26.3.13]

11. Serumaga B et al. Effect of pay for performance on the management and outcomes of hypertension in the United Kingdom: interrupted time series study. BMJ 2011;342:d108

12. O'Dowd A. UK lags behind similar countries in stroke services, report says. BMJ 2008;336:1094-5.

13. National Institute for Health and Clinical Excellence (NICE). Stroke CG68. 2008

14. Scottish Intercollegiate Guidelines Network (SIGN). Management of patients with stroke. Rehabilitation, prevention, and management of complications, and discharge planning. Guidance 118. 2010.

15. NICE. Chest pain of recent onset (CG95), 2010. Available at: http://www.nice.org.uk/guidance/cg95

16. NICE. Management of stable angina (CG126), 2011. Available at: http://guidance.nice.org.uk/CG126/NICEGuidance/pdf/English

17. Haasenritter J et al. Ruling out coronary heart disease in primary care. Br J Gen Pract 2011;DOI:110.3395/bjgp12X649106

18. Warren E. Lipid modification: a practical approach. Practice Nurse 5 September 2008.

19. Gallagher J. NHS 'should consider giving statins to healthy people' BBC News website 17 May 2012.