CVS

CVS
د. حسين محمد جمعه
اختصاصي الامراض الباطنة
البورد العربي
كلية طب الموصل
2011

Management of hypertension: summary of NICE guidance

BMJ 2011;343:

This is one of a series of BMJ summaries of new guidelines based on the best available evidence; they highlight important recommendations for clinical practice, especially where uncertainty or controversy exists.
Hypertension is one of the most important preventable causes of death worldwide and one of the commonest conditions treated in primary care in the United Kingdom, where it affects more than a quarter of all adults and over half of those over the age of 65 years. This article summarises the most recent
recommendations from NICE on the management of hypertension,which updates the 2004 and 2006 clinical guidelines.

Recommendations

NICE recommendations are based on systematic reviews of best available evidence and explicit consideration of cost effectiveness. When minimal evidence is availablerecommendations are based on the Guideline Development
Group’s experience and opinion of what constitutes good practice.


Diagnosing hypertension
If blood pressure measured in the clinic is 140/90 mm Hg or higher:
-Take a second measurement during the consultation
-If the second measurement is substantially different from the first, take a third measurement
-Record the lower of the last two measurements as the clinic blood pressure.

If the clinic blood pressure is 140/90 mm Hg or higher, use ambulatory blood pressure monitoring to confirm the diagnosis of hypertension. This strategy will improve the accuracy of the diagnosis compared with current practice and was also shown to be cost effective—indeed, cost saving—for the NHS. (Updated recommendation)

When using ambulatory blood pressure monitoring to confirm a diagnosis of hypertension, ensure that at least two measurements an hour are taken during the person’s usual waking hours (for example, between 0800 and 2200).
Use the average value of at least 14 measurements taken during the person’s usual waking hours to confirm adiagnosis of hypertension.
(New recommendation)
[Based on prognostic and reliability or reproducibility studies
determined to be at low risk of bias]

If a person cannot tolerate ambulatory blood pressure monitoring, home blood pressure monitoring is a suitable alternative to confirm the diagnosis. (New recommendation)

[Based on a systematic review of randomised controlled trials ranging in quality from poor to good and on cost effectiveness evidence]

When using home blood pressure monitoring to confirm a diagnosis of hypertension:

-For each blood pressure recording, take two consecutive measurements, at least one minute apart and with the person seated, and-Record blood pressure twice daily, ideally in the morning and evening, and -Continue recording blood pressure for at least four days, ideally for seven days, and -Discard the measurements taken on the first day and use the average value of all the remaining measurements to confirm a diagnosis of hypertension.
(New recommendation)


[Based on prognostic and reproducibility studies determined to be at low risk of bias]

While waiting for a confirmed diagnosis of hypertension,

investigate target organ damage (such as left ventricular hypertrophy, chronic kidney disease, and hypertensive retinopathy) and formally assess cardiovascular risk. (New recommendation)
[Based on the experience and opinion of the GDG]

Use risk equations to assess cardiovascular risk—for

example, the Framingham risk calculator7 (as used in the Joint British Societies’ risk charts available in the British National Formulary and

Thresholds for intervention

If the person has severe hypertension (clinic blood pressure ≥180/110 mm Hg), consider starting antihypertensive drug treatment immediately, without waiting for the results of ambulatory or home blood pressure monitoring. (New recommendation)
[Based on the experience and opinion
of the GDG]
Offer lifestyle advice to people with hypertension at initial diagnosis and then periodically thereafter

[Based on the experience and opinion of the GDG]

Offer antihypertensive drug treatment to people aged under 80 years with stage 1 hypertension (that is, an average ambulatory or home blood pressure of ≥135/85 mm Hg and <150/95 mm Hg; a clinic blood pressure of ≥140/90 mm Hg and <160/100 mm Hg) and who have one or more of the following:
-Target organ damage
-Established cardiovascular disease
-Renal disease
-Diabetes
-A 10 year cardiovascular risk equivalent to ≥20%.
(Updated recommendation) [Based on systematic reviews and meta-analyses of low quality observational and low to high quality randomised controlled trials; prognostic studies determined to be at low risk of bias; and a blood pressure
equivalence study of low quality]


Offer antihypertensive drug treatment to people of any age with stage 2 hypertension (an average ambulatory or home blood pressure of ≥150/95 mm Hg; a clinic blood pressure ≥160/100 mm Hg) irrespective of the presence of target
organ damage, cardiovascular disease, renal disease, or the 10 year risk of cardiovascular disease.

For people aged under 40 years with stage 1 hypertension and no evidence of target organ damage, cardiovascular disease, renal disease or diabetes, consider seeking specialist evaluation for secondary causes of hypertension and a more detailed assessment of potential target organ
damage. This is because 10 year cardiovascular risk
assessments can underestimate the lifetime risk of
cardiovascular events in these younger people. (Updated recommendation)

[Based on systematic reviews and meta-analyses of low quality observational and low to high
quality randomised controlled trials; prognostic studies determined to be at low risk of bias; and a blood pressure equivalence study of low quality]

Blood pressure medication

The figure⇓ outlines an algorithm showing the four steps in the drug treatment of hypertension.
If blood pressure is not controlled by the treatment offered at each step, review medication to ensure that the treatment is at optimal or best tolerated doses before moving to the next step.

(Updated recommendation) [Based on the experience and opinion of the GDG]

For people aged 80 years and over, offer the same
antihypertensive drug treatment as for people aged 55-80 years, taking into account any comorbidities. (Updated recommendation)

[Based on a systematic review and meta-analysis including moderate to high quality

randomised controlled trials, and on cost effectiveness evidence]


Step 1
For people aged under 55 years, offer an angiotensin converting enzyme (ACE) inhibitor or a low cost angiotensin II receptor blocker (ARB). If an ACE inhibitor is prescribed and is not tolerated (for example, because of cough), offer an ARB. (Updated recommendation)

[Based on a low to high quality randomised controlled trial and on cost effectiveness evidence]

Do not combine an ACE inhibitor with an ARB to treat hypertension. This is not the most rational combination to reduce blood pressure and may result in more adverse events without any additional clinical benefit.
(Updated recommendation)

[Based low to high quality evidence from a randomised controlled trial]

For people aged over 55 years and black people of African
or Caribbean family origin of any age, offer a calcium channel blocker. If this is not suitable—for example,
because of oedema or intolerance—or if there is evidence of heart failure or a high risk of heart failure, offer athiazide-like diuretic.
(Updated recommendation)

[Based on a moderate to high quality randomised controlled trial and cost effectiveness evidence]

If diuretic treatment is to be started or changed, offer athiazide-like diuretic, such as chlortalidone (12.5-25.0 mg once daily) or indapamide (1.5 mg modified release once daily or 2.5 mg once daily), in preference to a conventional thiazide diuretic such as bendroflumethiazide or hydrochlorothiazide. (Updated recommendation)

[Based on moderate to very low quality evidence from randomised controlled trials]

For people who are already taking bendroflumethiazide or hydrochlorothiazide and whose blood pressure is stable and well controlled, continue treatment with the bendroflumethiazide or hydrochlorothiazide.
(Updated recommendation)

[Based on moderate to very low quality evidence from randomised controlled trials and on the
experience and opinion of the GDG]

Step 2

Offer a calcium channel blocker in combination with either an ACE inhibitor or an ARB.
(Updated recommendation)

[Based on evidence from a moderate quality randomised controlled trial]

If a calcium channel blocker is not suitable for step 2
treatment—for example, because of oedema or
intolerance—or if there is evidence of heart failure or a high risk of heart failure, offer a thiazide-like diuretic.

Step 3

If treatment with three drugs is needed, offer an ACE inhibitor or ARB, combined with a calcium channel blocker and a thiazide-like diuretic. (Updated recommendation)

[Based on moderate to very low quality evidence from randomised controlled trials and on the experience and opinion of the GDG]


Step 4 (Resistant hypertension)
If clinic blood pressure remains higher than 140/90 mm Hg after treatment with the optimal or best tolerated doses of the drug combination mentioned in step 3 (an ACE inhibitor or an ARB combined with a calcium channel blocker and a diuretic), regard this as resistant hypertension, and consider adding a fourth antihypertensive drug and/or seeking expert advice. (Updated recommendation)

[Based on low quality observational evidence]

For treatment of resistant hypertension:
-Consider further diuretic treatment with low dose spironolactone (25 mg once daily) if the blood potassium concentration is 4.5 mmol/L or lower. Use particular caution in people with a reduced estimated glomerular filtration rate because they have an increased risk of hyperkalaemia
-Consider higher dose thiazide-like diuretic treatment if the blood potassium concentration is higher than 4.5 mmol/L.

(Updated recommendation) [Based on low quality observational evidence]

If further diuretic treatment for resistant hypertension at step 4 is not tolerated or is contraindicated or ineffective, consider an α blocker or β blocker.
(Updated recommendation)
[Based on low quality observational studies]
If blood pressure remains uncontrolled with the optimal or maximum tolerated doses of four drugs, seek expert advice if not yet obtained. (Updated recommendation)

[Based on the experience and opinion of the GDG]

Monitoring blood pressure treatment
Use clinic blood pressure measurements to monitor the response to antihypertensive treatment with lifestyle modifications or drugs.
(Updated recommendation)


[Based on systematic reviews of very low to moderate quality randomised controlled trials, and cost effectiveness evidence]

For people identified as having a “white coat effect”—that is,a discrepancy of more than 20/10 mm Hg between clinic and average daytime ambulatory blood pressure or average home blood pressure measurements at the time of diagnosis—consider ambulatory or home blood pressure monitoring as an adjunct to clinic blood pressure measurements to monitor the response to antihypertensive treatment with lifestyle modification or drugs. (Updated recommendation)

[Based on systematic reviews and meta-analyses of very low to moderate quality randomised controlled trials]

Overcoming barriers

The recommendation that ambulatory blood pressure rather than clinic blood pressure measurements should be used to confirm the diagnosis of hypertension will have a profound impact on patient care by reducing the number who are incorrectly labelled as hypertensive and thus inappropriately prescribed antihypertensive treatment. Currently, only some primary care
practices have access to ambulatory blood pressure monitoring devices, with the rest having to access them through referral to secondary care.