Hypertension:
management
NICE published updated guidelines for the management of hypertension in 2011. Some of the key changes include:
- classifying hypertension into stages
- recommending the use of ambulatory blood pressure
monitoring (ABPM) and home blood pressure monitoring (HBPM)
- calcium channel blockers are now considered
superior to thiazides
- bendroflumethiazide is no longer the thiazide of
choice
Blood pressure classification
This becomes relevant later in some of the management decisions that NICE advocate.
Stage
|
Criteria
|
Stage
1 hypertension
|
Clinic
BP >= 140/90 mmHg and subsequent ABPM daytime average or HBPM average BP
>= 135/85 mmHg
|
Stage
2 hypertension
|
Clinic
BP >= 160/100 mmHg and subsequent ABPM daytime average or HBPM average BP
>= 150/95 mmHg
|
Severe
hypertension
|
Clinic
systolic BP >= 180 mmHg, or clinic diastolic BP >= 110 mmHg
|
 |
|
|
|
Flow chart showing simplified schematic
for diagnosis hypertension following NICE guidelines
Managing hypertension
Lifestyle advice should not be forgotten and is frequently tested in exams:
- a low salt diet is recommended, aiming for less
than 6g/day, ideally 3g/day. The average adult in the UK consumes around 8-12g/day
of salt. A recent BMJ paper* showed that lowering salt intake can have a
significant effect on blood pressure. For example, reducing salt intake by
6g/day can lower systolic blood pressure by 10mmHg
- caffeine intake should be reduced
- the other general bits of advice remain: stop
smoking, drink less alcohol, eat a balanced diet rich in fruit and
vegetables, exercise more, lose weight
ABPM/HBPM >= 135/85 mmHg (i.e. stage 1 hypertension)
- treat if < 80 years of age AND any of the
following apply; target organ damage, established cardiovascular disease,
renal disease, diabetes or a 10-year cardiovascular risk equivalent to 20%
or greater
ABPM/HBPM >= 150/95 mmHg (i.e. stage 2 hypertension)
- offer drug treatment regardless of age
For patients < 40 years consider specialist referral to exclude secondary causes.
 |
|
|
|
Flow chart showing the management of
hypertension as per current NICE guideliness
Step 1 treatment
- patients < 55-years-old: ACE inhibitor (A)
- patients >= 55-years-old or of Afro-Caribbean
origin: calcium channel blocker
Step 2 treatment
- ACE inhibitor + calcium channel blocker (A + C)
Step 3 treatment
- add a thiazide diuretic (D, i.e. A + C + D)
- NICE now advocate using either chlorthalidone
(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
NICE define a clinic BP >= 140/90 mmHg after step 3 treatment with optimal or best tolerated doses as resistant hypertension. They suggest step 4 treatment or seeking expert advice
Step 4 treatment
- consider further diuretic treatment
- if potassium < 4.5 mmol/l add spironolactone
25mg od
- if potassium > 4.5 mmol/l add higher-dose
thiazide-like diuretic treatment
- if further diuretic therapy is not tolerated, or
is contraindicated or ineffective, consider an alpha- or beta-blocker
Patients who fail to respond to step 4 measures should be referred to a specialist. NICE recommend:
If blood pressure remains uncontrolled with the optimal or maximum tolerated doses of four drugs, seek expert advice if it has not yet been obtained.
Blood pressure targets
Clinic
BP
|
ABPM
/ HBPM
|
|
Age
< 80 years
|
140/90
mmHg
|
135/85
mmHg
|
Age
> 80 years
|
150/90
mmHg
|
145/85
mmHg
|
New drugs
Direct renin inhibitors
- e.g. Aliskiren (branded as Rasilez)
- by inhibiting renin blocks the conversion of
angiotensinogen to angiotensin I
- no trials have looked at mortality data yet.
Trials have only investigated fall in blood pressure. Initial trials suggest
aliskiren reduces blood pressure to a similar extent as angiotensin
converting enzyme (ACE) inhibitors or angiotensin-II receptor antagonists
- adverse effects were uncommon in trials although
diarrhoea was occasionally seen
- only current role would seem to be in patients
who are intolerant of more established antihypertensive drugs
*BMJ 2013;346:f1325
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