Note from the National Guideline Clearinghouse (NGC): The original 2004 guideline was developed by the Newcastle Guideline Development and Research Unit. The guideline was updated by the National Clinical Guideline Centre (NCGC) (formerly the National Collaborating Centre for Chronic Conditions [NCC-CC]) in collaboration with the British Hypertension Society (BHS) in 2006 and 2011. See the "Availability of Companion Documents" field for the full version of this guidance.
In this guideline the following definitions are used.
- Stage 1 hypertension: Clinic blood pressure is 140/90 mmHg or higher and subsequent ambulatory blood pressure monitoring (ABPM) daytime average or home blood pressure monitoring (HBPM) average blood pressure is 135/85 mmHg or higher.
- Stage 2 hypertension: Clinic blood pressure is 160/100 mmHg or higher and subsequent ABPM daytime average or HBPM average blood pressure is 150/95 mmHg or higher.
- Severe hypertension: Clinic systolic blood pressure is 180 mmHg or higher or clinic diastolic blood pressure is 110 mmHg or higher.
Measuring Blood Pressure (BP)
Healthcare professionals taking blood pressure measurements need adequate initial training and periodic review of their performance. 
Because automated devices may not measure blood pressure accurately if there is pulse irregularity (for example, due to atrial fibrillation), palpate the radial or brachial pulse before measuring blood pressure. If pulse irregularity is present, measure blood pressure manually using direct auscultation over the brachial artery. [new 2011]
Healthcare providers must ensure that devices for measuring blood pressure are properly validated, maintained, and regularly recalibrated according to manufacturers' instructions. 
When measuring blood pressure in the clinic or in the home, standardise the environment and provide a relaxed, temperate setting, with the person quiet and seated, and their arm outstretched and supported. [new 2011]
If using an automated blood pressure monitoring device, ensure that the device is validated* and an appropriate cuff size for the person's arm is used. [new 2011]
*A list of validated blood pressure monitoring devices is available on the British Hypertension Society's Web site . The British Hypertension Society is an independent reviewer of published work. This does not imply any endorsement by NICE.
In people with symptoms of postural hypotension (falls or postural dizziness):
- Measure blood pressure with the person either supine or seated
- Measure blood pressure again with the person standing for at least 1 minute prior to measurement. [2004, amended 2011]
If the systolic blood pressure falls by 20 mmHg or more when the person is standing:
- Review medication
- Measure subsequent blood pressures with the person standing
- Consider referral to specialist care if symptoms of postural hypotension persist. [2004, amended 2011]
When considering a diagnosis of hypertension, measure blood pressure in both arms.
- If the difference in readings between arms is more than 20 mmHg, repeat the measurements.
- If the difference in readings between arms remains more than 20 mmHg on the second measurement, measure subsequent blood pressures in the arm with the higher reading. [new 2011]
If blood pressure measured in the clinic is 140/90 mmHg 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. [new 2011]
If the clinic blood pressure is 140/90 mmHg or higher, offer ambulatory blood pressure monitoring (ABPM) to confirm the diagnosis of hypertension. [new 2011]
If a person is unable to tolerate ABPM, home blood pressure monitoring (HBPM) is a suitable alternative to confirm the diagnosis of hypertension. [new 2011]
If the person has severe hypertension, consider starting antihypertensive drug treatment immediately, without waiting for the results of ABPM or HBPM. [new 2011]
While waiting for confirmation of a diagnosis of hypertension, carry out investigations for target organ damage (such as left ventricular hypertrophy, chronic kidney disease and hypertensive retinopathy) (see 'Assessing Cardiovascular Risk and Target Organ Damage' below) and a formal assessment of cardiovascular risk using a cardiovascular risk assessment tool (see 'Assessing Cardiovascular Risk and Target Organ Damage' below). [new 2011]
If hypertension is not diagnosed but there is evidence of target organ damage such as left ventricular hypertrophy, albuminuria or proteinuria, consider carrying out investigations for alternative causes of the target organ damage. [new 2011]
If hypertension is not diagnosed, measure the person's clinic blood pressure at least every 5 years subsequently, and consider measuring it more frequently if the person's clinic blood pressure is close to 140/90 mmHg. [new 2011]
When using ABPM to confirm a diagnosis of hypertension, ensure that at least two measurements per hour are taken during the person's usual waking hours (for example, between 08:00 and 22:00). Use the average value of at least 14 measurements taken during the person's usual waking hours to confirm a diagnosis of hypertension. [new 2011]
When using HBPM to confirm a diagnosis of hypertension, ensure that:
- For each blood pressure recording, two consecutive measurements are taken, at least 1 minute apart and with the person seated and
- Blood pressure is recorded twice daily, ideally in the morning and evening and
- Blood pressure recording continues for at least 4 days, ideally for 7 days.
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 2011]
Refer the person to specialist care the same day if they have:
- Accelerated hypertension, that is, blood pressure usually higher than 180/110 mmHg with signs of papilloedema and/or retinal haemorrhage or
- Suspected phaeochromocytoma (labile or postural hypotension, headache, palpitations, pallor and diaphoresis). [2004, amended 2011]
Consider the need for specialist investigations in people with signs and symptoms suggesting a secondary cause of hypertension. [2004, amended 2011]
Assessing Cardiovascular Risk and Target Organ Damage
For the National Institute for Health and Clinical Excellence (NICE) guidance on the early identification and management of chronic kidney disease see Chronic kidney disease (NICE clinical guideline 73).
Use a formal estimation of cardiovascular risk to discuss prognosis and healthcare options with people with hypertension, both for raised blood pressure and other modifiable risk factors. 
Estimate cardiovascular risk in line with the recommendations on Identification and assessment of cardiovascular disease (CVD) risk in Lipid modification (NICE clinical guideline 67).* 
*Clinic blood pressure measurements must be used in the calculation of cardiovascular risk.
For all people with hypertension offer to:
- Test for the presence of protein in the urine by sending a urine sample for estimation of the albumin:creatinine ratio and test for haematuria using a reagent strip.
- Take a blood sample to measure plasma glucose, electrolytes, creatinine, estimated glomerular filtration rate, serum total cholesterol and HDL cholesterol.
- Examine the fundi for the presence of hypertensive retinopathy.
- Arrange for a 12-lead electrocardiograph to be performed. [2004, amended 2011]
Lifestyle advice should be offered initially and then periodically to people undergoing assessment or treatment for hypertension. 
Ascertain people's diet and exercise patterns because a healthy diet and regular exercise can reduce blood pressure. Offer appropriate guidance and written or audiovisual materials to promote lifestyle changes. 
Relaxation therapies can reduce blood pressure and people may wish to pursue these as part of their treatment. However, routine provision by primary care teams is not currently recommended. 
Ascertain people's alcohol consumption and encourage a reduced intake if they drink excessively, because this can reduce blood pressure and has broader health benefits. 
Discourage excessive consumption of coffee and other caffeine-rich products. 
Encourage people to keep their dietary sodium intake low, either by reducing or substituting sodium salt, as this can reduce blood pressure. 
Do not offer calcium, magnesium or potassium supplements as a method for reducing blood pressure. 
Offer advice and help to smokers to stop smoking. 
A common aspect of studies for motivating lifestyle change is the use of group working. Inform people about local initiatives by, for example, healthcare teams or patient organisations that provide support and promote healthy lifestyle change. 
Initiating and Monitoring Antihypertensive Drug Treatment, Including Blood Pressure Targets
Offer antihypertensive drug treatment to people aged under 80 years with stage 1 hypertension who have one or more of the following:
- Target organ damage
- Established cardiovascular disease
- Renal disease
- A 10-year cardiovascular risk equivalent to 20% or greater [new 2011]
Offer antihypertensive drug treatment to people of any age with stage 2 hypertension. [new 2011]
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 of 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 people. [new 2011]
Monitoring Treatment and Blood Pressure Targets
Use clinic blood pressure measurements to monitor the response to antihypertensive treatment with lifestyle modifications or drugs. [new 2011]
Aim for a target clinic blood pressure below 140/90 mmHg in people aged under 80 years with treated hypertension. [new 2011]
Aim for a target clinic blood pressure below 150/90 mmHg in people aged 80 years and over, with treated hypertension. [new 2011]
For people identified as having a 'white-coat effect'*, consider ABPM or HBPM as an adjunct to clinic blood pressure measurements to monitor the response to antihypertensive treatment with lifestyle modification or drugs. [new 2011]
When using ABPM or HBPM to monitor the response to treatment (for example, in people identified as having a 'white-coat effect'* and people who choose to monitor their blood pressure at home), aim for a target average blood pressure during the person's usual waking hours of:
- Below 135/85 mmHg for people aged under 80 years
- Below 145/85 mmHg for people aged 80 years and over [new 2011]
*A discrepancy of more than 20/10 mmHg between clinic and average daytime ABPM or average HBPM blood pressure measurements at the time of diagnosis.
Choosing Antihypertensive Drug Treatment
Where possible, recommend treatment with drugs taken only once a day. 
Prescribe non-proprietary drugs where these are appropriate and minimise cost. 
Offer people with isolated systolic hypertension (systolic blood pressure 160 mmHg or more) the same treatment as people with both raised systolic and diastolic blood pressure. 
Offer people aged 80 years and over the same antihypertensive drug treatment as people aged 55–80 years, taking into account any comorbidities. [new 2011]
Offer antihypertensive drug treatment to women of child-bearing potential in line with the recommendations on 'Management of pregnancy with chronic hypertension' and 'Breastfeeding' in the NICE guideline Hypertension in pregnancy. 
Step 1 Treatment
Offer people aged under 55 years step 1 antihypertensive treatment with 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 a low-cost ARB. [new 2011]
Do not combine an ACE inhibitor with an ARB to treat hypertension. [new 2011]
Offer step 1 antihypertensive treatment with a calcium-channel blocker (CCB) to people aged over 55 years and to black people of African or Caribbean family origin of any age. If a CCB 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 a thiazide-like diuretic. [new 2011]
If diuretic treatment is to be initiated or changed, offer a thiazide-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. [new 2011]
For people who are already having treatment with bendroflumethiazide or hydrochlorothiazide and whose blood pressure is stable and well controlled, continue treatment with the bendroflumethiazide or hydrochlorothiazide. [new 2011]
Beta-blockers are not a preferred initial therapy for hypertension. However, beta-blockers may be considered in younger people, particularly:
- Those with an intolerance or contraindication to ACE inhibitors and angiotensin II receptor antagonists or
- Women of child-bearing potential or
- People with evidence of increased sympathetic drive 
If therapy is initiated with a beta-blocker and a second drug is required, add a calcium-channel blocker rather than a thiazide-like diuretic to reduce the person's risk of developing diabetes. 
Step 2 Treatment
If blood pressure is not controlled by step 1 treatment, offer step 2 treatment with a CCB in combination with either an ACE inhibitor or an ARB.* [new 2011]
If a CCB 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. [new 2011]
For black people of African or Caribbean family origin, consider an ARB* in preference to an ACE inhibitor, in combination with a CCB. [new 2011]
*Choose a low-cost ARB.
Step 3 Treatment
Before considering step 3 treatment, review medication to ensure step 2 treatment is at optimal or best tolerated doses. [new 2011]
If treatment with three drugs is required, the combination of ACE inhibitor or angiotensin II receptor blocker, calcium-channel blocker and thiazide-like diuretic should be used. 
Step 4 Treatment
Regard clinic blood pressure that remains higher than 140/90 mmHg after treatment with the optimal or best tolerated doses of an ACE inhibitor or an ARB plus a CCB plus a diuretic as resistant hypertension, and consider adding a fourth antihypertensive drug and/or seeking expert advice. [new 2011]
For treatment of resistant hypertension at step 4:
- Consider further diuretic therapy with low-dose spironolactone (25 mg once daily)* if the blood potassium level 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 level is higher than 4.5 mmol/l. [new 2011]
*At the time of publication (August 2011), spironolactone did not have UK marketing authorisation for this indication. Informed consent should be obtained and documented.
When using further diuretic therapy for resistant hypertension at step 4, monitor blood sodium and potassium and renal function within 1 month and repeat as required thereafter. [new 2011]
If further diuretic therapy for resistant hypertension at step 4 is not tolerated, or is contraindicated or ineffective, consider an alpha- or beta-blocker. [new 2011]
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. [new 2011]
Patient Education and Adherence to Treatment
Provide appropriate guidance and materials about the benefits of drugs and the unwanted side effects sometimes experienced in order to help people make informed choices. 
People vary in their attitudes to their hypertension and their experience of treatment. It may be helpful to provide details of patient organisations that provide useful forums to share views and information. 
Provide an annual review of care to monitor blood pressure, provide people with support and discuss their lifestyle, symptoms and medication. 
Because evidence supporting interventions to increase adherence is inconclusive, only use interventions to overcome practical problems associated with non-adherence if a specific need is identified. Target the intervention to the need. Interventions might include:
- Suggesting that patients record their medicine-taking
- Encouraging patients to monitor their condition
- Simplifying the dosing regimen
- Using alternative packaging for the medicine
- Using a multi-compartment medicines system
(This recommendation is taken from 'Medicines adherence' [see the NICE guideline Medicines adherence. Involving patients in decisions about prescribed medicines and supporting adherence ].)