Hypertension

3.12 Cardiovascular health - covering BP management

After this talk you should;

Know how to measure blood pressure accurately and consistently

Know when to start and how to monitor drug treatment

Feel confident about when to consider secondary hypertension

Know when to refer patients for further investigation and management.

What is hypertension?

The world health organisation (WHO) and the international hypertension society defines hypertension as having a systolic blood pressure above 140 mm Hg, or a diastolic blood pressure above 90 mm Hg, or both,

on at least 3 separate occasions.

Hypertension remains underdiagnosed, undertreated and poorly controlled in the UK.

Prevalence in over 35s- 32% of Men- 27% of women

This increases with age- 33% of men and 25% of women aged 45-54 years have hypertension.- 73% of men and 64% of women aged ≥75 years have hypertension.

Screening for hypertensionAll adults should have their blood pressure measured, at least every five years up to the age of 80, and at least annually thereafter.

Epidemiology

Why is hypertension important

Risk factor for leading causes of deaths in the Western world

Each 2 mmHg rise in systolic blood pressure associated with;

- 7% increased risk of mortality from IHD- 10% increased risk of mortality from stroke

vascular and renal damage caused by untreated hypertension can culminate in a treatment-resistant state.

Data from therapeutic trials of antihypertensive drugs consistently show reductions in cardiovascular events and total mortality without adversely affecting quality of life.

How do patients come to clinical attention?

• Usually asymptomatic and detected opportunstically

• Alternatively, patients may present with complications

• In the UK, the Quality and Outcomes Framework sets goals linked to GPs’ remuneration encourages GPs to measure BP in asymptomatic patients

• Increased availability of home BP monitoring / blood pressure measurement in pharmacies

Diagnosing hypertension• Measure BP in both arms.

• If difference between arms >20 mmHg repeat• If difference between arms remains >20 mmHg on the 2nd measurement,

measure subsequent BPs in arm with higher reading

• If BP measured is 140/90 mmHg or higher:• Take second measurement • If second substantially different take a third• Record lower of the two measurements

• Either automated machine or manual method• If pule is irregular - always use manual• Record to the nearest 2 mmHg

• If the blood pressure is 140/90 mmHg or higher, offer ABPM to confirm the diagnosis of hypertension

• If a person is unable to tolerate ABPM, HBPM is a suitable alternative to confirm the diagnosis of hypertension.

• While waiting to confirm diagnosis, investigate target organ damage and assess cardiovascular risk

• Those with high normal values (130-139/85-89 mm Hg) should be checked annually.

Confirming the diagnosis

Ambulatory blood pressure monitoring

Ensure two measurements /hour taken during the person’s usual waking hoursUse the average value of at least 14 measurements to confirm the diagnosis.

Home blood pressure monitoring

Ensure that:• Two consecutive measurements are taken, at least 1 minute apart and with

the person seated• BP is recorded twice daily• BP 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 the diagnosis.

Stage 1 hypertension • Clinic blood pressure is 140/90 mmHg or higher and subsequent ABP daytime

average or 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.

Defining Hypertension

Risk factors for cardiovascular disease :• Age• Sex• Socioeconomic group• Smoking habits throughout the patient’s lifetime• Family history of cardiovascular disease• Personal history of diabetes, kidney disease, or elevated cholesterol.

Symptoms suggesting cardiac complications of hypertension (ischaemia, infarction, or congestive cardiac failure) :• Chest pain• Breathlessness• Ankle swelling• Palpitations.

You should also check for clinical features that may suggest secondary hypertension.

History

Look for signs of hypertensive complications:

• Fundoscopy• Observation of neck veins.• Assessment of the apex beat• Auscultation of the heart for murmurs• Auscultation of the lungs• Palpation of the radial, popliteal, and foot pulses.• Assessment of the ankles and sacrum• Auscultation of the carotid arteries

Clinical Examination

Look for complications or possible secondary hypertension:

• Urinalysis with dipstick testing

• A resting 12-lead electrocardiogram (ECG)

• Urea and electrolytes• Serum glucose (ideally fasting)• Serum lipid profile• Thyroid function tests• Glomerular filtration rate.

Investigations

Secondary hypertension

Around 5% of people with hypertension - high blood pressure is due to an underlying (secondary) disease.

Causes include: Chronic renal disease Cushing’s syndrome Primary aldosteronism Thyrotoxicosis Phaeochromocytoma.

Common clinical features include: Age younger than 30 Sudden worsening of hypertension Poor response to treatment.

Assessing cardiovascular risk

NICE recommends;● Using 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.

• Aged under 80 years with stage 1 hypertension 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% or greater.

• Any age with stage 2 hypertension

• 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.

Initiating treatment

Other considerations

● Malignant (accelerated) hypertension - severe hypertension (eg systolic >200 mm Hg, diastolic >130 mm Hg), encephalopathy or nephropathy, papilloedema and/or angiopathic haemolytic anaemia.

● Accelerated hypertension needs urgent (same day) assessment and treatment.

● Suspected phaeochromocytoma - Consider this diagnosis if there is labile or postural hypotension, headache, palpitations, pallor and profuse sweating - refer for urgent (same day) assessment.

● Hypertensive crisis - a systolic blood pressure (SBP) ≥180 mm Hg or a diastolic blood pressure (DBP) ≥120 mm Hg . Treatment should safely reduce BP.

● Immediate reduction in BP is required only in patients with acute end-organ damage

Drug treatment – General principles

● If possible, offer drugs taken only once a day

● Prescribe non-proprietary drugs if these are appropriate and minimise cost

● Offer people with isolated systolic hypertension the same treatment as people with both raised systolic and diastolic blood pressure

● Offer people aged over 80 years the same antihypertensive drug treatment as people aged 55–80 years, taking into account any comorbidities.

● Do not combine an ACE inhibitor with an angiotensin II receptor blocker (ARB).

• Ask people about their diet and exercise patterns, and promote lifestyle changes - 30 mins brisk exercise a day, (DASH)

• Weight loss

• Alcohol consumption - limit intake to 21/14 units a week

• Discourage excessive consumption of coffee and other caffeine-rich products

• Encourage people to keep their salt intake low

• Offer people who smoke advice and help to stop smoking

• It is not recommended that primary care teams provide relaxation therapies routinely

• Do not offer calcium, magnesium or potassium supplements as a method for reducing blood pressure

Lifestyle interventions

• under 55 years – ACE inhibitor or a low-cost ARB.

• Over 55 or Afro-Carribean of any age - Calcium channel blocker

• 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.

• If diuretic treatment is to be initiated or changed, offer a thiazidelike diuretic, such as chlortalidone or indapamidE in preference to a conventional thiazide diuretic such as bendroflumethiazide or hydrochlorothiazide.

• 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.

Step 1 treatment

Step 2 treatment

- If blood pressure is not controlled by step 1 treatmentOffer with a CCB in combination with either an ACE inhibitor or ARBIf a CCB is not suitable , offer a thiazide-like diuretic (CCB intolerance, or if there is evidence of heart failure or a high risk of heart failure).

For black people of African or Caribbean family origin:Consider an ARB in preference to an ACE inhibitor, in combination with a CCB

Step 3 treatment

Before considering step 3 treatmentreview medication to ensure step 2 treatment is at optimal or best tolerated doses

Combination of three drugs:ACE inhibitor or angiotensin II receptor blocker,Calcium-channel blockerAnd Thiazide-like diuretic should be used

Step 4 treatment

If BP 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 & Or ( Alpha blocker or B-Blocker and seek expert advice )

Spironolactone (25 mg Od) if Potassium level is 4.5 mmol/l or lower. (Caution in pts with reduced GFR increased risk of hyperkalemia.)

Consider higher-dose thiazide-like diuretic treatment if the blood potassium level is higher than 4.5mmol/l. (monitor Na , K, Renal function within one month & repeat as required.) 

If BP uncontrolled with optimal or maximal tolerated doses of four drugs, Seek expert Advice

Clinical Blood pressure:

• People aged under 80 years: lower than 140/90 mm Hg• People aged over 80 years: lower than 150/90 mm Hg

Daytime average APBM OR average HBPM blood pressure during persona's usual waking hours.

• People aged under 80 years: lower than 135/85 mm Hg• People aged over 80 years: lower than 145/85 mm Hg

lower BP targets are recommended for diabetics;

• Type 1 diabetes: <135/85mmHg, or <130/80mmHg with nephropathy• Type 2 diabetes: <140/80mmHg, or <135/75mmHg if microalbuminuria or

proteinuria is present

BP targets

Urgent treatment needed: accelerated hypertension, severe hypertension (>220/>120 mm Hg) or impending complications (eg TIA, LVF).

Possible underlying cause: low K+, Na+ elevated (possible Conn's syndrome); elevated creatinine, proteinuria or haematuria; sudden onset or rapidly worsening or resistant hypertension (ie needs >3 drugs); young age: patient aged <20 years, or <30 years needing treatment.

Therapeutic problems: multiple drug intolerance or contra-indications, persistent noncompliance or treatment refusal (the reluctant hypertensive).

Special situations: hypertension in pregnancy, unusual blood pressure (BP) variability.

Indication for specialist referral

Please collect a question sheet and get into groups of 3

Question 1

A 65 year old woman who is newly diagnosed with hypertension attends your morning surgery for initial assessment. Which of the following is NOT recommended as part of the initial assessment of a patient with hypertension?

A - Measurement of weight, height, and waist circumference

B - Resting 12-lead ECG

C - Dipstick urinalysis

D - Full blood count

E - Urea and electrolytes

Question 1 – Answer

D – Full Blood count

Question 2

What are current recommendations for choosing sphygmomanometer cuffs?

A - The size of the cuff doesn’t matter: you should use the cuff that appears to be in the best condition

B - You should chose the cuff based on the patient’s arm circumference: the rubber bladder within the cuff should have a length of 80% of the arm circumference and a width of 40% of the arm circumference

C- You should chose the cuff based on the patient’s arm circumference: the rubber bladder within the cuff should have a length of 40% of the arm circumference and a width of 20% of the arm circumference

D - You should chose the cuff based on the patient’s arm circumference: the rubber bladder within the cuff should have a length of 120% of the arm circumference and a width of 80% of the arm circumference

Question 2 - Answer

B : You should chose the cuff based on the patient’s arm circumference: the rubber bladder within the cuff should have a length of 80% of the arm circumference and a width of 40% of the arm circumference

Most manufacturers and the NICE guidelines recommend that the rubber bladder within the cuff be around 40% of the patient’s arm circumference in width and 80% of the arm circumference in length. Using a bladder that is too small may overestimate blood pressure, using one that is too large will underestimate it.

Question 3

You see a 45 year old man in the clinic. He reports headaches and palpitations and is worried because both his parents had “high blood pressure.” You take his blood pressure and it is 155/98 mm Hg. How should you confirm or refute a diagnosis of hypertension in this patient?

A. The diagnosis is made by the blood pressure reading you have taken

B. This patient will require 24 hour ambulatory blood pressure monitoring

C. You should take a second reading after five minutes’ rest. If it is >140/90 mm Hg the diagnosis is confirmed

D. You should ask the patient to return weekly for the next two weeks for further readings. If these three readings are all >140/90 mm Hg the diagnosis is confirmed

Question 3 - Answer

B : This patient will require 24 hour ambulatory blood pressure monitoring

Recent national guidelines recommend that you offer all patients with a clinic reading of greater than 140/90 mm Hg ambulatory blood pressure monitoring (ABPM) to confirm the diagnosis. Home blood pressure monitoring (HBPM) with an ambulatory device is an acceptable alternative in patients intolerant of ABPM.

Question 4

About what percentage of adults are hypertensive, as defined by WHO and the International Society of Hypertension (blood pressure >140/90 mm Hg)?

●A – 5%

●B – 10%

●C – 25%

●D - 40%

Question 4 - Answer

D : 40%

According to the Heart of England Survey, 40% of adults in England have a blood pressure sustained at greater than 140/90 mm Hg, and would therefore be classified as hypertensive according to the WHO definition of hypertension

Question 5

You see a 47 year old woman for her first review appointment after being diagnosed with mild hypertension. She is keen to avoid drug treatment. Which one of the following statements about effective lifestyle measures is correct?

A. They can lower blood pressure as much as a single antihypertensive agent

B. They are more effective than beta blockers at reducing blood pressure

C. They usually avoid the need for drug therapy

D. They can be instituted effectively without good quality written information

E. They can be discontinued if drug therapy is begun

Question 5 - Answer

A : They can lower blood pressure as much as a single antihypertensive agent

Evidence from clinical trials suggests that effective and sustained lifestyle measures (weight reduction, exercise, dietary changes) can lower blood pressure as much as a single antihypertensive agent.

Question 6

You have been seeing a 39 year old Afro-Caribbean woman in the clinic for high blood pressure for several months. The most recent reading on ambulatory blood pressure monitorings 155/97 mm Hg. Her only other past medical history is two episodes of gout. She does not takeallopurinol. According to evidence based guidance which drug should you offer her first?

A. A calcium channel blocker

B. A beta blocker

C. A thiazide diuretic

D. An alpha blocker

Question 6 - Answer

A : A calcium channel blocker

Afro-Caribbean patients are at increased risk of hypertension and hypertensive complications.

For this reason, national guidelines recommend treating Afro-Caribbean patients younger than 55 the same as other patients older than 55.

First choice therapy for this patient would be a calcium channel blocker. This patient’s past history of gout means that thiazides should be used with caution because they may provoke a further episode.

Question 7

You see the same 39 year old Afro-Caribbean woman eight weeks after starting a calcium channel blocker. The dose of the calcium channel blocker had been increased at four weeks to the maximum recommended daily dose. She is feeling well and has experienced no side effects. Her most recent blood pressure measurement on ambulatory blood pressure monitoring (ABPM) was 148/96 mm Hg. What should you should now?

●A - Substitute the calcium channel blocker for an alpha blocker

●B - Refer to a hypertension specialist

●C - Add an ACE inhibitor

●D - Add a beta blocker

●E - Continue and recheck the blood pressure in six months

Question 7 - Answer

C : Add an ACE inhibitor

For this patient, step 2 of the algorithm would support adding an ACE inhibitor or an ARB if ACE inhibitors are not tolerated.

Question 8

You see a 49 year old white man in the clinic and you confirm that he has stage II ( ≥150/95 mm Hg) hypertension on ambulatory blood pressure monitoring. He is otherwise well. According to evidence based guidance which drug should you offer him first?

A. An ACE inhibitor

B. An alpha blocker

C. A thiazide diuretic

D. A calcium channel blocker

E. A combined preparation

Answer question 8

A : An ACE inhibitor

According to national guidelines, if you are starting drug treatment in this patient you should begin with an ACE inhibitor. [5] If the patient cannot tolerate ACE inhibitors or if he has contraindications, the alternative treatment of choice would be an ARB.

Question 9

You have made a diagnosis of hypertension in a patient several weeks ago and started treatment, initially with an ACE inhibitor. Which of the following clinical features should most make you consider that the patient has secondary hypertension?

A. The patient is 57 and had normal blood pressure measured four years ago

B. The patient’s blood pressure responds poorly to treatment, despite escalating up the A/CD protocol

C. The patient’s serum potassium is 4.9 mmol/l (reference range 3.5-5.1 mmol/l)

D. The patient’s serum creatinine fell after starting treatment

Question 9 - Answer

B : The patient’s blood pressure responds poorly to treatment, despite escalating up the A/CD protocol

Clinical features that suggest secondary, as opposed to essential, hypertension are:

• Age younger than 30• Sudden deterioration of hypertension• Poor response to drug treatment.

Question 10

You see a 55 year old man in the clinic for a routine check up. He does not report any symptoms, although he says that things have become stressful in work recently due to several colleagues losing their jobs. As part of your examination you take his blood pressure, which is 223/121 mm Hg. You repeat the blood pressure measurement later in the consultation and obtain a similar result. Fundoscopy is normal. What is the most important thing you should you do next?

A. Estimate the 10 year risk of cardiovascular disease using a risk chart or risk chart computer programme to help guide treatment

B. Confirm the reading over one to two weeks before you consider treatment

C. Begin treatment immediately

D. Give the patient an intravenous bolus of methyldopa

Question 10 - Answer

C : Begin treatment immediately

This is the course of action recommended by evidence based guidelines. This level of hypertension is particularly severe and requires urgent treatment.

Question 11

You review an 82-year-old woman in clinic. Last month she had a one-off blood pressure reading of 150/92 mmHg and was offered ambulatory blood pressure monitoring. This shows an average reading of 146/94 mmHg. She has no significant past medical history of note other than hypothyroidism. Her 10-year cardiovascular risk is calculated to be 16%. What is the most appropriate management?

A. Arrange further ambulatory blood pressure monitoringB. Start a thiazide-type diureticC. Give lifestyle advice and repeat blood pressure in 6 monthsD. Start an ACE inhibitorE. Start a calcium channel blocker

Question 11 - Answer

C. Give lifestyle advice and repeat blood pressure in 6 months

NICE now only recommend diagnosing people over the age of 80 years as hypertensive if they have stage 2 hypertension (ABPM daytime average or HBPM average BP >= 150/95 mmHg).

Remember that the diagnostic criteria are different from the blood pressure targets once treatment has started, which for people over the age of 80 years are: clinic readings < 150/90 mmHg ABPM/HBPM < 145/85 mmHg

Question 12 – List 1,2 and 3

Question 12 - Answer

1=2=3=

Question 13

A 72-year-old man is started on amlodipine 5mg od for hypertension. He has no other past medical history of note and routine bloods (including fasting glucose) and ECG were normal.

What should his target blood pressure be once on treatment?

A. 130/80 mmHgB. 140/80 mmHgC. 140/85 mmHgD. 140/90 mmHgE. 150/90 mmHg

Question 13 - Answer

B - Blood pressure target (based on clinic readings) for patients < 80 years - 140/90 mmHg

The NICE target differs from the Quality and Outcomes Framework (QOF) indicator for GPs working in England, which specify a target below 150/90 mmHg.

Question 14

A 60-year-old man type 1 diabetes mellitus comes for review. He has recently had laser therapy to treat proliferative retinopathy. What should his target blood pressure be?

A. < 125/75 mmHgB. < 130/80 mmHgC. < 140/85 mmHgD. < 140/90 mmHgE. < 140/80 mmHg

Question 14 - Answer

B - the blood pressure target for diabetics is 140/80 mmHg. If there is end-organ damage the target is 130/80 mmHg

Question 15

Which one of the following statements regarding the diagnosis of hypertension is true?

A. Home BP monitoring is superior and should be offered in preference to ambulatory blood pressure monitoring

B. Home BP monitoring should be performed twice a day for at least 4 weeks

C. Stage 2 hypertension is defined by clinic readings >= 140/90 mmHg

D. A one-off BP reading of 148/88 mmHg in an otherwise well 74-year-old can be ignored

E. When assessing home BP monitoring the first day readings should be discarded

Question 15 - Answer

E. When assessing home blood pressure monitoring the first day readings should be discarded

Question 16

You are evaluating a patient with suspected orthostatic syncope. What change in blood pressure upon standing for 3 minutes would be considered diagnostic for postural hypotension?

A. Symptomatic or asymptomatic fall in systolic BP > 30 mmHg or diastolic BP > 20 mmHg

B. Symptomatic fall in systolic BP > 30 mmHg or diastolic BP > 20 mmHg

C. Symptomatic or asymptomatic fall in systolic BP > 30 mmHg or diastolic BP > 10 mmHg

D. Symptomatic fall in systolic BP > 20 mmHg or diastolic BP > 10 mmHg

E. Symptomatic or asymptomatic fall in systolic BP > 20 mmHg or diastolic BP > 10 mmHg

Question 16 - Answer

D. Symptomatic fall in systolic BP > 20 mmHg or diastolic BP > 10 mmHg

Question 17

You review an 81-year-old man with regards to his hypertensive therapy. He is currently taking a combination of losartan and amlodipine which is failing to keep his blood pressure within target.

What is the most appropriate next step assuming he has no relevant contraindications?

A. Add indapamide MR 1.5mg od

B. Add atenolol 50mg od

C. Add ramipril 1.25mg od

D. Add doxazosin 1mg od

E. Add bendroflumethiazide 2.5mg od

Question 17 - Answer

A - Indapamide

NICE now advise using alternatives to bendroflumethiazide. Patients already taking bendroflumethiazide should however not be switched over to alternative thiazide-type diuretics.

This patient is taking an angiotensin 2 receptor blocker (losartan), possibly due to having problems with ACE inhibitor therapy previously, for example a dry cough. Patients should not normally take an ACE inhibitor and A2RB at the same time.

Question 18Side effects of anti-hypertensive drugs;

● Hyponatraemia

● Reduced seizure threshold

● Hypocalcaemia

● Cold peripheries

● Drug induced lupus

● Hypernatraemia

● Ankle oedema

For each of the following drugs choose the side-effect most characteristically associated with it;

● 1. Amlodopine

● 2. Bendroflumethiazide

● 3. Atenolol

Question 18 – Answer

1 – Ankle oedema

2 – Hyponatraemia

3 – Cold peripheries