Hypertension

Question 1

What is hypertension?

Answer 1

Hypertension is persistently raised arterial BP

Raised BP increases risk of cardiovascular disease

Question 2

What are the threshold value for diagnosing hypertension?

How is the diagnosis confirmed?

Answer 2

Clinic systolic BP >= 140mmHg or diastolic BP >=90mmHg or both

Diagnosis is confirmed by:

Ambulatory blood pressure monitoring (ABPM) or home blood pressure monitoring (HBPM)

Question 3

What is primary hypertension?

What is secondary hypertension?

Answer 3

Primary hypertension = no identifiable cause (90% of patients)

Secondary hypertension = known underlying cause i.e.
=> RENAL (most common 2ndary cause of HTN) i.e.
- chronic pyelonephritis,
- diabetic nephropathy,
- glomerulonephritis,
- polycystic kidney disease,
- renal cell carcinoma

=> ENDOCRINE i.e. primary

• hyperaldosteronism,
• phaeochromocytoma,
• Cushing’s syndrome,
• acromegaly,
• hypo/hyperthyroidism

=> VASCULAR i.e.

• coarctation of aorta,
• renal artery stenosis

=> DRUGS i.e.

• Alcohol
• Ciclosporin
• Cocaine
• Steroids
• Venlafaxine

Question 4

What is malignant (accelerated) hypertension?

Answer 4

Severe increase in blood pressure to 180/120 mmHg or higher (and often over 220/120 mmHg)

Signs of retinal haemorrhage and/or papilloedema (swelling of the optic nerve).

It is usually associated with new or progressive target organ damage.

Question 5

What is ‘white coat’ hypertension?

Answer 5

BP unusually raised in clinics but is normal when measured in ‘non-threatening’ situations.

A ‘white-coat’ effect is a discrepancy of >20/10 mmHg between clinic and average daytime ABPM or average HBPM blood pressure measurements at the time of diagnosis

Occurs in about 15–30% of the population

Question 6

What is masked hypertension?

Answer 6

Clinic BP is normal (less than 140/90 mmHg) but BP measurements are higher when taken outside the clinic using average daytime ABPM or average HBPM blood pressure measurements.

Question 7

What is the prevalence of hypertension?

Answer 7

Prevalence of hypertension in adults:
31% in men and 26% in women

Prevalence of hypertension rises to >50% in people aged over 60 years.

Globally, ~ 25% of adults have hypertension

Question 8

What are the risk factors of hypertension?

Answer 8

Non-modifiable Risk Factors:
1. Age — BP rises with advancing age

2. Sex — Up to about 65 years, women tend to have a lower BP than men. Between 65 to 74 years of age, women tend to have a higher blood pressure.
3. Ethnicity — Black African and Black Caribbean origin higher risk
4. Genetic factors
5. Social deprivation — people from the most deprived areas in England are 30% more likely to have hypertension than those from the least deprived.

Modifiable Risk Factors:

1. Lifestyle
   - Smoking,
   - Excessive alcohol consumption,
   - Excess dietary salt,
   - Obesity
   - Lack of physical activity
2. Anxiety and emotional stress — can raise BP due to increased adrenaline and cortisol levels.

Question 9

Hypertension increases the risk of which conditions?

Answer 9

1. Heart failure
2. Coronary artery disease
3. Stroke
4. Chronic Kidney Disease
5. Peripheral arterial disease
6. Vascular dementia
   * Hypertension is the single biggest risk factor for CVD and related disability => at least half of all heart attacks and strokes assoc. with HTN
   * With 2mmHg rise in systolic BP assoc. with 7% increased risk of mortality from ischaemic heart disease and 10% increased risk of mortality from stroke
   * Correction of high BP (lifestyle modifications or drug treatment) reduces the above health risks.

Question 10

What are the 3 stages of hypertension?

Answer 10

1. Stage 1 hypertension
   => clinic BP from 140/90 mmHg to 159/99 mmHg
   => subsequent ABPM daytime average or HBPM average BP ranging from 135/85 mmHg to 149/94 mmHg.
2. Stage 2 hypertension
   => clinic BP of >=160/100 mmHg - 180/120 mmHg
   => subsequent ABPM daytime average or HBPM average BP of >=150/95 mmHg.
3. Stage 3 or severe hypertension
   => clinic systolic BP of >180 mmHg
   => clinic diastolic BP of >120 mmHg

Question 11

Hypertension diagnosis pathway:

Clinic reading >=140/90mmHg

=> Offer ABPM or HBPM

1. If ABPM/HBPM under 135/85mmHg = not hypertensive, just monitor

Answer 11

2. If ABPM / HBPM >=135/85mmHg

=> Stage 1 hypertension

Treat if <80 years AND any of the following:

• Target organ damage
• Established CVD
• Renal disease
• Diabetes
• 10-year cardiovascular risk equivalent to 10% or greater

Offer drug treatment for HTN

3. If ABPM /HBPM >=150/95mmHg

=> Stage 2 hypertension

Treat all patients regardless of age.

Offer drug treatment for HTN

Question 12

How is a diagnosis of HTN confirmed?

Answer 12

ABPM / HBPM = confirms diagnosis of HTN.

Prevents over-diagnosis i.e. excludes white coat hypertension subgroup, as it is not true hypertension.

*ABPM = more accurate predictor of CVD than clinics readings

Question 13

Diagnosis of HTN:

NICE: Measure BP in both arms when considering a diagnosis of HTN

If the difference is > 20mmHg then REPEAT measurement

If BP remains >20mmHg then the higher BP out of the two arms should be recorded

*consider pathological causes of difference in arm BP i.e. supravascular aortic stenosis. ALWAYS listen to heart sounds

Answer 13

NICE: also recommends taking a second reading during the consultation if the first is >140/90.

=> Management dependent on the lower reading of the two ^

=> Offer ABPM / HBPM if BP >=140/90mmHg

Question 14

How does ABPM work?

Answer 14

1. At least 2 measurements per hour during the person’s usual waking hours (for example, between 08:00 and 22:00)
2. Use the average of at least 14 measurements
   * ABPM is a 24h blood pressure monitor

Question 15

If ABPM not tolerated or declined, HBPM should be offered.

How does HBPM work?

Answer 15

1. For each BP recording, two consecutive measurements need to be taken, at least 1 minute apart and with the person seated
2. BP should be recorded twice daily, ideally in the morning and evening
3. BP should be recorded for at least 4 days, ideally for 7 days
4. Discard the measurements taken on the first day and use the average value of all the remaining measurements

Question 16

What are the investigations for hypertension after diagnosis?

Answer 16

1. Urea & Electrolytes: check for renal disease, either as a cause or consequence of hypertension
2. HbA1c: check for co-existing diabetes mellitus - risk factor for CVD
3. Lipids: check for hyperlipidaemia - risk factor for CVD

To check for end-organ failure in newly diagnosed HTN:

4. ECG: check for left ventricular hypertrophy or ischaemic heart disease
5. Urine dipstick Albumin Creatinine ration (ABR): check for renal disease either as a cause or consequence of HTN
6. Fundoscopy: check for hypertensive retinopathy
7. Estimate 10 year risk of developing CVD using Q-risk

Question 17

What is QRisk2?

Answer 17

QRISK2 = assessment tool of 10 year risk of developing CVD

=> Age (25-84)
=> Sex
=> Ethnicity
=> Postcode

Clinical info:
=> Smoking status
=> Diabetes
=> Angina or heart attack in a 1st degree relative
=> CKD stage 4 or 5
=> AF
=> BP treatment 
=> Rheumatoid arthritis
=> Cholesterol / HDL ratio
=> Systolic BP
=> BMI - weight and height

Question 18

What lifestyle advice can be given to patients with HTN?

Answer 18

1. A low salt diet - aiming for less than 6g/day, ideally 3g/day.
   The average adult in the UK consumes around 8-12g/day of salt.
2. Caffeine intake should be reduced
3. Stop smoking
4. Drink less alcohol (14units spread across 3 days)
5. Eat a balanced diet rich in fruit and vegetables
6. Exercise more
7. Lose weight

Question 19

When do you treat Stage 1 (ABPM/HBPM >135/85mmHg) and Stage 2 (>=150/95mmHg) HTN?

Answer 19

Stage 1 HTN:
Treat if < 80 years of age AND any of the following:

• target organ damage
• established cardiovascular disease
• renal disease
• diabetes
• 10-year cardiovascular risk equivalent to 10% or greater

Stage 2 HTN:
Treat everyone regardless of age

Question 20

HTN treatment step 1:

Patients < 55-years-old or T2DM: ACE inhibitor OR a Angiotensin receptor blocker (ACE-i or ARB): (A)

(angiotensin receptor blockers should be used where ACE inhibitors are not tolerated (e.g. due to a cough)

Patients >= 55-years-old or of black African or African–Caribbean origin: Calcium channel blocker (C)

(ACE inhibitors have reduced efficacy in patients of black African or African–Caribbean origin are therefore not used first-line)

Answer 20

HTN treatment step 2:

If already on ACE-i or ARB, add a Calcium channel blocker or a thiazide-like Diuretic

If already taking a Calcium channel blocker, add an ACE-i or ARB or a thiazide-like Diuretic

=> Black African or African–Caribbean origin on a calcium channel blocker, consider ARB as a second agent

Question 21

HTN treatment step 3:

Add a third drug i.e.
If already taking an ACE-i / ARB + CCB, then add a Diuretic

If already ACE-i/ARB + Diuretics then add a CCB

Answer 21

HTN treatment Step 4:

NICE define step 4 as resistant hypertension and suggest either adding a 4th drug (as below) or seeking specialist advice
first, check for:

Confirm elevated clinic BP with ABPM or HBPM

Assess for postural hypotension.

Discuss adherence

=> If potassium < 4.5 mmol/l add low-dose spironolactone
=> If potassium > 4.5 mmol/l add an alpha- or beta-blocker

*Fail to respond to step 4 measures => referred to a specialist

Question 22

How do you manage Malignant hypertension?

Answer 22

If the blood pressure is >= 180/120 mmHg:

Admit for specialist assessment if:

=> signs of retinal haemorrhage or papilloedema (accelerated hypertension)
OR
=> life-threatening symptoms such as new-onset confusion, chest pain, signs of heart failure, or acute kidney injury

NICE recommend referral if a phaeochromocytoma is suspected (labile or postural hypotension, headache, palpitations, pallor and diaphoresis)

If none of the above then arrange urgent investigations for end-organ damage (e.g. bloods, urine ACR, ECG)

If target organ damage is identified, consider starting antihypertensive drug treatment immediately, without waiting for the results of ABPM or HBPM.

If no target organ damage is identified, repeat clinic blood pressure measurement within 7 days.

Question 23

Angiotensin-converting enzyme (ACE) inhibitors

1. MOA
2. Indication
3. Common side effects
4. Monitoring

Answer 23

1. Inhibit the conversion angiotensin I to angiotensin II
2. First-line treatment in younger patients (< 55 years old)

=> In all patients with diabetes, any age/ethnicity

=> Less effective in Afro-Caribbean patients

=> Must be avoided in pregnant women

=> Renal function must be check 2-3 weeks after starting due to the risk of worsening renal function in patients with renovascular disease

3. Cough, Angioedema, Hyperkalaemia
4. Monitoring:
   => measure renal function & serum electrolytes (K+) before starting treatment

=> Check renal function & serum electrolytes 1-2 weeks after starting treatment and 1-2 weeks after each dose increase

=> Check renal function & serum electrolytes annually

=> Check BP 4 weeks after each dose titration

Question 24

Calcium channel blockers

1. MOA
2. Indication
3. Common side effects
4. Monitoring

Answer 24

1. Block voltage-gated calcium channels relaxing vascular smooth muscle and force of myocardial contraction
2. First-line treatment in older patients (>= 55 years old) and in Afro-carribean patients
3. Flushing
   Ankle swelling
   Headache
4. Monitoring
   => Measure BP 4 weeks after each dose titration

Question 25

Thiazide type diuretics

1. MOA
2. Common side effects

Answer 25

1. Inhibit sodium absorption at the beginning of the distal convoluted tubule

2. Hyponatraemia
Hypokalaemia
Dehydration
Postural hypotension
Dizziness & headache

3. Monitoring:
   => Plasma sodium and potassium levels before starting the treatment and 1 week after + regularly thereafter

=> Renal and liver function before treatment - contraindicated in severe renal and liver impairment

Question 26

Angiotensin II receptor blockers (A2RB)

1. MOA
2. Indication
3. Common side effects
4. Monitoring

Answer 26

1. Block effects of angiotensin II at the AT1 receptor
2. Hyperkalaemia
3. Angiotensin II receptor blockers are generally used in situations where patients have not tolerated an ACE inhibitor, usually due to the development of a cough
   Drug names end in ‘-sartan’

=> Second added drug for afro-carribean patients over ACE-i

4. Monitoring:
   => Measure renal function (serum creatinine and estimated glomerular filtration rate) & serum electrolytes before starting treatment.

=> Check renal function & serum electrolytes 1–2 weeks after starting treatment and 1–2 weeks after each dose increase.

=> Check renal function & serum electrolytes annually

=> Check blood pressure 4 weeks after each dose titration.

Question 27

Take all these medications once a day. Can be any time of the day, as long as you remember to take them. Recent study has shown there may be more benefit to you if you take it at night.
With diuretics, take in the morning.

Answer 27

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