Hypertension

Question 1

How is hypertension defined?

Why is it difficult to define in absolute terms?

Answer 1

a state of chronically and abnormally high arterial blood pressure

• it has a skewed normal distribution so is difficult to define in absolute terms
• this means that HTN should be diagnosed with a range of readings and looking at the overall trend, rather than an isolated reading

Question 2

Why is it important to identify patients with raised blood pressure?

Answer 2

• it is one of the most important and treatable causes of premature morbidity and mortality
• it is a major risk factor for cardiovascular disease
• it also is a risk factor for stroke, MI, heart failure, chronic kidney disease and cognitive decline

Question 3

What is the prevalence of HTN?

Answer 3

1 in 3 adults in the UK

• it affects around 31% of men and 26% of women

Question 4

Why can diagnosing HTN be difficult?

What are the consequences of this?

Answer 4

• HTN can often be asymptomatic
• in this case, diagnosis depends on clinician awareness and opportunistic measurements of BP
• 50% of people with HTN remain undiagnosed and are not receiving treatment

Question 5

What are the risk factors associated with HTN?

Answer 5

• age
• sex
  
  • women have a lower BP than men up to 65, then between 65-74 women have a higher BP
• ethnicity
  
  • Black African and Black Caribbean at higher risk
• genetic factors
• social deprivation
• lifesytle
  
  • smoking, excessive alcohol, excessive salt, obesity & lack of physical activity
• anxiety / emotional stress
  
  • raises adrenaline and cortisol levels

Question 6

What is ideal blood pressure and what blood pressure measurement is classed as hypertension?

What type of hypertension are patients assumed to have?

Answer 6

normal BP is < 120/80mmHg

• ranges of 120-140 mmHg for systolic and 80-90mmHg are considered high normal
• HTN is diagnosed with persistent systolic BP > 140mmHg and diastolic BP > 90mmHg or BOTH
• assumed to have essential (primary) HTN as secondary HTN is very rare
  
  • this is HTN in the absence of any pathological cause

Question 7

When might “white-coat” HTN be suspected?

Answer 7

• if there is a discrepancy of more than 20/10mmHg between clinic and average daytime ABPM / HBPM measurements

Question 8

When might masked HTN be suspected?

Answer 8

• when clinic blood pressure measurements are normal (<140/90mmHg)
• but average HBPM / ABPM measurements outside the clinic are higher

Question 9

What is meant by stage 1 HTN?

Answer 9

• clinic BP ranging from 140/90mmHg to 159/99mmHg
• AND subsequent ABPM daytime average of 135/85mmHg to 149/94mmHg

Question 10

What is meant by stage 2 HTN?

Answer 10

• clinic BP of 160/100 mmHg or higher, but less than 180/120 mmHg
• AND subsequent ABPM daytime average of 150/95 mmHg or higher

Question 11

What is meant by stage 3 HTN?

Answer 11

• clinic systolic BP of 180 mmHg or higher
• OR clinic diastolic BP of 120 mmHg or higher

Question 12

After coming to the conclusion that the patient does NOT have HTN, what would you do depending if there is evidence of target organ damage?

Answer 12

Evidence of target organ damage:

• consider investigations to look for other causes of the damage

No evidence of target organ damage:

• repeat clinic blood pressure readings every 5 years
• consider repeating more frequently if clinic BP is close to 140/90mmHg

Question 13

If someone is found to have high blood pressure in the clinic, what other investigations should be performed?

Answer 13

• a full cardiovascular examination - including peripheral pulses, auscultation for carotid bruits
• body mass index calculation
• fundoscopy
• dipstick urinalysis
• U&Es

Question 14

If someone is found to have BP > 140/90mmHg in clinic, what should be the next steps?

Answer 14

• if BP >140/90 mmHg then take a second measurement during the consultation
• if the second measurement is substantially different from the first, take a third BP measurement
• record the lower of the last 2 measurements as the clinic BP
• if BP > 140/90mmHg and <180/120mmHg, then offer ambulatory BP monitoring (ABPM) to confirm diagnosis
• if ABPM is unsuitable, home BP monitoring (HBPM) is offered instead

Question 15

What investigations would be performed to assess for target organ damage in a hypertensive patient?

Answer 15

this involves assessment of the heart, eyes and kidneys

Heart:

• 12-lead ECG to look for LV hypertrophy and signs of coronary heart disease

Eyes:

• fundoscopy to look for signs of hypertensive retinopathy

Kidneys:

• dipstick urinalysis to look for proteinuria and/or haematuria
  
  • these are both signs of glomerular damage
• U&Es, creatinine clearance and eGFR to assess renal function

Question 16

How would cardiovascular risk be assessed in someone with HTN?

Answer 16

this involves fasting blood glucose and lipid profile

• lipid profile measures the level of serum total cholesterol, HDL, LDL and triglycerides
• high concentration of fasting blood glucose indicates possible diabetes and increases the risk
• 10-year risk of developing CVD can be evaluated using QRISK tool

Question 18

What is the treatment for stage 1 HTN?

(clinic BP 140/90 - 159/99 and ABPM 135/85 - 149/94)

Answer 18

• assess cardiovascular risk and target organ damage
• offer lifestyle advice
• start drug therapy in cases of increased CVD risk, target organ damage or no improvement
• consider specialist referral if patient <40 or HTN is resistant to treatment

Question 19

What lifestyle advice may be offered to someone with stage 1 HTN?

Answer 19

• improve diet - especially reducing salt intake to <6g / day
• reduce alcohol intake to no more than 3-4 units (men) or 2-3 units (women) daily
• smoking cessation
• weight loss and improvement in physical activity
• discourage excessive consumption of coffee / caffeinated beverages

Question 20

What is the treatment for stage 2 HTN?

(BP > 160/100 and < 180/120 or > 159/95 ABPM)

Answer 20

• assess cardiovascular risk and target organ damage
• start drug therapy and advise on lifestyle interventions
• consider specialist referral if <40 or HTN is resistant to treatment

Question 21

What is different in the treatment of stage 3 HTN?

Answer 21

• drug therapy is started immediately without ABPM or HBPM and regardless of target organ damage and CVD risk

Question 22

How are BP targets different based on age?

Answer 22

• the aim of treatment is to gradually reduce and maintain BP at the target

Age < 80 years:

• clinic BP < 140/90mmHg
• ABPM < 135/85mmHg

Age > 80 years:

• clinic BP < 150/90mmHg
• ABPM < 145/85mmHg

Question 23

What is involved in the first step of pharmacological treatment for HTN?

Answer 23

• patients < 55 are started on an ACEi or ARB
• patients > 55 or who are black or of African or Carribbean heritage (any age) are started on a CCB
• patients with type 2 diabetes are started on a ACEi or ARB

Question 24

What is the involved in the second step of pharmacological treatment for HTN?

Answer 24

if patient is taking ACEi / ARB:

• add CCB or thiazide-like diuretic

if patient is taking CCB:

• add ACEi / ARB or a thiazide-like diuretic

Question 25

WHat is involved in the third step of the pharmacological management of HTN? What happens if this is unsuccessful?

Answer 25

* triple therapy involves ACEi / ARB + CCB + thiazide-like diuretic * if this is unsuccessful then confirm resistant HTN with elevated BP through ABPM or HBPM * consider specialist referral or add: * low dose spironolactone if K+ \< 4.5 mmol/l * alpha or beta-blocker if K+ \> 4.5 mmol/l * seek expert advice if BP not controlled on 4 drugs

Question 26

When should you refer someone with a clinic BP \> 180/120mmHg (stage 3 HTN)?

Answer 26

* evidence of **retinal haemorrhage or papilloedem**a, suspected **phaeochromocytoma** or life-threatening symptoms * if not, consider starting **_drug therapy immediately_** without ABPM / assessing target organ damage * **repeat clinic BP in 7 days** to see if medication has had an effect

Question 27

What is important to remember when prescribing an ACEi?

Answer 27

* repeat U&Es within 14 days of starting treatment * repeat after changing each titration dose

Question 28

What is meant by secondary HTN?

Answer 28

* in 5% of patients, a **specific cause** for their high BP can be identified * secondary HTN is more likely when: * early onset HTN \< 40 years * unexpectedly severe HTN * resistant HTN