15 Hypertension

Question 1

What is the world prevalence for hypertension

Answer 1

1 billion

Question 2

Define hypertension

Answer 2

It can be defined as the level of BP that investigations and treatment does more good than harm. This is because the cutoff for hypertension is arbitrary. Although on UK guideline is it generally > 140/90 mmHg.

There is promotion about ambulatory BP and home BP monitoring - where the threshold is decreased by 5-10 mmHg

Question 3

What are the risk factors for hypertension

Answer 3

Monogenic and polygenic associations
Diet (salt)
Obesity
Alcohol
Pregnancy
Prenatal environment

Question 4

What are the causes of secondary hypertension. Name 2 monogenic diseases that can cause hypertension

Answer 4

Tumours secreting aldosterone (Conn’s syndrome),
Tumours secreting catecholamines,
Renal disease such as renal artery stenosis

Monogenic diseases:
Liddle’s syndrome: amiloride sensitive tubular Na+ channel causing excess reabsorption of sodium
Excess glucocorticoid hormone: 11b-HSD mutation

Question 5

What is the haemodynamic changes in patients with hypertension

Answer 5

• Increase TPR
• Normal CO
• Reduced arterial compliance
• Normal blood and ECF volume
• Shift in central blood volume (secondary to reduced venous compliance)

Question 6

What are the physiological changes that induce increased TPR

Answer 6

• Active narrowing of arteries (vasoconstriction)
• Structural narrowing of arteries (remodelling eg arterial wall hypertrophy)
• Loss of capillary (rarefaction)

Question 7

What are the candidates for the cause of primary hypertension

Answer 7

Kidneys
Sympathetic system
Endocrine/paracrine

Question 8

What are the complications associated with hypertension

Answer 8

MI
Stroke
Atheromatous disease
HF
Retinopathy
Dementia
Atrial fibrillation