lecture 10: hypertension

Question 1

what is hypertension?

Answer 1

the level of blood pressure above which investigation and treatment will do more good than harm

Question 2

how many people does hypertension affect?

Answer 2

1 billion people and it is the highest global cause of death

Question 3

what is pre hypertension?

Answer 3

just before people get hypertension

Question 4

how does blood pressure change with age?

Answer 4

• the mean Blood pressure increases with age
• pulse pressure rises with age
• therefore majority of 60 + care hypertensive
• almost all 80+ are hypertensive

Question 5

is there a threshold for the risk of a stroke?

Answer 5

• there is no threshold for risk of stroke
• for every 20mmHg increase in BP doubles risk of the stroke
• as there is no threshold it means that a large burden of the disease is on people with a high blood pressure

Question 6

what is primary hypertension?

what is secondary hypertension?

Answer 6

• primary = hypertension from an unidentifiable cause (95%)

- secondary = hypertension from a disease of which hypertension is a symptom
5%

Question 7

what are the two types of genetic causes of hypertension?

Answer 7

• monogenic

- complex polygenic

Question 8

what are the monogenic causes?

how common?

Answer 8

• liddles syndrome

- Apparent mineralocorticoid excess

Question 9

what are the complex polygenic causes?

how common?

Answer 9

basically multiple genes causing hypertension

Question 10

what are some environmental causers of hypertension?

Answer 10

• dietary salt - principle cause
• obesity
• alcohol
• pregnancy
• pre natal environment

Question 11

what things is hypertension associated with?

Answer 11

• increased TPR
• reduced arterial compliance
• normal CO and normal blood volume

Question 12

what is isolated systolic hypertension?

Answer 12

• it is due to stiffer large arteries

- stiffer arteries reflect the pulse wave and amplify it instead of cushioning it

Question 13

what are reasons for increased TPR?

Answer 13

• active narrowing of the arteries (vasoconstriction)
• structural narrowing of the arteries (growth and remodelling)
• loss of capillaries

Question 14

what are some causes of hypertension?

Answer 14

• the kidneys
  play a role in salt regulation and therefore BP regulation
• sympathetic nervous system
• some evidence

Question 15

what are some results of hypertension?

Answer 15

• Coronary heart disease
• stroke
• heart failure
• atrial fibrillation
• dementia
• retinopathy

Question 16

how does hypertension affect the heart?

Answer 16

• causes hypertrophy
  (increase the muscle size)
• remodelling (change of ventricular volumes)

Question 17

how does hypertension affect the large arteries?

Answer 17

• accelerates atherosclerosis and aneurysms

Question 18

how does hypertension affect the retina?

Answer 18

• affects the microcirculation of the retina
• thickening of the small arteries
• means the arteries narrow
• vasospasm (spasming that results in vasoconstriction)
• this means less passage of blood happens
• more plasma leak happens

Question 19

how does hypertension affect microvasculature?

Answer 19

• less capillary density

- elevated capillary pressure

Question 20

how does hypertension affect kidneys?

Answer 20

Increased albumin secretion in urine

Question 21

possible treatment for hypertension?

Answer 21

• lifestyle changes
• ACE inhibitors and angiotensin receptor blockers
• diuretics