Hypertension - Pathophysiology, Presentation & Investigation Flashcards
What is the worlds number 1 cause of preventable morbidity and mortality?
Hypertension
What does a 2mmHg rise in blood pressure lead to?
7% increased risk of mortality from ischemic heart disease
10% increased risk of mortability from stroke
How does the treatment of hypertension rank compared to other illness in terms of cost effectiveness?
Most cost effective treatment ever
What is morbidity?
The condition of being diseased
What is the condition of being diseased called?
Morbidity
What is mortality?
The state of being subject to death
What is the state of being subject to death called?
Mortality
What is a potential complication of hypertension, in terms of other organs?
End organ damage
What end organ damage can hypertension cause?
Stroke (brain)
Retinopathy (eyes)
Peripheral vasciular disease (blood vessels)
Renal failure (kidneys)
Coronary heart disease (heart)
What percentage of all strokes are due to blood pressure greater than 140mmHg?
40%
What does blood pressure fluctuate during the day due to?
Mental stress
Physical stress
What is hypertension?
Blood pressure above which the benefits of treatment outweight the risks in terms of morbidity and mortality
What in increasing blood pressure associated with?
Increased risk in stroke and cardiovascular disease
How does risk of stroke or cardiovascular disease change with rise in blood pressure?
Rises exponentially
How does hypertension change with age?
Blood pressure increases so hypertension is more likely
When is a patient considered to be hypertensive?
140/90mmHg
What are the stages of hypertension?
Stage 1
Stage 2
Severe
What is stage 1 hypertension?
Clinic blood pressure of 140/90mmHg
Ambulatory blood pressure monitoring (ABPM) daytime average of 135/85mmHg
What does ABPM stand for?
Ambulatory blood pressure monitoring
What is stage 2 hypertension?
Clinic blood pressure of 160/100mmHg
Ambulatory blood pressure monitoring daytime average of 150/95mmHg
What is severe hypertension?
Clinic systolic blood pressure of 180mmHg or diastolic blood pressure of 110mmHg
What is close to somebodies actual blood pressure?
Average blood pressure during the waking period
Why are clinical blood pressures not trustworthy?
Blood pressure increases due to being there
What percentage of blood pressure is primary?
90%
What percentage of blood pressure is secondary?
10%
What are some examples of causes of secondary hypertension?
Chronic renal disease
Renal artery stenosis
Endocrine disease
Cushings
Conn’s syndrome
Phaechromocytoma
When should someone with hypertension be seen by a professional?
Anyone under 40 as younger people are more likely to have an underlying cause which can be treated to prevent hypertension
What cause of death worldwide is hypertension?
Number 1 cause of death
What percentage of deaths is hypertension directly or indirectly responsible for?
>20%
How does the risk of hypertension change with other risk factors?
Increases exponentially
What are examples of risk factors for hypertension?
Cigarette smoking (adds 20/10mmHg)
Diabetes mellitus (5-30x increase of myocardial infarction)
Renal disease
Male (2x risk)
Hyperlipidaemia
Previous myocardial infarction or stroke
Left ventricular hypertrophy (2x risk)
How more at risk of hypertension are males than females?
2x
How much pressure does smoking add to your blood pressure?
20/10mmHg
What are primary contributors to hypertension?
Cardiac output (heart rate and stroke volume)
Total peripheral resistance
How does the sympathetic system control blood pressure?
Activation causes vasoconstriction, reflex tachycardia and increased cardiac output
Increases blood pressure
Why do the actions of the sympathetic system account for short term control of blood pressure?
They are rapid
What is an example of a system that controls blood pressure long term?
Renin-angiotensin-aldosterone system
What is the renin-angiotensin-aldosterone system responsible for?
Maintenance of sodium balance
Control of blood volume
Control of blood pressure
What is the renin-angiotensin-aldosterone system stimulated by?
Fall in blood pressure
Fall in circulating volume
Sodium depletion
What is the process of the renin-angiotensis-aldosterone system?
1) Renin is released from the juxtaglomerular apparatus
2) Renin converts angiotensinogen into angiotensin I
3) Angiontensin I is converted to angiotensin II by angiotensin converting enzyme (ACE)
4) Angiotensin II is a potent vasoconstrictor, anti-natruiretic peptide and stimulator of aldosterone release from adrenal glands
5) Aldosertone is also a potent antinatriuretic and antidiuretic peptide
Where is renin released from?
Juxtaglomerular appartatus
What does ACE stand for?
Angiotensin converting enzyme
Where is aldosterone released from?
Adrenal glands
What are negative effects of angiotensin II?
Potent hypertrophic agent which stimulates myocyte and smooth muscle hypertrophy in arterioles
What are key targets for the treatment of hypertension?
Sympathetic and renin-angiotensin-aldosterone systems
What does RAAS stand up for?
Renin-angiotensin-aldosterone system
What is the aetiology of hypertension?
Polygenic
Polyfactorial
What does polygenic mean?
From several genes acting together
What are the 2 different classes of genes that can cause hypertension?
Major genes (pronounced phenotype expression)
Poly genes (individual effect on phenotype is too small to be observed but can act together to produce an observable variation)
What are some examples of different causes of hypertension?
Major genes
Polygenes
Environment
What are examples of major genes that cause hypertension?
GRA
Angiotensinogen
Diabetes
What are examples of polygenes that cause hypertension?
Obesity
Race
Blood pressure
What are examples of environment causing hypertension?
Diet
Oral contraceptives
Physical activity
Stress
What are some likely causes of hypertension?
Increased reactivity of resistance vessels and resultant increase in peripheral resistance
Sodium homeostatic effect
Age
Genetics and family history
Environment
Diet
Alcohol intake
Weight
Race
What leads to increased reactivity of resistance vessels?
Hereditary defect of the smooth muscle lining arterioles
How does a sodium homeostatic effect cause hypertension?
Kidneys being unable to excrete appropriate amounts of sodium for any given blood pressure leads to sodium and fluid being retained and the blood pressure increasing
How does blood pressure change with age?
Increasing with age
Why does blood pressure increase with age?
Due to decreased arteriolar compliance
Why should hypertension in the elderly be treated as aggresively as in the young?
They have more to lose
Why must treatment for hypertension in the elderly be pragmatic?
Elderly people cannot withstand physiological changes like young people
Is there a link between genetics and hypertension?
Hypertension tends to run in families
What is the closest correlation of hypertension within families?
Between siblings not parent and child
How many genes have been recognised to be linked to hypertension?
More than 30, but each one only adds 0.5mmHg each
What are examples of how the environment affects blood pressure?
Mental and physical stress increases blood pressure
How does removing the environmental stress that causes blood pressure change the blood pressure?
It does not necessary decrease blood pressure
How can you tell if someone is a true stress responder (high blood pressure due to stress/environment)?
Very high blood pressure in the clinic but low or normal otherwise
Tend to be highly resistant to treatment
How does diet releate to hypertension?
Strong relationship between hypertension and salt intake
What can hypertensive patients do to their diet to reduce their blood pressure?
Reduce salt intake
What effect does people with normal blood pressure reducing salt intake have?
Little effect
What is one of the most common causes of hypertension in young Scottish people?
Alcohol intake
How do small amounts of alcohol impact blood pressure?
Decrease blood pressure
How does large amounts of alcohol intake impact blood pressure?
Increases blood pressure
What happens to blood pressure if alcohol intake is reduced?
It falls over several days to weeks
What is the average fall of someone who reduces alcohol intake?
5/3mmHg
What is the blood pressure like in obese patients?
Higher than skinnier patients
What percentage of hypertension is due in part or wholly to obesity?
Up to 30%
What will happen to a patients blood pressure if they lose weight?
It will fall
What can weight loss of 9kg change blood pressure by in patients with no other treatment?
19/18mmHg
What can weight loss of 9kg change blood pressure in patients with other treatment?
30/21mmHg
What is the most important non-pharmacological measure for managing blood pressure?
Weight loss
What is the relationship between birth weight and hypertension?
Birth weight is associated with the development of hypertension in later life, lower birth weight has a higher risk
How does the blood pressure of caucasians and black people compare?
Black people have a higher blood pressure
How does the blood pressure of black people living in rural Africa compare with ones living in towns?
Lower blood pressure in rural areas
What percentage of hypertension is secondary?
5-10%
Does removal of the cause of secondary hypertension treat the hypertension?
Not always
What are some examples of causes of secondary hypertension?
Renal disease
Drug induced
Pregnancy
Endocrine
Vascular
Sleep apnoea
What are examples of renal disease that can lead to hypertension?
Chronic pyelonephritis
Fibromuscular dysplasia
Renal artery stenosis
Polycystic kidneys
What is chronic pyelonephritis?
Continuing pyogenic infection of the kidney
What is continuing pyogenic infection of the kidney called?
Chronic pyelonephritis
What is fibromuscular dysplasia?
Abnormal growth within the wall of an artery that is not due to atherosclerotic or inflammatory disease
What is abnormal growth within the wall of an artery that is not due to atherosclerotic or inflammatory disease called?
Fibromuscular dysplasia
What is renal artery stenosis?
Narrowing of one of the renal arteries
What is narrowing of one of the renal arteries called?
Renal artery stenosis
What is polycystic kidneys?
Inherited disorder which is cyst formation and enlargement of the kidneys
What is an inherited disorder that causes cyst formation and enlargement of the kidneys called?
Polycystic kindeys
What are examples of drugs that can cause secondary hypertension?
NSAIDs
Oral contraceptives
Corticosteroids
What is pre-eclampsia?
Onset of high blood pressure during pregnancy
What is onset of high blood pressure during pregnancy called?
Pre-eclampsia
What are examples of endocrine problems that can lead to secondary hypertension?
Conn’s syndrome
Cushings disease
Phaechromocytoma
Hypo and hyperthyroidism
Acromegaly
What is conn’s syndrome?
Excessive production of the hormone aldosterone resulting in low renin levels
What is excessive production of the hormone aldosterone resulting in low renin levels called?
Conn’s syndrome
What is cushing’s disease?
Primary adrenal gland disease
What is phaeochromocytoma?
Neuroendocrine tumour of the medulla of the adrenal glands
What is a neuroendocrine tumour of the medulla of the adrenal glands called?
Phaeochromocytoma
What is hypo and hyperthyroidism?
Abnormally low or excessive thyroid production
What is abnormally low or excessive thyroid production called?
Hypo or hyperthyroidism
What is acromegaly?
Abnormal growth of the hands, feet and face caused by overproduction of growth hormone by the pituitary gland
What is abnormal growth of the hands, feet and face caused by overproduction of growth hormone by the pituitary gland called?
Acromegaly
What is an example of a vascular condition that can lead to secondary hypertension?
Coarctation of the aorta
What is coarctation of the aorta?
Aorta is narrow
What is it called when the aorta is narrow?
Coarctation of the aorta
What is sleep apnoea?
Pauses in breathing during sleep
What are pauses in breathing during sleep called?
Sleep apnoea