The Aetiology and Pathophysiology of Hypertension Flashcards
how does an increase in blood pressure of 2mmHg increase your risk of mortality from ischaemic heart disease?
by 7%
how does an increase in blood pressure of 2mmHg increase your risk of mortality from a stroke?
10%
what are the complications of hypertension in the brain?
haemorrhage, stroke, cognitive decline, Alzheimer’s,
what are the complications of hypertension in the eyes?
retinopathy
what are the complications of hypertension in the peripheries?
peripheral vascular disease: peripheral blood vessels block, narrow or spasm.
what are the complications of hypertension on the kidneys?
renal failuredialysistransplantationproteinuria
what are the complications of hypertension on the heart?
coronary heart diseasemyocardial infarctionleft ventricular hypertrophycongestive heart failure
what is congestive heart failure?
Inability of the heart to keep up with the demands on it, with failure of the heart to pump blood with normal efficiency.
what are the general types of stress which can cause hypertension?
mental and physical
how does the risk of cardiovascular disease and strokes change with increasing blood pressure?
it is an exponential increase
what also plays a part in the risk of cardiovascular disease and stroke with hypertension?
age
what is the general consensus for the bp at which a patient is hypertensive?
140/90
what is the optimum bp that must be aimed for in hypertensives?
<120/<80
what is ABPM and what is its advantage over clinical blood pressure?
ambulatory blood pressure monitoring. it provides a more accurate measure of blood pressure as blood pressure measured in the clinic tends to be higher than normal
what is clinical bp for type 1 hypertension?
140/90 mmHg or higher
what is the ABPM for type 1 hypertension?
daytime average of 135/85 mmHg or higher
what is the clinical bp for type 2 hypertension?
160/100 mmHg or higher
what is the ABPM in type 2 hypertension?
daytime averge of 150/95 or higher
what is the clinical bp for severe hypertension?
180/110 or higher
what is primary hypertension?
hypertension with no underlying cause
what is secondary hypertension?
hypertension with an underlying cause
what are some causes of secondary hypertension?
chronic renal diseaserenal artery stenosisendocrine disease (cushngs, Conn’s syndrome, phaechromocytoma, GRA [Glucocorticoid remediable aldosteronism]
what other factors apart from increases in blood pressure can cause an increase in morbidity from hypertension?
-Cigarette smoking -Diabetes mellitus -Renal disease-Male -Hyperlipidaemia -Previous MI or stroke -Left ventricular hypertrophy
a hypertensive patient who smokes will have a morbidity risk the same as a hypertensive with of a bp of what?
20/10 mmHg greater than the smoker’s
how does having diabetes mellitus affect the risk of MI in a hypertensive?
5-30 times increase
what is the increased risk of morbidity due to hypertension of a male compared to a female?
2 times
patients with left ventricular hypertrophy will have an increased risk of…?
2 times that hypertensive of same bp without the condition
what is the risk of morbidity of a hypertensive patient who smokes and has diabetes
much higher than the two risks combined as diabetes and smoking work synergistically to increase risk of morbidity from hypertension
what are the two prime contributors to blood pressure?
cardiac output (stroke volume and heart rate)total peripheral resistance
what are the mechanisms that the sympathetic system increases blood pressure?
vasoconstrictionincreased cardiac outputreflex tachycardia
what are the three functions of the renin-angiotensin aldosterone system?
maintenance of sodium balancecontrol of blood pressurecontrol of blood volume
how does angiotensin II increase blood pressure?
it is a vasoconstrictorit is an anti-natriuretic peptideit stimulates aldosterone release from the adrenal glandsit is a potent hypertrophic agent which stimulates myocytes and smooth muscle hypertrophy in the arterioles
what does aldosterone do to increase blood pressure?
it causes sodium and water to be rebsorbed
if hypertensive patients have hypertrophy of smooth muscle and myocytes what happens to their prognosis?
it is poorer
what are the two most likely causes of hypertension?
-increased reactivity of the resistance vessels -a sodium homeostatic effect
what causes an increase reactivity of the resistance vessels in hypertensives?
a result of hereditary defect of the smooth muscle lining arterioles (this causes an increased TPR),
what causes hypertension in patients with a sodium homeostatic problem?
the kidneys are unable to excrete appropriate amounts of sodium for any given BP as a result sodium and fluid are retained and BP increases
what are some other factors that can cause hypertension?
agegenetics and family historyenvironmentweightalcohol intakeracesalt intake
how does BP change with increasing age? and why is this though to happen?
it increases, though to be because arteries become more inelastic and compliance decreases
how should hypertension in the elderly be treated, compared to younger people?
just as aggressively, however blood pressure may be kept a little higher to prevent syncope
between which family member’s does the closest correlation between hypertension exist?
siblings
what environmental factors increase the risk of hypertension?
mental and physical stress
can hypertension presist after stress is removed?
yes
does decreasing salt intake help to reduce BP?
yes
what quantities of alcohol increase blood pressure?
large quantities
what is the average fall in bp after reducing alcohol intake?
5/3 mmHg, very small
does weight loss cause decrease in BP in hypertensives?
yes, it can produce large decrease and so is the most important non-pharmacological treatment of the condition(9kg loss can cause fall of 19/18 in non-medicated and 30/21 in medicated)
how does birth weight affect the likelihood of developing hypertension in later life?
the lower the birthweight the higher the likelihood of hypertension in later life
which races are most susceptible to hypertension?
black populations, reasons are unclear
what renal diseases can cause secondary hypertension?
chronic pyelonephritisfibromuscular dysplasiarenal artery stenosispolycystic kidneys
what is chronic pyelonephritis?
inflammation and fibrosis of the kidneys associated with repeated infections
what is fibromuscular dysplasia?
abnormal growth within the arteries which is non arthrosclerotic and non-inflammatory
what are the drug induced causes of secondary hypertension?
NSAIDSoral contraceptivecorticosteroids
what condition in pregnant women causes hypertension?
pre-eclampsia
which endocrine disorders can cause hypertension?
Conn’s syndromeCushing’s diseasepheochromocytomahypo and hyperthyroidismacromegaly
what is pheochromocytoma?
a tumour of the adrenal tissue that causes overproduction of adrenaline and noradrenaline
what is acromegaly?
pituitary gland produced too much growth hormone in adulthood
what vascular disease can causes hsecondary hypertension?
coarctation of the aorta
what sleep condition can cause secondary hypertension?
sleep apnoea
