HYPERTENSION Flashcards
What os hypertension?
Persistently raised arterial bp
Whats the current threshold for suspecting hypertension?
clinic systolic blood pressure sustained above or equal to 140 mmHg, or diastolic blood pressure sustained above or equal to 90 mmHg, or both.
Whats the difference between primary and secondary hypertension?
Primary has no identifiable cause - most common, occurs in 90%
Secondary has a known underlying cause e.g. renal disease or use of drugs
Outline the staging for hypertension?
Stage 1 hypertension — clinic blood pressure ranging from 140/90 mmHg to 159/99 mmHg and subsequent ABPM daytime average or HBPM average blood pressure ranging from 135/85 mmHg to 149/94 mmHg.
Stage 2 hypertension — clinic blood pressure of 160/100 mmHg or higher but less than 180/120 mmHg and subsequent ABPM daytime average or HBPM average blood pressure of 150/95 mmHg or higher. (The upper limit of Stage 2 hypertension is variably defined in other guidelines internationally.)
Stage 3 or severe hypertension — clinic systolic blood pressure of 180 mmHg or higher or clinic diastolic blood pressure of 120 mmHg or higher.
What is accelerated hypertension?
Aka malignant hypertension
a severe increase in blood pressure to 180/120 mmHg or higher (and often over 220/120 mmHg) with signs of retinal haemorrhage and/or papilloedema. It is usually associated with new or progressive target organ damage.
What is white coat hypertension?
blood pressure that is unusually raised when measured during consultations with clinicians but is normal when measured in ‘non-threatening’ situations.
It is reported to occur in about 15–30% of the population.
A ‘white-coat’ effect is defined by NICE as a discrepancy of more than 20/10 mmHg between clinic and average daytime ABPM or average HBPM blood pressure measurements at the time of diagnosis, but is generally used to describe persistent discrepancy between clinic and home or ambulatory day time averages in those being treated for hypertension and those who are not.
What is masked hypertension?
where clinic blood pressure measurements are normal (less than 140/90 mmHg) but blood pressure measurements are higher when taken outside the clinic using average daytime ABPM or average HBPM blood pressure measurements.
Outline the epidemiology of hypertension?
In 2017 11.8 million adults in England had it - 1 in 4 adults
Prevalence is slightly higher in men
Prevalence increases with advancing age, rising to over 60% in people aged over 60 years.
What are risk factors for hypertension?
Age
Gender 0 men
Ethnicity
Genetic factors
Social deprivation
Co-existing diabetes or renal disease
Lifestyle factors
Anxiety and emotional stress
Which ethnicities are more likely to be diagnosed with hypertension?
people of black African and black Caribbean origin
Outline the genetic factors of hypertension?
research on twins suggest that up to 40% of variability in blood pressure may be explained by genetic factors. A positive family history increases the risk of developing hypertension.
Outline how social deprivation affects hypertension?
people from the most deprived areas in England are 30% more likely to have hypertension than those from the least deprived.
What lifestyle factors affect your risk of hypertension?
smoking, excessive alcohol consumption, excess dietary salt, unhealthy diet, obesity, and lack of physical activity are associated with hypertension.
Why can anxiety or emotional stress increase your blood pressure?
Due to increased adrenaline and cortisol levels
What are some secondary causes of hypertension?
Renal disorders - most common!
Vascular disorders - renal artery stenosis and coarctation of aorta
Endocrine disorders - primary hyperaldosteronism
Phaeochromocytoma, Cushing, acromegaly, hypothyroidism, hyperthyroidism
Drugs and alcohol
Pregnancy
Others - connective tissue disorders, retroperitoneal fibrosis, obstructive sleep apnoea
why can obstructive sleep apnoea cause hypertension?
Repetitive OSA-induced hypoxemia and hypercapnia elicit reflex changes in both sympathetic and parasympathetic activation. These autonomic derangements, with consequent increases in catecholamine levels, persist even into the daytime and could contribute to the development of HTN
What drugs can cause secondary hypertension?
Alcohol
Ciclosporin
Substance of abuse e.g. cocaine
Combined oral contraceptive
Corticosteroids
EPO
Leflunomide
Liquorice
NSAIDs
Stimulants to treat ADHD e.g. methylphenidate
Sympathomimetics e.g. ephedrine and phenylpropanolamine (may be found in OTC cough and cold remedies)
Venlafaxine
What renal disorders can cause secondary hypertension?
CKD
Chronic pyelonephritis
Diabetic nephropathy
Glomerulonephritis
Polycystic kidney disease
Obstructive uropathy
Rena cell carcinoma
Outline how coarctation of the aorta can affect hypertension?
usually results in upper-limb hypertension. There can be a significant difference in blood pressure between the left and right arms. Other signs include absent or weak femoral pulses, radio-femoral delay, palpable collateral blood vessels in the back muscles, and a suprasternal murmur radiating through to the back.
When should you suspect renal artery stenosis causing secondary hypertension?
suspect this if the person has peripheral vascular disease and an abdominal bruit, or if blood pressure is resistant to treatment, if plasma renin level is increased
How does primary hyperaldosteronism present?
People usually present with hypokalaemia, alkalosis (elevated bicarbonate level), and plasma sodium level greater than 140 mmol/L, or a larger than expected decrease in serum potassium when using a low-dose thiazide-type diuretic. The symptoms may be non-specific, but rarely it may present with tetany, muscle weakness, nocturia, or polyuria.
How does a phaeochromocytoma present?
people can present with intermittently high or labile blood pressure, or postural hypotension, headaches, sweating attacks, palpitations, or unexplained fever and abdominal pains. Alternatively, it can be asymptomatic
Why is Phaeochromocytoma important to exclude as a cause of hypertension?
because malignant transformation or catastrophic haemorrhage from these tumours can be fatal.
What conditions does hypertension increase the risk of?
HF
CAD
Stroke
CKD
PAD
Vascular dementia
What proportion of all heart attacks and stroke are associated with hypertension?
Over half
Explain how correction of hypertension reduces health risks?
A study found…
Every 10 mmHg reduction in blood pressure resulted in
A 17% reduction in coronary heart disease.
A 27% reduction in stroke.
A 28% reduction in heart failure.
A significant 13% reduction in all-cause mortality.
How should you measure the bp in a pt with symptms of postural hypotension?
measure blood pressure with the person either supine or seated.
Measure blood pressure again with the person standing for at least 1 minute before measurement.
If the systolic blood pressure falls by 20 mmHg or more when the person is standing, measure subsequent blood pressures with the person standing.
What should you do if the bp measured in the clinic is 140/90 mmHg or higher?
take a second measurement during the consultation.
If the second measurement is substantially different from the first, take a third measurement.
Record the lower of the last two measurements as the clinic blood pressure.
If the person’s blood pressure is between 140/90 mmHg and 180/120 mmHg, offer ambulatory blood pressure monitoring (ABPM) to confirm the diagnosis of hypertension. If ABPM is unsuitable or the person is unable to tolerate it, offer home blood pressure monitoring (HBPM).
How should you advise a pt on using ambulatory blood pressure monitoring? How should you as the doctor use this information?
ensure that at least two measurements per hour are taken during the person’s usual waking hours (for example between 8 am and 10 pm).
Use the average value of at least 14 measurements taken during the person’s usual waking hours to confirm a diagnosis of hypertension.
How should you advise a pt on using home blood pressure monitoring? How should you as the doctor use this information?
For each blood pressure recording, two consecutive measurements are taken, at least 1 minute apart and with the person seated.
Blood pressure is recorded twice daily, ideally in the morning and evening.
Blood pressure recording continues for at least 4 days, ideally for 7 days — discard the measurements taken on the first day and use the average value of all the remaining measurements to confirm the diagnosis of hypertension.
ambulatory vs home blood pressure monitoring?
The ambulatory blood pressure monitor checks your blood pressure at frequent intervals throughout one day and one night. It consists of a cuff which wraps around your arm. The cuff is attached to a small electric recording device on a belt or strap worn on your body.
Home bp monitoring measures your blood pressure twice a day, once in the morning and once in the evening. On each occasion you should take two readings, one minute apart. You should take readings for 4-7 days. You will do this manually with a blood pressure monitor the GP gives you and it should be done at rest
