Treatment of hypertension Flashcards
Why do we need to identify true hypertension ?
Because the normal day to day variation in BP we need 20-30 clinic readings to be certain of true BP
Must use ABPM or HBPM
What are the risk factors we need to assess ?
Previous stroke, MI, IHD Smoking Diabetes mellitus Hypercholesterolaemia Family history Physical examination
What investigations are used for end organ damage ?
ECHO/ECG- LVH
Urine analysis- proteinuria
renal ultrasound
renal function
What treatable causes would we screen for ?
Obesity Renal artery stenosis/ FMD Conn's, Cushing's, Pheochromocytoma Coarctation Drug induced Sleep apnoea
What risk assessment tools can be used to quantify risk ?
Assign risk calculator/ Q-risk
What are the reasons for treating hypertension ?
Reduce cerebrovascular disease
Reduce MI by 16-30%
How do we treat hypertesnion ?
Stepped approach
Use low doses of several; drugs
This approach minimises adverse events and maximises pateint compliance
What is the treatment of hypertension un <55yrs ?
ACEI/ ARB
Beta-blocker
What is the treatment of hypertension in >55yrs or afro-Caribbean ?
Calcium channel blocker
Thiazide- type diuretic
What is the treatment of stage 1 hypertension ?
Offer antihypertensive drug treatment to people ages under 80 years with ABPM >135/85 with one or more of the following:
- target organ damage - established cardiovascular disease - renal disease - diabetes - a 10yr cardiovascular risk equivalent to 10% or greater
What is the treatment for stage 2 hypertension ?
Offer antihypertensive drug treatment to people of any age with stage 2 hypertension
What is the treatment for people <40yrs with stage 1 hypertension ?
Seek specialist evaluation of secondary causes of hypertension
More detailed assessment of potential target organ damage
What is the treatment of the elderly pateint ?
Offer people aged 80ys or above the same antihypertensive drug treatment as people ages 55-80 years, taking into account any co-morbidities
BP target is different in the pateints >80yrs
<145/85
How should we choose the right antihypertensive drug ?
Step 1 treatment in those people ages over 55yrs and black people of any age:
- start treatment with: - calcium channel blocker - thiazide like diuretic
What is step 1 treatment ?
Patient under 55 years offer ACE/ARB
Not:
- African or Caribbean- less effective and higher risk of angioedema
- women of child bearing age- teratogenic
What is step 2 treatment ?
Add thiazide-type diuretic such as indapamide to CCB or ACEI/ARB
What is step 3 treatment ?
Add CCB, ACEI, diuretic toghether
What is the treatment of resistant hypertension ?
Step 4 treatment
What is step 4 treatment ?
Consider compliance issues
Consider higher-dose thiazide-like diuretic treatment if the blood potassium level is higher than 4.5mmol/l
Consider further diuretic therapy with low-dose spironolactone 25mg once daily) if blood
potassium level is <4.5mmol/l
If there are no contraindications should we start treatment for resistant hypertension ?
Yes, start treatment according to age and other pathology
If over 55 years:
- a CCB or thiazide-like diuretic
Dont use max dose as side effects more common
For resistant hypertension, what should we use if pateint is young and male ?
An ACEI or ARB
If single agent doesn’t control BP, then add a second agent
What does ACE inhibitors do ?
Completely inhibit the actions of angiotensin converting enzymes- ACE
ACE converts angiotensin I to active angiotensin II which is a potent vasoconstrictor
What are examples of ACEI ?
Ramipril
Perindopril
What are the contraindications of ACEI ?
Renal artery stenosis: - may precipitate renal failure of renal infacrtion Impaired renal function: - renal failure Hyperkalaemia: - worsens it Fertile female: - teratogenic
What are the drug-drug interactions of ACEI ?
NSAIDs:
- precipitate acute renal failure
Potassium supplements:
- hyperkalaemia
Potassium sparing diuretics:
- hyperkalaemiaWhat is the most common side effect of ACEI ?
Cough
What do angiotensin II receptor blockers do ?
Angiotensin II antagonists competitively block the actions of angiotensin II at the angiotensin AT1 receptor
What are examples of ARBs ?
Losartan
Valsartan
Candesartan
Irbesartan
What are the vasodilating calcium channel blockers and what do they do ?
Amlodipine/felodipine
Reduce peripheral resistance
What are the rate limiting CCBs and what do they do ?
Verapamil/diltiazem
Block the L-type calcium channel in the myocytes of the vasculature and heart
Vasodilating CCBs are the choice when ?
Over 55yrs
Women of child bearing age (nifedipine modified release), compliance is high
Benefit in the elderly pateint with systolic hypertension
Rarely cause postural hypotension
What are the adverse drug effect of CCBS ?
Flushing
Headache
Ankle oedema
Indigestion and reflux oesophagitis
What are the contraindications to CCBs ?
Acute MI
Heart failure, bradycardia (rate limiting)
What can rate limiting agents cause ?
Bradycardia
Constipation
What is the common first line treatment for mild-moderate hypertension in people of African origin ?
Thiazide-type diuretics
What are examples of Thiazide type diuretics ?
Indapamide
Clortalidone
What are the mechanisms of action of thiazide type diuretics ?
Urinary excretion of sodium
Resistance vessel dilatation
What are the adverse drug effects of thiazide type diuretics ?
Gout
ED
What are commonly less used agents ?
Alpha-adrenoceptor antagonists:
- Doxazosin
Centrally acting agents:
- Methyldopa
- Moxonidine
Vasodilators:
- Hydralazine
- MinoxidilWhat are examples of Alpha-adrenoreceptor blocker ?
Doxazosin
Methyldopa
Moxonidine
What is the mechanism of action of Doxazosin ?
Selectively block post synaptic alpha1- adrenoreceptors
Oppose vascular smooth muscle contraction in arteries
What are the adverse drug reactions of doxazosin ?
First dose hypertension
Dizziness
Dry mouth
Headache
When is methyldopa used ?
Hypertension in pregnancy
What are the adverse drug effects of Methyldopa ?
Sedation and drowsiness
Dry mouth and nasal congestion
Orthostatic hypotension
What is the action of Moxonidine ?
Centrally acting imidazoline agonist
Ideal pateint population in which it should be used has not be defined
What are the common treatment regimes for pateints >55yrs ?
Start CCB- no or incomplete effect Add thiazide-like diuretic- incomplete effect Add ACEI - still incomplete effect Add B-blocker- still incomplete effect Add one of the less commonly used agents
What is the treatment regime for young pateints ?
Start ACEI
If female of child bearing age start CCB or B-blocker
No or incomplete effect
Add thiazide type diuretic- incomplete effect
Add CCB- still incomplete effect
Add B-blocker- still incomplete effect
Add one of the less commonly used agents
