Hypertension Flashcards
What are the treatment targets of HTN?
(for both general and special populations)
(taken from NUH Guide)
General:
* < 140/90 mmHg in patients aged < 80 years
* < 150/90 mmHg in patients aged ≥ 80 years (do not decrease diastolic BP to < 60 mmHg)
Special Populations:
* < 140/80 mmHg for patients with diabetes mellitus
≤ 130/80 mmHg in patients with proteinuria (with/without diabetes)
* < 150/100 mmHg in pregnant patients without target organ damage (do not decrease diastolic BP to < 80 mmHg)
* < 140/90 mmHg in pregnant patients with target organ damage
* < 220/120 mmHg during 1st 24hrs of acute stroke (lower with care by 10-15%) (lower by 10/5 mmHg if BP > 140/90 mmHg after acute phase of stroke)
List 5 risk factors for CVD
- Smoking
- High BP (Grade 1/2 HTN)
- Age (≥ 55 in men, ≥ 65 in women)
- Family History of premature HTN (≤ 55 in men, ≤ 65 in women)
- Dyslipidemia: Total Cholesterol > 6.2mmol/L (240 mg/dL), Triglycerides > 1.7 mmol/L (150 mg/dL), HDL < 1.0mmol/L (40 mg/dL), LDL > 4.1mmol/L (160 mg/dL)
- Diabetes Mellitus
- Obesity
What are some lifestyle modifications / non-pharmacological management of HTN?
- Restrict salt intake (5 - 6g daily)
- Increase consumption of vegetables, fruits, low-fat dietary products
- Decrease intake of saturated and total fats
- Reduce weight to BMI < 23 kg/m3 and waist circumference < 90 cm in men, < 80 cm in women
- Do at least 30 min of moderate dynamic exercise (5-7 days per week)
- Quit smoking
- Reduce alcohol intake (< 2 standard drinks/day for men, < 1 standard drink/day for women)
Note: recommend lifestyle changes to all hypertensive pts, and in pts with high normal BP. HOWEVER, drug tx should not be delayed without reason beyond 3-6 months if indicated.
When initiating tx, aim for BP control within ____ months
1 drug ≈____mmHg
3 months
10/5mmHg
Recommended follow-up intervals
(taken from NUH Guide)
6 months:
* Good BP control AND no complications
3-4 months:
* Good BP AND elderly/ has complications (e.g. IHD, CVA, renal impairment)
* Adherent to tx AND with or without complications/ comorbidities AND stable but sub-optimal control related to individual targets for BP, HbA1C, cholesterol over past 4-6 months
2 weeks:
* ACEi / ARB initiation or up-titration (test K and Cr)
* Poor BP control AND requires titraiton of meds
What first-line and add-on HTN drugs are preferrably indicated in pts with these comorbidities / compelling indications:
1. DM
2. Chronic kidney disease/ proteinuria
3. HF
4. Isolated systolic HTN (older persons)
5. MI or AF
6. Recurrent stroke prevention
7. Pregnancy
8. BPH
Looking at the 4 main HTN drug classes: ACEi / ARB, BB, CCB, Diuretics
Good to rationalise in your head the reasons for the use of these drugs!
- ACEi (preferred if proteinuric) / ARB, add-on CCB, diuretics
- ACEi / ARB
- ACEi / ARB, diuretics
- Diuretics, long-acitng CCB
- BB, add-on ACEi / ARB (LV dysfunction)
- Diuretic, ACEi
- Methyldopa, nifedipine, labetalol
- Prazosin
What HTN drugs are contraindicated in pts with these comorbidities:
1. Asthma / bronchospasm
2. HF or 2°/3° heart block
3. Gout
4. Bilateral renal artery stenosis
5. DM
5. Pregnancy / breastfeeding
Looking at the 4 main HTN drug classes: ACEi / ARB, BB, CCB, Diuretics
Good to rationalise in your head the reasons for the avoidance of these drugs!
- BB (prevents bronchodilation due to bronchial beta-2 receptors. Beta-1 selectivity is not absolute, and may diminish at higher doses, so there’s still that risk for selective BBs)
- BB, diltiazem/ verapamil
- Diuretic
- ACEi, ARB
- BB (mask signs of hypoglycemia e.g. tachycardia, palpitations, tremors)
- ACEi, ARB, diuretic
List 4 common antihypertensive combinations that should be avoided/ not used and why?
- BB + ACEi / ARB -> does not produce synergistic BP reduction
- ACEi + ARB -> decreases GFR in CKD pts
- BB + non-DHP CCB -> increased risk of bradycardia and/or atrioventricular block, since both classes have negative inotropic and chronotropic effects
- BB + Diuretic -> increases risk of developing DM
When should you substitute another HTN drug from a different class instead of increasing the dose of the first drug?
When no/ limited response or was poorly-tolerated
When should you add-on a second agent from a different class?
When inadequate response (fail to achieve target BP) but well tolerated
Add-on diuretic first if not already used
MoA of ACEi
Taken from ACE Guidelines Dec 2023, to update to that in formulary
Inhibits formation of angiotensin II
-> increases vasodilation
MoA of ARB
Taken from ACE Guidelines Dec 2023, to update to that in formulary
Blocks type 1 angiotension II receptors
-> prevents vascular contraction
Common and max doses of ACEis:
1. Lisinopril
2. Enalapril
3. Captopril
Taken from NUH Guide
Order is in ascending order of cost
- 5-40mg OD, max 40mg/day
- 5-20mg BD, max 40mg/day
- 12.5-25mg TDS, max 150mg/day
Strengths available
1. Lisinopril: 5, 10, 20mg tablets
2. Enalapril: 5, 10, 20mg tablets
3. Captopril: 12.5, 25mg tablets
Renal dose adjustments for ACEis:
1. Lisinopril
2. Enalapril
3. Captopril
Taken from ACE Guidelines Dec 2023 and UTD
Lisinopril
* CrCl 10-30: initial 2.5-5mg OD
* CrCl <10: initial 2.5mg OD
* HD: 2.5mg OD, administer post HD on dialysis days
* PD: 2.5mg OD
Enalapril
* CrCl 10-30: initial 2.5mg/day in 1-2 divided doses, max 20mg/day
* CrCl <10: initial 1.25mg OD or 2.5mg every other day, max 10mg/day
* HD: dialyzable, 2.5mg 3 times weekly post HD, max 10mg OD
* PD: dialyzable, dose as in CrCl <10
Captopril
* CrCl 10-50: 75% of normal dose Q12-18h, max 50mg Q12h
* CrCl <10: 50% of normal dose Q24h, max 50mg Q24h
* HD: administer usual dose Q24hr, administer after post HD on dialysis days, max 50mg Q24h
* PD: administer usual dose Q24h, max 50mg Q24h
Hepatic dose adj for ACEis
1. Lisinopril
2. Enalapril
3. Captopril
No dose adj needed
Common and max doses of ARBs:
1. Losartan
2. Telmisartan
3. Irbesartan
4. Candesartan
5. Valsartan
Taken from NUH Guide
Order is in ascending order of cost
- 25-100mg OD, max 100mg/day
- 40-80mg OD, max 80mg/day
- 150-300mg OD, max 300mg/day
- 8-16mg OD, max 32mg/day
- 40-160mg OD, max 320mg/day
Strengths available
1. Lorsartan: 50, 100mg tablets
2. Telmisartan: 40, 80mg tablets
3. Irbesartan: 150, 300mg tablets
4. Candesartan: 8mg tablets
5. Valsartan: 80, 160mg tablets
Renal dose adjustments for ARBs:
1. Losartan
2. Telmisartan
3. Irbesartan
4. Candesartan
5. Valsartan
Taken from ACE Guidelines Dec 2023 and UTD
- CrCl <20: initial 25mg OD, poorly dialyzed so no dose adj needed for HD and PD
- no dose adj needed, poor dialyzed so no dose adj needed for HD and PD
- no dose adj needed, poor dialyzed so no dose adj needed for HD and PD
- CrCl ≤30: initial 4mg OD, max 16mg/day, not significantly dialyzed but follow CrCl≤30 dose for HD and PD
- no dose adj needed, poor dialyzed so no dose adj needed for HD and PD
Hepatic dose adjustments for ARBs:
1. Losartan
2. Telmisartan
3. Irbesartan
4. Candesartan
5. Valsartan
Taken from UTD
- Mild to moderate hepatic impairment: initial 25mg OD
- Hepatic impairment: initial 40mg OD
- no dose adj needed
- Moderate to severe hepatic impairment (child-Pugh class B, C): initial 4-8mg OD
- no dose adj neeeded
ADRs of ACEi / ARB
- Severe hypotension
- Acute renal failure
- Hyperkalemia
- Angioedema and dry cough (less in ARB)
Use with caution / C/Is of ACEi / ARB
Pregnancy / breastfeeding, bilateral renal artery stenosis
for ACEi only: idiopathic / hereditary angioedema
Monitoring parameters of ACEi / ARBs (include what and when to monitor/ follow-up)
Moniter K and Cr Q2-4 weeks
* before initiation
* after initiation
* after dose up-tiration
Once stable, monitor at least once every 12 months
MoA of CCB
Taken from ACE Guidelines Dec 2023, to update to that in formulary
Prevents calcium from entering the cells of the heart and arteries
-> reduces contraciton of arteries
-> allows vasodilation
Common and max doses of CCBs:
1. Amlodipine
2. Nifedipine LA
3. Diltiazem tablets
4. Diltiazem SR capsules
Taken from NUH Guide
Order is in ascending order of cost
- 2.5-10mg OD, max 10mg/day
- 30-90mg OD, max 120mg/day
- 30-60mg TDS, max 360mg/day
- 90-200mg OD, max 360mg/day
Strengths available
1. Amlodipine: 5, 10mg tablets
2. Nifedipine LA: 30, 60mg tablets
3. Diltiazem tablets: 30, 60mg tablets
4. Diltiazem SR capsules: 90, 100, 200mg capsules
Renal dose adjustments for CCBs
1. Amlodipine
2. Nifedipine LA
3. Diltiazem
Taken from ACE Guidelines Dec 2023
No dose adj needeed
HD, PD: poorly dialyzed, no dose adj needed
Hepatic dose adjustments for CCBs
1. Amlodipine
2. Nifedipine LA
3. Diltiazem
Taken fron UTD
- initial 2.5mg OD
- No dose adj needed, CL is reduced in pts with cirrhosis so monitor closely for ADRs and consider dose adj
- No dose adj needed, Half life is increased in pts with cirrhosis so monitor closely for ADRs and consider dose adj
ADRs of CCBs
Taken from NUH Guide and UTD
Peripheral oedema, flushing
diltiazem: hepatotoxicity, bradycardia , cutaneous hypersensitivity reactions
Use with caution / C/Is of CCBs
Caution:
* pts with HF. If to use, amlodipine is the preferred choice
* DHP: hepatic impairment
* non-DHP: heart block, LV dysfunction, hepatic impairment
C/Is
* Diltiazem: sick sinus syndrome, 2°/3° heart block, acute MI, pulmonary congestion
For non-DHP, avoid abrupt discontinuation
MoA of diuretics
Taken from ACE Guidelines Dec 2023, to update to that in formulary
Reduces sodium reabsorption at different sites in the nephron
-> increases urinary sodium and water loss
Common and max doses of diuretics:
1. Hydrochlorothiazide
2. Indapamide tablets
3. Indapamide SR tablets
Taken from NUH Guide
Order is in ascending order of cost
- 12.5-25 OD, max 50mg/day
- 2.5-5mg OD, max 5mg/day
- 1.5mg OD, max 1.5mg/day
Strengths available
1. Hydrochlorothiazide: 25mg tablets
2. Indapamide: 2.5mg tablets, SR 1.5mg tablets
Renal dose adjustments for diuretics:
1. Hydrochlorothiazide
2. Indapamide
Taken from ACE Guidelines Dec 2023
Hydrochlorothiazide
* Use with caution in renal impairment
* CrCL <10: use not recommended due to lack of efficacy
* HD, PD: use not recommended due to lack of efficacy
Indapamide
* CrCL <30: contraindicated
* HD, PDL not significantly dialyzable, no dose adj needed
Hepatic dose adjustments for diuretics
1. Hydrochlorothiazide
2. Indapamide
No dose adj needed
ADRs of diuretics
- Hypokalaemia (more likely for doses ≥25mg OD)
- Hyponatremia
- Hypercalcemia
- Increased urination
- Increased uric acid production
- Hyperglycaemia
Use with caution / C/Is of diuretics
Caution: risk of sqaumous cell carcinoma, DM, gout
C/I
* Hydrochlorothiazide: pregnancy, renal decompensation, anuria
* Indapamide: sulphonamides allergy, severe renal disease (ineffective)
Monitoring parameters of diuretics (include what and when to monitor/ follow-up)
Monitor K and Na levels Q2-4 weeks
* before initiation
* after initiation
* after dose up-titration
Once stable, monitor at least once every 12 months
MoA of BBs
Taken from ACE Guidelines Dec 2023, to update to that in formulary
Blocks neurotransmitters in norepinephrine and epinephrine from binding to receptors
Common and max doses of BBs:
1. Atenolol
2. Bisoprolol
3. Carvedilol
4. Metoprolol
Taken from NUH Guide
Order is in ascending order of cost
- 25-100mg OD, max 100mg/day
- 1.25-10mg OD, max 20mg/day
- 3.125 OD - 25mg BD, max 50mg/day
- 25 BD - 50mg TDS, max 400mg/day
Strengths available
1. Atenolol: 50, 100mg tablets
2. Bisoprolol: 2.5, 5mg tablets
3. Carvedilol: 6.25, 25mg tablets
4. Metoprolol: 50, 100mg tablets
Renal dose adjustments for BBs:
1. Atenolol
2. Bisoprolol
3. Carvedilol
4. Metoprolol
Taken from ACE Guidelines Dec 2023 and UTD
Atenolol
* CrCl <50: reduce daily dose by 50% (12.5-50mg OD, max 50mg/day)
* CrCl<25, reduce daily dose by 75% (6.25-25mg OD, max 25mg/day)
* HD: moderately dialyzed, initial 25-50mg OD, administer post HD on dialysis days
* PD: not significantly dialyzed, max 25mg/day
Bisoprolol
* CrCl <20: 1.25-2.5mg OD, max 10mg/day
* HD: moderately dialyzed, initial 1.25-2.5mg OD, max 10mg/day, administer post HD on dialysis days
* PDL slightly dialyzable, initial 1.25-2.5mg OD, max 10mg/day
Carvedilol and metoprolol: no dose adj needed. No dose adj needed for HD and PD
Hepatic dose adjustments for BBs
1. Atenolol
2. Bisoprolol
3. Carvedilol
4. Metoprolol
Taken from UTD
- no dose adj needed
- hepatitis, cirrhosis: initial 2.5mg OD
- Severe impairment: use is contraindicated
- No specific dose adj, but consider intiating with reduced doses and gradual dosage titration due to extensive hepatic metabolism
ADRs of BBs
- Hypotension
- Masking of hypoglycemia
- Bronchospasm (esp non-selective)
- AV node block, bradycardia
Use with caution / C/Is of BBs
Taken from NUH Guide
C/Is
* Asthma
* Sinus node dysfunction
* Pregnancy
* DM
* Uncompensated HF
* Heart block greater than 1°
Avoid uprubt discontinuation
What are the differences between cardioselective and non-selective BBs? In what conditions are one preferred over the other?
Taken from ACE Guidelines Dec 2023
Cardioselective:
* e.g. Atenolol, bisoprolol, metoprolol, nebivolol
* APrimarily targets only beta-1 receptors in the heart
* Have more favourable SE profile
* Less likely to cause constriciton of airways
* Preferred for pts with respiratory diseases, and for management of CHD, chronic HF, acute coronary syndrome, and some arrhthymias
Non-selective
* e.g. Propranolol, carvedilol
* Targets both beta-1 and beta-2 receptors throughout the body, hence can cause more SEs beyond the heart
* Preferred for pts who require tx for migraine prveention, essential tremor, or portal HTN in cirrhosis
Note that beta-1 selectivity is not absolute, however, and may diminish at higher doses
Common and max dose of spironolactone (mineralocorticoid receptor antagonist, MRA)
Taken from NUH Guide
25mg OD, max 50mg/day
Strength available
Spironolactone 25mg tablets
Renal dose adjustments for spironolactone (mineralocorticoid receptor antagonist, MRA)
Taken from UTD
**For HF only **
* eGFR >50 mL/minute/1.73 m2: No initial dosage adjustment necessary
* eGFR 30 to 50 mL/minute/1.73 m2: Initial: 12.5 mg once daily or every other day; may double the dose every 4 weeks if serum potassium remains <5 mEq/L and kidney function is stable, up to a maximum target dose of 25 mg/day
* eGFR <30 mL/minute/1.73 m2: Use not recommended; heart failure clinical trials excluded patients with serum creatinine ≥2.5 mg/dL
For HD and PD, not routinely recommended, though unlikely to be significantly dialyzed given high degree of protein binding. Initial 12.5mg OD or every other day
From NUH Guide: should usually be restricted to pts with eGFR≥ 45ml/min and plasma K concentration of ≤4.5mmol/L
Hepatic dose adjustments for spironolactone
Taken from UTD
No dose adj needed
ADRs of spironolactone
Taken form NUH Guide
- Gynecomastia/ breast tendernss
- Impotence in man
- Menstrual irregularities in women
- Hyperkalemia, esp when taken tgt with ACEi/ARBs
Use with caution / C/Is of spironolactone
Taken from UTD
Caution: fluid/ electrolyte imbalance
C/Is: severe kidney impairment (eGFR<30ml/min), anuria, pregnancy, breastfeeding
Monitoring parameters of spironolactone
Taken from NUH Guide and UTD
Monitor electrolytes (K) and eGFR soon after initiation (1w, then again 2-4w later), and at least annually thereafter
Common and max dose of hydralazine (vasodilator)
Taken from NUH Guide
10-50mg TDS, max 300mg/day
**Strengths available **
Hydralazine 10, 25, 50mg tablets
Renal dose adjustments for hydralazine (vasodilator)
Taken from UTD
GFR<10ml/min, HD, PD: administer usual dose every 8-12hrs
Hepatic dose adjustments for hydralazine
Taken from UTD
No dose adj provided
However, note that hydralazine undergoes extensive hepatic metabolism
ADRs of hydralazine
Taken from NUG Guide and UTD
Lupus-like syndrome (more likely with larger dose, longer duration)
Tachycardia, flushing, peripheral oedema
Use with caution / C/Is of hydralazine
Taken fron NUH Guide and UTD
C/I: Mitral valve rheumatic heart disease, coronary artery disease, idiopathic systemic lupus erythematosus and related diseases, severe tachycardia
Common and max dose of prazosin (alpha blocker)
Taken from NUH Guide
0.5-1mg TDS, max 20mg/day
Strength available
Prazosin 1mg tablet
Renal dose adjustment of prazosin (alpha blocker)
Taken from UTD
- eGFR <60 mL/minute/1.73 m2: low doses, titrate cautiously
- HD, PD: unlikely to be dialyzed (highly protein bound), no adj needed
Hepatic dose adjustments for prozasin
Taken from UTD
No dose adj provided
ADRs of prazosin
Taken from NUH Guide and UTD
Orthostatic hypotension, floppy iris syndrome
Fatigue, edema, priapism, CNS depression
Use of caution / C/Is of prazosin
Taken from UTD
Cateract surgery pts, HF
From BEERs Criteria, avoid use of prazosin in HTN because:
- Non-selective peripheral alpha-1
blocker - High risk of orthostatic hypotension and
associated harms, especially in older adults; not recommended as routine treatment for
hypertension - Alternative agents have superior
risk/benefit profile.
Common and max dose of methyldopa (centrally acting agent)
Taken from NUH Guide
125-500mg TDS, max 3000mg/day
Strength available
Methyldopa 250mg tablets
Renal dose adjustment of methyldopa (centrally acting agent)
Taken from UTD
- CrCl >50 mL/minute: Administer Q8h
- CrCl 10 to 50 mL/minute: Administer Q8-12h
- CrCl <10 mL/minute: Administer Q12-24h
- HD: Moderately dialyzable, administer after hemodialysis on dialysis days
- PD: Administer Q12-24h
Hepatic dose adjustments for methyldopa
Taken from UTD
No dose adj provided.
C/I in active/acute hepatic diseasee
ADRs of methyldopa
Taken from UTD
Edema, hepatotoxicity + more
sry i sianz to do, someone help fill
Use with caution / C/Is of methyldopa
Taken from NUH Guide and UTD
C/Is: acute liver disease, current MAOi therapy
Resistant hypertension is defined as:
BP that remains above goal despite concurrent use of three antihypertensive agents of different classes at optimal/ best tolerated doses, one of which should be a diuretic
What are the possible causes of resistant hypertension?
- Non-adherence ot medication
- “White coat” effect
- Wrong cuff size
- Lifestyle factors (obesity/ large weight gain, excessive alcohol consumption, high alcohol intake)
- Chronic intake of vasopressor / sodium-retaining drugs (sympathomimetics, nasal decongestants, oral contraceptives, NSAIDs)
- Obstructive sleep apnoea
- Chronic pain
- Secondary hypertension
- Advanced end-organ damage (e.g. renal impairment)
Pharmacological and non-pharmacological measures for resistant hypertension
Pharmacological:
* Add-on low dose spironolactone
* If intolerant to spironolactone, add-on further diuretic therapy like higher dose thiazide/ thiazide-like diuretic, or loop diuretic for pts with renal impairment (GFR ≤30ml/min)
* Or add-on bisoprolol
Non-pharmacological:
* Check and reinforce adherence to medication / diet / lifestyle measures (esp reduction of sodium intake)
* Address any drug interactions and associated medical problems, if present
