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Hypertension

Dr Rajesh Varma

  • Hypertension is a risk factor for CVD (myocardial infarction, angina, heart failure), stroke/TIA, and chronic kidney disease (CKD).

  • A meta-analysis has shown benefit (reduced risk for death and CVD) for preventive antihypertensive treatment of people with a baseline SBP ≥ 140 mm Hg.

  • 90% considered Primary Hypertension (no identifiable cause)

  • 10% considered Secondary Hypertension

Drugs:
Angiotensin-converting enzyme inhibitor (ACEi): lisinopril, perindopril and ramipril
Angiotensin II receptor antagonist (blocker) (ARB): candesartan, losartan and valsartan
Thiazide (TZ): hydrochlorothiazide, bendroflumethiazide
Thiazide-like diuretic (TLD): indapamide
Calcium-channel blocker (CCB):amlodipine, felodipine and lacidipine
Alpha-Blocker: doxazosin

Headlines

  1. If age <80y, aim clinic BP to <140/90 mmHg or ABPM/HBPM <135/85 mmHg

  2. Use ABPM/HBPM for diagnosis and monitoring treatment

  3. Hypertension and age<40y: consider specialist evaluation of secondary causes

  4. Additional therapies (e.g. statins, anti-platelet) are often required due to co-morbidities

  5. If BP is not controlled using triple therapy (ACEi or ARB + CCB + TZ/TLD), this equates to treatment-resistant hypertension. Consider:
    referral
    (if K<4.5) low-dose spironolactone
    (if K>4.5) alpha-blocker (e.g. doxazosin) or beta-blocker

  6. Whilst waiting for confirmation of diagnosis of hypertension, carry out investigations for target organ damage AND QRISK-3 risk assessment

Assessment

1. Establish diagnosis of hypertension: offer ABPM or 7-day HBPM

Hypertension is diagnosed if clinic BP ≥ 140/90 mmHg AND 7-day Ambulatory BP monitoring ≥ 135/85 mmHg

Stage 1 Hypertension BP 140-159 / 90-99
Stage 2 Hypertension BP 160-179 / 100-119
Stage 3 Hypertension BP ≥ 180/120

2. Assess cardiovascular risk and target organ damage

Use Q Risk 3 to determine 10-year CVD risk

Target organ damage (Hypertension-mediated organ damage HMOD)

  1. Fundoscopy: arteriolar narrowing, arteriovenous nicking, micro aneurysms, retinal haemorrhages, hard exudates, cotton wool spots, papilloedema

  2. Heart: 12-lead ECG to check for left ventricular hypertrophy

  3. Nephropathy (test for haematuria using a reagent strip, urine albumin:creatinine ratio)

Baseline investigations

  • Weight, BMI, waist circumference
    Obesity (BMI>30, waist>102cm in men or >88cm in women)
    Healthy BMI (BMI 20-25, waist<94cm in men and <80cm women)

  • Hb, UEs, eGFR, LFTs, HbA1C, lipids, Calcium, TFTs

3. Hypertensive and age<40y refer for specialist evaluation of secondary causes

Aim of therapy

If Age <80y, aim for clinic BP <140/90 OR ABPM <135/85
If Age ≥ 80y, aim for clinic BP <150/90 OR ABPM <145/85

Discuss with the person their individual cardiovascular disease risk and their preferences for treatment, including no treatment, and explain the risks and benefits before starting antihypertensive drug treatment.

High-risk population: Hypertensive and any of the following:

  • Target organ damage

  • Chronic Kidney Disease

  • Established CVD (CAD, MI, angina, TIA, stroke, aortic aneurysm, PAD)

  • Diabetes

  • 10-year CVD QRISK 3 ≥ 10%

Red Flag (same-day specialist review)

Stage 3 hypertension (clinic BP ≥ 180/120) with:

  • retinal haemorrhage or papilloedema (accelerated hypertension / malignant hypertension)

  • life-threatening symptoms such as new onset confusion, chest pain, signs of heart failure, or acute kidney injury

  • suspected phaeochromocytoma: labile or postural hypotension, headache, palpitations, pallor, and diaphoresis

Red Flag (immediately start antihypertensive treatment)

Stage 3 hypertension (clinic BP ≥ 180/120) without symptoms or signs indicating same-day referral, with target organ damage

Drug Therapy

STEP 1

*ACEi/ARB [check UEs baseline & 2w-post initiation/dosing change]
Type 2 diabetes (any age, any ethnicity)
Age <55yr (but not black African or African–Caribbean family origin)

CCB
Hypertension without type 2 diabetes AND
Age >55yr OR Black African/African–Caribbean family origin (any age)

STEP 2

ACEi/ARB + (CCB or TLD)

CCB + (ACE/ARB or TLD)

STEP 3

ACEi/ARB + CCB + TLD

STEP 4 (Treatment-resistant hypertension)

  1. Refer to specialist

  2. If serum potassium ≤ 4.5mM and non-impaired eGFR: add low-dose spironolactone (25-50mg od); check UEs 2w after as spironolactone carries a risk of hyperkalaemia

  3. if serum potassium ≥ 4.5mM: add doxazosin OR beta-blocker such as bisoprolol

STEP 5 Seek expert advice if BP is uncontrolled on optimal tolerated doses of 4 drugs

Lifestyle intervention for ALL hypertensives

  • Salt restriction (<5g per day)

  • High consumption of vegetables and fruit

  • Weight reduction and maintaining ideal body weight

  • Regular physical activity (at least 30min moderate dynamic exercise 5-7d per week)

  • Smoking cessation

  • Moderation of alcohol consumption (<14 units/week)

Screening and monitor for complications

  1. Monitoring response to treatment

  2. Set target clinic BP

  3. Optimise co-morbidities
    Antiplatelet therapy, such as low-dose aspirin, is recommended for secondary prevention of CVD
    Statins are recommended for adults assessed to be at high cardiovascular risk (QRISK 3 ≥ 10%)

  4. Check renal function annually (if proteinuria then check urine albumin:creatinine ratio)

Extra notes:

  1. Indapamide or chlortalidone (thiazide-like diuretic) are preferred over thiazide diuretics (bendroflumethiazide or hydrochlorothiazide)

  2. For individuals with diabetes, the recommended target BP is 140/80 (or <130/80 if there is nephropathy, retinopathy, or cerebrovascular damage).

  3. ACEi is associated with a small increased risk of angioneurotic oedema, especially in people of black African or Caribbean ethnicity.
    Therefore, in such groups use     ARB (if diabetic) or CCB (if not diabetic)

  4. Preference for beta-blocker in hypertensive adults with heart failure, angina, post-MI, heart rate control (AF), or younger women planning pregnancy

  5. Preference for ACEi/ARB in adults with heart failure, post-MI, CKD (diabetic and non-diabetic) and diabetes (reno-protective)

  6. Hypertension and diabetes: new research suggests SGLT2 inhibitors exhibit anti-diabetic, anti-hypertensive, cardioprotective and renoprotective effects

  7. Hypertensive and CKD:
    TLD is less effective antihypertensive in adults with moderate (eGFR<45) or severe (eGFR<30) renal impairment.
    In such circumstances, loop diuretics such as furosemide should replace TLD.

  8. Worsening eGFR following commencement of ACEi or ARB
    A rise in serum creatinine >30% may indicate underlying renovascular disease and HOSPITAL REFERRAL is advised.
    Caution: there is a risk of hyperkalaemia if adding spironolactone to hypertensive CKD whose eGFR<45 or where baseline serum potassium> 4.5mM

  9. Hypertensive and Heart Failure-Reduced Ejection fraction (HF-REF):
    Initial therapy ACEi/ARB + Beta-blocker + TZ/TLD (loop diuretic favoured if oedematous)
    Second-line: ACEi/ARB + Beta-blocker + TZ/TLD + MRA (spironolactone/eplerenone)
    Third-line: neprilysin inhibitor with ACEi (Sacubitril / Valsartan; Entresto) + Beta-blocker + TZ/TLD + MRA (spironolactone/eplerenone)

  10. Hypertensive and Atrial Fibrillation:
    Add oral anticoagulation when indicated according to the CHA2DS2-VASc score ≥1 in men and ≥2 in women, unless contraindicated
    Initial therapy ACEi/ARB + Beta-blocker/non-DHP CCB OR Beta-blocker + CCB
    Second-line: ACEi/ARB + Beta-blocker + DHP CCB/Diuretic OR Beta-blocker + DHP CCB + Diuretic
    Contraindicated to combine Beta-blocker with non-dihydropyridine CCB (e.g. verapamil or diltiazem) due to potential for profound bradycardia

  11. Hypertension treatment in older adults:
    Treat hypertension if aged≥ 80yr and aim for clinic BP<150/90 mmHg.
    Consider biological age (frailty, comorbidities, risk of falling, tolerability of BP-lowering medications) as well as chronological age and patient preference
    If frail, age≥80y, consider monotherapy