Hypertension
Summary
Hypertension is sustained elevation of blood pressure, defined as clinic BP 140/90 mmHg or higher (or ABPM/HBPM 135/85 mmHg or higher). It is a major modifiable cardiovascular risk factor and the leading risk factor for mortality globally. Most cases are primary (essential) hypertension with no identifiable cause. Secondary causes should be considered in young patients, resistant hypertension, or those with suggestive features. NICE recommends confirming diagnosis with ambulatory BP monitoring (ABPM). Treatment follows a stepwise approach: ACEi/ARB, then calcium channel blocker, then thiazide-like diuretic. Target BP is less than 140/90 (or less than 130/80 if high CV risk, diabetes, or CKD).
Key Facts
- Definition: Clinic BP 140/90+ OR ABPM/HBPM 135/85+
- Prevalence: 30% of adults; increases with age
- Demographics: More common in older adults, African-Caribbean descent
- Classification: Primary (90-95%) vs Secondary (5-10%)
- Gold Standard Diagnosis: ABPM (or HBPM if ABPM declined/not tolerated)
- First-line Treatment: ACEi/ARB OR CCB (based on age/ethnicity)
- Prognosis: Treatment reduces MI, stroke, HF, CKD progression
Clinical Pearls
ABPM Pearl: NICE requires ABPM to confirm hypertension and stage it. Clinic BP alone is not sufficient for diagnosis.
A+C+D Pearl: NICE stepwise: Step 1: A (ACEi/ARB) or C (CCB); Step 2: A+C; Step 3: A+C+D (thiazide-like); Step 4: Add spironolactone if K+ permits.
African-Caribbean Pearl: CCB is first-line for Black African/Caribbean patients of any age (reduced RAA system response).
White Coat Pearl: White coat hypertension (high clinic, normal ABPM) increases CV risk slightly. Monitor annually.
Secondary Pearl: Consider secondary causes in: age less than 40, resistant HTN, hypokalaemia, renal bruits, cushingoid features.
Why This Matters Clinically
Hypertension is the most important modifiable CV risk factor. Treatment prevents stroke, MI, HF, and CKD progression. Most patients are asymptomatic - screening and opportunistic BP measurement are essential.
Prevalence
| Age Group | Prevalence |
|---|---|
| 18-39 | 10% |
| 40-59 | 35% |
| 60+ | 60%+ |
| Overall adults | 30% |
Demographics
- Increases with age
- Higher in African-Caribbean populations
- More common in men until 45; equalises after menopause
Risk Factors
| Category | Factors |
|---|---|
| Non-modifiable | Age, family history, ethnicity, male sex |
| Modifiable | Obesity, high sodium diet, low potassium, sedentary lifestyle, excess alcohol, smoking |
| Comorbidities | Diabetes, CKD, OSA |
Primary (Essential) Hypertension (90-95%)
Multifactorial:
- Genetic predisposition
- Sympathetic nervous system overactivity
- Renin-angiotensin-aldosterone system (RAAS) activation
- Endothelial dysfunction
- Arterial stiffness
- Sodium retention
Secondary Hypertension (5-10%)
| Cause | Features |
|---|---|
| Renal parenchymal disease | CKD, raised creatinine |
| Renovascular disease | Renal artery stenosis, abdominal bruit |
| Primary aldosteronism | Hypokalaemia without diuretics |
| Phaeochromocytoma | Episodic HTN, sweating, palpitations |
| Cushing's syndrome | Cushingoid features, hypokalaemia |
| Coarctation of aorta | Arm-leg BP difference, young patient |
| OSA | Snoring, daytime somnolence |
| Drug-induced | NSAIDs, steroids, OCP, cocaine |
Usually Asymptomatic
Symptoms of Severe/Complicated HTN
Secondary HTN Clues
| Finding | Suggests |
|---|---|
| Young age (less than 40) | Secondary cause |
| Resistant HTN | Secondary, non-adherence, white coat |
| Hypokalaemia | Primary aldosteronism |
| Abdominal bruit | Renovascular disease |
| Radio-femoral delay | Coarctation |
| Cushingoid | Cushing's syndrome |
| Episodic symptoms | Phaeochromocytoma |
Red Flags - Hypertensive Emergency
[!CAUTION] BP greater than 180/120 with:
- Papilloedema (malignant HTN)
- Acute coronary syndrome
- Heart failure
- Aortic dissection
- Stroke/encephalopathy
- Acute kidney injury
- Eclampsia
Blood Pressure Measurement
- Correct cuff size (bladder 80% of arm circumference)
- Seated, arm supported at heart level
- After 5 minutes rest
- Measure both arms (use higher reading)
- Record as average of last 2 readings
Examination for End-Organ Damage
| System | Findings |
|---|---|
| Cardiovascular | Apex displacement (LVH), S4, murmurs |
| Fundoscopy | Arteriolar narrowing, AV nipping, haemorrhages, exudates, papilloedema |
| Renal | Bruits (renovascular disease) |
| Neurological | Focal signs (stroke) |
Features of Secondary Causes
- Cushingoid features
- Thyroid signs
- Radio-femoral delay
Confirming Diagnosis
| Method | Threshold |
|---|---|
| Clinic BP | 140/90 mmHg or higher |
| ABPM (preferred) | Daytime mean 135/85 or higher |
| HBPM | Mean 135/85 or higher |
Staging (NICE)
| Stage | Clinic BP | ABPM/HBPM |
|---|---|---|
| Stage 1 | 140-159/90-99 | 135-149/85-94 |
| Stage 2 | 160-179/100-109 | 150-174/95-109 |
| Stage 3 (severe) | 180+/110+ | 175+/110+ |
Baseline Investigations (All Patients)
| Test | Purpose |
|---|---|
| U&E | Renal function, hypokalaemia |
| Glucose/HbA1c | Diabetes screening |
| Lipid profile | CV risk |
| Urinalysis | Proteinuria, haematuria |
| 12-lead ECG | LVH, ischaemia |
Additional (if secondary cause suspected)
- Renal ultrasound, renal artery Doppler
- Aldosterone:renin ratio
- 24-hour urinary catecholamines/metanephrines
- Dexamethasone suppression test
- MRI adrenals
QRISK3
- 10-year CV risk calculation
- Used to guide statin therapy
Management Algorithm (NICE)
CONFIRMED HYPERTENSION (ABPM/HBPM)
↓
┌────────────────────────────────────────────────────────────┐
│ LIFESTYLE MODIFICATION (ALL) │
│ - Salt restriction (less than 6g/day) │
│ - Weight loss if overweight │
│ - Regular exercise │
│ - Limit alcohol │
│ - Stop smoking │
│ - DASH diet │
└────────────────────────────────────────────────────────────┘
↓
┌────────────────────────────────────────────────────────────┐
│ STEP 1 │
│ Age less than 55 or diabetes: A (ACEi or ARB) │
│ Age 55+ or Black African/Caribbean: C (CCB - amlodipine) │
└────────────────────────────────────────────────────────────┘
↓
┌────────────────────────────────────────────────────────────┐
│ STEP 2 │
│ A + C │
└────────────────────────────────────────────────────────────┘
↓
┌────────────────────────────────────────────────────────────┐
│ STEP 3 │
│ A + C + D (Thiazide-like) │
│ (Indapamide 1.5mg or chlortalidone 12.5-25mg) │
└────────────────────────────────────────────────────────────┘
↓
┌────────────────────────────────────────────────────────────┐
│ STEP 4 (Resistant HTN) │
│ Check K+: │
│ - If K+ 4.5 or less → Add spironolactone 25mg │
│ - If K+ greater than 4.5 → Alpha-blocker or beta-blocker │
│ Specialist referral if still uncontrolled │
└────────────────────────────────────────────────────────────┘
Drug Classes
| Class | Examples | Notes |
|---|---|---|
| ACEi | Ramipril, lisinopril | First-line if less than 55, DM, CKD. Cough SE |
| ARB | Losartan, candesartan | If ACEi intolerant |
| CCB | Amlodipine | First-line if 55+ or Black. Ankle oedema SE |
| Thiazide-like | Indapamide, chlortalidone | Step 3. Check U&E |
| MRA | Spironolactone | Step 4. Monitor K+ |
| Alpha-blocker | Doxazosin | Step 4 alternative |
| Beta-blocker | Bisoprolol | Less preferred; use if compelling indication |
Treatment Targets
| Population | Clinic BP Target | ABPM/HBPM Target |
|---|---|---|
| Under 80 years | Less than 140/90 | Less than 135/85 |
| 80 years and over | Less than 150/90 | Less than 145/85 |
| Diabetes/CKD/high CV risk | Less than 130/80 | Less than 125/75 |
Hypertensive Emergency
- Controlled BP reduction (not precipitous - risk of stroke)
- IV labetalol, sodium nitroprusside, or GTN infusion
- Specialist/HDU management
| Complication | Mechanism |
|---|---|
| Stroke | Ischaemic and haemorrhagic |
| Coronary artery disease | Accelerated atherosclerosis |
| Heart failure | LVH → diastolic then systolic dysfunction |
| Chronic kidney disease | Nephrosclerosis |
| Peripheral arterial disease | Atherosclerosis |
| Retinopathy | Microvascular damage |
| Aortic dissection | Intimal tear |
Benefits of Treatment
- 40% reduction in stroke
- 20-25% reduction in MI
- 50% reduction in heart failure
BP Control Rates
- Less than 50% of treated patients achieve target BP
- Adherence is a major challenge
Key Guidelines
-
NICE Guideline NG136. Hypertension in adults — 2019 (updated 2022)
-
ESC/ESH Guidelines for Management of Arterial Hypertension — 2018
-
AHA/ACC Guideline for High Blood Pressure — 2017
Landmark Trials
SPRINT
- Intensive BP control (target less than 120) reduced CV events
- PMID: 26551272
ALLHAT
- Thiazides as effective as CCBs and ACEi for outcomes
- PMID: 12479763
PATHWAY-2
- Spironolactone most effective add-on for resistant HTN
- PMID: 26559744
What is high blood pressure?
High blood pressure means the force of blood pushing against your artery walls is too high. Over time, this can damage your heart, brain, kidneys, and eyes.
Why does it matter?
High blood pressure usually has no symptoms, but if untreated, it significantly increases your risk of heart attack, stroke, and kidney disease.
Treatment
- Lifestyle changes: reduce salt, lose weight, exercise, limit alcohol
- Medication: usually one or more tablets taken daily
- The goal is to get your BP below 140/90 (or lower if you have diabetes or kidney disease)
Taking your medication
- Take tablets at the same time each day
- Don't stop without discussing with your doctor
- Some medications may cause side effects - discuss alternatives if needed
-
NICE Guideline NG136. Hypertension in adults: diagnosis and management. 2019.
-
Williams B et al. 2018 ESC/ESH Guidelines for the management of arterial hypertension. Eur Heart J. 2018;39(33):3021-3104. PMID: 30165516
-
SPRINT Research Group. A Randomized Trial of Intensive versus Standard Blood-Pressure Control. N Engl J Med. 2015;373(22):2103-2116. PMID: 26551272
-
Williams B et al. Spironolactone versus placebo, bisoprolol, and doxazosin to determine optimal treatment for resistant hypertension (PATHWAY-2). Lancet. 2015;386(10008):2059-2068. PMID: 26414968
-
ALLHAT Officers. Major outcomes in high-risk hypertensive patients randomized to ACE inhibitor or calcium channel blocker vs diuretic. JAMA. 2002;288(23):2981-2997. PMID: 12479763
-
Whelton PK et al. 2017 ACC/AHA Guideline for High Blood Pressure. Hypertension. 2018;71(6):e13-e115. PMID: 29133356
Viva Points
"Hypertension is diagnosed with ABPM (135/85+). NICE stepwise: A or C first (A if under 55/DM; C if 55+/Black), then A+C, then A+C+D, then spironolactone. Target less than 140/90. Secondary causes: renovascular, primary aldosteronism, phaeo, Cushing's. Treatment reduces stroke 40%, MI 25%."
Common Mistakes
- ❌ Diagnosing without ABPM
- ❌ Wrong drug for age/ethnicity
- ❌ Not checking for secondary causes in young/resistant HTN
- ❌ ACEi + ARB together (avoid combination)
- ❌ Not monitoring U&E with ACEi/ARB/diuretics
Last Reviewed: 2026-01-01 | MedVellum Editorial Team