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This is a clinician-written, evidence-based summary aligned to the 2026 MLA Content Map. It is intended for medical students and junior doctors preparing for the UKMLA. Always cross-reference with NICE guidance, local protocols, and clinical judgement.
The Bottom Line
- Diagnosis requires ABPM or HBPM confirmation (threshold ≥135/85 mmHg) — do not diagnose on clinic readings alone
- Stage 1: clinic ≥140/90, ABPM ≥135/85. Stage 2: clinic ≥160/100, ABPM ≥150/95. Stage 3: clinic ≥180/120
- Step 1: ACEi/ARB (if <55 or T2DM) OR CCB (if ≥55 or Afro-Caribbean). Step 2: combine. Step 3: add thiazide-like diuretic. Step 4: add spironolactone (K⁺ ≤4.5) or alpha/beta-blocker
- Target: <140/90 mmHg (clinic) for most; <150/90 if ≥80 years
- Assess 10-year CVD risk (QRISK3) and check for target organ damage at diagnosis
Overview
Hypertension is defined as persistently elevated arterial blood pressure. Primary (essential) hypertension accounts for 90–95% of cases and has no identifiable cause. Secondary hypertension (5–10%) has an underlying aetiology such as renal artery stenosis, phaeochromocytoma, Conn syndrome, Cushing syndrome, coarctation of the aorta, or drug-induced causes. NICE NG136 mandates out-of-office measurement (ABPM or HBPM) to confirm diagnosis and exclude white-coat hypertension. Classification uses clinic BP: Stage 1 (≥140/90), Stage 2 (≥160/100), and Stage 3 (≥180/120) which is a hypertensive emergency if signs of end-organ damage are present.
Epidemiology
Hypertension affects approximately 1 in 3 adults in the UK, with many undiagnosed. Prevalence increases with age, affecting over 50% of people over 60. It is the leading modifiable risk factor for stroke, heart failure, chronic kidney disease, and coronary heart disease. Risk factors include excess dietary sodium, obesity, excess alcohol, physical inactivity, family history, Afro-Caribbean ethnicity (earlier onset, higher prevalence), and chronic kidney disease. It accounts for more cardiovascular morbidity and mortality globally than any other single risk factor.
Clinical Features
Symptoms
Usually asymptomatic — found incidentally on routine measurement
Headache (typically occipital, worse in morning) — more common in severe hypertension
Visual disturbance (blurred vision, scotomata)
Epistaxis (in severe cases)
Chest pain or dyspnoea (suggesting end-organ damage)
Confusion, seizures (hypertensive encephalopathy)
Signs
Elevated clinic BP on repeated measurement
Fundoscopy: arteriolar narrowing, AV nipping (grade I–II), flame haemorrhages, cotton wool spots (grade III), papilloedema (grade IV — malignant hypertension)
S4 gallop (stiff, hypertrophied ventricle)
Loud A2 (aortic component of second heart sound)
Radio-femoral delay (coarctation of aorta — secondary cause)
Abdominal bruit (renal artery stenosis — secondary cause)
Investigations
First-line
ABPM (gold standard for diagnosis)≥2 readings/hour during waking hours. Use average of ≥14 daytime readings. Diagnostic threshold ≥135/85 mmHg
HBPM (if ABPM not tolerated)2 readings 1 min apart, BD for 4–7 days. Discard day 1. Diagnostic threshold ≥135/85 mmHg
BloodsU&Es (baseline renal function, K⁺), HbA1c, lipid profile, FBC
Second-line
Urine ACRScreen for proteinuria / diabetic nephropathy
12-lead ECGLVH (Sokolow-Lyon or Cornell criteria), ischaemic changes
QRISK310-year cardiovascular risk assessment — determines statin threshold (≥10%)
FundoscopyAssess for hypertensive retinopathy
Specialist
Renal ultrasound and DopplerIf suspected renal artery stenosis (young female, resistant HTN, renal bruit)
24-hour urinary catecholamines / metanephrinesIf phaeochromocytoma suspected (paroxysmal HTN, palpitations, sweating, headache)
Aldosterone:renin ratioIf Conn syndrome suspected (hypokalaemia + resistant HTN)
1
Step 1
- Age <55 (or any age with T2DM): ACE inhibitor (ramipril 1.25–10 mg OD) or ARB (candesartan, losartan) if ACEi not tolerated
- Age ≥55 OR Afro-Caribbean (any age): calcium channel blocker (amlodipine 5–10 mg OD)
- Consider ARB over ACEi for Afro-Caribbean patients
2
Step 2 — combine
- ACEi/ARB + CCB (most common combination)
- OR ACEi/ARB + thiazide-like diuretic (indapamide 2.5 mg OD)
3
Step 3 — triple therapy
- ACEi/ARB + CCB + thiazide-like diuretic (indapamide)
4
Step 4 — resistant hypertension
- Confirm resistant HTN with ABPM/HBPM, check adherence and postural BP
- If K⁺ ≤4.5 mmol/L: add low-dose spironolactone 25 mg OD
- If K⁺ >4.5 mmol/L: add alpha-blocker (doxazosin) or beta-blocker (bisoprolol)
- Seek specialist advice if uncontrolled on 4 drugs
Complications
- Stroke: Ischaemic and haemorrhagic — hypertension is the single most important modifiable risk factor
- Coronary heart disease: Accelerated atherosclerosis, MI, angina
- Heart failure: LVH → diastolic dysfunction → HFpEF; eventually systolic failure
- Chronic kidney disease: Hypertensive nephrosclerosis, proteinuria
- Hypertensive retinopathy: Graded I–IV; papilloedema = malignant hypertension = emergency
- Aortic dissection: Hypertension is the most common predisposing factor
- Peripheral arterial disease: Accelerated limb ischaemia
UKMLA Exam Tips
- 1ABPM is the gold standard for diagnosis — threshold is ≥135/85, NOT the clinic threshold of 140/90
- 2Step 1 drug choice depends on age AND ethnicity: <55 or T2DM = ACEi/ARB; ≥55 or Afro-Caribbean = CCB
- 3Spironolactone is the Step 4 drug of choice (if K⁺ ≤4.5) — classic exam question on resistant hypertension
- 4Do NOT combine ACEi + ARB (dual RAAS blockade → hyperkalaemia, renal failure)
- 5Young patient (<40) with hypertension → think secondary causes: renal artery stenosis, phaeochromocytoma, Conn syndrome, coarctation
- 6Stage 3 (≥180/120) with papilloedema or retinal haemorrhages = malignant hypertension → same-day specialist referral
practicetest your knowledge on hypertensionApply what you've learnt with UKMLA-style questions from the iatroX Q-Bank — cardiovascular and beyond.
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