Hypertension is defined as a persistently elevated blood pressure, typically clinic BP ≥140/90 mmHg confirmed by ABPM/HBPM (≥135/85 mmHg). 👉 In around 90–95% of cases the cause is essential (primary) hypertension – a multifactorial, polygenic condition with no single reversible cause. 👉 Secondary hypertension (renal, endocrine, vascular and drug-related causes) accounts for about 5–10% and should be considered in younger patients, resistant hypertension, or when specific clinical clues are present.

⚠️ Risk Factors for Essential Hypertension

🌍 Ethnicity: higher prevalence and severity in Black and some East Asian (e.g. Japanese) populations
🧬 Family history and polygenic inheritance
🧂 High dietary salt intake and 🍷 excess alcohol consumption
⚖️ Obesity, particularly central adiposity, and 🛋 sedentary lifestyle
👶 Adverse intrauterine environment (low birth weight, impaired early growth)
🧠 Chronic stress, poor sleep and psychosocial factors

🔎 Clinical Clues to Secondary Hypertension

🦵 Radio–femoral delay, differential arm/leg pressures or ejection systolic murmur → coarctation of the aorta
🎧 Abdominal/renal bruit, flash pulmonary oedema → renal artery stenosis
👁 Acromegalic facies or Cushingoid appearance → endocrine hypertension (GH excess, Cushing’s)
😰 Episodic headache, sweating, pallor, tremor, palpitations → phaeochromocytoma/paraganglioma
🫘 Bilateral flank masses, early CKD → polycystic kidney disease
💊 Resistant HTN on ≥3 drugs, or sudden loss of control → consider renal, endocrine, vascular or iatrogenic causes (e.g. NSAIDs, steroids)

🚨 Complications of Long-Term Hypertension

👁 Hypertensive retinopathy (Grades I–IV)
❤️ Left ventricular hypertrophy → forceful/displaced apex, diastolic dysfunction
🌬 Heart failure → pulmonary oedema, reduced exercise tolerance
🧠 Stroke (ischaemic and haemorrhagic) and vascular dementia
🧪 Chronic kidney disease with proteinuria and progressive loss of GFR
💔 Coronary artery disease, myocardial infarction and sudden cardiac death
⚡ Atrial fibrillation secondary to LA enlargement and LVH
🦵 Peripheral arterial disease and aortic aneurysm/dissection

🩺 Accurate BP Measurement (Key Principles)

✅ Use the correct cuff size (too small = overestimation; too large = underestimation)
🚭 Avoid smoking, caffeine or vigorous exercise for at least 30 minutes before measurement
🪑 Patient seated, back supported, feet flat, rested for ≥5 minutes; arm supported at heart level
🔁 Take at least two readings on each occasion; repeat on two or more visits where safe to do so
🫀 Measure both arms at least once; if difference ≥15–20 mmHg persists, investigate further
📊 Ambulatory BP monitoring (ABPM) or validated HBPM is recommended to confirm diagnosis and detect “white-coat” or masked hypertension

📊 Grading of Hypertension (ACC/AHA Office BP – for Comparison)

Note: This table uses US (ACC/AHA) thresholds based on clinic BP. UK/NICE uses a diagnostic threshold of ≥140/90 mmHg (confirmed by ABPM/HBPM) and does not label 130–139/80–89 as hypertension.

Grade	Systolic (mmHg)	Diastolic (mmHg)	Clinical Significance
✅ Normal	<120	<80	Maintain healthy lifestyle; reassess routinely
⚠️ Elevated	120–129	<80	Increased future risk; focus on lifestyle and monitoring
🟡 Stage 1	130–139	80–89	Lifestyle; consider meds if high CV risk or target organ damage
🟠 Stage 2	140–159	90–99	Typically requires medication plus lifestyle measures
🔴 Stage 3 (severe)	≥160	≥100	Markedly raised risk; urgent optimisation and close follow-up
🚨 Hypertensive crisis	≥180	≥120	Consider hypertensive emergency if target organ damage → same-day admission

👁 Hypertensive Retinopathy (Keith–Wagener–Barker Classification)

Grade	Fundoscopic Findings	Clinical Significance
1	Generalised arteriolar narrowing, “copper wiring”	Often asymptomatic; early marker of systemic HTN
2	Arteriovenous (AV) nicking / “nipping”	Reflects more established vascular damage; ↑ CV risk
3	Retinal haemorrhages, exudates, cotton wool spots	Severe retinopathy; high risk of stroke/MI
4 🚨	Grade 3 changes + papilloedema	Malignant hypertension; medical emergency

🧪 Baseline Investigations in Hypertension

🩸 Fasting or non-fasting glucose & lipids → metabolic syndrome, cardiovascular risk
🧪 U&E, creatinine, eGFR → renal function and baseline before ACEi/ARB/diuretics
🧾 Urinalysis ± ACR → proteinuria/haematuria (CKD, secondary causes)
📈 ECG → LVH, AF, prior infarction, conduction abnormalities
🫀 Echocardiogram if heart failure suspected or unexplained LVH
🩻 Additional tests guided by suspicion of secondary causes (renin/aldosterone, catecholamines, renal imaging, endocrine work-up)

📑 BHS / NICE-Aligned Stepwise Drug Therapy (ABCD Rule)

Simplified UK-style algorithm – always individualise for co-morbidities and local guidance.

Step	Age <55 & non-Black	Black ethnicity or Age ≥55
1	A: ACE inhibitor or ARB	C or D: CCB or thiazide-like diuretic
2	A + (C or D)	C + (A or D)
3	Triple therapy (A + C + D)	Triple therapy (A + C + D)
4	Add α-blocker, β-blocker, or spironolactone (or specialist input)	Same (individualise to co-morbidities and tolerability)

🥗 Lifestyle Measures (First-Line for All Patients)

⚖️ Weight loss if overweight or obese
🚭 Smoking cessation (major reduction in overall CV risk)
🥦 Diet: high in fruit/veg, whole grains; low salt and saturated fat
🍷 Limit alcohol; avoid binge drinking
🏃 Regular aerobic exercise (e.g. ≥150 min/week of moderate activity if able)
🛌 Improve sleep and manage stress (CBT, relaxation, mindfulness where appropriate)

💊 Common Antihypertensive Drug Classes

Class	Example	Typical Dose Range	Mechanism	Key Notes
🧬 ACE inhibitor	Ramipril	2.5–10 mg OD	↓ Ang II → vasodilation; ↓ aldosterone	Renoprotective in diabetes; cough, angioedema; monitor U&E and K⁺
🧬 ARB	Losartan	50–100 mg OD	Blocks AT1 receptor	Alternative if ACEi intolerant; similar monitoring needs
💊 CCB (dihydropyridine)	Amlodipine	5–10 mg OD	Blocks L-type Ca²⁺ channels → vasodilation	Good in elderly/Black patients; ankle oedema, flushing, headache
💊 Thiazide-like diuretic	Indapamide	1.5 mg MR OD or 2.5 mg OD	Inhibits Na⁺ reabsorption in distal tubule	Useful in older patients; watch Na⁺/K⁺, uric acid and glucose
💊 β-blocker	Atenolol / Bisoprolol	Atenolol 25–100 mg OD; Bisoprolol 2.5–10 mg OD	↓ Sympathetic drive to heart & kidneys	Not first-line for uncomplicated HTN; useful in IHD, arrhythmias, HF
💊 Aldosterone antagonist	Spironolactone	25–50 mg OD	Blocks aldosterone in distal nephron	Role in resistant HTN; risk hyperkalaemia, gynaecomastia; monitor K⁺

💡 Clinical Pearls

👵 In patients ≥80 years, titrate slowly and avoid over-zealous lowering to reduce falls and cerebral hypoperfusion.
🧑‍⚕️ Always reconsider secondary causes in resistant HTN, onset <40 years, or abrupt loss of control.
📊 ABPM/HBPM is more reliable than isolated clinic readings; use it wherever possible.
🧠 Think “organ protection”: the goal is preventing stroke, MI, CKD and retinopathy, not just hitting a numeric target.

🩺 Case 1 — Newly Diagnosed, Young Patient

A 42-year-old man has clinic BP 152/94 mmHg on three visits, ABPM confirms average 145/90 mmHg. He has BMI 28, no end-organ damage, and no diabetes. Management: Emphasise lifestyle (weight loss, diet, exercise, reduced alcohol). As a <55-year-old non-Black patient with persistent stage 2 HTN, an ACE inhibitor (e.g. ramipril) is usually first-line if no contraindications. Avoid: Starting treatment without confirming diagnosis; ACEi in women of childbearing potential without appropriate counselling.

🩺 Case 2 — Middle-Aged, Symptomatic Patient

A 58-year-old woman has headaches and average clinic BP 168/100 mmHg. She has type 2 diabetes and microalbuminuria. Management: Immediate pharmacological therapy with an ACE inhibitor or ARB (renal protection in diabetes), plus lifestyle measures. If uncontrolled, add a CCB and/or thiazide-like diuretic. Monitor BP and renal function closely. Avoid: β-blockers as first-line in uncomplicated HTN; NSAIDs where possible, as they can worsen BP and renal function.

🩺 Case 3 — Elderly with Isolated Systolic Hypertension

An 80-year-old man has home BP readings around 168/72 mmHg. He has HFpEF, preserved renal function and no diabetes. Management: Treatment is indicated; a dihydropyridine CCB (e.g. amlodipine) is often first choice in older patients. Titrate slowly and consider adding a thiazide-like diuretic if needed, aiming for a cautious target (e.g. <145/85 mmHg if tolerated). Avoid: Aggressive BP lowering that provokes postural hypotension or falls; ACEi/ARB in significant renal impairment without specialist advice.

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Essential Hypertension