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Nephrology and Urology· Topic 9.4 Hypertension of renal and endocrine origin· 9.4.1
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Essential hypertension

Essential (primary) hypertension is chronically elevated blood pressure without an identifiable secondary cause, the overwhelming majority of hypertension. It is a leading modifiable driver of stroke, heart failure, and kidney disease, and management combines lifestyle change with staged pharmacotherapy to a target usually below 130/80 mmHg.

6 min readReviewed 2026-07-19

Key facts

Definition
Sustained high blood pressure with no secondary cause
Diagnostic threshold
>=130/80 mmHg (confirmed, out-of-office preferred)
Share of cases
About 90-95% of all hypertension
Usual target
<130/80 mmHg for most adults
First-line drugs
Thiazide, ACEi/ARB, or calcium channel blocker
Foundation
Lifestyle: sodium, weight, alcohol, exercise, DASH diet
Key harms
Stroke, coronary disease, heart failure, CKD

Overview

  • Definition: essential (primary) hypertension is chronically elevated arterial blood pressure with no single identifiable secondary cause, arising from the interaction of genetic and environmental factors.
  • Cardinal presentation: usually asymptomatic and detected on screening, with symptoms or complications appearing only in severe or long-standing disease.
  • Why it matters: it is one of the most common and modifiable causes of stroke, heart failure, coronary disease, and chronic kidney disease.

Epidemiology

  • Extremely common, affecting a large share of adults and rising with age.
  • Accounts for the great majority (about 90 to 95 percent) of hypertension.
  • A leading global contributor to cardiovascular death.

Risk factors

  • Age and family history.
  • Excess dietary sodium, obesity, and physical inactivity.
  • Excess alcohol and a diet low in potassium.
  • Diabetes, chronic kidney disease, and obstructive sleep apnea.

Pathophysiology

  • Increased vascular resistance: the hallmark, from arteriolar remodeling, endothelial dysfunction, and increased sympathetic and renin-angiotensin activity.
  • Sodium and volume handling: impaired renal sodium excretion raises volume and pressure.
  • Vascular stiffening: with age, large-artery stiffening raises systolic pressure and pulse pressure.
  • Target-organ injury: sustained pressure damages the brain, heart, kidneys, retina, and vasculature.

Clinical features

  • Usually asymptomatic (the "silent killer").
  • Nonspecific symptoms (headache) only with markedly elevated pressure.
  • Signs of target-organ damage: left ventricular hypertrophy, retinopathy, and proteinuria.
  • Presentation via a complication: stroke, myocardial infarction, or heart failure.

Differential diagnosis

  • Secondary hypertension: an identifiable, often correctable cause such as aldosteronism or renal artery stenosis, distinguished by positive cause-specific testing (an abnormal aldosterone-renin ratio, renovascular imaging) that is absent in essential hypertension (Secondary hypertension).
  • White-coat hypertension: elevated office readings, distinguished by normal ambulatory or home monitoring.
  • Masked hypertension: normal office readings, distinguished by elevated ambulatory or home readings despite a normal clinic value.
  • Resistant hypertension: uncontrolled hypertension, distinguished by persistent elevation despite three agents including a diuretic at maximally tolerated doses (Resistant hypertension).
  • Isolated systolic hypertension: age-related arterial stiffening, distinguished by an elevated systolic pressure with a normal or low diastolic pressure and a wide pulse pressure.
  • Pseudohypertension: falsely high cuff readings from noncompressible calcified arteries, distinguished by a positive Osler maneuver and discrepancy with intra-arterial pressure.
  • Anxiety or pain: transient elevation, distinguished by normalization once the provoking stimulus resolves.
  • Measurement error: wrong cuff size or technique, distinguished by normal values on properly performed repeat measurement.

Diagnosis

  • Establish by repeated, properly measured blood pressure at or above 130/80 mmHg, confirmed with out-of-office readings, after excluding secondary causes: the diagnostic basis is accurate, repeated measurement (ideally confirmed by ambulatory or home monitoring) meeting the threshold, with initial evaluation for target-organ damage and screening for secondary causes when features suggest them.
  • First step, accurate repeated blood pressure measurement: correct cuff and technique, confirmed on separate occasions.
  • Then confirm with out-of-office monitoring: ambulatory or home readings to exclude white-coat and detect masked hypertension.
  • Then assess target-organ damage and risk: ECG, urinalysis and renal function, lipids, glucose, and fundoscopy, and estimate cardiovascular risk.
  • Screen for secondary causes when clinical features, young age, or resistance suggest them.

Clinical pearl. Confirm hypertension with out-of-office readings before committing a patient to lifelong therapy: white-coat hypertension is common, and treating an office-only elevation exposes patients to unnecessary drugs and hypotension, while masked hypertension (normal in clinic, high at home) is missed without it.

Management

  • First-line, begin lifestyle modification for all: sodium restriction (under 1.5 to 2.3 g/day), weight loss, the Dietary Approaches to Stop Hypertension (DASH) diet, regular aerobic exercise, and limiting alcohol, which can substantially lower pressure.
  • Then start pharmacotherapy based on level and risk:
    • Thiazide-type diuretic (chlorthalidone 12.5 to 25 mg PO daily), continued long term.
    • ACE inhibitor (lisinopril 10 to 40 mg PO daily) or an ARB (losartan 50 to 100 mg PO daily), continued long term.
    • Calcium channel blocker (amlodipine 5 to 10 mg PO daily), continued long term.
  • If blood pressure is 20/10 mmHg above target or remains uncontrolled, start or escalate to two agents (commonly an ACE inhibitor or ARB plus a calcium channel blocker such as amlodipine 5 to 10 mg PO daily or a thiazide), preferably as a single-pill combination.
  • Target usually below 130/80 mmHg for most adults, individualized in the frail elderly.
  • Then treat comorbidities and add agents in sequence (adding a mineralocorticoid antagonist such as spironolactone 25 mg PO daily for resistant cases) with monitoring of electrolytes and renal function.

Complications

  • Stroke and hypertensive encephalopathy.
  • Coronary artery disease, left ventricular hypertrophy, and heart failure.
  • Chronic kidney disease.
  • Retinopathy, aortic aneurysm and dissection, and peripheral artery disease.

Prognosis

  • Excellent with sustained control, which markedly reduces cardiovascular events.
  • Risk rises continuously with the level of untreated pressure.
  • Worse with target-organ damage and coexisting risk factors.

Prevention

  • Maintain a healthy weight and DASH-style diet.
  • Limit sodium (under 1.5 to 2.3 g/day) and alcohol and ensure adequate potassium.
  • Regular aerobic exercise and smoking cessation.
  • Screen blood pressure periodically for early detection.

Key points

  • Essential hypertension is sustained high blood pressure with no secondary cause.
  • Diagnose at 130/80 mmHg or above, confirmed with out-of-office readings.
  • It is usually asymptomatic but a leading cause of stroke, heart failure, and CKD.
  • Lifestyle change is foundational; first-line drugs are thiazides, ACEi/ARB, or calcium channel blockers.
  • The usual target is below 130/80 mmHg.

Practice questions

Board-style vignettes on this article, free with it. Pick an answer to see why each choice is right or wrong.

Vignette
A 45-year-old man comes to the office for a preemployment physical examination. He feels well. No prior blood pressure measurements are available. He has no coronary artery disease or known hypokalemia. He takes no medications or supplements and does not smoke. Temperature is 36.8 °C, seated blood pressure 148/94 mm Hg in both arms with an appropriately sized cuff, pulse rate 72/min, respiration rate 14/min and oxygen saturation 98% on ambient air. BMI is 26. The fundi show no arteriolar narrowing or arteriovenous nicking. The point of maximal impulse is not displaced, and there is no S4. No abdominal or flank bruit is heard. Which of the following is the most appropriate next diagnostic test?
Vignette
A 52-year-old woman comes to the office after an elevated health fair blood pressure reading. She takes no medications and does not smoke. She has no cardiovascular disease or diabetes. Two weeks ago, her office blood pressure averaged 136/92 mm Hg on 2 seated readings with correct technique. Home readings twice daily for 1 week average 133/91 mm Hg. Temperature is 36.7 °C, blood pressure 132/92 mm Hg (2-visit office average, 134/92 mm Hg), pulse rate 76/min, respiration rate 14/min and oxygen saturation 98% on ambient air. Cardiac examination is normal. Serum electrolytes, creatinine, urinalysis and ECG are normal. Estimated 10-year ASCVD risk is 6%. Which of the following is the most appropriate management?
Vignette
A 61-year-old man is evaluated in the office for hypertension diagnosed 4 months ago, when his estimated 10-year ASCVD risk was 14%. Lisinopril was started and increased to 40 mg daily 6 weeks ago. Pharmacy records show on-time refills, and home readings average 135/84 mm Hg. He has no diabetes, kidney disease, or heart disease. He had a gout flare of the great toe 2 years ago and takes no urate-lowering therapy. Temperature is 36.7 °C (98.1 °F), blood pressure is 136/85 mm Hg, pulse rate is 74/min, respiration rate is 14/min, oxygen saturation is 98% breathing ambient air, and BMI is 29. Examination is normal. Which of the following is the most appropriate next step in management?
Vignette
A 55-year-old Black man comes to the office to discuss treatment of hypertension. Office readings at 2 visits 3 weeks apart average 144/88 mm Hg, and 24-hour ambulatory monitoring shows a daytime average of 142/87 mm Hg. He has reduced his sodium intake and walks daily. He has no diabetes, heart failure, myocardial infarction, arrhythmia or urinary hesitancy and takes no medications. Temperature is 36.8 °C, blood pressure 144/88 mm Hg, pulse rate 74/min, respiration rate 14/min and oxygen saturation 98% on ambient air. BMI is 27. Cardiopulmonary examination is normal. Serum creatinine and electrolytes are normal, and urinalysis shows no protein. In addition to continued lifestyle modification, which of the following is the most appropriate initial drug therapy?
Vignette
A 47-year-old woman is evaluated in the office for elevated blood pressure found at 2 visits this month. Office readings averaged 154/96 mm Hg, and her 2-week home log from a validated monitor averages 150/94 mm Hg. Two years ago her blood pressure was 134/86 mm Hg. She has dull headaches at the end of some workdays that resolve with acetaminophen. She takes no medications. Temperature is 36.8 °C (98.2 °F), blood pressure is 152/96 mm Hg, pulse rate is 76/min, respiration rate is 14/min, and oxygen saturation is 99% on ambient air. BMI is 31. Funduscopic, cardiac and abdominal examinations are normal. Which of the following is the most appropriate initial diagnostic evaluation?
Vignette
A 76-year-old woman comes to the office for a routine visit. Three weeks ago her blood pressure averaged 164/78 mm Hg on 2 seated readings. Systolic pressure was 138 mm Hg 6 years ago and 148 mm Hg 3 years ago. She has no palpitations, sweating, heat intolerance, fatigue or weight change. She has never smoked and takes no medications. Temperature is 36.7 °C, blood pressure 160/74 mm Hg, pulse rate 72/min, respiration rate 14/min and oxygen saturation 97% on ambient air. There is no goiter, lid lag or abdominal bruit. Serum potassium is 4.2 mEq/L, bicarbonate 25 mEq/L and creatinine 0.9 mg/dL; urinalysis is normal. Which of the following best explains the mechanism of her hypertension?
Vignette
high-yield
A 58-year-old woman is evaluated in the office for elevated blood pressure; a walk-in clinic recorded 148/94 mm Hg during a migraine 4 weeks ago. Since then, office readings at 3 visits average 134/82 mm Hg, and validated home readings average 133/83 mm Hg. She has type 2 diabetes mellitus treated with metformin. Temperature is 36.8 °C (98.2 °F), blood pressure is 134/82 mm Hg, pulse rate is 72/min, respiration rate is 14/min, oxygen saturation is 98% breathing ambient air, and BMI is 29. Examination is normal. Hemoglobin A1c is 6.8% (normal, 4.0%-5.6%), urine albumin-creatinine ratio is 12 mg/g (normal, <30 mg/g), and metabolic panel is normal. Estimated 10-year atherosclerotic cardiovascular risk is 17%. Which of the following is the most appropriate management?
Vignette
high-yield
A 48-year-old woman is evaluated in the office for elevated blood pressure since a workplace screening 2 months ago. Office readings at 2 visits average 132/84 mm Hg, and validated home readings average 131/83 mm Hg. She has no diabetes, kidney disease, or cardiovascular disease and takes no medications. She does not smoke and drinks 1 glass of wine weekly. Her mother has hypertension. Temperature is 36.7 °C (98.1 °F), blood pressure is 132/84 mm Hg, pulse rate is 68/min, respiration rate is 14/min, oxygen saturation is 98% on ambient air, and BMI is 28. Examination, metabolic panel, urinalysis, and ECG are normal. Estimated 10-year ASCVD risk is 4%. Which of the following is the most appropriate management?
Vignette
high-yield
A 57-year-old man is evaluated in the office for follow-up of hypertension diagnosed 1 year ago. Home readings over the past 2 weeks average 146/90 mm Hg. He takes lisinopril 20 mg daily and has missed no doses. He has followed a low-sodium diet for 6 months and drinks 4 beers most evenings. He wants to cut back on alcohol and asks how much he may drink. Temperature is 36.8 °C (98.2 °F), blood pressure is 148/92 mm Hg, pulse rate is 78/min, respiration rate is 14/min, and oxygen saturation is 98% on ambient air. BMI is 24. Examination is normal. Metabolic panel is normal. Which of the following is the recommended maximum alcohol intake for this patient?

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