Hypertension (High Blood Pressure)

Definition and measurement

Blood pressure is recorded as two numbers (systolic/diastolic) measured in millimeters of mercury (mm Hg). Diagnostic thresholds vary by guideline: some organizations define hypertension at 130/80 mm Hg or higher, while others use 140/90 mm Hg. Accurate diagnosis usually requires repeated readings, proper cuff size and technique, and often ambulatory or home monitoring to confirm persistent elevation rather than a temporary rise due to stress or activity. Learn about measurement methods at reliable guidance.

Causes and risk factors

Hypertension is categorized as primary (essential) when no single cause is identified, or secondary when it results from another condition. Common contributors and risk factors include:

• Age, family history, and genetic predisposition
• Excess body weight, physical inactivity, high-sodium diet
• Excessive alcohol intake and tobacco use
• Underlying conditions such as chronic kidney disease, sleep apnea, endocrine disorders, or certain medications

Complications and clinical significance

Unchecked hypertension damages arteries and organs over time. It raises the risk of heart attack, stroke, heart failure, kidney failure, peripheral arterial disease and eye damage (hypertensive retinopathy). Severity can escalate to hypertensive emergency, when very high pressure causes acute organ injury.

Diagnosis, management and prevention

Management aims to lower pressure to safer targets and reduce cardiovascular risk. Lifestyle measures are foundational: weight reduction, regular aerobic exercise, dietary approaches such as reduced sodium and the DASH diet, limiting alcohol, and quitting smoking. When indicated, medications from several classes — including diuretics, ACE inhibitors, angiotensin receptor blockers (ARBs), calcium channel blockers and beta-blockers — are used alone or in combination. Choice depends on patient characteristics, comorbidities and tolerability.

Screening and treatment of hypertension are essential public-health strategies because the condition is common worldwide and largely manageable. For clinical guidelines and care pathways consult clinical resources and public health summaries at health agencies.