What is hypertension
Executive summary
Hypertension, commonly called high blood pressure, is a persistent elevation of the force of blood against arterial walls that increases risk of heart attack, stroke, kidney disease and other organ damage [1][2][3]. Definitions and treatment thresholds vary between major authorities, but the condition is common, often symptomless, and usually diagnosed by repeated blood-pressure measurements [4][3][5].
1. What hypertension is, in plain terms
Hypertension means the pressure of blood pushing on the walls of arteries is consistently higher than what is healthy for the body; blood pressure is recorded as two numbers—systolic (pressure during a heartbeat) over diastolic (pressure between beats)—and elevated, persistent readings indicate hypertension [1][2][6]. Because most people feel no different when blood pressure is high, the only reliable way to know is measurement with validated devices, ideally confirmed on more than one occasion [1][3].
2. How clinicians label and measure it — a contested yardstick
Authoritative groups disagree on exact cutoffs: the 2017 ACC/AHA guidelines lowered hypertension to systolic ≥130 mm Hg or diastolic ≥80 mm Hg, while many international bodies such as the World Health Organization and European societies use a higher diagnostic threshold of 140/90 mm Hg for office measurements [4][7][3][8]. Clinical practice therefore hinges on context—single high readings prompt rechecks, ambulatory or home monitoring can clarify true blood pressure, and the target for treatment is often individualized based on overall cardiovascular risk [3][7].
3. Two broad types: primary (essential) and secondary
About 90–95% of cases are primary or essential hypertension, which develops gradually and reflects complex interactions of genetics, aging and lifestyle factors such as excess salt, obesity, physical inactivity, smoking and alcohol use [9][7]. The remaining 5–10% is secondary hypertension, where a specific and sometimes treatable cause—kidney disease, hormonal disorders, certain medications or vascular narrowing—drives the high readings [9][7].
4. The health toll and how common it is
Hypertension is a leading contributor to cardiovascular disease worldwide and is implicated in heart attacks, strokes, heart failure, chronic kidney disease, vision loss and cognitive decline [9][3][10]. Prevalence estimates depend on the definition used; for example, U.S. estimates rose when thresholds were lowered, and global and regional surveillance show stagnant or slowly rising prevalence in many places, with many people remaining unaware or untreated [5][11][9].
5. Treatment, prevention and when to act urgently
Management combines lifestyle measures—salt reduction, weight loss, regular activity, reduced alcohol and smoking cessation—with medications when indicated; treatment goals and the need for drugs depend on blood-pressure level and overall risk of cardiovascular disease [1][12][6]. Blood pressures above about 180/120 mm Hg can signal a hypertensive emergency requiring immediate medical care if accompanied by organ-damaging symptoms; otherwise urgent assessment is advised [12][13].
6. Where guidance is clear and where the reporting gaps remain
Medical consensus is clear that sustained high arterial pressure harms organs and that measurement, awareness and control matter, but guidance diverges on numerical thresholds and treatment intensity—reflecting tradeoffs between preventing events and exposing people to lifelong medications [4][8][7]. Existing sources describe causes, outcomes and population trends well, but this reporting cannot resolve individual treatment choices or substitute for personalized clinical assessment; those decisions require clinicians to weigh guideline differences against patient-specific risk [7][4].