Blood pressure is the force exerted by circulating blood against the walls of blood vessels, essential for delivering oxygen and nutrients throughout the body. It is measured in millimeters of mercury (mm Hg) and recorded as two numbers: systolic pressure (the upper number, when the heart beats) and diastolic pressure (the lower number, when the heart rests between beats)
Blood Pressure Categories
The American Heart Association and other health organizations categorize blood pressure as follows:
Category| Systolic (mm Hg)| Diastolic (mm Hg)
---|---|---
Normal| Less than 120| Less than 80
Elevated| 120–129| Less than 80
High Blood Pressure Stage 1| 130–139| 80–89
High Blood Pressure Stage 2| 140 or higher| 90 or higher
Hypertensive Crisis (emergency)| Higher than 180| Higher than 120
If the systolic and diastolic numbers fall into different categories, the higher category is used for diagnosis. For example, a reading of 125/85 mm Hg is considered Stage 1 hypertension
Health Implications
- High blood pressure (hypertension) increases the risk of serious health problems such as heart attack, stroke, heart failure, and chronic kidney disease
- Low blood pressure (hypotension) is generally defined as below 90/60 mm Hg and can cause symptoms like dizziness or fainting
- Nearly half of U.S. adults have high blood pressure, often without symptoms, so regular measurement is crucial
Managing Blood Pressure
- Lifestyle changes such as diet, exercise, weight management, and reducing salt intake are first-line strategies, especially for elevated and Stage 1 hypertension
- Medication may be recommended for Stage 1 hypertension if there is a history of heart attack, stroke, or a high 10-year cardiovascular risk, or for Stage 2 hypertension
- In hypertensive crisis (above 180/120 mm Hg), immediate medical attention is necessary, especially if accompanied by symptoms like chest pain or difficulty speaking
Regular monitoring and consultation with healthcare professionals are essential to maintain blood pressure within a healthy range and prevent complications
