Frequently Asked Questions About High Blood Pressure
Here are answers to your frequently asked questions about hypertension, commonly called high blood pressure.
1. What Causes High Blood Pressure?
While the cause of high blood pressure in most people remains unclear, a variety of conditions -- such as getting little or no exercise, poor diet, obesity, older age, and genetics -- can contribute to the development of hypertension.
2. What Is Systolic and Diastolic Blood Pressure?
The blood pressure reading is measured in millimeters of mercury (mmHg) and is written as systolic pressure, the force of the blood against the artery walls as your heart beats, over diastolic pressure, the blood pressure between heartbeats. For example, a blood pressure reading is written as 120/80 mmHg, or "120 over 80". The systolic pressure is 120 and the diastolic pressure is 80.
3. What Is a Normal Blood Pressure?
The Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure has classified blood pressure measurements into several categories:
- Normal blood pressure is systolic pressure less than 120 and diastolic pressure less than 80 mmHg.
- "Prehypertension" is systolic pressure of 120-139 or diastolic pressure of 80-89 mmHg.
- Stage 1 Hypertension is blood pressure greater than systolic pressure of 140-159 or diastolic pressure of 90-99 mmHg or greater.
- Stage 2 Hypertension is systolic pressure of 160 or greater or diastolic pressure of 100 or greater.
4. What Health Problems Are Associated With High Blood Pressure?
Several potentially serious health conditions are linked to high blood pressure, including:
- Atherosclerosis: a disease of the arteries caused by a buildup of plaque, or fatty material, on the inside walls of the blood vessels; hypertension contributes to this buildup by putting added stress and force on the artery walls.
- Heart Disease: Heart failure (the heart is not strong enough to pump blood adequately), ischemic heart disease (the heart tissue doesn't get enough blood), and hypertensive hypertrophic cardiomyopathy (thickened, abnormally functioning heart muscle) are all associated with high blood pressure.
- Kidney Disease: Hypertension can damage the blood vessels and filters in the kidneys, so that the kidneys cannot excrete waste properly.
- Stroke: Hypertension can lead to stroke, either by contributing to the process of atherosclerosis (which can lead to blockages and/or clots), or by weakening the blood vessel wall and causing it to rupture.
- Eye Disease: Hypertension can damage the very small blood vessels in the retina.
5. How Do I Know if I Have High Blood Pressure?
High blood pressure often doesn't have any symptoms, so you usually don't feel it. For that reason, hypertension is usually diagnosed by a health care professional during a routine checkup. If you have a close relative with hypertension, or other risk factors, it is especially important to pay attention to your blood pressure reading.
If your blood pressure is extremely high, you may have unusually strong headaches, chest pain, difficulty breathing, or poor exercise tolerance. If you have any of these symptoms, seek an evaluation immediately.