Hypertension or high blood pressure is a chronic medical condition in which the blood pressure in the arteries is higher than it should be. This requires the heart to work harder than normal to circulate blood through the blood vessels.
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The pressure in the arteries changes depending on what the heart is doing. When the heart squeezes, pumping blood into the arteries, the pressure increases. When the heart relaxes, the pressure decreases. When blood pressure is measured, the highest pressure (when the heart is squeezing) is called the systolic blood pressure. The lowest pressure (when the heart is relaxing) is called the diastolic blood pressure.
Blood pressure is written as two numbers. For example, in the picture at the right, the person's systolic blood pressure was 158. Their diastolic blood pressure was 99. This blood pressure is written as 158/99. It is said "158 over 99."
Types of hypertensionEdit
There are two types of hypertension, called “primary” and “secondary.” Primary hypertension means that the hypertension is not caused by any other disease. Secondary hypertension means that the hypertension is caused by another disease. In most cases (90-95%), hypertension is primary. Only a small amount of hypertension (5-10%) is secondary.
Problems caused by hypertensionEdit
Hypertension can cause many problems, including heart attack, stroke, congestive heart failure, and kidney failure. To stay healthy, most people should try to keep their blood pressure below 140/90 mmHg.
- Lose weight if they are overweight or obese
- Exercise regularly
- Decrease the amount of salt they eat
- Limit the amount of alcohol they drink
- Eat a lot of fruits and vegetables
If lifestyle changes do not decrease a person's blood pressure, then the person may need medications. A doctor will choose which medications to use, based on what other medical problems the person has. Examples of medications that decrease blood pressure include:
- Diuretics, which increase urination to get rid of extra fluid
- Beta blockers, which slow down the heart rate
- ACE inhibitors, which relax the arteries
Even small decreases in blood pressure can have a large effect on a person's health. For example, decreasing blood pressure by 5 mmHg (for example, from 150/100 to 145/95 mmHg) can decrease the risk of stroke by 34%. It can also decrease the risk of heart disease by 21%.
- Arguedas, JA; Perez, MI; Wright, JM (Jul 8, 2009). Arguedas, Jose Agustin. ed. "Treatment blood pressure targets for hypertension". Cochrane Database of Systematic Reviews (3): CD004349. doi:10.1002/14651858.CD004349.pub2. PMID 19588353.
- Williams, B; Poulter, NR, Brown, MJ, Davis, M, McInnes, GT, Potter, JF, Sever, PS, McG Thom, S, British Hypertension, Society (March 2004). "Guidelines for management of hypertension: report of the fourth working party of the British Hypertension Society, 2004-BHS IV". Journal of Human Hypertension 18 (3): 139–85. doi:10.1038/sj.jhh.1001683. PMID 14973512
- Law M, Wald N, Morris J (2003). "Lowering blood pressure to prevent myocardial infarction and stroke: a new preventive strategy". Health Technol Assess 7 (31): 1–94. PMID 14604498.