High blood pressure (hypertension) affects more than 45 million Americans and is the commonest reason by an adult to visit the physician's office. Hypertension is a medical term used to describe increased pressure in the arterial system that transports blood from the heart to rest of the body. It is the force exerted by flowing blood on the wall of the arteries. Blood pressure originates mainly from a combination pumping force of the heart and resistance of the blood vessels to flow. Blood pressure is expressed as two numbers, systolic blood pressure and diastolic blood pressure. The systolic blood pressure is caused at the time of pumping of the heart and is higher number than diastolic blood pressure which occurs during the relaxation phase of the heart's pumping cycle. Systolic blood pressure usually written above the diastolic blood pressure (like 130/85). The values are expressed as mm of mercury. In the previous example the systolic blood pressure is said to be 130 mm of mercury and the diastolic pressure is 85 mm of mercury. When one is having blood pressure above the normal limit he or she is said to have hypertension or high blood pressure.
The following table explains normal and abnormal blood pressure
| Condition | Systolic blood pressure | Diastolic blood pressure |
| Normal | Less than 120 | Less than 80 |
| Pre-hypertension | 120 to 139 | 80 to 89 |
| Stage 1 hypertension | 140 to 159 | 90 to 99 |
| Stage 2 hypertension | 160 or higher | 100 or higher |
Comments: Among systolic and diastolic values, the value that is most abnormal will be used for the assessment of stage of hypertension (for example if systolic blood pressure is 138 and diastolic blood pressure is 101 he or she has stage 2 hypertension).
The exact reason why most people develop high blood pressure is unknown. However in about 2% of patients with hypertension a cause may be found. The causes in these people may include disease of the kidneys or adrenal glands. People with high blood pressure from these causes often may have significantly high levels of blood pressure. Diseases of thyroid glands cause also cause high blood pressure. Coarctation of aorta, (a congenital narrowing of the aorta in the chest) may be associated with increased blood pressure in the hands with decrease blood pressure in the legs. It is important to understand that in about 98% percentage of people with high blood pressure no cause can be found.
What are the risk factors for hypertension?
The following are risk factors for developing hypertension
- Having close relative with hypertension
- Male gender
- Black race
- Age above 35 years
- Diabetes
- Kidney disease
- Smoking
- Obesity
- Sleep apnea
- Taking oral contraceptive pills
- Excess alcohol use
- Lack of exercise
The answer is "yes". There are several things that can decrease your chances of developing high blood pressure. These include:
- Develop a healthy eating habit
- Maintain ideal body weight
- Have a regular exercise program
- Keep alcohol to moderation
- Reduce salt intake in your diet
- Stop smoking
High blood pressure causes damage to the blood vessels. High blood pressure can increase your risk of having a heart attack or stroke. It can cause extra stress to your heart, which can eventually fail to perform its function adequately (a condition known as heart failure). It can cause damage to kidneys causing decreased efficiency of renal function. It can also cause some neurologic and cardiovascular diseases:
- Neurologic - Hypertensive encephalopathy, cerebral vascular accident/cerebral infarction. subarachnoid hemorrhage, intracranial hemorrhage
- Cardiovascular - Myocardial ischemia/infarction, acute left ventricular dysfunction, acute pulmonary edema, aortic dissection
- Other - Retinopathy, eclampsia, microangiopathic hemolytic anemia
As mentioned above, untreated blood pressure can damage organs like kidney, heart or brain hence it is essential that you take measures to lower the blood pressure and minimize potential damage from other harmful living habits. Maintaining ideal body weight and having a regular program of exercise are integral parts of the treatment of high blood pressure. You should resort to healthy eating habits and cut down on fat. You should abstain from smoking and limit your alcohol intake to moderation. Many times the control of high blood pressure may require use of medications. The medications should be continued as long as your blood pressure remains high. With life style modifications your blood pressure may disappear and you may be able to stop taking the medications.
