High blood pressure is a 'risk factor' for developing a cardiovascular disease (such as a heart attack or stroke), and kidney damage, sometime in the future. If you have high blood pressure, over the years it may have a damaging effect to arteries and put a strain on your heart. In general, the higher your blood pressure, the greater the health risks. But, high blood pressure is just one of several possible risk factors for developing a cardiovascular disease.

If those temporary episodes occur frequently, they can cause just as much damage to your blood vessels, heart and kidneys as can chronic high blood pressure. In addition, when you have anxiety, you're more likely to resort to other unhealthy habits, such as smoking, drinking or overeating - which, in turn, can increase your risk of high blood pressure.

Even if high blood pressure does cause symptoms, the symptoms are usually mild and nonspecific (vague, or suggesting many different disorders).

Malignant hypertension may be associated with headache, light-headedness, or nausea.

Certain nerve impulses cause your arteries to dilate (become larger) or contract (become smaller). If these vessels are wide open, blood can flow through easily. If they're narrow, it's harder for the blood to flow through them, and the pressure inside them increases. Then high blood pressure may occur. When this happens, your heart becomes strained and blood vessels may become damaged. Changes in the vessels that supply blood to your kidneys and brain may cause these organs to be affected.

In 90-95 percent of cases, scientists don't know what causes high blood pressure. This is essential hypertension. Fortunately, although scientists don't fully understand the causes of this disease, they've developed both non-drug and drug treatments that treat it effectively. They've also identified some factors that contribute to higher blood pressure. These are arteriosclerosis (or hardening of the arteries), thickening or hypertrophy of the artery wall, and excess contraction of the arterioles (small arteries).

Essential hypertension affects approximately 75 million Americans, yet its basic causes or underlying defects are not always known. Nevertheless, certain associations have been recognized in people with essential hypertension. For example, essential hypertension develops only in groups or societies that have a fairly high intake of salt, exceeding 5.8 grams daily. In fact, salt intake may be a particularly important factor in relation to essential hypertension in several situations.

Hypertension is referred to as essential (primary) when the doctor is unable to identify a specific cause. It is by far the most common type of high blood pressure. The causes of this type are unknown but are likely to be a complex combination of genetic, environmental, and other factors.

The cause of high blood pressure often cannot be found in many teens with hypertension. When the cause is unknown, a person has what's called essential or primary hypertension. In cases where the cause of high blood pressure is known (called secondary hypertension), it is usually the result of kidney problems, hormonal disorders, abnormalities of the aorta (the main artery that carries oxygenated blood to the body), or a narrowing of certain smaller arteries. Most teens that are diagnosed with hypertension have essential hypertension.