A look at the causes of high blood pressure

There are two types of high blood pressure - essential (or primary) hypertension and secondary hypertension. When a patient's high blood pressure has no known or identifiable causes, he or she is said to have essential hypertension. Secondary hypertension refers to high blood pressure that occurs as a result of other problems like tumors, kidney disorders, etc. Of the two, essential hypertension is far more common.

Hypertension is often associated with one or more environmental or other factors. What follows is a look at the factors that have the ability to affect blood pressure levels.

The most well known factor is sensitivity to sodium. It has been estimated that fully 60% of those with essential hypertension respond positively to reduction in salt intake. High salt intake changes the sodium-potassium balance in the body. This results in the body drawing more water, which in turn causes greater pressure within the blood vessels.

Limiting salt consumption is one of the first things the doctor will advise hypertensive patients to do. Excess salt consumption may be one of the common causes of high blood pressure. However, many people who consume plenty of salt do not develop hypertension.

Genetics plays a significant role in this condition and it thought to be among the causes of high blood pressure. Several studies - on animals and human beings - show that there are many different genetic factors that contribute to hypertension. In other words, this condition is not the result of just one single genetic defect. Well over fifty genes have been studied for their connection with high blood pressure.

Insulin resistance is thought to play a role in developing elevated blood pressure. Insulin is secreted by the pancreas and it regulates the levels of glucose in the body through a complex process involving negative feedback mechanisms. Insulin has vasodilatory effects, which should normally act to lower blood pressure. In some cases, other processes may negate these vasodilatory properties and can cause elevated blood pressure. Insulin resistance is considered to be one of the causes of high blood pressure in certain individuals.

The kidneys secrete a hormone called renin. High renin levels act to increase blood pressure. It creates vasoconstriction and causes sodium to be reabsorbed in the kidneys. Higher sodium levels correlate with elevated blood pressure. At the same time, many patients with hypertension have low levels of renin. This is particularly true of African Americans. These patients often respond well to diuretic drugs to lower blood pressure.

Sleep apnea can be one of the causes of high blood pressure. Patients with apnea have their sleep interrupted a few hundred times each night due to a temporary cessation of breathing. This continual interference with sleep disrupts the normal sleep cycles and the patient does not spend enough time in deep, restorative sleep. This causes many health problems, one of which is high blood pressure.

Age is often a factor behind hypertension. As a person ages, the walls of the arteries and arterioles become layered with increasing amounts of collagen fibers. This results in the blood vessels losing their elasticity. The fiber accumulation also results in a decrease in the cross section area of blood vessels. These vessels therefore have a lower volume to transport blood through, which causes blood pressure to go up.

The final causes of high blood pressure are not fully understood. Ongoing research efforts continue to extract more clues about what underlies this dangerous condition.

© 2007-2008 HypertensionHelp.net. All rights reserved worldwide. Unauthorized duplication prohibited.