Causes of Primary Hypertension
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, while unknown, are likely to be a complex combination of genetic, environmental, and other factors.[For risk factors of developing primary hypertension, see the Risk Factors section of this report.]
Genetic Factors. A number of genetic factors or interactions between genes play a major role in essential hypertension. Genes under investigation include:
- Genes that regulate a group of hormones known collectively as the angiotensin-renin-aldosterone system. This system influences all aspects of blood pressure control, including blood vessel contraction, sodium and water balance, and cell development in the heart.
- Genes that cause abnormalities of the sympathetic nervous system. This is the part of the autonomic nervous system that controls heart rate, blood pressure, and the diameter of the blood vessels.
Causes of Secondary Hypertension
Secondary hypertension is caused by an underlying medical condition or other factor (such as medications) that elevates blood pressure. Many different medical conditions are associated with secondary hypertension. These conditions can also make high blood pressure more difficult to control. They include:
Review Date: 04/06/2010
Reviewed By: Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.