Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long term high blood pressure, however, is a major risk factor for coronary artery disease, stroke, heart failure, peripheral vascular disease, vision loss, and chronic kidney disease. High blood pressure is classified as either primary (essential) high blood pressure or secondary high blood pressure. About 90% of cases are primary, defined as high blood pressure due to nonspecific lifestyle changes, chronic stress, environmental and family habits and genetic factors. Lifestyle factors that increase the risk include excess salt, excess body weight, smoking, and alcohol. The remaining 5% of cases are categorized as secondary high blood pressure, defined as high blood pressure due to an identifiable cause, such as chronic kidney disease, narrowing of the kidney arteries, an endocrine disorder like diabetes especially affecting the kidneys, other hormonal factors and the use of birth control pills.