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Hypertension, also referred to as high blood pressure, HTN or HPN, is a medical
condition in which the blood pressure is chronically elevated. In current usage, the word "hypertension" without a qualifier normally refers to systemic, arterial hypertension. Hypertension can be classified either essential (primary) or secondary. Essential hypertension indicates that no specific medical cause can be found to explain a patient's condition. Secondary hypertension indicates that the high blood pressure is a result of (i.e., secondary to) another condition, such as kidney disease or tumours (pheochromocytoma and paraganglioma). Persistent hypertension is one of the risk factors for strokes, heart attacks, heart failure and arterial aneurysm, and is a leading cause of chronic renal failure. Even moderate elevation of arterial blood pressure leads to shortened life expectancy. At severely high pressures, defined as mean arterial pressures 50% or more above average, a person can expect to live no more than a few years unless appropriately treated. In individuals older than 50 years, hypertension is considered to be present when a person's systolic blood pressure is consistently 140 mm Hg or greater or when the diastolic blood pressure is consistently 90 mm Hg or greater. Beginning at a systolic pressure of 115 and diastolic pressure of 75 (commonly written as 115/75 mm Hg), cardiovascular disease (CVD) risk doubles for each increment of 20/10 mmHg. Prehypertension is defined as blood pressure from 121/81 mm Hg to 139/89 mm Hg. Prehypertension is not a disease category; rather, it is a designation chosen to identify individuals at high risk of developing hypertension. The Mayo Clinic specifies that blood pressure is normal if it is 120/80 or below. Patients with blood pressures over 130/80 mm Hg along with Type 1 or Type 2 diabetes, or kidney disease require further treatment. Resistant hypertension is defined as the failure to reduce BP to the appropriate level after taking a three-drug regimen. The American Heart Association released guidelines for treating resistant hypertension. |
