Arterial hypertension
Arterial hypertension, or high blood pressure is a medical condition where the blood pressure is chronically elevated. Persistent hypertension is one of the risk factors for strokes and heart attacks and is a leading cause of kidney failure.
Signs and symptoms
Hypertension does not normally present with any symptoms. It is commonly detected through "case finding" by doctors. Malignant hypertension (or accelerated hypertension) is a distinct condition, which presents with headaches, blurred vision and end-organ damage.
Definition
Hypertension is currently defined as a blood pressure above 140/90 mmHg measured on both arms at two instances (several weeks apart). Recently there have been calls to define blood pressure over 120/80 as "pre-hypertension".
Diagnosis
Over 90% of all hypertension has no known cause and is therefore called "essential/primary hypertension". Often, it is part of the Syndrome X in patients with insulin resistance: it occurs in combination with diabetes mellitus (type 2), combined hyperlipidemia and central obesity.
Important causes of secondary hypertension are:
Blood tests commonly performed in a newly diagnosed hypertension patient are:
Epidemiology
The level of blood pressure regarded as deleterious has been revised down during years of epidemiological studies. A widely quoted and important series of such studies is the Framingham, Massachusetts. The results from Framingham and of similar work in Busselton, Western Australia have been widely applied. To the extent that people are similar this seems reasonable, but there are known to be genetic variations in the most effective drugs for particular sub-populations.
Hypertension is often confused with mental tension, stress and anxiety. While chronic anxiety is associated with poor outcomes in people with hypertension, it alone does not cause it. Furthermore, relaxation therapy and biofeedback do little if anything to control blood pressure.
Treatment
Doctors recommend weight loss and regular exercise as the first step in treating mild to moderate hypertension. Both of these steps are highly effective in reducing blood pressure. Unfortunately these actions are easier to suggest that to achieve and most patients with moderate or severe hypertension end up requiring indefinite drug therapy to bring their blood pressure down to a safe level.
Mild hypertension is usually treated by diet, exercise and improved physical fitness. A diet rich in fruits and vegetables and fat-free dairy foods and low in fat and sodium lowers blood pressure in people with hypertension. Dietary sodium (salt) causes hypertension in some people and reducing salt intake decreases blood pressure in a third of people. Regular mild exercise improves blood flow, and helps to lower blood pressure. Decreasing or stopping of smoking reduces the damage done by smoking and may prevent the need for medication.
There are many medications for treating hypertension, together called antihypertensives, which—by varying means—act by lowering blood pressure. Evidence suggests that reduction of the blood pressure by 10 mmHg can decrease the risk for complications by about 25%.
In the ALLHAT trial, the diuretic hydrochlorothiazide was found to be the most effective antihypertensive medication in terms of reduction in risk of heart attacks and strokes. ACE inhibitors and calcium channel blockers were found to have no effect on these outcomes. Results in patients treated with Alpha blockers but not diuretics were found to be definitely less good (heart failure was more likely) and this arm of the trial was terminated early.
According to a recent , 1.0% of the adult American population ( p9) use complementary and alternative medicine to treat hypertension.
Complications
