High Blood Pressure

Hypertension
Classification and external resources
Automated arm heart rate of 80 beats per minute).
10	12, 15
9	401
OMIM	145500
DiseasesDB	6330
MedlinePlus	000468
eMedicine	med/1106 ped/1097 emerg/267
MeSH	D006973

Hypertension (HTN) or high blood pressure, sometimes called arterial hypertension, is a chronic medical condition in which the blood pressure in the arteries is elevated.^[1] This requires the heart to work harder than normal to circulate blood through the blood vessels. Blood pressure is summarised by two measurements, systolic and diastolic, which depend on whether the heart muscle is contracting (systole) or relaxed between beats (diastole). Normal blood pressure at rest is within the range of 100-140mmHg systolic (top reading) and 60-90mmHg diastolic (bottom reading). High blood pressure is said to be present if it is persistently at or above 140/90 mmHg.

Hypertension is classified as either primary (essential) hypertension or secondary hypertension; about 90–95% of cases are categorized as “primary hypertension” which means high blood pressure with no obvious underlying medical cause.^[2] The remaining 5–10% of cases (secondary hypertension) are caused by other conditions that affect the kidneys, arteries, heart or endocrine system.

Hypertension is a major life expectancy. Dietary and lifestyle changes can improve blood pressure control and decrease the risk of associated health complications, although drug treatment is often necessary in people for whom lifestyle changes prove ineffective or insufficient.

[edit] Signs and symptoms

Hypertension is rarely accompanied by any symptoms, and its identification is usually through [4]

On [3]

[edit] Secondary hypertension

Some additional signs and symptoms may suggest [6]

[edit] Hypertensive crisis

Severely elevated blood pressure (equal to or greater than a systolic 180 or diastolic of 110 — sometime termed malignant or accelerated hypertension) is referred to as a “hypertensive crisis”, as blood pressures above these levels are known to confer a high risk of complications. People with blood pressures in this range may have no symptoms, but are more likely to report headaches (22% of cases)^[8]

A “hypertensive emergency”, previously “malignant hypertension”, is diagnosed when there is evidence of direct damage to one or more organs as a result of the severely elevated blood pressure. This may include [8]

[edit] In pregnancy

Hypertension occurs in approximately 8-10% of pregnancies.^[9]

[edit] In infants and children

[10]

[edit] Cause

[edit] Primary hypertension

Primary (essential) hypertension is the most common form of hypertension, accounting for 90–95% of all cases of hypertension.^[23]

[edit] Secondary hypertension

Secondary hypertension results from an identifiable cause. Renal disease is the most common secondary cause of hypertension.^[25]

[edit] Pathophysiology

In most people with established [32]

[34]

Many mechanisms have been proposed to account for the rise in peripheral resistance in hypertension. Most evidence implicates either disturbances in renal salt and water handling (particularly abnormalities in the intrarenal [38]

[edit] Diagnosis

Typical tests performed

System	Tests
Renal	creatinine
Endocrine	Serum TSH
Metabolic	triglycerides
Other	chest radiograph
Sources: Harrison’s principles of internal medicine[44]

Hypertension is diagnosed on the basis of a persistently high blood pressure. Traditionally,^[47]

Once the diagnosis of hypertension has been made, physicians will attempt to identify the underlying cause based on risk factors and other symptoms, if present. Secondary hypertension is more common in preadolescent children, with most cases caused by renal disease. Primary or essential hypertension is more common in adolescents and has multiple risk factors, including obesity and a family history of hypertension.^[48] Laboratory tests can also be performed to identify possible causes of secondary hypertension, and to determine whether hypertension has caused damage to the heart, eyes, and kidneys. Additional tests for diabetes and high cholesterol levels are usually performed because these conditions are additional risk factors for the development of heart disease and may require treatment.^[2]

Serum [6]

[edit] Adults

Classification (JNC7)[1]	Systolic pressure		Diastolic pressure
	mmHg	kPa	mmHg	kPa
Normal	90–119	12–15.9	60–79	8.0–10.5
Prehypertension	120–139	16.0–18.5	80–89	10.7–11.9
Stage 1 hypertension	140–159	18.7–21.2	90–99	12.0–13.2
Stage 2 hypertension	?160	?21.3	?100	?13.3
Isolated systolic hypertension	?140	?18.7	<90	<12.0

In people aged 18 years or older hypertension is defined as a systolic and/or a diastolic blood pressure measurement consistently higher than an accepted normal value (currently 139 mmHg systolic, 89 mmHg diastolic: see table —Classification (JNC7)). Lower thresholds are used (135 mmHg systolic or 85 mmHg diastolic) if measurements are derived from 24-hour ambulatory or home monitoring.^[1]

[edit] Children

Hypertension in [11]

Hypertension occurs quite commonly in children and adolescents (2-9% depending on age, sex and ethnicity)^[52]

[edit] Prevention

Much of the disease burden of high blood pressure is experienced by people who are not labelled as hypertensive.^[54] for the primary prevention of hypertension:

• maintain normal body weight for adults (e.g. body mass index 20–25 kg/m²)
• reduce dietary sodium intake to <100 mmol/ day (<6 g of sodium chloride or <2.4 g of sodium per day)
• engage in regular aerobic physical activity such as brisk walking (?30 min per day, most days of the week)
• limit alcohol consumption to no more than 3 units/day in men and no more than 2 units/day in women
• consume a diet rich in fruit and vegetables (e.g. at least five portions per day);

Effective lifestyle modification may lower blood pressure as much an individual antihypertensive drug. Combinations of two or more lifestyle modifications can achieve even better results.^[53]

[edit] Management

[edit] Lifestyle modifications

The first line of treatment for hypertension is identical to the recommended preventative lifestyle changes^[60]

Dietary change such as a [62]

[edit] Medications

Several classes of medications, collectively referred to as [64]

If drug treatment is initiated the Joint National Committee on High Blood Pressure (JNC-7)^[67]

Guidelines on the choice of agents and how best to step up treatment for various subgroups have changed over time and differ between countries. The best first line agent is disputed.^[68]

[edit] Drug combinations

The majority of people require more than one drug to control their hypertension. JNC7^[72]

[edit] In the elderly

Treating moderate to severe hypertension decreases death rates and cardiovascular [70]

[edit] Resistant hypertension

Resistant hypertension is defined as hypertension that remains above goal blood pressure in spite of concurrent use of three antihypertensive agents belonging to different antihypertensive drug classes. Guidelines for treating resistant hypertension have been published in the UK^[76]

[edit] Epidemiology

As of 2000, nearly one billion people or ~26% of the adult population of the world had hypertension.^[79]

In 1995 it was estimated that 43 million people in the United States had hypertension or were taking antihypertensive medication, almost 24% of the adult United States population.^[2]

[edit] In children

The prevalence of high blood pressure in the young is increasing.^[85]

[edit] Prognosis

Hypertension is the most important [1]

[edit] History

Modern understanding of the cardiovascular system began with the work of physician [90]

Historically the treatment for what was called the “hard pulse disease” consisted in reducing the quantity of blood by [94]

[edit] Society and culture

[edit] Awareness

[96]

[edit] Economics

High blood pressure is the most common chronic medical problem prompting visits to primary health care providers in USA. The American Heart Association estimated the direct and indirect costs of high blood pressure in 2010 as $76.6 billion.^[99]

[edit] References

[edit] External links

Wikimedia Commons has media related to: Hypertension

• Hypertension at the Open Directory Project

v t e 440–456) arterioles and capillaries Inflammation Arteritis (Aortitis) · Buerger’s disease Arterial occlusive disease/ peripheral vascular disease Arteriosclerosis trans fat) Stenosis Renal artery stenosis · Carotid artery stenosis Other Erythromelalgia dissection/ pseudoaneurysm torso: Coronary artery aneurysm head/neck: Familial aortic dissection Vascular malformation Hereditary hemorrhagic telangiectasia) Vascular nevus Cherry hemangioma Veins Inflammation Phlebitis Venous thrombosis/ Thrombophlebitis primarily lower limb (Deep vein thrombosis) abdomen (Renal vein thrombosis) upper limb/torso (Mondor’s disease) head (Cerebral venous sinus thrombosis) Post-thrombotic syndrome Varicose veins Caput medusae) Other Chronic cerebrospinal venous insufficiency Arteries or veins Microangiopathy) Blood pressure Hypertension Hypertensive heart disease · Hypertensive nephropathy · Essential hypertension  · Secondary hypertension (Renovascular hypertension) · Pulmonary hypertension · Malignant hypertension · Benign hypertension · Systolic hypertension · White coat hypertension Hypotension Orthostatic hypotension VAS prot injr 9)

 

 

 

Source: Wikipedia