Hypertension 77432 225850250 2008-07-15T18:12:47Z 12.226.105.223 Changed a revision in which a recent study was replaced by an older study. To be fair, both are now present. {{Infobox_Disease | Name = Hypertension | Image = | Caption = | DiseasesDB = 6330 | ICD10 = {{ICD10|I|10||i|10}},{{ICD10|I|11||i|10}},{{ICD10|I|12||i|10}},<br>{{ICD10|I|13||i|10}},{{ICD10|I|15||i|10}} | ICD9 = {{ICD9|401.x}} | ICDO = | OMIM = 145500 | MedlinePlus = 000468 | eMedicineSubj = med | eMedicineTopic = 1106 | eMedicine_mult = {{eMedicine2|ped|1097}} {{eMedicine2|emerg|267}} | MeshID = D006973 | }} {{otheruses4||other forms of hypertension}} {{contradict|section}} {{Expert-verify|date=June 2008}} '''Hypertension''', referred to as '''high blood pressure''', '''HTN''' or '''HPN''', is a medical condition in which the [[blood pressure]] is chronically elevated. It was previously referred to as '''nonarterial hypertension'''{{Fact|date=June 2008}}, but in current usage, the word "hyper''tension''"{{Fact|date=June 2008}} without a qualifier normally refers to [[artery|arterial]] hypertension. <ref>{{cite book | last = Maton | first = Anthea | authorlink = | coauthors = Jean Hopkins, Charles William McLaughlin, Susan Johnson, Maryanna Quon Warner, David LaHart, Jill D. Wright | title = Human Biology and Health | publisher = Prentice Hall | date = 1993 | location = Englewood Cliffs, New Jersey, USA | pages = | url = | doi = | id = | isbn = 0-13-981176-1}}</ref> 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 [[stroke]]s, [[myocardial infarction|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 pressure]]s 50% or more above average, a person can expect to live no more than a few years unless appropriately treated.<ref>{{cite book |title=Textbook of Medical Physiology |edition=7th Ed. |author=Guyton & Hall |publisher=Elsevier-Saunders |isbn=0-7216-0240-1 |pages=p220}}</ref> Hypertension is considered to be present when a person's [[systole (medicine)|systolic]] blood pressure is consistently 140&nbsp;[[Torr|mmHg]] or greater, and/or their [[diastole|diastolic]] blood pressure is consistently 90&nbsp;mmHg or greater.<ref>[http://www.nlm.nih.gov/cgi/mesh/2007/MB_cgi?mode=&index=6693 Hypertension] - [[Medical Subject Headings|MeSH]]</ref> As recently as 2003, the ''Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure''<ref name="jnc7">{{ cite journal |url=http://jama.ama-assn.org/cgi/content/full/289.19.2560v1 |author=Chobanian AV et al |journal=[[Journal of the American Medical Association|JAMA]] |title=The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: the JNC 7 report. |year = 2003 |volume = 289 |pages = 2560-72 |pmid = 12748199 }}</ref> has defined blood pressure 120/80 mmHg to 139/89 mmHg as "[[prehypertension]]." Prehypertension is not a disease category; rather, it is a designation chosen to identify individuals at high risk of developing hypertension. The [http://www.mayoclinic.com/health/high-blood-pressure/DS00100/DSECTION=6 Mayo Clinic website]specifies blood pressure is "normal if it's below 120/80" but that "some data indicate that 115/75 mm Hg should be the gold standard." In patients with [[diabetes mellitus]] or [[Nephropathy|kidney disease]] studies have shown that blood pressure over 130/80 mmHg should be considered high and warrants further treatment. Hypertension is labeled '''resistant''' or '''refractory'''<ref>[www.cfps.org.sg/sfp/29/292/29(2)_20-22.pdf REFRACTORY HYPERTENSION. By Dr Teo Wee Siong] Singapore Family Physician APR - JUN 2003 ; VOL 29 (2) : 2 </ref> if a person’s blood pressure remains above their target blood pressure despite taking three or more medications to lower it. The [[American Heart Association]] released a scientific statement<ref>{{cite web|title= American Heart Association scientific statement: New guidelines issued for treating resistant hypertension| url= http://hyper.ahajournals.org/cgi/reprint/HYPERTENSIONAHA.108.189141 }}</ref> in May 2008 with guidelines for treating resistant hypertension.<ref>{{cite web|title=Guidelines for treating resistant hypertension| url= http://www.my-blood-pressure.com/aha-guidelines.html}}</ref> == Factors of essential hypertension == Although no specific medical cause can be determined in essential hypertension, the most common form has several contributing factors. These include salt sensitivity, renin [[human homeostasis|homeostasis]], insulin resistance, genetics, and age. === Liquorice === Consumption of [[liquorice]] (which can be of ''potent'' strength in [[Liquorice (confectionery)|liquorice candy]]) can lead to a surge in blood pressure. People with hypertension or history of cardio-vascular disease should avoid liquorice raising their blood pressure to risky levels. Frequently, if liquorice is the cause of the high blood pressure, a low blood level of potassium will also be present. Liquorice extracts are present in many medicines (for example cough syrups, [[throat lozenge]]s and peptic ulcer treatments). === Sodium sensitivity === [[Salt#Health effects|Sodium]] is an environmental factor that has received the greatest attention. Approximately one third of the essential hypertensive population is responsive to sodium intake<ref>http://www.jstage.jst.go.jp/article/jphs/100/5/370/_pdf A Missing Link Between a High Salt Intake and Blood Pressure Increase: Makoto Katori and Masataka Majima, Department of Pharmacology, Kitasato University School of Medicine, Kitasato, Sagamihara, Kanagawa, Japan February 8, 2006</ref>. This is due to the fact that increasing amounts of salt in a person's bloodstream causes cells to release water (due to osmotic pressure) to equilibrate concentration gradient of salt between the cells and the bloodstream; increasing the pressure on the blood vessel walls. === Role of renin === [[Renin]] is an [[enzyme]] secreted by the [[juxtaglomerular apparatus]] of the kidney and linked with [[aldosterone]] in a negative feedback loop. The range of renin activity observed in hypertensive subjects tends to be broader than in [[normotensive]] individuals. In consequence, some hypertensive patients have been defined as having low-renin and others as having essential hypertension. Low-renin hypertension is more common in [[African American]]s than [[white American]]s, and may explain why [[African American]]s tend to respond better to diuretic therapy than drugs that interfere with the renin-angiotensin system. High Renin levels predispose to Hypertension: Increased Renin → Increased [[Angiotensin II]] → Increased [[Vasoconstriction]], Thirst/[[ADH]] and [[Aldosterone]] → Increased [[Sodium]] Resorption in the [[Kidney]]s (DCT and CD) → Increased [[Blood Pressure]]. According to the Fifth Edition Annotated Instructor's Edition Nutrition Concepts & Controversies by authors, Eva May Nunnelley Hamilton, M.S., Eleanor Noss Whitney, Ph.d, R.D., Frances Sienkiewicz Sizer, M.S., R.D.published by West Publishing Company 1991 ISBN 0-314-81092-7 "Some authorities believe that potassium might both prevent and treat hypertension. It goes on to advise that salt avoidance may assist in lowering blood pressure in two ways, one of which is by replacing highly processed (salted foods) with natural foods which contain higher levels of potassium, and the other is by reducing salt intake. === Insulin resistance === [[Insulin]] is a polypeptide [[hormone]] secreted by cells in the [[islets of langerhans]], which are contained throughout the [[pancreas]]. Its main purpose is to regulate the levels of [[glucose]] in the body [[antagonistic]]ally with [[glucagon]] through [[negative feedback]] loops. Insulin also exhibits vasodilatory properties. In normotensive individuals, insulin may stimulate sympathetic activity without elevating mean arterial pressure. However, in more extreme conditions such as that of the metabolic syndrome, the increased sympathetic neural activity may over-ride the vasodilatory effects of insulin. Insulin resistance and/or [[hyperinsulinemia]] have been suggested as being responsible for the increased arterial pressure in some patients with hypertension. This feature is now widely recognized as part of [[metabolic syndrome|syndrome X]], or the [[metabolic syndrome]]. === Sleep apnea === [[Sleep apnea]] is a common, under-recognized cause of hypertension.<ref name="Sleep Apnea">{{ cite journal |url=http://www.aafp.org/afp/20020115/229.html |author=Silverberg DS, Iaina A and Oksenberg A |journal=American Family Physicians |title=Treating Obstructive Sleep Apnea Improves Essential Hypertension and Quality of Life |year = 2002 |month = January |volume = 65 |issue = 2 |pages = 229-36 |pmid = 11820487 }}</ref> It is often best treated with nocturnal nasal [[CPAP|continuous positive airway pressure]], but other approaches include the [[Mandibular advancement splint]] (MAS), [[UPPP]], [[tonsilectomy]], [[adenoidectomy]], [[sinus surgery]], or weight loss. === Genetics === Hypertension is one of the most common complex disorders, with genetic [[heritability]] averaging 30%.{{Fact|date=November 2007}} Data supporting this view emerge from animal studies as well as in population studies in humans. Most of these studies support the concept that the inheritance is probably multifactorial or that a number of different genetic defects each have an elevated blood pressure as one of their [[phenotypic]] expressions. More than 50 genes have been examined in association studies with hypertension, and the number is constantly growing. === Age === Over time, the number of [[collagen]] fibers in artery and arteriole walls increases, making blood vessels stiffer. With the reduced elasticity comes a smaller cross-sectional area in systole, and so a raised mean arterial blood pressure. === Other etiologies === There are some anecdotal or transient causes of high blood pressure. These are not to be confused with the disease called hypertension in which there is an intrinsic physiopathological mechanism as described below. == Etiology of secondary hypertension == Only in a small minority of patients with elevated arterial pressure can a specific cause be identified. In 90 percent to 95 percent of high blood pressure cases, the American Heart Association says there's no identifiable cause. These individuals will probably have an [[endocrine]] or renal defect that, if corrected, could bring blood pressure back to normal values. ;Renal hypertension :Hypertension produced by diseases of the [[kidney]]. This includes diseases such as [[polycystic kidney disease]] or chronic [[glomerulonephritis]]. Hypertension can also be produced by diseases of the [[renal artery|renal arteries]] supplying the kidney. This is known as [[renovascular hypertension]]; it is thought that decreased perfusion of renal tissue due to [[stenosis]] of a main or branch renal artery activates the renin-angiotensin system. ;Adrenal hypertension :Hypertension is a feature of a variety of adrenal cortical abnormalities. In primary [[aldosteronism]] there is a clear relationship between the aldosterone-induced sodium retention and the hypertension. ;[[Cushing's syndrome]] (hypersecretion of cortisol) :Both adrenal glands can overproduce the hormone cortisol or it can arise in a benign or malignant tumor. Hypertension results from the interplay of several pathophysiological mechanisms regulating plasma volume, peripheral vascular resistance and cardiac output, all of which may be increased. More than 80% of patients with Cushing's syndrome have hypertension. :In patients with [[pheochromocytoma]] increased secretion of [[catecholamines]] such as [[epinephrine]] and [[norepinephrine]] by a tumor (most often located in the adrenal medulla) causes excessive stimulation of [adrenergic receptors], which results in peripheral vasoconstriction and cardiac stimulation. This diagnosis is confirmed by demonstrating increased urinary excretion of epinephrine and norepinephrine and/or their metabolites ([[vanillylmandelic acid]]). ;Genetic causes :Hypertension can be caused by mutations in single genes, inherited on a mendelian basis.<ref name=amn>{{cite web | Williams B et al; British Hypertension Society; Michael Sutters, MD | title = Hypertension Etiology & Classification - Secondary Hypertension | publisher=Armenian Medical Network | work = | url=http://www.health.am/hypertension/secondary-hypertension/ | year = 2006 | accessdate=2007-12-02}}</ref> ;[[Coarctation of the aorta]] ;Drugs :Certain medications, especially NSAIDS (Motrin/[[Ibuprofen]]) and steroids can cause hypertension. Licorice (''Glycyrrhiza glabra'') inhibits the 11-hydroxysteroid hydrogenase enzyme (catalyzes the reaction of cortisol to cortison) which allows cortisol to stimulate the Mineralocorticoid Receptor (MR) which will lead to effects similar to hyperaldosteronism, which itself is a cause of hypertension.<ref>Harrisons Internal Medicine, online edition (2007-04-14)</ref> ;Rebound hypertension :High blood pressure that is associated with the sudden [[withdrawal]] of various [[antihypertensive]] medications. The increases in blood pressure may result in blood pressures greater than when the medication was initiated. Depending on the severity of the increase in blood pressure, rebound hypertension may result in a [[hypertensive emergency]]. Rebound hypertension is avoided by gradually reducing the dose (also known as "dose tapering"), thereby giving the body enough time to adjust to reduction in dose. :Medications commonly associated with rebound hypertension include centrally-acting antihypertensive agents, such as [[clonidine]] and beta-blockers. == Pathophysiology == Most of the secondary mechanisms associated with hypertension are generally fully understood, and are outlined at [[secondary hypertension]]. However, those associated with essential (primary) hypertension are far less understood. What is known is that [[cardiac output]] is raised early in the disease course, with [[total peripheral resistance]] (TPR) normal; over time cardiac output drops to normal levels but TPR is increased. Three theories have been proposed to explain this: * Inability of the kidneys to excrete sodium, resulting in [[natriuretic]] factors such as [[Atrial Natriuretic Factor]] being secreted to promote salt excretion with the side-effect of raising total peripheral resistance. * An overactive [[renin / angiotensin system]] leads to [[vasoconstriction]] and retention of sodium and water. The increase in blood volume leads to hypertension. * An overactive [[sympathetic nervous system]], leading to increased stress responses. It is also known that hypertension is highly heritable and [[polygenic]] (caused by more than one gene) and a few candidate [[genes]] have been postulated in the etiology of this condition.<ref name="polymorphism">{{cite journal |author= Sagnella GA, Swift PA |journal=Current Pharmaceutical Design |title=The Renal Epithelial Sodium Channel: Genetic Heterogeneity and Implications for the Treatment of High Blood Pressure |year = 2006 |month = June |volume = 12 |issue = 14 |pages = 2221–2234 |pmid = 16787251 | doi = 10.2174/138161206777585157}}</ref><ref name="polymorphism2">{{cite journal |author= Johnson JA, Turner ST |journal=Current Opinion in Molecular Therapy |title=Hypertension pharmacogenomics: current status and future directions. |year = 2005 |month = June |volume = 7 |issue = 3 |pages = 218–225 |pmid = 15977418}}</ref><ref name="polymorphism3">{{cite journal|author= Hideo Izawa; Yoshiji Yamada et al |journal=Hypertension |title=Prediction of Genetic Risk for Hypertension |year = 2003 |month = May |volume = 41 |issue = 5 |pages = 1035–1040 |pmid = 12654703 | url=http://hyper.ahajournals.org/cgi/content/short/01.HYP.0000065618.56368.24v1 |doi=10.1161/01.HYP.0000065618.56368.24}}</ref> == Signs and symptoms == Hypertension is usually found incidentally - "case finding" - by healthcare professionals during a routine checkup. The only test for hypertension is a blood pressure measurement. Hypertension in isolation usually produces no symptoms although some people report headaches, fatigue, dizziness, blurred vision, facial flushing, transient insomnia or difficulty sleeping due to feeling hot or flushed, and [[tinnitus]] <ref>{{cite web|url=http://www.treatment-for.com/high-blood-pressure-symptoms.htm|title=Symptoms of High Blood Pressure}}</ref> during beginning onset or prior to hypertention diagnosis. [[Malignant hypertension]] (or accelerated hypertension) is distinct as a late phase in the condition, and may present with headaches, blurred vision and end-organ damage. Hypertension is often confused with mental tension, stress and anxiety. While chronic anxiety and/or irritability is associated with poor outcomes in people with hypertension, it alone does not cause it. Accelerated hypertension is associated with somnolence, confusion, visual disturbances, and nausea and vomiting (hypertensive encephalopathy). <ref name=health.am>{{cite web | H. Michael MacMay, MD, MPH; Michael Sutters, MD | title =Hypertension symptoms and signs | publisher=Armenian Medical Network | work =Systemic Hypertension - Hypertension Health Center | url=http://www.health.am/hypertension/hypertension-symptoms-and-signs/ | year = 2006 | accessdate=2007-07-24}}</ref> === Hypertensive urgencies and emergencies === Hypertension is rarely severe enough to cause symptoms. These typically only surface with a [[systolic blood pressure]] over 240 mmHg and/or a [[diastolic blood pressure]] over 120 mmHg. These pressures without signs of end-organ damage (such as renal failure) are termed "accelerated" hypertension. When end-organ damage is possible or already ongoing, but in absence of raised [[intracranial pressure]], it is called [[hypertensive emergency]]. Hypertension under this circumstance needs to be controlled, but prolonged hospitalization is not necessarily required. When hypertension causes increased intracranial pressure, it is called [[malignant hypertension]]. Increased intracranial pressure causes [[papilledema]], which is visible on [[ophthalmoscopy|ophthalmoscopic]] examination of the [[retina]]. === Complications === While elevated blood pressure alone is not an illness, it often requires treatment due to its short- and long-term effects on many organs. The risk is increased for: * [[Cerebrovascular accident]] (CVAs or strokes) * [[Myocardial infarction]] (heart attack) * [[Hypertensive cardiomyopathy]] ([[heart failure]] due to chronically high blood pressure) * [[Hypertensive retinopathy]] - damage to the [[retina]] * [[Hypertensive nephropathy]] - [[chronic renal failure]] due to chronically high blood pressure * [[Hypertensive encephalopathy]] - confusion, headache , convulsion due to vasogenic edema in brain due to high blood pressure. === Pregnancy === {{main|Hypertension of pregnancy}} Although few women of childbearing age have high blood pressure, up to 10% develop [[hypertension of pregnancy]]. While generally benign, it may herald three complications of pregnancy: [[pre-eclampsia]], [[HELLP syndrome]] and [[eclampsia]]. Follow-up and control with medication is therefore often necessary. ===Children and adolescents === As with adults, blood pressure is a variable parameter in children. It varies between individuals and within individuals from day to day and at various times of the day. The epidemic of [[childhood obesity]], the risk of developing left ventricular hypertrophy, and evidence of the early development of atherosclerosis in children would make the detection of and intervention in childhood hypertension important to reduce long-term health risks; however, supporting data are lacking. Most childhood hypertension, particularly in preadolescents, is secondary to an underlying disorder. Renal parenchymal disease is the most common (60 to 70%) cause of hypertension. Adolescents usually have primary or essential hypertension, making up 85 to 95% of cases. <ref name=aafp>{{cite web | GREGORY B. LUMA, M.D., and ROSEANN T. SPIOTTA, M.D., Jamaica Hospital Medical Center | title =Hypertension in Children and Adolescents | publisher=American Academy of Family Physicians | work =Hypertension in Children and Adolescents | url=http://www.aafp.org/afp/20060501/1558.html | year = 2006 | accessdate=2007-07-24}}</ref> == Diagnosis == ===Measuring blood pressure=== {{main|Blood pressure}} Diagnosis of hypertension is generally on the basis of a persistently high blood pressure. Usually this requires three separate measurements at least one week apart. Exceptionally, if the elevation is extreme, or end-organ damage is present then the diagnosis may be applied and treatment commenced immediately. Obtaining reliable blood pressure measurements relies on following several rules and understanding the many factors that influence blood pressure reading<ref name="pmid7707630">{{cite journal | author = Reeves R | title = The rational clinical examination. Does this patient have hypertension? How to measure blood pressure. | journal = JAMA | volume = 273 | issue = 15 | pages = 1211–8 | year = 1995 | pmid = 7707630 | doi = 10.1001/jama.273.15.1211}}</ref>. For instance, measurements in control of hypertension should be at least 1 hour after caffeine, 30 minutes after smoking or strenuous exercise and without any stress. Cuff size is also important. The bladder should encircle and cover two-thirds of the length of the (upper) arm. The patient should be sitting upright in a chair with both feet flat on the floor for a minimum of five minutes prior to taking a reading. The patient should not be on any adrenergic stimulants, such as those found in many cold medications. When taking manual measurements, the person taking the measurement should be careful to inflate the cuff suitably above anticipated systolic pressure. The person should inflate the cuff to 200 [[mmHg]] and then slowly release the air while palpating the radial pulse. After one minute, the cuff should be reinflated to 30 mmHg higher than the pressure at which the radial pulse was no longer palpable. A stethoscope should be placed lightly over the brachial artery. The cuff should be at the level of the heart and the cuff should be deflated at a rate of 2 to 3 mmHg/s. Systolic pressure is the pressure reading at the onset of the [[Korotkoff sound|sounds]] described by [[Nikolai Korotkoff|Korotkoff]] (Phase one). Diastolic pressure is then recorded as the pressure at which the sounds disappear (K5) or sometimes the K4 point, where the sound is abruptly muffled. Two measurements should be made at least 5 minutes apart, and, if there is a discrepancy of more than 5 mmHg, a third reading should be done. The readings should then be averaged. An initial measurement should include both arms. In elderly patients who particularly when treated may show [[orthostatic hypotension]], measuring lying sitting and standing BP may be useful. The BP should at some time have been measured in each arm, and the higher pressure arm preferred for subsequent measurements. BP varies with time of day, as may the effectiveness of treatment, and [[Medical informatics|archetypes]] used to record the data should include the time taken. Analysis of this is rare at present. Automated machines are commonly used and reduce the variability in manually collected readings <ref name="pmid2294682">{{cite journal | author = White W, Lund-Johansen P, Omvik P | title = Assessment of four ambulatory blood pressure monitors and measurements by clinicians versus intraarterial blood pressure at rest and during exercise. | journal = Am J Cardiol | volume = 65 | issue = 1 | pages = 60–6 | year = 1990 | pmid = 2294682 | doi = 10.1016/0002-9149(90)90026-W}}</ref>. Routine measurements done in medical offices of patients with known hypertension may incorrectly diagnose 20% of patients with uncontrolled hypertension <ref name="pmid16050862">{{cite journal | author = Kim J, Bosworth H, Voils C, Olsen M, Dudley T, Gribbin M, Adams M, Oddone E | title = How well do clinic-based blood pressure measurements agree with the mercury standard? | journal = J Gen Intern Med | volume = 20 | issue = 7 | pages = 647–9 | year = 2005 | pmid = 16050862 | doi = 10.1007/s11606-005-0112-6}}</ref> [[Home blood pressure monitoring]] can provide a measurement of a person's blood pressure at different times throughout the day and in different environments, such as at home and at work. Home monitoring may assist in the diagnosis of high or low blood pressure. It may also be used to monitor the effects of medication or lifestyle changes taken to lower or regulate blood pressure levels. Home monitoring of blood pressure can also assist in the diagnosis of [[white coat hypertension]]. The [[American Heart Association]]<ref>{{cite website| title= Home Monitoring of High Blood Pressure| author=The American Heart Association| url= http://www.americanheart.org/presenter.jhtml?identifier=576}}</ref> states, "You may have what's called 'white coat hypertension'; that means your blood pressure goes up when you're at the doctor's office. Monitoring at home will help you measure your true blood pressure and can provide your doctor with a log of blood pressure measurements over time. This is helpful in diagnosing and preventing potential health problems." Some home blood pressure monitoring devices also make use of blood pressure charting software.<ref>{{cite web|title=Blood pressure charting software| url=http://www.my-blood-pressure.com/abp-chart.html}}</ref> These charting methods provide printouts for the patient's physician and reminders to take a blood pressure reading. However, a simple and cheap way is simply to manually record values with pen and paper, which can then be inspected by a doctor. ===Distinguishing primary vs. secondary hypertension=== Once the diagnosis of hypertension has been made it is important to attempt to exclude or identify reversible (secondary) causes. * Over 91% of adult hypertension has no clear cause and is therefore called '''essential/primary hypertension'''. Often, it is part of the [[metabolic syndrome|metabolic "syndrome X"]] in patients with [[insulin resistance]]: it occurs in combination with [[diabetes mellitus]] (type 2), [[combined hyperlipidemia]] and [[central obesity]]. * [[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. <ref name="pmid16719248">{{cite journal | author = Luma GB, Spiotta RT | title = Hypertension in children and adolescents. | journal = Am Fam Physician | volume = 73 | issue = 9 | pages = 1558–68 | month = may | year = 2006 | pmid = 16719248}}</ref> ===Investigations commonly performed in newly diagnosed hypertension=== Tests are undertaken to identify possible causes of secondary hypertension, and seek evidence for end-organ damage to the heart itself or the eyes (retina) and kidneys. Diabetes and raised cholesterol levels being additional risk factors for the development of cardiovascular disease are also tested for as they will also require management. [[Blood test]]s commonly performed include: * [[Creatinine]] ([[renal function]]) - to identify both underlying renal disease as a cause of hypertension and conversely hypertension causing onset of kidney damage. Also a baseline for later monitoring the possible side-effects of certain antihypertensive drugs. * [[Electrolyte]]s ([[sodium]], [[potassium]]) * [[Glucose]] - to identify [[diabetes mellitus]] * [[Cholesterol]] Additional tests often include: * Testing of urine samples for [[proteinuria]] - again to pick up underlying kidney disease or evidence of hypertensive renal damage. * [[Electrocardiogram]] (EKG/ECG) - for evidence of the heart being under strain from working against a high blood pressure. Also may show resulting thickening of the heart muscle ([[left ventricular hypertrophy]]) or of the occurrence of previous silent cardiac disease (either subtle electrical conduction disruption or even a myocardial infarction). * [[Chest X-ray]] - again for signs of cardiac enlargement or evidence of [[Congestive heart failure|cardiac failure]]. == 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 Heart Study]] carried out in an American town: [[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. Recently ([[2004]]), the Framingham figures have been found to overestimate risks for the UK population considerably. The reasons are unclear. Nevertheless the Framingham work has been an important element of UK health policy. == Treatment == <!---need to be updated in accordance with the latest NICE guidelines (28th June 2006) ---> ===Lifestyle modification (nonpharmacologic treatment)=== * [[weight loss|Weight reduction]] and regular [[aerobic exercise]] (''e.g.'', [[jogging]]) are recommended as the first steps in treating mild to moderate hypertension. Regular mild exercise improves blood flow and helps to reduce resting heart rate and blood pressure. These steps are highly effective in reducing blood pressure, although drug therapy is still necessary for many patients with moderate or severe hypertension to bring their blood pressure down to a safe level. * Reducing [[sodium chloride|sodium (salt)]] [[Dieting|diet]] is proven very effective: it decreases blood pressure in about 60% of people (see above). Many people choose to use a [[salt substitute]] to reduce their salt intake. * Additional dietary changes beneficial to reducing blood pressure includes the [[DASH diet]] (Dietary Approaches to Stop Hypertension), which is rich in fruits and vegetables and low fat or fat-free dairy foods. This diet is shown effective based on National Institutes of Health sponsored research. In addition, an increase in daily calcium intake has the benefit of increasing dietary [[potassium]], which theoretically can offset the effect of sodium and act on the kidney to decrease blood pressure. This has also been shown to be highly effective in reducing blood pressure. * Discontinuing [[tobacco use]] and [[alcohol consumption]] has been shown to lower blood pressure. The exact mechanisms are not fully understood, but blood pressure (especially systolic) always transiently increases following alcohol and/or nicotine consumption. Besides, abstention from cigarette smoking is important for people with hypertension because it reduces the risk of many dangerous outcomes of hypertension, such as stroke and heart attack. Note that coffee drinking (caffeine ingestion) also increases blood pressure transiently, but does ''not'' produce chronic hypertension. * Relaxation therapy, such as [[meditation]], that reduces environmental stress, reducing [[Noise health effects|high sound levels]] and [[over-illumination]] can be an additional method of ameliorating hypertension. [[Jacobson's Progressive Muscle Relaxation]] and [[biofeedback]] are also used [http://www.mayoclinic.org/news2006-rst/3334.html] particularly device guided paced breathing [http://www.emaxhealth.com/106/5912.html] [http://www.medscape.com/viewarticle/539099]. ===Medications=== {{main|Antihypertensive}} Unless hypertension is severe, lifestyle changes such as those discussed in the preceding section are strongly recommended before initiation of drug therapy. Adoption of the DASH diet is one example of lifestyle change repeatedly shown to effectively lower mildly-elevated blood pressure. If hypertension is high enough to justify immediate use of medications, lifestyle changes are initiated concomitantly. There are many classes of medications for treating hypertension, together called [[antihypertensive]]s, which &mdash; by varying means &mdash; act by lowering blood pressure. Evidence suggests that reduction of the blood pressure by 5-6 mmHg can decrease the risk of stroke by 40%, of coronary heart disease by 15-20%, and reduces the likelihood of dementia, heart failure, and mortality from vascular disease. The aim of treatment should be blood pressure control to <140/90 mmHg for most patients, and lower in certain contexts such as diabetes or kidney disease (some medical professionals recommend keeping levels below 120/80 mmHg).[http://www.webmd.com/content/article/73/88927.htm] Each added drug may reduce the systolic blood pressure by 5-10 mmHg, so often multiple drugs are necessary to achieve blood pressure control. Commonly used drugs include: *[[ACE inhibitor]]s such as [[creatine]] [[captopril]], [[enalapril]], [[fosinopril]] (Monopril), [[lisinopril]] (Zestril), [[quinapril]], [[ramipril]] (Altace) *[[Angiotensin II receptor antagonist]]s: eg, [[telmisartan]] (Micardis, Pritor), [[irbesartan]] (Avapro), [[losartan]] (Cozaar), [[valsartan]] (Diovan), [[candesartan]] (Amias) *[[Alpha blocker]]s such as [[doxazosin]], [[prazosin]], or [[terazosin]] *[[Beta blocker]]s such as [[atenolol]], [[labetalol]], [[metoprolol]] (Lopressor, Toprol-XL), [[propranolol]]. *[[Calcium channel blocker]]s such as nifedipine (Adalat)<ref>[http://www.adalat.com/professionals-home/research/publications/ Kragten JA, Dunselman PHJM. Nifedipine gastrointestinal therapeutic system (GITS) in the treatment of coronary heart disease and hypertension. Expert Rev Cardiovasc Ther 5 (2007):643-653. FULL TEXT!] </ref> [[amlodipine]] (Norvasc), [[diltiazem]], [[verapamil]] *[[Direct renin inhibitor]]s such as [[aliskiren]] (Tekturna) *[[Diuretic]]s: eg, [[bendroflumethiazide]], [[chlortalidone]], [[hydrochlorothiazide]] (also called HCTZ) *Combination products (which usually contain HCTZ and one other drug) ====Choice of initial medication==== Unless the blood pressure is severely elevated, consensus guidelines call for medically-supervised lifestyle changes and observation before recommending initiation of drug therapy. All drug treatments have side effects, and while the evidence of benefit at higher blood pressures is overwhelming, drug trials to lower moderately-elevated blood pressure have failed to reduce overall death rates. If lifestyle changes are ineffective or the presenting blood pressure is critical, then drug therapy is initiated, often requiring more than one agent to effective lower hypertension. Which type of many medications should be used initially for hypertension has been the subject of several large studies and various national guidelines. The ALLHAT study showed better cost-effectiveness and slightly better outcomes for the [[thiazide]] diuretic [[chlortalidone]] compared with a [[calcium channel blocker]] and an [[ACE inhibitor]] in a 33,357-member ethnically mixed study group.<ref name="allhat">{{cite journal |url=http://jama.ama-assn.org/cgi/content/full/288/23/2981 |author=ALLHAT Officers and Coordinators for the ALLHAT Collaborative Research Group |journal=[[Journal of the American Medical Association|JAMA]] |title='''Major outcomes in high-risk hypertensive patients randomized to angiotensin-converting enzyme inhibitor or calcium channel blocker vs diuretic: The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)''' |year = 2002 |month = Dec 18 |volume = 288 |issue = 23 |pages = 2981–97 |pmid = 12479763 |doi=10.1001/jama.288.23.2981 }}</ref> The 1993 consensus recommendation for use of thiazide diuretics as initial treatment stems in part from the ALLHAT study results, which concluded in 2002 that "Thiazide-type diuretics are superior in preventing 1 or more major forms of CVD and are less expensive. They should be preferred for first-step antihypertensive therapy."<ref name="allhat"/> A subsequent smaller study (ANBP2) did not show the slight advantages in thiazide diuretic outcomes observed in the ALLHAT study, and actually showed slightly better outcomes for ACE-inhibitors in older white male patients.<ref name="anbp2">{{ cite journal |url=http://content.nejm.org/cgi/content/abstract/348/7/583 |author=Wing LM, Reid CM, Ryan P et al |journal=[[N Engl J Med|NEJM]] |title=A comparison of outcomes with angiotensin-converting--enzyme inhibitors and diuretics for hypertension in the elderly |year = 2003 |month = Feb 13 |volume = 348 |issue = 7 |pages = 583-92 |pmid = 12584366 }}</ref> [[Thiazide diuretics]] are effective, recommended as the best first-line drug for hypertension by many experts, and much more affordable than other therapies, yet they are not prescribed as often as some newer drugs. Arguably, this is partly because they are off-patent, less profitable, and thus rarely promoted by the drug industry.<ref name="promotion">{{cite journal |url=http://circ.ahajournals.org/cgi/content/full/99/15/2055 |author=Wang TJ, Ausiello JC, Stafford RS |journal=Circulation |title=Trends in Antihypertensive Drug Advertising, 1985–1996 |year = 1999 |volume = 99 |pages = 2055–2057 |pmid = 10209012 }}</ref> The consensus recommendations of [[thiazide diuretics]] as first-line therapy for hypertension stand against a the backdrop that all blood pressure treatments have side-effects. Potentially serious side effects of the [[thiazide diuretics]] include hypercholesterinemia, and [[impaired glucose tolerance]] with consequent increased risk of developing [[Diabetes mellitus type 2]]. The [[thiazide diuretics]] also deplete circulating potassium unless combined with a potassium-sparing diuretic or supplemental potassium. On this basis, the consensus recommendations to prefer use of thiazides as first line treatment for essential hypertension have been repeatedly and strongly questioned.<ref>{{cite journal | author = Lewis PJ, Kohner EM, Petrie A, Dollery CT | title = Deterioration of glucose tolerance in hypertensive patients on prolonged diuretic treatment | journal = Lancet | volume = 307 | issue = 7959 | pages = 564–566 | year = 1976 | pmid = 55840 | doi = 10.1016/S0140-6736(76)90359-7}} </ref><ref>{{cite journal | author = Murphy MB, Lewis PJ, Kohner E, Schumer B, Dollery CT | title = Glucose intolerance in hypertensive patients treated with diuretics; a fourteen-year follow-up | journal = Lancet | volume = 320 | issue = 8311 | pages = 1293–1295 | year = 1982 | pmid = 6128594 | doi = 10.1016/S0140-6736(82)91506-9}}</ref><ref>{{cite journal | author =Messerli FH, Williams B,Ritz E | title = Essential hypertension | journal = Lancet | volume = 370 | issue = 9587 | pages = 591–603| year = 2007| doi = 10.1016/S0140-6736(07)61299-9}}</ref> However as the Merck Manual of Geriatrics notes, "thiazide-type diuretics are especially safe and effective in the elderly."<ref>{{cite book |title=Merck Manual of Geriatrics |chapter=Section 11. Cardiovascular Disorders - Chapter 85. Hypertension |chapterurl=http://www.merck.com/mkgr/mmg/sec11/ch85/ch85a.jsp |date=July 2005}}</ref> == Cross-cultural approach == An effective cross-cultural approach is necesary to care for African-American patients with cardiovascular disease, especially hypertension. * http://www.c-comp.org Cultural Competence Online for Medical Practice (CCOMP) is a Clinician's Guide to Reduce Cardiovascular Disparities. See videos with real patient scenarios and case-based educational modules to increase awareness. Intended audience are medical students and physicians, patients may also benefit by reviewing these modules. ===Advice in the United Kingdom=== The risk of [[beta-blocker]]s provoking [[type 2 diabetes]] led to their downgrading to fourth-line therapy in the United Kingdom in June 2006<ref>{{cite web | author= Sheetal Ladva | title=NICE and BHS launch updated hypertension guideline | url=http://www.nelm.nhs.uk/Record%20Viewing/viewRecord.aspx?id=567178 | date=2006-06-28 | publisher=[[National Institute for Health and Clinical Excellence]] | accessdate=2006-09-30}}</ref>, in the revised national guidelines.<ref>{{cite web | title=Hypertension: management of hypertension in adults in primary care | url=http://www.nice.org.uk/download.aspx?o=CG034quickrefguide | format=PDF | publisher=[[National Institute for Health and Clinical Excellence]] | accessdate=2006-09-30}}</ref> ===Advice in the United States=== The ''Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure'' (JNC 7) in the United States recommends starting with a [[thiazide diuretic]] if single therapy is being initiated and another medication is not indicated.<ref name="jnc7" /> ===Chiropractic=== [[Chiropractic]] manipulation of the [[cervical]] spine in the neck is used by some as a treatment for hypertension,<ref name="pmid1573346">{{cite journal |author=Jamison JR, McEwen AP, Thomas SJ |title=Chiropractic adjustment in the management of visceral conditions: a critical appraisal |journal=J Manipulative Physiol Ther |volume=15 |issue=3 |pages=171–80 |year=1992 |pmid=1573346 |doi= |url=}}</ref><ref name="pmid8263434">{{cite journal |author=Plaugher G, Bachman TR |title=Chiropractic management of a hypertensive patient |journal=J Manipulative Physiol Ther |volume=16 |issue=8 |pages=544–9 |year=1993 |month=October |pmid=8263434 |doi= |url=}}</ref> as part of overall care and advice given by modern chiropracters.<ref name="pmid3517211">{{cite journal |author=Crawford JP, Hickson GS, Wiles MR |title=The management of hypertensive disease: a review of spinal manipulation and the efficacy of conservative therapeusis |journal=J Manipulative Physiol Ther |volume=9 |issue=1 |pages=27–32 |year=1986 |month=March |pmid=3517211 |doi= |url=}}</ref> Studies have shown mixed outcomes as to whether the technique works,<ref name="pmid8263434"/><ref name="pmid17252032">{{cite journal |author=Bakris G, Dickholtz M, Meyer PM, ''et al'' |title=Atlas vertebra realignment and achievement of arterial pressure goal in hypertensive patients: a pilot study |journal=J Hum Hypertens |volume=21 |issue=5 |pages=347–52 |year=2007 |month=May |pmid=17252032 |doi=10.1038/sj.jhh.1002133 |url=}}</ref> or not.<ref name="pmid12359986">{{cite journal |author=Goertz CH, Grimm RH, Svendsen K, Grandits G |title=Treatment of Hypertension with Alternative Therapies (THAT) Study: a randomized clinical trial |journal=J. Hypertens. |volume=20 |issue=10 |pages=2063–8 |year=2002 |month=October |pmid=12359986 |doi= |url=http://meta.wkhealth.com/pt/pt-core/template-journal/lwwgateway/media/landingpage.htm?issn=0263-6352&volume=20&issue=10&spage=2063}}</ref> One study found sustained improvement compared to brief massage, but similar to just resting for 5 minutes alone in a room.<ref name="pmid12021741">{{cite journal |author=Plaugher G, Long CR, Alcantara J, ''et al'' |title=Practice-based randomized controlled-comparison clinical trial of chiropractic adjustments and brief massage treatment at sites of subluxation in subjects with essential hypertension: pilot study |journal=J Manipulative Physiol Ther |volume=25 |issue=4 |pages=221–39 |year=2002 |month=May |pmid=12021741 |doi= |url=http://linkinghub.elsevier.com/retrieve/pii/S016147540228879X}}</ref> A more recent study showed a significant lowering of blood pressure in hypertensive patients after only one chiropractic adjustment of the atlas vertebra. The decrease in blood pressure was found immediately following the adjustment as well as a full eight weeks following the adjustment. Blood pressure in the group receiving chiropractic was lowered by an average of 17mmHg BP systolic and 10mmHg diastolic BP. <ref name=Bakrus>Bakris, G. (2007) Atlas vertebra realignment and achievement of arterial pressure goal in hypertensive patients: a pilot study. ''Journal of Human Hypertension 2007 (May);21 (5):347–352 [http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=17252032&query_hl=1&itool=pubmed_docsum available online]</ref> ===Systolic hypertension=== {{details|Systolic hypertension}} == See also == * [[Antihypertensive]] * [[Edible salt]] * [[Hypertensive emergency]] * [[Malignant hypertension]] * [[Exercise hypertension]] * [[White coat hypertension]] * [[Home blood pressure monitoring]] * [[Spontaneously hypertensive rat]] * [[Benign prostatic hyperplasia]] * [[Blood pressure]] * [[Prehypertension]] * [[Pulse pressure]] == References == <!-- --------------------------------------------------------------- See http://en.wikipedia.org/wiki/Wikipedia:Footnotes for a discussion of different citation methods and how to generate footnotes using the <ref> & </ref> ůtags and the {{Reflist}} template -------------------------------------------------------------------- --> {{Reflist|2}} <code><code><code><code><code></code></code></code></code></code> == External links == {{dmoz|/Health/Conditions_and_Diseases/Cardiovascular_Disorders/Vascular_Disorders/Hypertension/}} * [http://ww2.heartandstroke.ca/Page.asp?PageID=1975&ArticleID=5211 High Blood Pressure] from the Heart and Stroke Foundation of Canada * [http://medlineplus.nlm.nih.gov/medlineplus/highbloodpressure.html High Blood Pressure] from [[MedlinePlus]] * [http://www.nhlbi.nih.gov/hbp/ A guide to lowering high blood pressure] from the National Heart, Lung, and Blood Institute * [http://www.nhlbi.nih.gov/hbp/prevent/h_eating/h_eating.htm The DASH diet] from the National Heart, Lung, and Blood Institute * [http://www.americanheart.org/presenter.jhtml?identifier=2114 High Blood Pressure] (from the American Heart Association) * [http://kidney.niddk.nih.gov/kudiseases/pubs/hypertension/index.htm High Blood Pressure and Kidney Disease] from The National Kidney and Urologic Diseases Information Clearinghouse * [http://ukidney.com/mybp.html Blood pressure monitoring tool] Designed by a nephrologist from the University of Toronto * http://www.c-comp.org Cultural Competence Online for Medical Practice (CCOMP). A Clinician's Guide to Reduce Cardiovascular Disparities. Learn effective cross-cultural approaches to care for African-American patients with cardiovascular disease, especially hypertension. === Major studies === * [http://www.nhlbi.nih.gov/about/framingham/ The Framingham Heart Study] * [http://allhat.sph.uth.tmc.edu/default.htm#study Information on ALLHAT] {{Vascular diseases}} [[Category:Aging-associated diseases]] [[Category:Cardiology]] [[Category:Cardiovascular diseases]] [[Category:Medical conditions related to obesity]] [[Category:Nephrology]] [[Category:Blood pressure]] {{Link FA|ceb}} [[af:Hipertensie]] [[ar:فرط ضغط الدم]] [[zh-min-nan:Ko-hoeh-ap]] [[bs:Hipertenzija]] [[bg:Артериална хипертония]] [[ceb:Alta presyon]] [[cs:Hypertenze]] [[de:Arterielle Hypertonie]] [[et:Hüpertensioon]] [[es:Hipertensión arterial]] [[eo:Alta sangopremo]] [[eu:Hipertentsio]] [[fr:Hypertension artérielle]] [[ko:고혈압]] [[hr:Hipertenzija]] [[id:Tekanan darah tinggi]] [[it:Ipertensione arteriosa sistemica]] [[ku:Hîpertansiyon]] [[hu:Magas vérnyomás]] [[ms:Darah tinggi]] [[nl:Hypertensie]] [[ja:高血圧]] [[no:Hypertensjon]] [[pl:Nadciśnienie tętnicze]] [[pt:Hipertensão arterial]] [[qu:Llasaq yawar]] [[ru:Артериальная гипертензия]] [[sr:Хипертензија]] [[sv:Högt blodtryck]] [[th:โรคความดันโลหิตสูง]] [[tr:Yüksek tansiyon]] [[uk:Артеріальна гіпертензія]] [[zh:高血壓]]