Hypertension (patient information)

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 * Associate Editor-in-Chief: Atif Mohammad, MD

Overview
Hypertension, commonly referred to as "high blood pressure" or HTN, is a medical condition in which the blood pressure is chronically elevated. While it is formally called arterial hypertension, the word "hypertension" without a qualifier usually refers to arterial hypertension. Blood pressure is the force of your blood pushing against the walls of your arteries. Each time your heart beats, it pumps out blood into the arteries. Your blood pressure is highest when your heart beats, pumping the blood. This is called systolic pressure. When your heart is at rest, between beats, your blood pressure falls. This is the diastolic pressure.

Hypertension or high blood pressure is considered to be present when a person's systolic blood pressure is consistently 140 mmHg or greater, and/or their diastolic blood pressure is consistently 90 mmHg or greater. Recently, as of 2003, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure 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 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 kidney disease studies have shown that blood pressure over 130/80 mmHg should be considered high and warrants further treatment. Even lower numbers are considered diagnostic using home blood pressure monitoring devices.

What are the symptoms of Hypertension?
Most of the time, there are no symptoms. For most patients, high blood pressure is found when they visit their health care provider or have it checked elsewhere.

Because there are no symptoms, people can develop heart disease and kidney problems without knowing they have high blood pressure.

If you have a severe headache, nausea or vomiting, confusion, changes in your vision, or nosebleeds you may have a severe and dangerous form of high blood pressure called [[malignant hypertension (patient information)|malignant hypertension]

What causes Hypertension?
Hypertension is generally sub divided into 2 types:


 * 1) Essential Hypertension
 * 2) Secondary Hypertension

Essential Hypertension
Essential hypertension is the most prevalent hypertension type, affecting 90-95% of hypertensive patients.Although there is no direct cause or mechanism identified some factors are considered to cause Essential Hypertension.
 * Sedentary Lifestyle
 * Obesity accounts for 80-85% of essential hypertension
 * Increased salt intake
 * Increased youalcohol intake
 * Vitamin D Deficiency
 * Family history of high blood pressure
 * Genetic diseases
 * Renin -a hormone produced by the kidneys is thought to activate sympathetic system which functions to control most of body' internal organs under different conditions.
 * High fructose(sugar)corn syrup
 * Metabolic syndrome-in which body develops insulin resistance due to obesity and has high blood pressure, sugar,cholesterol and increased waist circumference.

Secondary hypertension
Secondary hypertension by definition results from an identifiable cause. This type is important to recognize since it's treated differently than essential hypertension, by treating the underlying cause of the elevated blood pressure. Hypertension results compromise or imbalance of the pathophysiological mechanisms, such as the hormone-regulating endocrine system, that regulate blood plasma volume and heart function. Many conditions cause hypertension, some are common and well recognized secondary causes such as
 * Renovascular Hypertension: Due to fibromuscular dysplasia and renal artery stenosis. In both conditiions, increased blood pressure occurs due to narrowing of arteries supplying to the kidney.
 * Pheochromocytoma: Caused by an excessive secretion of norepinephrine and epinephrine which promotes vasoconstriction
 * Hyperaldosteronism (Conn's syndrome): Idiopathic hyperaldosteronism, Liddle's syndrome (also called pseudoaldosteronism), glucocorticoid remediable aldosteronism
 * Cushing's syndrome - an excessive secretion of glucocorticoids causes the hypertension
 * Hyperparathyroidism
 * Acromegaly
 * Hyperthyroidism
 * Hypothyroidism
 * Chronic Kidney disease
 * Coarctation of Aorta
 * Drugs: Oral Contraceptives, steroids, NSAIDs, nasal decongestants with adrenergic effects, MAOIs, adrenoceptor stimulants.
 * Scleroderma
 * Neurofibromatosis
 * Pregnancy-unclear mechanism
 * Obstructive sleep apnea
 * Fever: unclear etiology
 * Liquorice
 * White coat hypertension: that is, elevated blood pressure in a clinical setting but not in other settings, probably due to the anxiety some people experience during a clinic visit.
 * Perioperative hypertension is development of hypertension just before, during or after surgery. It may occur before surgery during the induction of anesthesia; intraoperatively e.g. by pain-induced sympathetic nervous system stimulation; in the early postanesthesia period, e.g. by pain-induced sympathetic stimulation, hypothermia, hypoxia, or hypervolemia from excessive intraoperative fluid therapy; and in the 24 to 48 hours after the postoperativ period as fluid is mobilized from the extravascular space. In addition, hypertension may develop perioperatively because of discontinuation of long-term antihypertensive medication.

Who is at highest risk?
Essential hypertension which is the more common form has several risk factors.Of most importance are


 * Increased salt intake in diet
 * Obesity
 * Smoking
 * Increased alcohol intake
 * Family history where parents are hypertensive
 * High cholesterol diet
 * Certain personality traits like in general people who are more commmonly impatient,suffer from high anxiety state and have hostile attitudes.

There is a debate over Hypertension to be more common among black population as compared to whites.It is seen to be more common though exact though there is no exactt reason or mechanism for it.Currently, healthcare professionals identify it to be more common due to


 * Increased salt intake and cholesterol diet
 * Lower socioeconomic status/stress

When to seek urgent medical care?
There is no specific rule of thumb.But,one should have have blood pressure every 2 years by the primary care doctor if it is below 120/80 and yearly if blood pressure ranges from 120-139/80-89 according to the 2007 United States Preventive Services Task Force (USPSTF)guidelines.

In the setting of blood pressure >120/80 with severe headaches,vision difficulty,dizziness,loss of consciousness,chest pain,leg and arm weakness,nausea,vomiting and fatigue one should seek for urgent medical care .Hypertension is generally associated with a wide variety of symptoms but generally causes problems to the heart,brain,eyes/vision,kidneys,nerves and arm/leg weakness.

Diagnosis
Your health care provider will check your blood pressure several times before diagnosing you with high blood pressure. It is normal for your blood pressure to be different depending on the time of day.

Blood pressure readings taken at home may be a better measure of your current blood pressure than those taken at your doctor's office. Make sure you get a good quality, well-fitting home device. It should have the proper sized cuff and a digital readout.

Practice with your health care provider or nurse to make sure you are taking your blood pressure correctly. Your doctor will perform a physical exam to look for signs of heart disease, damage to the eyes, and other changes in your body.

Treatment options
Hypertension is a disease which can always be controlled.But it cannot be completely cured.What that means is that ,like Type 2 Diabetes your blood pressure measurements can be controlled and remain within certain limits but it does not exclude the chance one will never have high blood pressure all his life.

Hypertension can be controlled by
 * 1) Lifestyle preventive measures
 * 2) Medications

Lifestyle Preventive Measures
Several guidelines have been recommended by the American Heart Association, National Heart, Lung, and Blood Institute, American Academy of Family Physicians and Mayo Clinic regarding lifestyle to improve one's blood pressure or prevent from being hypertensive.Following measures should be kept in mind:
 * Have blood pressure checked frequently by your doctor.Although several devices are available, but it is better to get it checked by a health care professional
 * Maintain a diet with as low salt as possible.Avoid fats in diet and try to avoid fried food especially fast food while dinning out.
 * Increased content of fruits and vegetables in diet
 * Exercise regularly but according to your doctor's recommendations
 * High cholesterol diet should be avoided.
 * Drink moderate amounts of coffee or tea.Excessive amounts can lead to high blood pressures
 * Have more fiber in diet
 * Limit alcohol intake

Medications
Following are the medications given for High blood pressure:


 * Diuretics: These are the water pills which function to decrease salt content inside the body
 * Beta Blockers: These are known to lower the heart rate along with blood pressure.
 * ACE inhibitors: These decrease a hormone Angiotensin which acts on the same pathway as Renin does to increase the blood pressure.
 * Calcium Channel Blockers: These prevent Calcium from entering the arteries of the heart and prevent their narrowing thus lowering blood pressures.
 * Angiotensin II blockers: These directly act to decrease Angiotensin levels in the body
 * Alpha Blockers: These also act to decrease the narrowing of arteries to lower blood pressure.
 * Combined Alpha/Beta Blckers-These act in a similar manner as Alpha and Beta blockers to lower blood pressure.
 * Centrally Acting Anti-hypertensives-These act through the brain to decrease blood pressure
 * Directly acting Vasodilators-These are used in special conditions like pregnancy and directly act to prevent narrowing of arteries which can lead to high blood pressures.

Where to find medical care for Hypertension?
Directions to Hospitals Treating Hypertension

What to expect (Outlook/Prognosis)?
Hypertension cannot be completely cured .It can be well controlled under the normal limits if one tries to follow lifestyle preventive measures like exercising, eating a heart healthy diet, avoiding the different risk factors like high cholesterol salty diet, smoking alcohol intake,stress.Besides that medications are given as mentioned above.But if not well-controlled it can lead to various complications as are described below.So it is always important to maintain a healthy diet and active lifestyle.<refhttp://www.americanheart.org/

Possible complications
Hypertension can lead to several complications which are related to organ damage. It causes-
 * Heart:Myocardial Infarction (Heart attack),Cardiomyopathy (Heart failure)
 * Brain-Cerebrovascular accident (Stroke),Encephalopathy(confusion,convulsion,headaces), Subrachnoid Haemorrhage (a type of brain haemorrhage-svere headace,nausea,vomiting,increased light sensitivity and loss of consciousness)
 * Eyes-Retinaopathy (blurred vision which can in extreme conditiions lead to blindness)
 * Kdney-Nephropathy,Renal Failure(damage to kidneys lead to excessive urination at night,blood in urine,foamy urine due to abnormal protein loss in urine,abnormal levels of sodium,calcium and potassium )