Unlike high blood pressure, low blood pressure is defined primarily by signs and symptoms of low blood flow and not by a specific blood pressure number. Some individuals routinely may have blood pressure numbers of 90/50 with no symptoms and therefore do not have low blood pressure. However, others who normally have higher blood pressures may develop symptoms of low blood pressure if their blood pressure drops to 100/60.
Hypertension clinical guidelines from the American Heart Association are comprehensive guidelines for healthcare professionals for the detection and treatment of high blood pressure in a wide range of patients. Included in the 2018 hypertension clinical guidelines are proper methods for measuring blood pressure, risk factors for hypertension, and hypertension treatment for different populations.
How the heart pumps blood into the arteries with enough force to push blood to the far reaches of each organ from the top of the head to the bottom of the feet. Blood pressure can be defined as the pressure of blood on the walls of the arteries as it circulates through the body. Blood pressure is highest as its leaves the heart through the aorta and gradually decreases as it enters smaller and smaller blood vessels (arteries, arterioles, and capillaries). Blood returns in the veins leading to the heart, aided by gravity and muscle contraction.
Last year, new guidelines from the American Heart Association, the American College of Cardiology, and nine other health organizations lowered the numbers for the diagnosis of hypertension (high blood pressure) to 130/80 millimeters of mercury (mm Hg) and higher for all adults. The previous guidelines set the threshold at 140/90 mm Hg for people younger than age 65 and 150/80 mm Hg for those ages 65 and older.
Researchers at the University of Melbourne and Macquarie University have uncovered unusual activity between neurons controlling breathing and blood pressure during the development of essential hypertension. Essential hypertension, which is high blood pressure with no known cause, affects 30% of the global population and is a major contributor to cardiovascular disease.
Orthostasis literally means standing upright. Orthostatic hypotension, or postural hypotension, is defined as a decrease in systolic blood pressure of at least 20 mm Hg or at least 10mm Hg within 3 minutes of the patient standing. If orthostatic hypotension is present, the client may be at risk of falls and should be closely supervised with ambulation or advised to call for assistance with activity.

Methyldopa, formerly known under the brand name Aldomet, is one of the oldest blood pressure medications still in use. It was first introduced more than 50 years ago. Methyldopa works in the central nervous system to lower blood pressure. While its general use has declined over the years, methyldopa is considered the first-line of treatment for high blood pressure that develops during pregnancy.
Although it's most common in older adults, hypertension can also affect children. The normal blood pressure for a child is dependent upon the child's age, gender, and height. Your doctor can tell if your child's blood pressure is abnormal. Children are at higher risk for hypertension if they are overweight, African-American, or if they have a family history of the condition. Children with high blood pressure may benefit from the DASH diet and taking medications. Children with high blood pressure should also maintain a healthy weight and avoid tobacco smoke.
Hypertension defined as elevated blood pressure over several visits affects 1% to 5% of children and adolescents and is associated with long term risks of ill-health.[89] Blood pressure rises with age in childhood and, in children, hypertension is defined as an average systolic or diastolic blood pressure on three or more occasions equal or higher than the 95th percentile appropriate for the sex, age and height of the child. High blood pressure must be confirmed on repeated visits however before characterizing a child as having hypertension.[89] Prehypertension in children has been defined as average systolic or diastolic blood pressure that is greater than or equal to the 90th percentile, but less than the 95th percentile.[89] In adolescents, it has been proposed that hypertension and pre-hypertension are diagnosed and classified using the same criteria as in adults.[89]

Other causes of dehydration include exercise, sweating, fever, and heat exhaustion or heat stroke. Individuals with mild dehydration may experience only thirst and dry mouth. Moderate to severe dehydration may cause orthostatic hypotension (manifested by lightheadedness, dizziness, or fainting upon standing). Prolonged and severe dehydration can lead to shock, kidney failure, confusion, acidosis (too much acid in the blood), coma, and even death.
^ Jump up to: a b c Members, Authors/Task Force; Mancia, Giuseppe; Fagard, Robert; Narkiewicz, Krzysztof; Redon, Josep; Zanchetti, Alberto; Böhm, Michael; Christiaens, Thierry; Cifkova, Renata (13 June 2013). "2013 ESH/ESC Guidelines for the management of arterial hypertension". European Heart Journal. 34 (28): 2159–219. doi:10.1093/eurheartj/eht151. hdl:1854/LU-4127523. ISSN 0195-668X. PMID 23771844. Archived from the original on 27 January 2015.
About This Image: Person receiving a blood pressure test. Medical research shows that as we age blood pressure rises slightly to accommodate an increased demand of oxygen and nutrients. It is completely natural for the first number (systolic) to be 100 plus our age. A recent study by a group of UCLA researchers came very close to corroborating Dr. Piette's guide for blood pressure of 100 plus your age for men, subtracting 10 for women, and this is after this rule had been in use for five or more decades. Are we now being taught that Dr. Piette's guide for blood pressure is wrong merely for drug company profit?

The brain requires unobstructed blood flow to nourish its many functions. Very high, sustained blood pressure will eventually cause blood vessels to weaken. Over time these weaken vessels can break, and blood will leak into the brain. The area of the brain that is being fed by these broken vessels start to die, and this will cause a stroke. Additionally, if a blot clot blocks a narrowed artery, blood ceases to flow and a stroke will occur.
High blood pressure is more common in older people. At age 45, more men have hypertension than women. By age 65, this is reversed and more women are affected. People with diabetes have a greater risk of hypertension than those without diabetes. Having a close family member with high blood pressure also increases your risk of developing it. About 60% of all people with diabetes also have hypertension.
Some high blood pressure medications can, in fact, lead to weight gain. Common offenders include older beta blockers such as propranolol (Inderal) and atenolol (Tenormin). There could be several reasons for this -- including the fact that the medications can make patients feel tired and thus less likely to exercise. Minoxidil tablets (Loniten) -- used only when other antihypertensive medications have failed -- can also cause weight gain. Weight gain is also listed as a common side effect of doxazosin (Cardura). Diuretics are more likely to cause weight loss.
Blood pressure refers to the force exerted by circulating blood on the walls of blood vessels and constitutes one of the principal vital signs. The pressure of the circulating blood decreases as blood moves through arteries, arterioles, capillaries, and veins; the term blood pressure generally refers to arterial pressure, i.e., the pressure in the larger arteries, arteries being the blood vessels which take blood away from the heart.
1. Concentrate on foods that lower blood pressure. Sugary, processed foods contain salt, sugar, damaged fats, and food sensitivities like gluten that contribute to or exacerbate high blood pressure. Shifting to a whole, unprocessed foods diet can dramatically impact your blood pressure. Many whole, unprocessed foods are rich in potassium, a mineral that supports healthy blood pressure. Some research shows that too much sodium and low amounts of potassium – can contribute to high blood pressure. Research shows people with high blood pressure can benefit from increased potassium in foods including avocado, spinach, wild-caught salmon, and sweet potatoes.
2. Take the right nutrients. Talk with your chiropractor or other healthcare professional about the wide range of well-studied nutrients that, along with dietary and lifestyle modifications, can help normalize your blood pressure. One meta-analysis found magnesium supplements could lower blood pressure. Likewise, researchers find a small but significant decline in blood pressure for people with hypertension who use fish oil. (You can get all of fish oil’s benefits combined with anti-inflammatory flax oil and GLA in our Optimal Omega.) 
Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol. 2017; pii: S0735-1097(17)41519-1. PMID: 29146535 www.ncbi.nlm.nih.gov/pubmed/29146535. 

It is important to go to your regular check-ups with your doctor. Hypertension is a common condition and, if caught, can be treated with medication to prevent complications. However, if you experience any of the symptoms of hypertension, such as frequent headaches, recurrent dizziness, nosebleeds, shortness of breath, nausea or vomiting, don't wait—speak to your doctor immediately.

My BP gets taken once, when I arrive. Occasionally the top number is over 120. No health care provider has ever said anything to me about it. Only ONCE in the past 5 years, has any health care provider or assistant taken my BP again during the course of the exam to see if there’s been a change. So by your defintion, I’m getting poor clinical care. And that means what? As in, what will make that change? It sure won’t change for me raising the issue, I’m lucky if the provider even speaks to me. Providers spend more time staring at monitors then looking directly at the client/patient in the examination room.


Secondary hypertension results from an identifiable cause. Kidney disease is the most common secondary cause of hypertension.[23] Hypertension can also be caused by endocrine conditions, such as Cushing's syndrome, hyperthyroidism, hypothyroidism, acromegaly, Conn's syndrome or hyperaldosteronism, renal artery stenosis (from atherosclerosis or fibromuscular dysplasia), hyperparathyroidism, and pheochromocytoma.[23][47] Other causes of secondary hypertension include obesity, sleep apnea, pregnancy, coarctation of the aorta, excessive eating of liquorice, excessive drinking of alcohol, and certain prescription medicines, herbal remedies, and illegal drugs such as cocaine and methamphetamine.[23][48] Arsenic exposure through drinking water has been shown to correlate with elevated blood pressure.[49][50]
The most widely used classification of blood pressure readings currently is given in the table below. Stratification of the blood pressure readings into different categories is important because of increasing severity of high blood pressure readings and different approach to the treatment of these conditions. Another table below the first one gives the blood pressure chart with different categories of the blood pressure, symptoms and the treatment.
^ Nagele, Eva; Jeitler, Klaus; Horvath, Karl; Semlitsch, Thomas; Posch, Nicole; Herrmann, Kirsten H.; Grouven, Ulrich; Hermanns, Tatjana; Hemkens, Lars G.; Siebenhofer, Andrea (2014). "Clinical effectiveness of stress-reduction techniques in patients with hypertension". Journal of Hypertension. 32 (10): 1936–44. doi:10.1097/HJH.0000000000000298. ISSN 0263-6352. PMID 25084308.
Some people may ask why doctors are lowering the threshold for high blood pressure, when it was already difficult for many patients to achieve the previous blood pressure targets of below 140 mm Hg/90 mm Hg, said Dr. Pamela B. Morris, a preventive cardiologist and chairwoman of the ACC's Prevention of Cardiovascular Disease Leadership Council. However, Morris said that the guidelines were changed because "we now have more precise estimates of the risk of [high] blood pressures," and these new guidelines really communicate that risk to patients. So, just because it's going to be difficult for people to achieve, "I don't think it's a reason not to communicate the risk to patients, and to empower them to make appropriate lifestyle modifications," Morris told Live Science.
The cuff is placed around the upper arm and inflated with an air pump to a pressure that blocks the flow of blood in the main artery that travels through the arm. The arm is held at the side of the body at the level of the heart, and the pressure of the cuff is gradually released. As the pressure decreases, a health practitioner listens with a stethoscope over the artery at the front of the elbow or an electronic machine senses the pulsation. The pressure at which the practitioner (or machine) first hears a pulsation from the artery is the systolic pressure (the top number). As the cuff pressure decreases further, the pressure at which the pulsation finally stops is the diastolic pressure (the bottom number).
Optimal blood pressure is less than 120/80 (systolic/diastolic). In healthy people, low blood pressure without any symptoms is not usually a concern and does not need to be treated. But low blood pressure can be a sign of an underlying problem -- especially in the elderly -- where it may cause inadequate blood flow to the heart, brain, and other vital organs.
Because of the need for emergency care, it is important to recognize the early signs of malignant hypertension. The first giveaway is blood pressure of 180/120. You might have bleeding in the eyes due to rupture of the small blood vessels. Other malignant hypertension symptoms can include chest pain, dizziness, a headache, numbness in your extremities, and confusion.

High blood pressure is classified as either primary (essential) high blood pressure or secondary high blood pressure.[5] About 90–95% of cases are primary, defined as high blood pressure due to nonspecific lifestyle and genetic factors.[5][6] Lifestyle factors that increase the risk include excess salt in the diet, excess body weight, smoking, and alcohol use.[1][5] The remaining 5–10% of cases are categorized as secondary high blood pressure, defined as high blood pressure due to an identifiable cause, such as chronic kidney disease, narrowing of the kidney arteries, an endocrine disorder, or the use of birth control pills.[5]


Blood pressure fluctuates throughout the day, so measuring it in the morning might yield a different number than, say, the afternoon. Conditions like stress and lack of sleep can also fluctuate blood pressure. Visiting your doctor might feel nerve-wracking, which can elevate your blood pressure and create a condition called white coat hypertension.
In most people with established essential hypertension, increased resistance to blood flow (total peripheral resistance) accounts for the high pressure while cardiac output remains normal.[52] There is evidence that some younger people with prehypertension or 'borderline hypertension' have high cardiac output, an elevated heart rate and normal peripheral resistance, termed hyperkinetic borderline hypertension.[53] These individuals develop the typical features of established essential hypertension in later life as their cardiac output falls and peripheral resistance rises with age.[53] Whether this pattern is typical of all people who ultimately develop hypertension is disputed.[54] The increased peripheral resistance in established hypertension is mainly attributable to structural narrowing of small arteries and arterioles,[55] although a reduction in the number or density of capillaries may also contribute.[56]
^ Jump up to: a b c d e f James, PA.; Oparil, S.; Carter, BL.; Cushman, WC.; Dennison-Himmelfarb, C.; Handler, J.; Lackland, DT.; Lefevre, ML.; et al. (Dec 2013). "2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults: Report From the Panel Members Appointed to the Eighth Joint National Committee (JNC 8)". JAMA. 311 (5): 507–20. doi:10.1001/jama.2013.284427. PMID 24352797.
The portal venous system contains veins coming from the stomach, intestine, spleen, and pancreas. These veins merge into the portal vein, which branches into smaller vessels and travel through the liver. Portal hypertension occurs when there is an increase in the blood pressure within the portal venous system. When the vessels in the liver are blocked due to liver damage, blood cannot flow properly through the liver. This causes high blood pressure in the portal system.

Low blood pressure is also known as hypotension. This is usually defined in an adult as a systolic recording of less than 90 mmHg, although it has been suggested that for elderly people, below 110 mmHg is a more appropriate definition. Blood pressure and heart rate are controlled by the autonomic nervous system (the nervous system that controls bodily functions that we do not have to think about).                                                                                                                                                                                                


An abnormally fast heart rate (tachycardia) also can cause low blood pressure. The most common example of tachycardia causing low blood pressure is atrial fibrillation (Afib). Atrial fibrillation is a disorder of the heart characterized by rapid and irregular electrical discharges from the muscle of the heart causing the ventricles to contract irregularly and (usually) rapidly. The rapidly contracting ventricles do not have enough time to fill maximally with blood before each contraction, and the amount of blood that is pumped decreases in spite of the faster heart rate. Other abnormally rapid heart rhythms such as ventricular tachycardia also can produce low blood pressure, and sometimes life-threatening shock.
It is important to recognise that low blood pressure can cause no symptoms at all, and is a common normal finding in young people and athletes. However, in some people, low blood pressure causes symptoms which can significantly interfere with their quality of life. These can include syncope (fainting), pre-syncope (near fainting, usually associated with feeling light-headed), sweating, tiredness, slow thinking (brain fog), nausea, visual blurring, hearing disturbances, headache, palpitations, neck pain, breathlessness and chest pain.
If your systolic and diastolic blood pressure are in two different categories, doctors consider the number that is in the higher category. For example, if your blood pressure is 135/91, your systolic blood pressure is in the prehypertensive range and your diastolic blood pressure is in the range of Stage 1 hypertension. Your measurement or 135/91 would place you in the category of Stage 1 hypertension.
Stage 1 and Stage 2 hypertensions require therapy with anti-hypertensive drugs to bring down the blood pressure. Lifestyle modifications are also necessary, but often it is not sufficient for satisfactory control of blood pressure. Hypertension is often asymptomatic in the early course of disease. Symptoms like headache, lightheadedness, palpitations and easy fatigability may occur and chances of them being present increases with increasing blood pressure. 

A blood pressure reading measures both the systolic and diastolic forces, with the systolic pressure listed first. The numbers show your pressure in units of millimeters of mercury (mm Hg)—how high the pressure inside your arteries would be able to raise a column of mercury. For example, a reading of 120/80 mm Hg means a systolic pressure of 120 mm Hg and diastolic pressure of 80 mm Hg.
How the heart pumps blood into the arteries with enough force to push blood to the far reaches of each organ from the top of the head to the bottom of the feet. Blood pressure can be defined as the pressure of blood on the walls of the arteries as it circulates through the body. Blood pressure is highest as its leaves the heart through the aorta and gradually decreases as it enters smaller and smaller blood vessels (arteries, arterioles, and capillaries). Blood returns in the veins leading to the heart, aided by gravity and muscle contraction.
The guidelines also say that a patient's blood pressure levels should be based on an average of two to three readings on at least two different occasions. It's also reasonable for doctors to screen for "white-coat hypertension," which occurs when blood pressure is elevated in a medical setting but not in everyday life, the authors said. This can be done by having patients measure their blood pressure at home. 

The authors bring several evidence-based yet progressive concepts into the guidelines, the first of which is that high blood pressure should be treated using a team approach. This makes sense, as science supports more and better patient education around self-monitoring, nutrition, and lifestyle changes, as well as stress management. Telehealth is emphasized as a cost-effective method of ongoing monitoring that is more convenient for patients than frequent office visits.
^ Qaseem A, Wilt TJ, Rich R, Humphrey LL, Frost J, Forciea MA (17 January 2017). "Pharmacologic Treatment of Hypertension in Adults Aged 60 Years or Older to Higher Versus Lower Blood Pressure Targets: A Clinical Practice Guideline From the American College of Physicians and the American Academy of Family Physicians". Annals of Internal Medicine. 166 (6): 430–437. doi:10.7326/M16-1785. PMID 28135725.

Much of the disease burden of high blood pressure is experienced by people who are not labeled as hypertensive.[87] Consequently, population strategies are required to reduce the consequences of high blood pressure and reduce the need for antihypertensive medications. Lifestyle changes are recommended to lower blood pressure, before starting medications. The 2004 British Hypertension Society guidelines[87] proposed lifestyle changes consistent with those outlined by the US National High BP Education Program in 2002[95] for the primary prevention of hypertension:
Heart attack. Signs of heart attack include mild or severe chest pain or discomfort in the center of the chest or upper abdomen that lasts for more than a few minutes or goes away and comes back. It can feel like pressure, squeezing, fullness, heartburn, or indigestion. There may also be pain down the left arm. Women may also have chest pain and pain down the left arm, but they are more likely to have less typical symptoms, such as shortness of breath, nausea, vomiting, unusual tiredness, and pain in the back, shoulders, or jaw. Read more about the signs and symptoms of a heart attack.
^ Aronow WS, Fleg JL, Pepine CJ, Artinian NT, Bakris G, Brown AS, Ferdinand KC, Ann Forciea M, Frishman WH, Jaigobin C, Kostis JB, Mancia G, Oparil S, Ortiz E, Reisin E, Rich MW, Schocken DD, Weber MA, Wesley DJ, Harrington RA, Bates ER, Bhatt DL, Bridges CR, Eisenberg MJ, Ferrari VA, Fisher JD, Gardner TJ, Gentile F, Gilson MF, Hlatky MA, Jacobs AK, Kaul S, Moliterno DJ, Mukherjee D, Rosenson RS, Stein JH, Weitz HH, Wesley DJ (2011). "ACCF/AHA 2011 expert consensus document on hypertension in the elderly: a report of the American College of Cardiology Foundation Task Force on Clinical Expert Consensus Documents developed in collaboration with the American Academy of Neurology, American Geriatrics Society, American Society for Preventive Cardiology, American Society of Hypertension, American Society of Nephrology, Association of Black Cardiologists, and European Society of Hypertension". J Am Soc Hypertens. 5 (4): 259–352. doi:10.1016/j.jash.2011.06.001. PMID 21771565.
Events in early life, such as low birth weight, maternal smoking, and lack of breastfeeding may be risk factors for adult essential hypertension, although the mechanisms linking these exposures to adult hypertension remain unclear.[43] An increased rate of high blood urea has been found in untreated people with hypertension in comparison with people with normal blood pressure, although it is uncertain whether the former plays a causal role or is subsidiary to poor kidney function.[44] Average blood pressure may be higher in the winter than in the summer.[45] Periodontal disease is also associated with high blood pressure.[46]
Enlarged heart. High blood pressure increases the amount of work for your heart. Like any heavily exercised muscle in your body, your heart grows bigger (enlarges) to handle the extra workload. The bigger your heart is, the more it demands oxygen-rich blood but the less able it is to maintain proper blood flow. As a result, you feel weak and tired and are not able to exercise or perform physical activities. Without treatment, your heart failure will only get worse.
Researchers at the University of Melbourne and Macquarie University have uncovered unusual activity between neurons controlling breathing and blood pressure during the development of essential hypertension. Essential hypertension, which is high blood pressure with no known cause, affects 30% of the global population and is a major contributor to cardiovascular disease.

Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated.[10] High blood pressure typically does not cause symptoms.[1] Long-term high blood pressure, however, is a major risk factor for coronary artery disease, stroke, heart failure, atrial fibrillation, peripheral vascular disease, vision loss, chronic kidney disease, and dementia.[2][3][4][11]


Beta-blockers cause the heart to slow down and so some of their side effects can be traced to that mechanism of action. Dizziness, weakness, fatigue, and fainting are possible. Beta-blockers also affect the respiratory system, so other side effects include shortness of breath, difficulty breathing, and chest pain. Beta-blockers should not be withdrawn suddenly, as that could result in a heart attack or sudden death.
A person consistently showing blood pressure higher than 140/90 over several readings is considered to have hypertension. Doctors advise these people to make effective lifestyle changes to help lower their blood pressure, such as maintaining a healthy weight, including exercise in their daily routine, limiting salt and alcohol intake, and quitting smoking. The doctors will also recommend medication for hypertension depending on how much higher the BP is as compared to the normal blood pressure range and any other health problems that the patient faces.

^ Qaseem A, Wilt TJ, Rich R, Humphrey LL, Frost J, Forciea MA (17 January 2017). "Pharmacologic Treatment of Hypertension in Adults Aged 60 Years or Older to Higher Versus Lower Blood Pressure Targets: A Clinical Practice Guideline From the American College of Physicians and the American Academy of Family Physicians". Annals of Internal Medicine. 166 (6): 430–437. doi:10.7326/M16-1785. PMID 28135725.

A number of medications contribute to heart disease, including corticosteroids, oral contraceptives, some decongestants, medications that contain caffeine, and many others. In general, it is best to check the label to see if hypertension is one of the side effects of any medications you take, especially if you already have hypertension or if you are at increased risk for it.
Mountains of research over time have shown a very clear link between high blood pressure and cardiovascular disease. A 20-point higher systolic blood pressure or a 10-point higher diastolic blood pressure is associated with double your risk of death from a heart attack, stroke, or other cardiovascular complication (like abdominal aortic aneurysm or heart failure). What many people don’t realize is that those who survive these events find their lives permanently altered by disability and medical complications.
Postural hypotension occurs most frequently in people who are taking drugs to control high blood pressure (hypertension). It can also be related to pregnancy, strong emotions, hardening of the arteries (atherosclerosis), or diabetes. The elderly are particularly affected, especially those who have high blood pressure or autonomic nervous system dysfunction.
Hypertension is actually of two types, one is called Primary Hypertension or Essential Hypertension, and this type of hypertension develops gradually over the years as a person ages, and it has no known causes. The other type of hypertension is called Secondary Hypertension, and this type is caused by different diseases, and a person’s lifestyle factors, like diet, sedentary lifestyle, alcohol intake etc.
“While we always knew this could result in a falsely elevated measurement, it is now officially poor clinical technique resulting in an invalid reading.” So what? Does that mean that someone’s actually going to visit clinics all over the US to make sure that BPs are taken several times during the visit? Is that going to be added to the skin inspections (that aren’t done by the health care providers I have access to) done at every “wellness” exam? And the questions regarding mental health/depression that aren’t asked that are “now required”?
Normal blood pressure is below 120/80. New guidelines from the American Heart Association (AHA) and the American College of Cardiology (ACC) published in November of 2017 consider blood pressure elevated between 120/80 and 129/80. High blood pressure or hypertension is now classified as stage 1 if your systolic reading falls between 130 and 139 or your diastolic reading is between 80 and 89. A measure of 140/90 or higher is now considered stage 2 hypertension. A hypertensive crisis is defined as a systolic rate over 180 or a diastolic rate above 120. An elevated blood pressure means that the heart must work harder to pump blood. High blood pressure can also damage the walls of the arteries. Over time, hypertension increases the risk of heart disease, kidney disease, and stroke. It is estimated that one in three adults in America are affected by hypertension.
High blood pressure is classified as either primary (essential) high blood pressure or secondary high blood pressure.[5] About 90–95% of cases are primary, defined as high blood pressure due to nonspecific lifestyle and genetic factors.[5][6] Lifestyle factors that increase the risk include excess salt in the diet, excess body weight, smoking, and alcohol use.[1][5] The remaining 5–10% of cases are categorized as secondary high blood pressure, defined as high blood pressure due to an identifiable cause, such as chronic kidney disease, narrowing of the kidney arteries, an endocrine disorder, or the use of birth control pills.[5] 

As of 2014, approximately one billion adults or ~22% of the population of the world have hypertension.[137] It is slightly more frequent in men,[137] in those of low socioeconomic status,[6] and it becomes more common with age.[6] It is common in high, medium, and low income countries.[137][138] In 2004 rates of high blood pressure were highest in Africa, (30% for both sexes) and lowest in the Americas (18% for both sexes). Rates also vary markedly within regions with rates as low as 3.4% (men) and 6.8% (women) in rural India and as high as 68.9% (men) and 72.5% (women) in Poland.[139] Rates in Africa were about 45% in 2016.[140]
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Health care providers measure blood pressure with a sphygmomanometer (sfig-mo-muh-NAH-muh-ter), which has a cuff that's wrapped around the upper arm and pumped up to create pressure. When the cuff is inflated, it squeezes a large artery in the arm, stopping the blood flow for a moment. Blood pressure is measured as air is gradually let out of the cuff, which allows blood to flow through the artery again. 

^ Martin-Cabezas, Rodrigo; Seelam, Narendra; Petit, Catherine; Agossa, Kévimy; Gaertner, Sébastien; Tenenbaum, Henri; Davideau, Jean-Luc; Huck, Olivier (October 2016). "Association between periodontitis and arterial hypertension: A systematic review and meta-analysis". American Heart Journal. 180: 98–112. doi:10.1016/j.ahj.2016.07.018. ISSN 1097-6744. PMID 27659888.
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