Obesity: As body weight increases, the blood pressure rises. Obesity is defined as having a body mass index (BMI) greater than 30 kg/m. A BMI of 25-30 kg/m is considered overweight (BMI=weight in pounds x 703/ height in inches). Being overweight increases the risk of high blood pressure. Healthcare professionals recommend that all individuals who are obese and have high blood pressure lose weight until they are within 15% of their healthy body weight.

Hypertension results from a complex interaction of genes and environmental factors. Numerous common genetic variants with small effects on blood pressure have been identified[34] as well as some rare genetic variants with large effects on blood pressure.[35] Also, genome-wide association studies (GWAS) have identified 35 genetic loci related to blood pressure; 12 of these genetic loci influencing blood pressure were newly found.[36] Sentinel SNP for each new genetic locus identified has shown an association with DNA methylation at multiple nearby CpG sites. These sentinel SNP are located within genes related to vascular smooth muscle and renal function. DNA methylation might affect in some way linking common genetic variation to multiple phenotypes even though mechanisms underlying these associations are not understood. Single variant test performed in this study for the 35 sentinel SNP (known and new) showed that genetic variants singly or in aggregate contribute to risk of clinical phenotypes related to high blood pressure.[36]


Changes in blood vessel structure. Blood vessels have layers of the proteins elastin and collagen. Elastin is what makes blood vessels flexible. Collagen, which is stiffer, gives vessels structure. With age, elastin breaks down. Even the elastin that remains becomes less elastic. Meanwhile, collagen deposits in the vessels increase. As a result, blood vessels grow thicker and bend less easily over time. These changes may lead to higher systolic blood pressure.

Many mechanisms have been proposed to account for the rise in peripheral resistance in hypertension. Most evidence implicates either disturbances in the kidneys' salt and water handling (particularly abnormalities in the intrarenal renin–angiotensin system)[61] or abnormalities of the sympathetic nervous system.[62] These mechanisms are not mutually exclusive and it is likely that both contribute to some extent in most cases of essential hypertension. It has also been suggested that endothelial dysfunction and vascular inflammation may also contribute to increased peripheral resistance and vascular damage in hypertension.[63][64] Interleukin 17 has garnered interest for its role in increasing the production of several other immune system chemical signals thought to be involved in hypertension such as tumor necrosis factor alpha, interleukin 1, interleukin 6, and interleukin 8.[65]
Low blood pressure is diagnosed by a doctor when they check your blood pressure with a sphygmomanometer. For people who experience low blood pressure without other symptoms, it may only require regular monitoring by a doctor during routine exams, and medical treatment may not be necessary. If certain signs suggest an underlying condition, your doctor may recommend one or more of the following tests to diagnose a cause for your hypotension:
In Europe hypertension occurs in about 30-45% of people as of 2013.[12] In 1995 it was estimated that 43 million people (24% of the population) in the United States had hypertension or were taking antihypertensive medication.[141] By 2004 this had increased to 29%[142][143] and further to 32% (76 million US adults) by 2017.[7] In 2017, with the change in definitions for hypertension, 46% of people in the United States are affected.[7] African-American adults in the United States have among the highest rates of hypertension in the world at 44%.[144] It is also more common in Filipino Americans and less common in US whites and Mexican Americans.[6][145] Differences in hypertension rates are multifactorial and under study.[146]
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.
As blood travels throughout your body, it presses against the walls of your blood vessels, just like water in a hose or air in a tire. This is called blood pressure. When your heart beats (contracts), squeezing blood out and pumping it into your arteries, blood pressure peaks. This is called your systolic pressure. Between heartbeats, when your heart relaxes and blood flows back into it, your blood pressure is lower. This is your diastolic pressure.
Some forms of postural hypotension may require a test called a "tilt table" test. This test evaluates the body's reaction to changes in position. The person lies on a table, is safely strapped in, and the table is raised to an upright position for up to an hour. Blood pressure, heart rate, and symptoms are recorded. Often, medications are given to help guide treatment.
The value of routine screening for hypertension in children over the age of 3 years is debated.[90][91] In 2004 the National High Blood Pressure Education Program recommended that children aged 3 years and older have blood pressure measurement at least once at every health care visit[89] and the National Heart, Lung, and Blood Institute and American Academy of Pediatrics made a similar recommendation.[92] However, the American Academy of Family Physicians[93] supports the view of the U.S. Preventive Services Task Force that the available evidence is insufficient to determine the balance of benefits and harms of screening for hypertension in children and adolescents who do not have symptoms.[94]
First, we collect and analyze statewide data using telephone surveys, hospital information, and death certificates, so we are able to know which groups of people are experiencing hypertension and the impacts of uncontrolled high blood pressure. This includes looking at geography, age, racial/ethnic status, education levels, and other demographic information. When the data is compiled, we make it available on the DOH web site. We estimate that in 2015, nearly 14,000 deaths and 71,000 hospitalizations were due to heart disease and stroke.

Electrocardiogram (ECG): This tests the heart's electrical activity. This test is more commonly used for patients at high risk of heart problems, such as hypertension and elevated cholesterol levels. The initial ECG is called a baseline. Subsequent ECGs may be compared with the baseline to reveal changes which may point to coronary artery disease or thickening of the heart wall.
Blood pressure is measured with a blood pressure cuff (sphygmomanometer). This may be done using a stethoscope and a cuff and gauge or by an automatic machine. It is a routine part of the physical examination and one of the vital signs often recorded for a patient visit. Other vital signs include pulse rate, respiratory rate (breathing rate), temperature, and weight.
High blood pressure is a common disease in which blood flows through blood vessels, or arteries, at higher than normal pressures. Blood pressure is the force of blood pushing against the walls of your arteries as the heart pumps blood. High blood pressure, sometimes called hypertension, is when this force against the artery walls is too high. Your doctor may diagnose you with high blood pressure if you have consistently high blood pressure readings.
Blood tests may be done to assess risk factors for heart disease and stroke as well as looking for complications of hypertension. These include complete blood count (CBC), electrolytes, BUN (blood urea nitrogen), and creatinine and GFR (glomerular filtration rate) to measure kidney function. A fasting lipid profile will measure cholesterol and triglyceride levels in the blood. If appropriate, blood tests may be considered to look for an underlying cause of high blood pressure (secondary hypertension)including abnormal thyroid or adrenal gland function.
You can have high blood pressure, or hypertension, and still feel just fine. That's because high blood pressure often does not cause signs of illness that you can see or feel. But, high blood pressure, sometimes called "the silent killer," is very common in older people and a major health problem. If high blood pressure isn't controlled with lifestyle changes and medicine, it can lead to stroke, heart disease, eye problems, kidney failure, and other health problems. High blood pressure can also cause shortness of breath during light physical activity or exercise.
The information you share, including that which might otherwise be Protected Health Information, to this site is by design open to the public and is not a private, secure service. You should think carefully before disclosing any personal information in any public forum. What you have written may be seen, disclosed to, or collected by third parties and may be used by others in ways we are unable to control or predict, including to contact you or otherwise be used for unauthorized or unlawful purposes. As with any public forum on any site, this information may also appear in third-party search engines like Google, MSN, Yahoo, etc. Your use of this site is governed by Harvard University and its affiliates Terms of Use located at www.health.harvard.edu/privacy-policy and may be amended from time to time.
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.
Some people have blood vessels that are stiff and lack elasticity, due to vascular disease. When this affects the tiny arteries (arterioles), the arteriolar stiffness causes increased resistance to the flow of blood and high blood pressure. This is most common in people who are also obese, have a lack of physical activity or exercise, have high salt intake, and are older.
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.
Palma Gamiz JL, et al. Iberian Multicenter Imidapril Study on Hypertension: A twelve-week, Multicenter, Randomized, Double-blind, Parallel-Group, Noninferiority Trial of the Antihypertensive Efficacy and Tolerability of Imidapril and Candesartan in Adult Patients With Mild to Moderate Essential Hypertension: the Iberian Multicenter Imidapril Study on Hypertension (IMISH).
Elevated blood pressures in the medical setting may not necessarily reflect the individuals real status. "White coat hypertension" describes a patient whose blood pressure is elevated because of the stress of the visit to the doctor or other healthcare professional, and the worry that their blood pressure might be elevated. Repeated blood pressure checks at the doctor's office or the use of a home blood pressure monitoring device may be used to confirm that you have high blood pressure.
^ Mente, Andrew; O'Donnell, Martin; Rangarajan, Sumathy; Dagenais, Gilles; Lear, Scott; McQueen, Matthew; Diaz, Rafael; Avezum, Alvaro; Lopez-Jaramillo, Patricio; Lanas, Fernando; Li, Wei; Lu, Yin; Yi, Sun; Rensheng, Lei; Iqbal, Romaina; Mony, Prem; Yusuf, Rita; Yusoff, Khalid; Szuba, Andrzej; Oguz, Aytekin; Rosengren, Annika; Bahonar, Ahmad; Yusufali, Afzalhussein; Schutte, Aletta Elisabeth; Chifamba, Jephat; Mann, Johannes F E; Anand, Sonia S; Teo, Koon; Yusuf, S (July 2016). "Associations of urinary sodium excretion with cardiovascular events in individuals with and without hypertension: a pooled analysis of data from four studies". The Lancet. 388 (10043): 465–75. doi:10.1016/S0140-6736(16)30467-6. PMID 27216139.
Hypertension, the medical term for high blood pressure, is known as "the silent killer." More than 80 million Americans (33%) have high blood pressure, and as many as 16 million of them do not even know they have the condition. If left untreated, high blood pressure greatly increases your risk for heart attack and stroke. Hypertension is projected to increase about 8 percent between 2013 and 2030.

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.


An exception to this is those with very high blood pressure readings especially when there is poor organ function.[79] Initial assessment of the hypertensive people should include a complete history and physical examination. With the availability of 24-hour ambulatory blood pressure monitors and home blood pressure machines, the importance of not wrongly diagnosing those who have white coat hypertension has led to a change in protocols. In the United Kingdom, current best practice is to follow up a single raised clinic reading with ambulatory measurement, or less ideally with home blood pressure monitoring over the course of 7 days.[79] The United States Preventive Services Task Force also recommends getting measurements outside of the healthcare environment.[80] Pseudohypertension in the elderly or noncompressibility artery syndrome may also require consideration. This condition is believed to be due to calcification of the arteries resulting in abnormally high blood pressure readings with a blood pressure cuff while intra arterial measurements of blood pressure are normal.[81] Orthostatic hypertension is when blood pressure increases upon standing.[82]
Allergic reaction (anaphylaxis): Anaphylactic shock is a sometimes-fatal allergic reaction that can occur in people who are highly sensitive to drugs such as penicillin, to certain foods such as peanuts or to bee or wasp stings. This type of shock is characterized by breathing problems, hives, itching, a swollen throat and a sudden, dramatic fall in blood pressure.
Allergic reaction (anaphylaxis): Anaphylactic shock is a sometimes-fatal allergic reaction that can occur in people who are highly sensitive to drugs such as penicillin, to certain foods such as peanuts or to bee or wasp stings. This type of shock is characterized by breathing problems, hives, itching, a swollen throat and a sudden, dramatic fall in blood pressure.
×