Blood pressure is the force exerted by circulating blood on the walls of blood vessels. It constitutes one of the critically important signs of life or vital signs, which include heart rate, breathing, and temperature. Blood pressure is generated by the heart pumping blood into the arteries modified by the response of the arteries to the flow of blood.
Blood pressure is the force of blood pushing against the walls of arteries. When the doctor measures your blood pressure, the results are given in two numbers. The first number, called systolic blood pressure, is the pressure caused by your heart contracting and pushing out blood. The second number, called diastolic blood pressure, is the pressure when your heart relaxes and fills with blood. Your blood pressure reading is usually given as the systolic blood pressure number over the diastolic blood pressure number, such as 138/72. Normal blood pressure for adults is defined as a systolic pressure of less than 120 and a diastolic pressure of less than 80. This is stated as 120/80.
Exercise stress test: More commonly used for patients with borderline hypertension. This usually involves pedaling a stationary bicycle or walking on a treadmill. The stress test assesses how the body's cardiovascular system responds to increased physical activity. If the patient has hypertension this data is important to know before the exercise test starts. The test monitors the electrical activity of the heart, as well as the patient's blood pressure during exercise. An exercise stress test sometimes reveals problems that are not apparent when the body is resting. Imaging scans of the heart's blood supply might be done at the same time.
Strong Heart Study. Since 1988, the NHLBI has supported the Strong Heart Study (SHS), the largest epidemiologic study of American Indians ever conducted. The SHS aims to estimate the impact of heart and blood vessel diseases and to assess how common and significant standard risk factors are in this community. Thirteen tribes and communities in four states participate in the study. Visit Strong Heart Study for more information.
As of 2014, approximately one billion adults or ~22% of the population of the world have hypertension. It is slightly more frequent in men, in those of low socioeconomic status, and it becomes more common with age. It is common in high, medium, and low income countries. 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. Rates in Africa were about 45% in 2016.
Blood pressure control is a lifelong challenge. Hypertension can progress through the years, and treatments that worked earlier in life may need to be adjusted over time. Blood pressure control may involve gradually making lifestyle changes like diet, weight loss, exercise, and possibly taking medicine if necessary. In some situations, medications may be recommended immediately. As with many diseases, you and your doctor should work together to find the treatment plan that works for you.
About This Image: Chart showing potential causes of low blood pressure The risk of low and high blood pressure commonly increases as a person ages due in part to changes during the aging process. The flow of blood to a person's heart muscle and brain declines as a person ages, many times as a result of plaque buildup in their blood vessels. Approximately 10-20% of people over the age of 65 experience postural hypotension. While the causes of low blood pressure may not always be clear, it might be associated with things such as:
For a normal reading, your blood pressure needs to show a top number (systolic pressure) that’s between 90 and less than 120 and a bottom number (diastolic pressure) that’s between 60 and less than 80. The American Heart Association (AHA) considers blood pressure to be within the normal range when both your systolic and diastolic numbers are in these ranges.
Blood pressure rises with aging and the risk of becoming hypertensive in later life is considerable. Several environmental factors influence blood pressure. High salt intake raises the blood pressure in salt sensitive individuals; lack of exercise, obesity, and depression can play a role in individual cases. The possible roles of other factors such as caffeine consumption, and vitamin D deficiency are less clear. Insulin resistance, which is common in obesity and is a component of syndrome X (or the metabolic syndrome), is also thought to contribute to hypertension. One review suggests that sugar may play an important role in hypertension and salt is just an innocent bystander.
Pulse pressure (the difference between systolic and diastolic blood pressure) is frequently increased in older people with hypertension. This can mean that systolic pressure is abnormally high, but diastolic pressure may be normal or low a condition termed isolated systolic hypertension. The high pulse pressure in elderly people with hypertension or isolated systolic hypertension is explained by increased arterial stiffness, which typically accompanies aging and may be exacerbated by high blood pressure.
^ Jump up to: a b Acierno, Mark J.; Brown, Scott; Coleman, Amanda E.; Jepson, Rosanne E.; Papich, Mark; Stepien, Rebecca L.; Syme, Harriet M. (2018-10-24). "ACVIM consensus statement: Guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats". Journal of Veterinary Internal Medicine. 32 (6): 1803–1822. doi:10.1111/jvim.15331. ISSN 1939-1676. PMC 6271319. PMID 30353952.
High blood pressure is classified as either primary (essential) high blood pressure or secondary high blood pressure. About 90–95% of cases are primary, defined as high blood pressure due to nonspecific lifestyle and genetic factors. Lifestyle factors that increase the risk include excess salt in the diet, excess body weight, smoking, and alcohol use. 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.
The drug of choice for hypertensive, pregnant women is one of the oldest high blood pressure medications on the market. Methyldopa, which works to lower blood pressure through the central nervous system, has the lowest risk of harming the mother and developing fetus. Other possible safe options include labetalol, beta blockers, and diuretics. Two classes of drugs which should never be used during pregnancy include the ACE inhibitors and the angiotensin II receptor blockers.
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).
Once the diagnosis of hypertension has been made, healthcare providers should attempt to identify the underlying cause based on risk factors and other symptoms, if present. Secondary hypertension is more common in preadolescent children, with most cases caused by kidney disease. Primary or essential hypertension is more common in adolescents and has multiple risk factors, including obesity and a family history of hypertension. Laboratory tests can also be performed to identify possible causes of secondary hypertension, and to determine whether hypertension has caused damage to the heart, eyes, and kidneys. Additional tests for diabetes and high cholesterol levels are usually performed because these conditions are additional risk factors for the development of heart disease and may require treatment.
Blood pressure readings fall into four general categories, ranging from normal to stage 2 high blood pressure (hypertension). The level of your blood pressure determines what kind of treatment you may need. To get an accurate blood pressure measurement, your doctor should evaluate your readings based on the average of two or more blood pressure readings at three or more office visits.