Overview: What is high blood pressure?
In medical terminology, high blood pressure is also known as arterial hypertension or hypertension. In this case, the pressure in the blood vessels that carry blood away from the heart exceeds a certain limit. According to the general definition of the medical associations, one speaks of high blood pressure if the values are at least 140 to 90 mm Hg in different measurements on different days.
A certain pressure in the arteries is necessary for the blood to flow in the circulation. This is ensured by the heartbeat and the tension of the vascular walls. Blood pressure is measured in millimeters of mercury (mm Hg). A distinction is made between two values:
- The first (upper) value indicates the systolic blood pressure. Systole is the phase in which the heart muscle contracts and pumps blood into the arteries.
- The second (lower) value indicates the diastolic blood pressure. Diastole describes the phase in which the heart muscle relaxes again after contraction and fills with blood.
High blood pressure (hypertension) is not a disease in its own right. However, hypertension is considered an important risk factor for various diseases such as heart attacks and strokes.
High blood pressure – frequency and age
High blood pressure is widespread. In Europe, around 30 percent of people suffer from it. In Switzerland, it is estimated that one in four adults has high blood pressure. That is the equivalent of around 1.5 million people.
Hypertension is rare in childhood, adolescence and early adulthood. The frequency increases with age. Women and men over the age of 60 are particularly at risk. In this age group, every second person has high blood pressure. The tricky thing is that around a third of those affected do not know that their blood pressure is too high.
High blood pressure: causes and risk factors
Around 90 percent of people with high blood pressure suffer from primary or essential hypertension. In this form, no direct causes can be identified. It occurs more frequently with increasing age. This is not the case with secondary hypertension, which affects around ten percent of people. In this case, high blood pressure is the result of a disease, certain substances or other triggers. Depending on the type of high blood pressure, there are various possible causes.
Primary hypertension
The most important risk factors for primary (essential) hypertension include
- hereditary (genetic) predisposition: If one or both parents are affected, the risk of hypertension in children increases two to threefold. In rare cases, genetic defects – together with external factors – are also responsible for high blood pressure.
- Lack of exercise: Too little exercise and being overweight promote the development of hardening of the arteries (arteriosclerosis). As a result, blood pressure rises due to the narrowing of the arteries.
- Unhealthy diet: A high salt intake has the effect of increasing blood pressure in salt-sensitive people. This means that these people are sensitive to table salt. A lot of salt is contained in convenience products in particular.
- Overweight: Obesity causes blood vessels to lose their elasticity. At the same time, the kidneys release messenger substances that increase blood pressure.
- Stress: Certain stress hormones (catecholamines) cause the muscles of the blood vessels to contract and vascular resistance to increase.
- Alcohol: It makes the heart beat faster and pumps more blood into the arteries. Even small amounts of alcohol are sufficient for this.
- Nicotine: Nicotine increases the risk of heart attacks or strokes, which are often associated with high blood pressure.
Secondary hypertension
Secondary hypertension can be caused by the following factors:
- Medication: Decongestant nasal drops with vasoconstrictor agents and anti-inflammatory drugs such as ibuprofen or diclofenac.
- Substances: In addition to drugs or toxic substances, excessive consumption of licorice can also drive up blood pressure.
- Hormones: Both hormone-containing medication and the body’s own hormones can cause high blood pressure: These include cortisone preparations (e.g. for asthma) and some birth control pills. Diseases of the adrenal glands with an overproduction of aldosterone, cortisol or adrenaline/noradrenaline and, more rarely, hyperthyroidism increase high blood pressure.
- Diseases: Vascular inflammation, narrowing of the aorta (aortic isthmus stenosis), kidney and lung diseases can also be responsible for high blood pressure.
- Snoring: Prolonged pauses in breathing during sleep (sleep apnea) cause blood pressure to rise in the long term.
- Pregnancy: Secondary hypertension can occur particularly in older expectant mothers (> 40 years) and multiple pregnancies.
Symptoms: High blood pressure
High blood pressure develops silently. As it does not usually cause any pain, it often goes unnoticed for a long time. For example, one in three people affected do not know that their blood pressure is too high. It can therefore take years or decades before the first symptoms appear.
However, this is treacherous: in the long term, high blood pressure can damage the heart, blood vessels, brain, eyes and kidneys. As a result, the risk of heart attack, stroke or kidney disease increases. It is therefore all the more important to have your values checked as part of a regular health check-up and to look out for warning signs.
The possible symptoms of high blood pressure include
- Headache
- Dizziness
- Nosebleed
- Ringing in the ears
Signs of organ damage that has already occurred can include
Important to know: Stroke-like symptoms such as dizziness, visual disturbances, signs of paralysis or impaired consciousness are signs of a hypertensive emergency. The blood pressure values are then usually above 230 to 130 millimeters of mercury (mm Hg) and must be lowered quickly because otherwise they can damage organs such as the brain, eyes or heart. In this case, you should call the emergency number 144 immediately.
If blood pressure is very high but there are no symptoms, a hypertensive crisis may be present. In contrast to a hypertensive emergency, high blood pressure does not need to be lowered immediately with medication. Nevertheless, you should have this clarified promptly by a doctor or in hospital.
High blood pressure: Diagnosis by us
We will measure your blood pressure several times before we can make a diagnosis of hypertension. We will ensure that there is a rest period of three to five minutes before the first measurement, that the measurement is taken in a sitting position and that there is an interval of one to two minutes between each measurement.
Hypertension is present if blood pressure values of at least 140 to 90 mm Hg are measured three times over several days.
In order to make a reliable diagnosis, a 24-hour outpatient measurement is also useful in many cases. In this case, you will receive a device that automatically measures your blood pressure on a regular basis and records it for 24 hours. For affected persons with cardiovascular risk factors, we can also arrange an exercise test on the ergometer.
Many patients are upset in the doctor’s office. This can drive up the blood pressure and thus falsify it. Self-measurement not only helps with diagnosis, but also with subsequent treatment in order to monitor the success of the therapy.
Devices that measure blood pressure on the upper arm are particularly recommended. Make sure that the size of the blood pressure cuff matches the circumference of the upper arm. The best time to take your own blood pressure is in the morning and in the evening before eating and taking medication. The blood pressure monitor should bear a seal of approval (e.g. from the German Hypertension League) that confirms the accuracy of the measurement.
High blood pressure: additional examinations
In addition to the blood pressure values, we will also take into account your risk factors for cardiovascular diseases such as smoking, obesity, lack of exercise, diabetes mellitus, elevated blood lipid levels and existing organ damage and concomitant diseases in order to make a correct diagnosis.
Various further examinations may therefore be useful. These include:
- Blood test
- Urinalysis
- Examination of the fundus of the eye
- Electrocardiogram (ECG)
- Ultrasound of the heart (echocardiography) and kidneys
- X-ray images
- Hormone analyses
High blood pressure consultation
In our hypertension consultation, we also clarify rare causes of hypertension, optimize medication and are able to offer selected patients interventional techniques such as renal nerve ablation.
High blood pressure: prevention, early detection, prognosis
The good news is that in many cases you can prevent high blood pressure (hypertension) or reduce high blood pressure levels. A healthy lifestyle plays an important role here. This means: Through
- regular exercise,
- healthy nutrition,
- a normal body weight and
- Stress management
- Regular and sufficient sleep
you can actively help to prevent your blood pressure from becoming too high in the first place or to bring it down again.
If you already have to take antihypertensive medication, it is important that you adhere to the prescribed therapy – even if the hypertension is not (yet) causing any symptoms. In this way you can avoid possible consequential damage to the heart and blood vessels or reduce the risk.
Progression and prognosis of high blood pressure
Hypertension often progresses for years without symptoms and is only discovered late. However, the longer the blood pressure remains high, the more it can damage the body.
This primarily affects the cardiovascular system, but also the cerebral circulation and the kidneys:
- The left ventricle enlarges due to the permanent pressure load in the cardiovascular system. A possible consequence is heart failure (cardiac insufficiency). High blood pressure also promotes hardening of the arteries (arteriosclerosis) in the coronary arteries and other parts of the body. This increases the risk of chest tightness (angina pectoris), coronary heart disease, heart attacks and circulatory disorders in the legs as well as a sometimes life-threatening widening of the aorta (aortic aneurysm).
- Another complication affects the brain. High blood pressure is considered the greatest risk factor for stroke. Data shows that up to 70 percent of all strokes in people over the age of 65 occur as a result of hypertension.
- High blood pressure also frequently leads to kidney damage. The high levels damage the small vessels in the kidney, causing kidney tissue to die. As a result, kidney function deteriorates, which can lead to kidney failure. In this case, blood washing (dialysis) or a kidney transplant may be necessary.
Early diagnosis and treatment is therefore crucial for high blood pressure, improves the prognosis and can prevent secondary diseases.
Multidisciplinary commitment
As the causes and consequences of hypertension always affect several organ systems, its diagnosis and treatment require a comprehensive, multidisciplinary approach. At the USZ, all the disciplines involved (cardiology, endocrinology, angiology, nephrology, pneumology, internal medicine, radiology and visceral surgery) therefore work hand in hand under one roof. Our daily endeavor is to always offer each patient the best possible and most efficient diagnosis and treatment and at the same time to help develop these ourselves. The Hypertension Research Network (HYRENE) has dedicated itself to this goal. Several research groups at the USZ and the University of Zurich are working hard in this unique network to gain new insights into the field of hypertension and make them available to patients.
High blood pressure: effective treatment
Early treatment of high blood pressure (hypertension) is important to prevent organ damage and secondary diseases such as heart attacks and strokes.
The aim is to reduce the high blood pressure to such an extent that values below 140 to 90 millimeters of mercury (mm Hg) are achieved at rest. As a rule, antihypertensive medication should only be used above this threshold value. In the case of high-normal values (130-139 to 85-89 mm Hg), the European guidelines stipulate lifestyle changes as a therapeutic measure. For people with cardiovascular disease, blood pressure lowering measures are indicated even at high-normal values.
