A. Blood Pressure Measurement
Blood pressure reading
Blood pressure readings tell us something about the pressure in arterial blood circulation. A blood pressure meter reads both periodic blood pressure values generated by constriction (systole) and slackening (diastole) of the heart muscle.
Systolic blood pressure:
If the blood is expelled into the arteries of the body by the constriction of the cardiac muscle this results in high pressure. That phase of cardiac activity is called the systole. The increase in pressure during this phase is measured and called systolic blood pressure.
Diastolic blood pressure:
After the systole, the heart muscle slackens and relaxes (cardiac rest). This phase is called the diastole. The pressure at this point drops compared with the constriction phase and represents the diastolic blood pressure. The diastolic pressure is always the lower number measured.
Blood pressure values
Blood pressure varies extremely and adjusts to internal and external influences, such as physical activity, body weight and age. Too high or too low pressure which could lead to organ damage can be avoided by regulating arterial pressure. In Germany and Switzerland, the blood pressure must be measured in millimetres of mercury (mmHg) by law.
The following classification for systolic and diastolic blood pressure was established in accordance with the World Health Organisation (WHO) and the International Hypertension Society:
|Systolic (mmHg)||Diastolic (mmHg)|
|Optimal||< 120||and||< 80|
|Normal||< 130||and||< 85|
|High normal||130 - 139||or||85 - 89|
|Hypertension (1st degree)||140 - 159||or||90 - 99|
|Hypertension (2nd degree)||160 - 179||or||100 - 109|
|Hypertension (3rd degree)||≥ 180||or||≥ 110|
This classification of blood pressure categories primarily relates to otherwise healthy people and tells us nothing about the necessity for a medical intervention. "Normal" and "optimal" are descriptions of a condition without further significance for therapeutic intervention.
High blood pressure
A chronic increase in arterial blood pressure (systolic blood pressure > 140 mmHg and diastolic blood pressure > 90 mmHg), is defined as hypertension and is the most frequent cardiovascular disease worldwide. In general, systolic blood pressure continues to rise until around the age of 80. In contrast, diastolic blood pressure increases until around the age of 50 and then drops again. This leads to an increasing difference between systolic and diastolic blood pressure from middle age onwards.
While an acute increase in blood pressure only rarely leads to clinical symptoms or pathological changes, constant high blood pressure/hypertension can cause permanent damage to the heart and blood vessels in the long term. High blood pressure is generated by an increase in arterial vascular resistance. In chronic conditions, the very flexible vascular wall of the arteries actually becomes more rigid, which can lead to hardening and narrowing with increasing calcification of the vascular wall (arteriosclerosis). This development usually progresses unnoticed, which is a danger for the patient, as hypertension is not felt! It is only when some vessels or organs have already become severely - and sometimes irreversibly - damaged that the patient feels pain and goes to see the doctor. This can relate to 3rd degree blood pressure values. The first signs of possible hypertension can be headaches, dizziness, vision impairment, shortness of breath, tenseness or pains in the left side of the chest.
High blood pressure is an illness to be taken seriously and if left untreated, can cause damage to the heart, eyes and brain for example. The connection between blood pressure and the risk of cardiovascular disease is exponential rather than linear. Hypertension is the number 1 risk factor for heart attack, heart failure, stroke and renal failure.
B. Causes and risk factors for high blood pressure
The frequency of high blood pressure increases significantly with age and body weight. In Germany, nearly one in three adults become ill with hypertension in the course of their lives. Over the age of 65, more than 50% of the population is affected. For most people there is no recognisable clear cause for the disease. This type of development of high blood pressure is called essential or primary hypertension. Around 90% of all hypertension cases are of primary nature. The occurrence of primary hypertension often has many causes, while a genetic/family assessment commonly plays a role too.
In some cases however (10% of all hypertensive patients), renal (kidney) or endocrine diseases, or medicines (e.g. non-steroidal anti-inflammatory drugs, birth control pills), can lead to high blood pressure (secondary hypertension). But other types of secondary hypertension can also have neurogenic or psychogenic triggers.
In addition, various risk factors can have a negative influence on the consequences of high blood pressure for general health. High blood lipids, diabetes, nicotine and alcohol consumption, stress, excess weight and lack of physical exercise increase the risk of serious cardiovascular diseases.
C. Diagnosis of high blood pressure
Hypertension is diagnosed by a doctor, who clarifies the degree of severity and the cause (primary or secondary hypertension). In addition, the doctor records the general medical status of the patient within this context and clarifies risk factors and possible concomitant diseases. Blood pressure readings play a crucial role in diagnosing hypertension.
Direct and indirect blood pressure reading
Along with the direct, invasive blood pressure measurement using a catheter, which can only be carried out in intensive-care units, the indirect, so-called sphygmomanometric method, based on the first studies of the Italian doctor, Scipione Riva-Rocci, is used in outpatient clinics and for self-monitoring. Although this measurement is not as accurate as the direct procedure, it is both non-aggressive and cost-effective, and can be performed simply and quickly. Auscultation, palpation or oscillation methods can be used to take the reading. These days, auscultatory reading is the standard procedure for the upper systolic and the lower diastolic values. An inflatable cuff is placed on the upper arm, which should be positioned at the same level as the heart. The cuff is inflated with a rubber ball and this causes a measurable counter-pressure, which compresses the arteries in the upper arm until no more blood flows into them. The pressure in the cuff is increased until no sound can be heard with a stethoscope under the cuff. Then the air in the cuff is slowly released. Once the pulse can be felt again or a whooshing sound (the so-called Korotkoff sound) can be heard, the systolic (upper) value can be read. Finally, the air is let out further. When no sound can be heard or the pulse can no longer be felt, the diastolic (lower) value can be read.
D. Therapy options for high blood pressure
Drug therapy is often avoided in less serious cases of high blood pressure. The treatment is primarily aimed at reducing accompanying risks or getting them under control. It is therefore less concerned with reducing blood pressure values than achieving a successful better prognosis for the patients. The patient can have a very beneficial effect on the subsequent course of therapy and influence the end result. In many cases very good results can be achieved with healthy and balanced nutrition, avoiding alcohol and drugs, weight control and physical exercise. The doctor will prescribe drugs only if these measures do not lead to sustainable success or improvement. These days, doctors have a range of drugs and combination preparations at their disposal. The selection and application of such drugs depends on the degree of severity of the hypertension and patient-specific data.
Recommendations for blood pressure monitoring in the home
- Take the blood pressure measurement lying down or sitting
- Take the reading after a 5-minute rest
- Keep a blood pressure log
If you are affected by hypertension, you can do a lot to help yourself and support the medical therapy. Through personal discipline and motivation, you can introduce lifestyle changes that considerably influence the effects and consequences of hypertension. These include:
- Healthy nutrition (low-fat and low-salt, plenty of vegetables and fruit)
- Low consumption of alcohol
- No nicotine or other drugs
- Physical exercise
- Weight loss
- Relaxation breaks during the day
- Avoiding stressful psychological and social influences