Causes of High Blood Pressure
There are two forms of high blood pressure:
- primary hypertension (common)
- secondary hypertension (rare)
Secondary hypertension is usually a consequence of other diseases.
Blood Pressure
The human heart cycle always goes through two phases: systole (pumping phase) and diastole (filling phase). This creates a systolic and a diastolic pressure in the vessels. When the heart contracts, the systolic (higher) pressure occurs. During the heart's relaxation, the diastolic (lower) pressure occurs. Additionally, blood pressure is influenced by the large elastic arteries close to the heart and smaller resistance vessels (organ arteries). The pressure due to increased heart output responds in healthy individuals according to physical demands, ensuring adequate blood flow at all times.
However, blood pressure should not be seen as a constant value and fluctuates at different times of the day. For example, blood pressure decreases during nighttime rest and is higher during the day (see Blood Pressure Throughout the Day). Furthermore, blood pressure often increases with age. Physical activity can also lead to an increase in blood pressure. For patients with high blood pressure, this can be dangerous, as blood pressure during physical activity (especially strength training) can reach peaks that may be life-threatening. In contrast, endurance sports like running, cycling, or cross-country skiing can have the opposite effect and can lower blood pressure in the long term.
Causes of High Blood Pressure
Primary high blood pressure, which occurs independently of a specific underlying condition, is favored by certain risk factors that can partly be influenced by lifestyle. These include
- overweight and abdominal obesity
- smoking
- lack of exercise
- too much alcohol
- chronic stress
- table salt (partly)
Risk factors that cannot be influenced include, among others
- age
- gender
- genetic predisposition
If there is already a predisposition to high blood pressure, the modifiable risk factors can significantly influence the development of high blood pressure.
Risk Factors for Developing Primary Hypertension
Overweight and Abdominal Obesity
Overweight (BMI of 25 or higher, obesity from 30) can promote high blood pressure, as the heart and its work are more heavily taxed. However, it is not just overweight itself that is a risk factor. Since blood pressure often increases as a result of insulin resistance associated with obesity, the distribution of fat deposits also matters. Especially the abdomen and waist should be monitored, as abdominal fat contributes to muscle, fat, and liver cells responding poorly to insulin. The body requires more insulin, which increases the risk of type 2 diabetes. When overweight, hypertension, and diabetes mellitus occur together, this is referred to as metabolic syndrome.
Nicotine not only affects the coronary arteries and leg arteries. It causes constriction of all blood vessels. The harmful substances (especially free radicals) lead to the destruction of the blood vessel's ability to dilate (endothelium). This promotes arteriosclerosis (hardening of the arteries). As a result of the deterioration in the flow properties of the blood, there is a permanent increase in blood pressure.
Lack of exercise generally weakens the body. The heart cannot work efficiently. Even with minor exertion, it runs at full speed. Physical activity can long-term lower both the systolic (upper measurement) and diastolic (lower measurement) values in patients with high blood pressure.
Alcohol in larger quantities can temporarily lead to an increase in blood pressure. With consistently high consumption, chronic high blood pressure can develop. Alcohol not only has a harmful effect on the heart and circulation and thus on blood pressure, but also on the brain and liver.
Stress that is not balanced or overcome for a long time can increase blood pressure through the autonomic nervous system. The part referred to as the "sympathetic" is responsible for controlling vital functions such as blood pressure and circulation. Thanks to it, rapid increases in performance are possible, which is why it is also significantly involved in the response to stress. The so-called "parasympathetic" transmits calming impulses for relaxation and stress relief. Unmanaged stress can also lead to sleep disorders, which also negatively affect blood pressure. With a high stress level, the body remains in a state of constant tension and cannot recover.
By consuming sodium chloride, i.e., table or cooking salt, the smaller arteries involved in pressure regulation react more sensitively to circulatory hormones. This can lead to an increase in blood pressure. The DGE (German Nutrition Society) recommends a daily salt intake of a maximum of 6 grams, which is about one teaspoon. If treatment for high blood pressure is already underway, it can be complicated by too much salt and facilitated by less salt.
Causes of Secondary Hypertension
The causes of secondary hypertension are usually due to an underlying condition. These often include metabolic disorders, kidney diseases, or vascular diseases. A congenital narrowing of the aorta can also be a cause. Hormonal medications (such as birth control pills) or rheumatism drugs, as well as certain drugs (such as amphetamines, cocaine), are also possible causes of high blood pressure.
Special Form of Secondary Hypertension: Pregnancy-Induced High Blood Pressure
The pregnancy-induced high blood pressure is a special form of secondary hypertension. It has no disease as a cause. Rather, the pregnancy and the changes associated with it trigger high blood pressure. About six to eight percent of all expectant mothers are affected by this form of hypertension. The risk is significantly higher for women over 40 or in multiple pregnancies. The causes are known as hypertensive pregnancy disorders (such as preeclampsia, eclampsia, HELLP syndrome), which can develop rapidly and pose a risk to both mother and child. Therefore, regular blood pressure checks are conducted during pregnancy.
Sources:
By Sabine Croci.
This article is medically reviewed. Last updated (01/2024).
Information on the website and within the app cannot replace a consultation with a doctor, but can certainly complement it.
