General information
Smoking cigarettes or other tobacco products entails many health risks. In addition to the loss of lung function and other consequential damage, circulatory disorders can develop. With circulatory disorders, areas of the body are no longer supplied with sufficient blood, which damages the tissue.
This is usually caused by changes in the vascular system, which can no longer conduct the blood completely or, in the worst case, not at all. Other causes of circulatory disorders are high blood pressure, diabetes and other metabolic diseases. While the factors mentioned so far represent diseases that can be treated but are not in the hands of the patient, smoking and an unhealthy diet are among the causes that can be influenced. Every smoker has to decide for himself, but also for people in his immediate environment, whether it is worthwhile to maintain this health-endangering vice. In principle, the consumption of tobacco products is not advisable.
Development of circulatory disorders
Smoking tobacco produces various gases which are inhaled. One of the gases is carbon monoxide (CO). This is stored in the red blood cells in the blood, the so-called erythrocytes.
Normally, erythrocytes bind the oxygen that is absorbed in the lungs when breathing. The oxygen deficiency caused by the erythrocytes coated with carbon monoxide is measured in the body and communicated to the brain. This is done via the so-called Glomus caroticum – a measuring station in the carotid artery (Arteria carotis communis) – in which the concentration of carbon dioxide (CO2), which is produced by metabolism in the body and is breathed out through the lungs, and oxygen (O2) and the pH value of the blood are registered.
Through the unavailable red blood cells, the brain signals to the bone marrow that there is a deficiency of these and promotes new formation. As a result, an increased number of erythrocytes are produced and the hematocrit value, the volume proportion of blood cells in the blood, increases. This causes the blood to thicken.
Besides influencing blood formation, the involuntary (vegetative) nervous system is stimulated. This releases stress hormones – adrenaline and noradrenaline. These put the body into an activated state.
Part of the activation is the narrowing of the blood vessels in the body (vasoconstriction), which causes the blood pressure to rise. Furthermore, the blood lipid values change. The concentration of harmful LDL cholesterol rises due to the lack of oxygen in the tissue and there is increased storage in the vessel wall.
This is usually the beginning of arteriosclerosis, a pathological narrowing of an artery due to fat storage and subsequent calcification of the damaged vessel wall. This increases the risk of a blood clot forming in the vessel, a so-called thrombus. HDL cholesterol, which is popularly known as “good cholesterol”, is produced in a reduced form by smoking.
As a result, its useful function of inhibiting the storage of LDL cholesterol is lost and additionally increases this negative effect. Smoking also affects the coagulation system. Fibrinogen is produced in greater quantities.
Fibrinogen is the precursor of fibrin, one of the clotting factors. The increased release of fibrin increases the blood’s tendency to clot, i.e. unnecessary and spontaneous thrombus formation can occur, which, depending on the size of the vessel, can lead to its occlusion. The formation of a blood clot is caused by the increased cross-linking of blood platelets (thrombocytes), which are involved in blood clotting to a large extent.
Overall, the concentration of fibrinogen influences the flowability (viscosity) of the blood. This factor can also lead to blood thickening. All the mechanisms of formation have one thing in common: their effect on the vascular system.
Smoking causes blood pressure to rise, the vessels contract and are additionally constricted by arteriosclerotic processes. The latter effect plays the greatest role in the manifestation of the circulatory disorder. Since the vascular system contains many interconnected pathways (anastomoses), the occlusion of individual arteries is not yet noticed in most cases. Only when the majority of the accesses are stenosed (closed) does a noticeable circulatory disturbance due to smoking occur.
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