Diabetes mellitus is recognized by the World Health Organization as a non-infectious epidemic capable of disabling and claiming many lives a year. In diabetes mellitus, the vascular bed is damaged throughout. This does not happen with any other pathology. The main cause of death for this disease are cardiovascular diseases: myocardial infarction, heart failure.
Risk factors for heart disease in diabetes mellitus
Risk factors can be divided into two groups: non-specific, which are not directly related to diabetes, and specific, occurring only with an increased level of glucose in the blood.
Non-specific risk factors for heart disease:
- Arterial hypertension;
- Hereditary predisposition;
- Elderly age;
- Menopause in women.
Specific risk factors:
Hyperglycemia – elevated blood glucose levels. Studies have shown that the higher this indicator, the greater the risk of developing angiopathies (vascular lesion).
Insulin has an adverse effect on the walls of blood vessels, increasing the reproduction of smooth muscle cells, fibroblasts, promotes the synthesis of lipids in the walls, and also activates the coagulation system. All this leads to the development of atherosclerotic processes in the vessels.
- Insulin resistance;
Insensitivity of tissues to insulin leads to general obesity and atherosclerosis of the vascular bed, which are also risk factors for cardiovascular disease.
Features of cardiovascular disease in diabetes mellitus
Changes in the vessels and the heart are complications of diabetes. To prevent the development of heart disease in diabetes mellitus is possible by maintaining a normal level of glycemia, because we have already found out that it is specific risk factors (hyperglycemia, hyperinsulinemia, insulin resistance) that negatively affect vascular walls, leading to the development of micro- and macroangiopathies.
Heart disease is detected 4 times more often in diabetic patients. Also, studies have shown that in the presence of diabetes, the course of cardiovascular diseases has some peculiarities. Consider them with examples of individual nosologies.
For example, in hypertensive patients with diabetes mellitus, the risk of dying from heart disease is 2 times higher than in people suffering from diabetes. arterial hypertension with normal blood glucose levels. This is explained by the fact that in diabetes mellitus and in hypertension the same organs are targets:
- Coronary vessels of the heart;
- Brain vessels;
- Renal vessels;
Thus, the impact on target organs has to be with double force, and the body becomes doubly more difficult to cope with it.
Maintaining the level of blood pressure within the normative parameters reduces the risk of cardiovascular complications by 50%. That is why patients with diabetes and hypertension need to take antihypertensive drugs.
Coronary heart disease
In case of diabetes mellitus, the risk of developing coronary heart disease increases, and all of its forms, including painless ones:
- Angina pectoris;
- Myocardial infarction;
- Heart failure;
- Sudden coronary death.
Coronary heart disease can manifest as angina pectoris – acute episodes of pain in the heart or behind the sternum and shortness of breath.
In the presence of diabetes, stenocardia develops 2 times more often, a feature of which is painless. In this case, the patient complains not on attacks of chest pain, but on the heartbeat, shortness of breath, and the appearance of sweat.
Atypical angina pectoris variants that are more unfavorable in terms of prognosis — unstable stenocardia and Prinzmetal stenocardia often develop.
Mortality from myocardial infarction diabetes is 60%. Cardiac muscle infarction develops with the same frequency in both women and men. A feature is the frequent development of its painless forms. This is due to damage to blood vessels (angiopathy) and nerves (neuropathy), inevitably developing in diabetes mellitus.
Another feature is the development of lethal forms of myocardial infarction – changes in the vessels, nerves and muscle of the heart do not allow the heart to recover from ischemia. This factor is also associated with a higher percentage of post-infarction complications in diabetics compared with persons who do not have this disease in history.
The development of heart failure in diabetes mellitus occurs 4 times more often. Contributes to this formation of the so-called “diabetic heart”, which is based on a pathology, called cardiomyopathy.
Cardiomyopathy is the primary lesion of the heart by any factors leading to an increase in its size with the formation of heart failure and rhythm disturbances.
Diabetic cardiomyopathy develops due to the development of changes in the vascular walls – the heart muscle loses the necessary amount of blood, and with it oxygen and nutrients, which leads to morphofunctional changes in cardiomyocytes. And changes in the nerve fiber with neuropathy lead to impaired electrical conductivity of the heart. Cardiomyocyte hypertrophy develops, hypoxic processes lead to the formation of sclerotic processes between myocardial fibers – all this leads to an expansion of the cardiac cavities and loss of elasticity of the heart muscle, which negatively affects the contractility of the myocardium. Heart failure develops.
Sudden coronary death
Studies conducted in Finland have shown that in patients with diabetes mellitus the risk of death from heart disease is equal to that in individuals who have had a myocardial infarction, but who do not have a history of hyperglycemia.
Also diabetes is one of the risk factors for the development of sudden coronary death, in which the patient’s death occurs in a short time from ventricular fibrillation or arrhythmia. In addition to diabetes, risk factors include coronary heart disease, cardiomyopathy, obesity, history of myocardial infarction, heart failure – and these are frequent “satellites” of diabetes. Due to the presence of a whole “bunch” of risk factors – the development of sudden cardiac death in diabetes mellitus occurs more often than in a population not suffering from this disease.
Thus, heart disease and diabetes – related diseases – one weights for the course and prognosis of the other.