Hyperlipidemia is an abnormal increase in the lipoprotein content of various fractions in the circulating blood. The fact of the presence of hyperlipidemia in humans is a risk factor for the onset of chronic progressive heart and vascular diseases, aggravating this pathology. In addition, a significant increase in various fractions of lipids contributes to the development of signs of pancreatitis.
Due to the fact that the overwhelming majority of lipid fractions take an indirect part in the formation of atheromatous occlusive lumens of the plaque vessels, this state sooner or later leads to trophic disturbances in all tissues of the human body, due to the effect of prolonged ischemia.
According to world statistics, about a quarter of the world's population suffers from pathologies due to increased levels of lipids in the plasma, especially cholesterol. In the course of randomized trials, it has been shown that for men, physiological elevated lipidogram indices are characteristic in comparison with female representatives. And women have a compensatory increase in lipids during the onset of menopause.
Causes of hyperlipidemia
The process of excessive accumulation of various lipid fractions in the human body, namely, in blood plasma, is affected by a large number of etiopathogenetic factors, some of which are amenable to correction by medicinal and non-medicament methods, while others are classified as permanent risk factors.
Non-modifiable etiopathogenetic factors of the signs of hyperlipidemia are:
- Sexual accessory (men are more predisposed to the development of signs of some form of hyperlipidemia);
- elderly patient;
- burdened heredity for the predisposition to the occurrence of diseases accompanied by hyperlipidemia.
The presence of one or a combination of these factors in the patient is the basis for the use of preventive measures to prevent complications arising on the background of pronounced prolonged hyperlipidemia.
Yet a large group of factors provoking the development of hyperlipidemia are modified etiopathogenetic mechanisms, and in most cases the elimination of these causes is accompanied by a partial or complete leveling of signs of elevated lipid levels. This group of reasons are:
- prolonged systematic use of foods saturated with low-density lipoproteins and triglycerides;
- Overweight due to the massive development of adipose tissue;
- complete absence of physical activity;
- uncontrolled hyperglycemia in patients with long-term diabetes mellitus, contributing to severe impairment of pancreatic function;
- disorders of the hormonal status with prevailing changes in the thyroid gland;
- The period of pregnancy, especially the last trimester, is often accompanied by transient physiological hyperlipidemia, which has no serious consequences and in most cases is leveled in the early postpartum period ;
- Continuous systematic intake of certain groups of drugs (combined hormonal contraceptives, corticosteroids).
Symptoms of hyperlipidemia
Due to the fact that hyperlipidemia is nothing more than a clinical and laboratory syndrome, there are no specific clinical manifestations that distinguish it from other pathologies. Clinical signs begin to manifest only when the signs of atherosclerotic disease develop, and the degree of their manifestation has a clear dependence on the spread and severity of the process.
Even against the background of complete well-being in a patient with hyperlipidemia, there is a risk of severe complications of the cardiovascular profile. In this regard, all people with relatives suffering from any vascular pathology, it is recommended to regularly check for lipid fractions in the blood to exclude hyperlipidemia.
A prerequisite for a laboratory analysis called "lipidogram" is the patient's preliminary preparation, which consists in the complete exclusion of meals at least 14 hours before the study. During the development of acute myocardial infarction, there are significant changes in the lipidogram with increased cholesterol, and signs of recurrent myocardial infarction are the predominance of triglycerides in the lipidogram.
Types of hyperlipidemia
Lipidogram is the determination of a large number of indicators of different lipid fractions and the classification of hyperlipidemia is based on the prevalence of certain indicators. There is, as an isolated increase in one of the fractions, and an increase in all a large number of indicators, resulting in a mixed hyperlipidemia.
Primary, or hereditary hyperlipidemia, is divided according to the etiopathogenetic principles of its occurrence into five types:
- the first type of hyperlipidemia is currently a rare pathology, and the pathogenetic mechanism of its occurrence is based on the expressed lipoprotein lipase activity deficiency, accompanied by an increased content of chylomicrons and triglycerides in plasma. This form of hyperlipidemia has nothing to do with the development of atherosclerotic changes and is more likely to affect the function of the pancreas. Correction of this hyperlipidemia consists in a sharp restriction of the consumption of fats;
- familial hyperlipidemia of the second type is due to stimulation of the formation of beta-lipoproteins or delayed destruction thereof, thereby creating conditions for excessive accumulation of low density lipoproteins. The debut of hyperlipidemic changes occurs in children's age, and in the young period most patients already have signs of atherosclerotic heart disease. About 30% of cases of familial hyperlipidemia are accompanied by development of signs of acute circulatory disturbances in the system of coronary and cerebral large arterial vessels;
- the third type of hyperlipidemia is extremely rare and the appearance of its signs is due to the blood content of the abnormal lipoprotein. The lipidogram of this category of patients undergoes significant changes with the prevalence of very low density lipoproteins, which in a short period of time provoke the formation of atherosclerotic plaques;
- Hyperlipidemia of the fourth type, which is based on an elevated plasma content of triglycerides, is the most frequent form of lipid metabolism disorder. The risk group for this disease is middle-aged people suffering from pancreatic dysfunction and chronic changes in large-caliber vessels;
- pathogenetic mechanisms of the fifth type of hyperlipidemia are based on the violation of the processes of destruction and elimination of triglycerides from the body, coming from food in excess. The debut of the disease occurs during the adolescent period and manifests itself in dysfunction of the pancreas with the subsequent development of signs of pancreatitis .
Treatment of hyperlipidemia
Medical measures for any form of hyperlipidemia are aimed primarily at correcting the modifiable risk factors with the use of non-drug methods, as well as drug treatment of hyperlipidemia manifestations and prevention of possible complications.
The modification of lifestyle and the correction of eating behavior are of great importance in leveling the signs of hyperlipidemia. Modification of a way of life is nothing other than the elimination of factors contributing to the development and progression of pathology.
Prior to the application of specific medicinal drugs aimed at reducing the lipid profile, the patient should be persuaded to maintain a certain diet. The lipid-lowering diet for hyperlipidemia significantly reduces the risk of developing complications of the cardiovascular profile.
Medication correction of hyperlipidemic states is used both for treatment of patients with atherosclerotic manifestations, and for asymptomatic course of the disease. Drugs used for the purpose of lipid-lowering therapy are aimed at directly reducing the cholesterol index, mainly due to low-density lipoproteins (bile acid sequestrants and statins). The area of application of this group of drugs is the family type of hyperlipidemia.
To correct the elevated indices of triglycerides and very low density lipoproteins, medicinal preparations of the fibrate group, as well as nicotinic acid derivatives, are used. These drugs find their application in all forms of hyperlipidemia, as they contribute to the increase in high-density lipoprotein parameters, which are directly involved in preventing the development of atherosclerosis .
Statins are an antibacterial agent of a synthetic and microbiological origin, whose action is directed at suppressing the activity of enzymes catalyzing the processes of biosynthesis of cholesterol in the hepatic parenchyma. During the first week of taking statins, a stable concentration of the active substance in the blood is observed, however, the maximal positive effect of using the drug of this group is observed not earlier than in 6 weeks. When appointing a patient statin with a view to correcting the lipidogram, it should be borne in mind that after the withdrawal of the drug there is an increase in the cholesterol and its fractions.
In most cases, the drugs of this drug group are well tolerated by patients, but there are a number of conditions that are absolute contraindications to their use (infectious diseases in the acute period, lesions of the hepatic parenchyma accompanied by an increase in transaminases). The most commonly used atorvastatin in a minimum daily dosage of 20 mg and a gradual increase in the dose to 80 mg, under the systematic control of lipidogram and transaminase.
In a situation where the patient has contraindications to the use of statins, or as an additional hyperlipidemic therapy, preparations of the bile acid sequestrant group are used (Kolestipol in a therapeutic daily dosage of 16 g orally). Drugs in this group are not used in cases of marked increase in triglycerides, as well as in the manifestations of colitis with a tendency to constipation .
The increased content of triglycerides in the plasma is well amenable to correction by the method of using fibrates (Bezafibrate in a daily dose of 1000 mg), the action of which is aimed at stimulating the activity of lipoprotein lipase and increasing the oxidation of fatty acids in the hepatic parenchyma. The area of application of fibrates is the diagnosed third type of hyperlipidemia.
Derivatives of nicotinic acid are recommended to be used if necessary to reduce the level of triglycerides and total cholesterol. The maximum daily dosage of this group of drugs is 3 g. These drugs are not widely used in the treatment of patients with hyperlipidemia, since their administration is accompanied by the development of a number of adverse reactions in the form of hyperemia of the skin of the upper body and dyspeptic disorders.