The term fat metabolism disorders summarizes a number of diseases in which there is a pathological increase in one or more blood lipids.
We need fats - but in moderation
Blood lipids are essential to the human body as they perform a variety of tasks. They are not only energy suppliers for muscle and fat cells, but also involved in building certain hormones and Vitamins that are vital to the body.
However, if too much cholesterol and triglycerides are added to the blood, blood fats can also be harmful to the body and especially to the cardiovascular system.
In general, distinction is made between hypercholesterolaemias, hypertriglyceridemia and mixed hyperlipidaemias in lipid metabolism disorders. While in hypercholesterolemias, especially the LDL-cholesterol in the blood is increased, the triglycerides have increased in hypertriglyceridemias beyond the normal level. Mixed hyperlipidemias carry features of both of the above-mentioned disorders of lipid metabolism.
Always involved: nutrition and exercise
Lipid metabolism disorders can arise on the basis of a genetic predisposition or in the context of other underlying diseases. However, aspects of everyday life such as lack of exercise and an unhealthy diet or lifestyle are always involved in the development, which means that a genetic predisposition alone does not necessarily lead to an outbreak of the disease.
Especially for one reason, fat metabolism disorders are very treacherous: they cause no or very few symptoms, but have long-term but significant consequences on the vascular system. If increased blood lipid levels are detected late, secondary damage to the vessels may have already developed, which may, among other things, promote diseases such as heart attacks or strokes.
In this case, the diagnosis of a lipid metabolism disorder can be made relatively easy. Often a single blood sample is sufficient to detect elevated blood lipid levels and to provide the indication for therapy.
Change of life and medicines
The treatment of blood lipid elevations is based on different pillars. With only slightly elevated scores and no risk factors for the cardiovascular system, lifestyle changes are often enough to get the fat metabolism disorder under control.
In already known diseases, which can also lead to damage to the vascular system or at very high blood lipid levels or an unsuccessful therapeutic trial without drugs, a drug treatment is started. There is a whole range of preparations to choose from, which must be selected according to the type and amount of the altered blood lipids.
Lipid metabolism: What is good for which fats
Human body cells require blood lipids for a variety of functions. However, as they can not be self-sufficient by the body, blood fats must be ingested with food and brought via the blood to the particular site of use. The two most important blood lipids are cholesterol derivatives and triglycerides.
They have different tasks:
- Cholesterols are not fats in the true sense, but fat accompanying substances. They have a whole series of vital functions: on the one hand, they are energy suppliers for muscle and fat cells and involved in building the cell walls of each cell; On the other hand, they are needed to produce sex hormones and vitamins (especially vitamin D) as well as bile acids.
- Triglycerides are the actual blood lipids. They are the most important sources of energy for the development of fat and muscle cells.
Shuttle service for the fats
Dietary fats such as triglycerides and cholesterol must first pass through the blood to their place of determination. For this purpose, they are taken in the intestine via certain transporters and bound in the blood to so-called lipoproteins. Lipoproteins are transport proteins to which the blood lipids are bound and then distributed in the body.
Depending on the function, the following lipoproteins are distinguished:
- Chylomicrons: Triglycerides and cholesterols taken from the diet via the intestine are bound to chylomicrons and transported from there to the liver and to muscle and fat cells.
- LDL: LDL, together with HDL, is one of the major transport proteins for cholesterol. LDL has the function of transporting the cholesterol that has arrived or is produced in the liver to muscle and fat cells as well as providing it to the immune system. LDL is sometimes referred to as "bad" blood fat, as it can, if the concentrations in the blood rise too high, deposit on the vessel walls and can cause lasting damage.
- HDL: HDL takes the opposite route of the LDL. It ensures the return of excess cholesterol to the liver, where it is mostly processed into bile acids and excreted via the bile and intestines. Since HDL removes excess cholesterol from the body, it is also referred to as "good" blood fat, from which too little rather than too much circulates in the blood.
- VLDL: VLDL has a similar function to LDL as it transports triglycerides and cholesterol from the liver to the site of use. However, it is only responsible for the blood lipids produced in the liver.
Basics of fat metabolism
Definition and classification
Lipid metabolism disorders are a group of disorders that increase one or more blood lipid levels. In particular, it is distinguished which lipoproteins are increased in the plasma and whether this increase is hereditary (primary lipid metabolism disorder) or in another underlying disease such as diabetes mellitus, hypothyroidism, in stress or as a result of excessive alcohol consumption has occurred (secondary lipid metabolism disorder).
In general, primary forms tend to increase cholesterol levels in the blood, while secondary ones tend to increase triglycerides.
Increase of single or all fats
The most common disorders of lipid metabolism are:
- mixed hyperlipidemias
Hypercholesterolemias are characterized by an increase in total cholesterol in the blood plasma with a proportionately high concentration of LDL cholesterol, while the triglycerides are in the normal range.
In hypertriglyceridemia there is an increase in triglyceride levels, which is often associated with a decrease in HDL cholesterol levels.
As the name suggests, mixed hyperlipidaemias increase blood fat levels. The most common form of mixed hyperlipidemia is familial combined hyperlipidemia, which is genetic. It is typically associated with a concomitant increase in blood LDL cholesterol and triglyceride levels and a positive family history of early CHD.
Genes, pre-existing conditions and lifestyle
The exact causes that lead to a lipid metabolism disorder are not yet clear. It is certain that there is a genetic predisposition in primary forms that may cause an increase in blood lipid levels. For secondary forms, however, pre-existing conditions are the leading reason why blood lipid levels increase.
However, neither a genetic predisposition nor a previous disease are solely responsible for the development of a lipid metabolism disorder. Rather, additional influencing factors must be added that increase the risk of developing the disease.
These include in detail:
- Diet: Diet is a central aspect of the disease genesis of lipid metabolism disorders. Especially saturated fatty acids, which are mainly found in animal fats, can lead to a direct increase in cholesterol. By contrast, unsaturated fatty acids have a positive effect on cholesterol levels, leading to a reduction in LDL. Excessive consumption of coffee can also be bad for cholesterol, as the caffeine contained in it causes a kind of stress reaction in the body that stimulates the body's production of cholesterol as an energy source for the muscles.
- Movement: Regular physical activity, on the other hand, has a positive effect on blood lipid levels in two respects. On the one hand, sport leads to a reduction of superfluous triglycerides; On the other hand, there is an increase in HDL cholesterol, which is responsible for the removal of cholesterol from the blood.
- Gender: The blood lipid levels make the gender difference clearly noticeable. In men, cholesterol levels increase more with age than with women. At the same time they have a lower proportion of HDL cholesterol in the blood. In addition, the female estrogen protects the men from calcification before menopause.
- Age: Age also plays a major role in the development of lipid metabolism disorders. In early adulthood, there is often a marked increase in LDL cholesterol, followed by increasing numbers over the years.
More information here:
Causes of lipid metabolism disorders
Lipid metabolism disorders are particularly treacherous because they run for a long time without symptoms. Often, changes in blood lipids are detected by a routine check or incidental finding. Only late, it comes to complications that accompany symptoms.
The consequences of a lipid metabolism disorder include:
- Liver fatty tissue, which may lead to right upper abdominal pain
- repeated inflammation of the pancreas
- nodular fat deposits under the skin of hands and wrists as well as on the foot bones, buttocks or eyelids
- greyish-yellow opacification ring of the cornea
- Fat deposits on blood vessels of the fundus, which can lead to a reduction of visual performance
- Tingling and numbness in feet and hands
- Pain in the legs already after shorter walking distances
As part of the check-up is recommended for this reason from the 35th Age of the statutory health insurance, a review of blood lipids by the family doctor.
To diagnose a lipid metabolism disorder, your attending physician will first have a detailed interview (anamnesis) with you to find out if there are already known lipid metabolism disorders within your family. He will also give you blood and examine it for specific parameters.
Blood collection: please sober!
In order to obtain an accurate statement about your baseline blood fat levels, the first blood sample should be taken on an empty stomach or 12 hours after the last meal. At intervals of 14 days to 6 weeks, blood samples can be repeated if no drug therapy has been initiated.
For significantly elevated triglyceride levels, alcohol should not be consumed for at least one more week, and additional blood should be taken after this waiting period, as too much alcohol can lead to a transient increase in triglyceride concentration.
The results of your blood test are considered as "normal" if the following values are met:
- Total cholesterol <200 mg / dL (5.16 mmol / L)
- LDL cholesterol <150 mg / dL (1.7 mmol / L)
- HDL cholesterol> 40 mg / dL (1.03 mmol / L)
- Triglycerides <150 mg / dl (1.7 mmol / l)
The indication for triglycerides is only valid if there is no positive family history of coronary heart disease. This means that no relative of the first degree may be ill with CHD. If the family history is positive, the lipoprotein (a) is usually determined in addition. If this is also increased, individual therapy is started with therapy even at lower triglyceride concentrations.
Hypercholesterolemia is characterized by an increase in the total cholesterol concentration with a concomitant increase in LDL cholesterol. The diagnosis of hypercholesterolemia is not only based on the increase in individual values, but also takes into account the presence of other risk factors for the development of atherosclerosis.
These are among others:
- Diabetes mellitus
- arterial hypertension
- smoking history
Consequently, the diagnosis of hypercholesterolemia can be made if:
- a risk factor for arteriosclerosis and an increase in total cholesterol to 200-300 mg / dl (5.16-7.74 mmol / l) with a simultaneous increase in the LDL cholesterol content to> 160 mg / dl (4.13 mmol / l ) are present.
- there are two or more risk factors, the total cholesterol at 200-300 mg / dL (5.16-7.74 mmol / L) and the proportion of LDL cholesterol is> 130 mg / dL (3.35 mmol / L) ,
- a coronary heart disease or diabetes mellitus with simultaneous increase in total cholesterol to> 200 mg / dl (5.16 mmol / l) and the LDL cholesterol content to> 100 mg / dl (2.58 mmol / l).
By definition, the blood levels for triglycerides are always below 150 mg / dl (1.7 mmol / l) for hypercholesterolemia.
In the context of hypertriglyceridemia there is usually an increase in the triglyceride concentration to values between 150 and 500 mg / dl (1.7-5.65 mmol / l) and a reduced concentration of HDL cholesterol, although this is not obligatory. Unlike hypercholesterolemia, isolated hypertriglyceridemia does not present an increased risk of arteriosclerosis unless there are other risk factors for vascular calcification.
In rare cases, however, hypertriglyceridemia can lead to triglyceride levels of> 1000 mg / dL (> 11.29 mmol / L), which in the broadest sense leads to thickening of the blood and may result in disturbances of microcirculation.This in turn can cause severe sequelae such as strokes, heart attacks or acute inflammation of the pancreas.
Mixed hyperlipidemias are characterized by a concomitant increase in LDL cholesterol and triglyceride levels in the blood. By definition, there is also a positive family history of coronary heart disease (CHD), which means that at least one first-degree relative must be diagnosed with CHD.
With regard to concomitant or consequential diseases, further examinations may be of importance in the diagnosis in order to be able to better estimate the cardiovascular risk.
These include in detail:
- one-time or long-term blood pressure measurement
- Derivation of an ECG
- Measurement of blood sugar
- Calculating height and weight to calculate body mass index (BMI)
Read more about this topic here:
Important questions about diagnostics and examinations
Avoid consequential damage
The treatment of lipid metabolism disorders is very heterogeneous. In addition to the type of lipid metabolism disorder, the level of blood lipid levels and pre-existing conditions, which lead to an increased risk of arteriosclerosis, are crucial for the treatment pathway. The aim of any blood lipid lowering therapy, however, is the risk reduction for secondary diseases.
Treatment depending on the risk
In many cases, a so-called global risk is determined before the start of treatment, by means of which a target value for LDL cholesterol can be set. To determine the global risk, among other things, the following parameters are recorded and evaluated according to a risk score:
- family history
- Total cholesterol in the blood
- LDL cholesterol in the blood
- HDL cholesterol in the blood
- Diabetes mellitus
- smoking status
Since fat metabolism disorder is considered to be particularly dangerous if there are other factors that increase the risk of arteriosclerosis, treatment for lipid metabolism disorders also includes comprehensive advice on other diseases and risks that affect the vascular system.
1. Therapy goals
Depending on the form of the lipid metabolism disorder you suffer from and how high the blood lipid levels are, there are different target values of the individual lipoproteins:
Regardless of the lipid metabolism disorder, the German Society of Cardiologists recommends the following target values of blood lipids for all people suffering from CHD:
- LDL cholesterol <100 mg / dl
- HDL cholesterol> 40 mg / dl
- Triglycerides <200 mg / dl
Choice of therapy options
The therapeutic options for the treatment of lipid metabolism disorders are very diverse. It has generally been shown that lowering LDL cholesterol has beneficial effects on the risk of cardiovascular disease, and in particular CHD.
To reduce blood lipids different measures come into question. In addition to non-drug treatment strategies, there are a number of different drugs that are used in lipid metabolism disorders.
2. Non-drug measures
Non-drug treatment strategies or the consequent change of lifestyle are the beginning of every therapy. The success of diet change, exercise and stress reduction is very different. It depends not only on how consistently you manage to change your life, but also on the nature of the lipid metabolism disorder.
For hypercholesterolemia, the following measures are recommended in particular:
- a restriction of calorie intake to about 2000-2500 a day
- a reduction in the intake of dietary fats
- the replacement of saturated fatty acids by unsaturated
- the reduction of cholesterol intake to about 300 mg per day
- high-fiber diet instead of fast-absorbing sugars
In hypertriglyceridemia these treatment strategies are in the foreground:
- Consistent restriction of alcohol consumption
- high-fiber diet instead of fast-absorbing sugars
Slow but steady
The change in diet is not equivalent to a strict diet. Rather, it is the replacement of unfavorable foods with cheap ones, which in the long term can lead to a 20-60 mg / dl reduction in total cholesterol.
Specifically, this means that an individual total calorie count of 2000-2500 kcal per day should not be exceeded. Fats should account for no more than 30% of food intake, while proteins should account for 15-20% and carbohydrates should account for about 50-55% of daily intake. At 2000 kcal per day, this would be equivalent to about 280 grams of carbohydrates, 75 grams of protein, and 70 grams of fats.
Fat is not the same fat
But not all fats are the same. Saturated fatty acids, which are found mainly in animal fats such as meat, butter, egg or lard, increase LDL levels. By contrast, monounsaturated fatty acids such as rapeseed or olive oil as well as polyunsaturated fatty acids (contained in thistle, sunflower, corn, soy, linseed or white fish, for example) are able to lower LDL levels during HDL levels unaffected or even rising.
The least healthy are the so-called trans fatty acids, which arise when heating unsaturated fatty acids, so for example when frying chips or in the production of chips and ready-made pizzas. Trans fats not only increase LDL cholesterol, they also lower HDL, making them doubly unhealthy in a sense.
The question about the eggs
To summarize, a diet shift should aim to eat less meat and sausage, butter, eggs and fried foods such as chips and co., While increasing the proportion of sea fish, vegetables and fruits, vegetable oil and steamed foods.
Eggs are repeatedly the focus of discussion in lipid metabolism disorders. If you are healthy and eat a healthy diet, you do not have to worry about a daily breakfast egg either. However, if there is already an increase in blood lipids, a maximum of two eggs a week should be consumed.
The cornerstone of the diet: carbohydrates
Carbohydrates should account for approximately 55% of the daily calorie count. High-carbohydrate carbohydrates have a positive effect on blood lipid levels as they stimulate intestinal activity, shorten digestion time and thus contribute to a lower uptake of cholesterol from the intestine. Furthermore, they inhibit the production of cholesterol and the recovery of bile acids from the intestine via various mechanisms, which leads to an overall regulation of blood lipid levels.
The following carbohydrate carriers are particularly rich in fiber:
- Whole wheat pasta
- Brown rice
- Whole wheat and rye whole grain bread
On the other hand, light pasta and rice, but also white bread, are much lower fiber because fiber is in the shell of the grain and is lost in the process of producing light foods.
Here you will find further important information:
Questions about nutrition
b) exercise and stress management
Regular physical activity has a beneficial effect on blood lipid levels in two ways. On the one hand, the proportion of triglycerides in the blood is lowered, and on the other hand there is an increase in HDL cholesterol.
But also complications of a lipid metabolism disorder can be prevented by sports. Thus, the increased energy consumption in sports contributes to a weight loss and to a reduction of stress and tension states, but also to a healthier lifestyle, which in the long term has positive effects on the vascular status and can prevent, for example, heart attacks or strokes.
Physical activity should be used to control blood lipid levels at least three to four times a week for 30 minutes. The most suitable are endurance sports such as Nordic walking, jogging, swimming or cycling.
The drug therapy of lipid metabolism disorders is usually only started when a lifestyle change over three to six months could not improve blood lipid levels.
Particular attention is paid to the parameters of total and LDL cholesterol as well as HDL cholesterol and triglycerides, whereby different treatment principles are pursued. Depending on the form of the metabolic disorder and which concomitant diseases are present, a treatment is started at different times and treated with various medications.
The treatment of hypercholesterolemia is dependent on concomitant diseases affecting the cardiovascular system. Thus, hypercholesterolemia is diagnosed and treated in the following cases:
- if a risk factor for arteriosclerosis and an increase in total cholesterol to between 200 and 300 mg / dl (5.16-7.74 mmol / l) with a simultaneous increase in LDL cholesterol levels> 160mg / dl (<4.13 mmol / l) l) are present.
- if two or more risk factors persist, the total cholesterol at 200-300 mg / dl (5.16-7.74 mmol / l) and the level of LDL cholesterol increased to> 130 mg / dl (> 3.35 mmol / l) is.
- in the presence of coronary heart disease or diabetes mellitus with simultaneous increase in total cholesterol to> 200 mg / dl (> 5.16 mmol / l) and the LDL cholesterol level to> 100 mg / dl (> 2.58 mmol / l) ,
In the first place are statins
The drugs of first choice for the treatment of hypercholesterolemia are the statins. Statins are currently the drugs that are the most effective in lowering LDL levels.
A standard dose will typically reduce LDL cholesterol by up to 35-50%, while increasing the dose of statins up to twice the standard dose may increase the effect by as little as 6%, with side effects such as fatigue, fatigue, Muscle and limb pain as well as an increase of the liver values occur more frequently.
Among the most commonly administered statins in the context of hypercholesterolemia include:
- Atorvastatin (Sortis®, Atoris®)
- Simvastatin (Zocor®)
- Fluvastation (Cranoc®, Lescol®, Locol®)
- Pravastatin (Mevalotin, Pravagamma®, Pravalip®, Pravasin protect®)
- Rosuvastatin (Crestor®)
If statins alone are not enough
If the therapy goals set can not be achieved by statin monotherapy within 6 to 12 months after initiation of therapy, a combination of statins and a drug from another substance group is recommended. These can, when combined with statins, achieve a further reduction of LDL cholesterol levels by 20-30%.
The individual classes of medication include:
- Fibrates: Fibrates such as benzafibrate (Benzafibratum®) and fenofibrate (fenoglide®, Lipofen®, Procetofen®) in combination with statins have several effects on blood lipid levels. In addition to a further reduction in LDL cholesterol by 20%, they lead to an increase in HDL of up to 30% as well as a reduction of triglycerides by about half. For this reason, fibrates are particularly suitable for the treatment of mixed hyperlipidemias. However, a major disadvantage of fibrates is that they should not be taken as soon as kidney and liver disease or pregnancy persists. Furthermore, they increase the effect of some blood thinners and oral antidiabetics.
- Nicotinic acid: The nicotinic acids (niacin®) leads to the strongest increase in HDL cholesterol while reducing triglycerides among the drugs used to treat lipid metabolism disorders. Nicotinic acids are therefore used almost exclusively for the treatment of mixed hyperlipidemias. However, nicotine acids in the EU have not been on the market since 2013, as side effects such as itching, burning sensation, diarrhea, nausea, muscle aches and increased glucose tolerance have been reported during treatment, while cardiovascular benefits are uncertain could be detected.
- Exchange resins: Exchange resins such as cholestyramine (Lipocol®, Quantalan®, Vasosan®) and Colesevelam (Cholestagel®) bind bile acids in the intestine and lead to their excretion. Since, as a result, less bile acids can be reabsorbed and reused from the intestine, new bile acids must be formed from cholesterol. Consequently, LDL cholesterol decreases by 20-25% in the blood while increasing HDL cholesterol. The disadvantage of exchange resins is that certain drugs are also ingested more poorly from the intestine and should therefore only be taken to exchange resins at intervals of four hours. These include aspirin, digitalis, coumarins, thyroxine and certain statins.
- Cholesterol absorption inhibitors: Cholesterol uptake inhibitors such as ezetimibe (Ezeterol®) inhibit the direct absorption of cholesterol from the intestine. They are especially effective in combination with statins and are tolerated and therefore the most commonly used supplement from fatty acids in hypercholesterolemias.
Since primary hypertriglyceridemias can be exacerbated by alcohol consumption, absolute alcoholism is at the forefront of any treatment with the aim of lowering the triglyceride level to <150 mg / dL (<1.7 mmol / L).
In addition, there are always attempts at therapy with fibrates, nicotinic acid and fish oil preparations, to which, however, there are no convincing study data. For this reason, if there is hypertriglyceridemia, a strict change in lifestyle should be made, with the absolute renunciation of alcohol and a dietary change to Mediterranean diet.
c) Mixed hyperlipidemias
Mixed hyperlipidaemias as well as hypercholesterolemias are treated depending on the overall risk.
For example, there is a direct treatment indication in the following cases:
- <2 Risk factors: LDL cholesterol <160 mg / dL (<4.14 mmol / L); Triglyceride values <150 mg / dl (<1.70 mmol / l)
- ≥ 2 risk factors: LDL cholesterol <130 mg / dL (<3.35 mmol / L); Triglyceride values <150 mg / dl (<1.70 mmol / l)
- Presence of vascular disease such as myocardial infarction or diabetes mellitus: LDL cholesterol <100 mg / dL (<2.58 mmol / L); Triglyceride values <150 mg / dl (<1.70 mmol / l)
- after a heart attack and a vascular disease such as.heart attack or diabetes mellitus: LDL cholesterol <70 mg / dl (<1.80 mmol / l); Triglyceride values <150 mg / dl (<1.70 mmol / l)
In the foreground of the treatment of mixed hyperlipidemia is the lowering of LDL cholesterol to the desired target value. For this purpose, primarily statins are used, which can be combined with fibrates such as fenofibrate and benzafibrate or with nicotinic acid in greatly increased or uncontrollable triglycerides.
The treatment of lipid metabolism disorders is very complex and in many cases a case by case decision, because not everyone responds to the same extent to the medication and this does not tolerate equally well.
For any treatment path, however, drug therapy does not mean that you can do without diet and exercise. On the contrary, the success of a drug treatment is highly dependent on a consistent change in lifestyle.
Too much fat damages the vessels
The fat metabolism disorder is so dangerous because it causes no symptoms for a long time, but can lead to significant vascular damage and can affect the cardiovascular system enormously. Especially if, in addition to the fat metabolism disorder, there are other factors that have a detrimental effect on the vascular system, severe complications can occur at an early stage.
With each of the following influencing factors the danger for a consequential illness increases:
- insufficient movement
- wrong diet
- high blood pressure
- Diabetes mellitus
Heart attack, stroke & Co.
Secondary diseases, which can develop on the basis of a long-term existing lipid metabolism disorder, are thereby above all:
- coronary heart disease (CHD)
- Chest tightness (angina pectoris) & heart attack
- peripheral arterial disease (PAD)
- fatty liver
- Diseases of the pancreas
Particularly common among the consequences of increased blood lipids are diseases of the cardiovascular system. Roughly speaking, any increase in blood plasma LDL levels increases the risk of cardiovascular disease by approximately 10%. This rule of thumb alone makes it clear how important regular monitoring and treatment of elevated blood lipid levels is.
And a few tips to conclude:
Self-help with lipid metabolism disorders
Author: Lisa Wunsch
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