A lipid metabolism disorder occurs when the fat content of the blood exceeds normal levels. This applies to both elevated cholesterol and triglyceride levels. Elevated blood lipid levels lead to cardiovascular disorders in the medium to long term.
What is a lipid metabolism disorder?
Lipid metabolism disorders (dyslipidemias) refer to shifts in the composition of blood fats (lipids). There is usually an abnormal elevation of cholesterol or triglycerides, or both. Dyslipidemia is a collective term for several lipid metabolism disorders. Fats can be present in the blood both as esterified cholesterol and as triglyceride (normal fat). Although cholesterol is colloquially referred to as fat, it is not one of the fats. However, it is esterified with fatty acids, which are the main component of fat. Triglycerides are the fats that are also known as storage fats. Here glycerol is esterified with fatty acids. However, the entire group of substances belongs to the lipids. In order to make lipids transportable, they require transport proteins that combine with the lipids. So-called protein-lipid complexes are formed, which are called lipoproteins. Thus, lipoproteins include triglyceride-rich chylomicrons, very low-density lipoproteins (VLDL), low-density lipoproteins (LDL), and high-density lipoproteins (HDL).
Causes
Also critical to health effects is which protein-lipid complexes are elevated. For example, excessively high LDL contributes to the formation of atherosclerosis. An elevated HDL level, on the other hand, is actually beneficial. It lowers the risk of developing atherosclerosis. There are primary and secondary hyperlipoproteinemias. The primary forms of the disease are genetic, but usually only the predisposition is passed on. Whether or not the disease breaks out depends decisively on lifestyle. In particular, obesity, lack of exercise and an over-caloric diet contribute to an increase in blood lipid levels. Furthermore, this also worsens the ratio of LDL to HDL. Only very rarely is hyperlipoproteinemia genetically fixed in such a way that elevated blood lipid levels are already present at birth. The secondary form of lipid metabolism disorder is the consequence of an underlying disease such as type II diabetes mellitus, hypothyroidism, kidney disease or liver disease. It can also be caused by certain medications. Although primary and secondary dyslipidemia have different causes, their consequences are the same. Arteriosclerosis develops in the medium to long term.
Symptoms, complaints, and signs
In lipid metabolism disorders, there are primarily no symptoms. Long before the first symptoms appear, blood lipid levels may already be greatly elevated. Gradually, arteriosclerosis forms, which narrows or even clogs the blood vessels. The first symptoms may be difficulty breathing at low levels of exertion, chest tightness, pain in the right upper abdomen due to fatty liver tissue, or even inflammation of the pancreas. Later, there may be pain in the legs, heart attack, stroke or thrombosis. However, symptoms are not always to be expected even with very high blood lipid levels. Sudden cardiac death from seemingly perfect health is also possible. Signs that are often less noticed are so-called xanthomas and xanthelasmata. These are large or small skin nodules that contain foam cells loaded with cholesterol or fat. A gray-white ring around the cornea in young people is an indication of a hereditary lipometabolic disorder. Massively elevated hypertriglyceridemia often causes pancreatitis or reddish-yellow nodules on the buttocks.
Diagnosis
Because lipid disorders do not initially cause symptoms, they often go undiagnosed. Therefore, blood lipid levels should be determined every two years after the age of 35. Hyperlipoproteinemias are then easy to detect. The total cholesterol level, HDL and triglycerides are examined. From these values, the LDL value and the ratio of LDL to HDL can be calculated. More detailed testing is required if a severe lipid metabolism disorder is suspected. Genetic tests can determine which genetic changes lead to the elevated values. In the case of secondary lipid metabolism disorders, the physician looks for the underlying disease.
Complications
In most cases, a permanent dyslipidemia can have a negative effect on the heart and circulation. The risk for a heart attack increases in the affected person. In the worst case, death occurs after a heart attack. The patient usually does not feel any discomfort initially and can only detect it by being overweight. If the dyslipidemia is advanced, the patient may experience respiratory symptoms. This occurs even with the slightest exertion. Physical activities or sports are no longer possible for the patient. In some cases, sudden death may occur. Treatment in most cases is a strict diet and a healthy lifestyle. There are no complications and the lipometabolic disorder can be controlled relatively well. If the diet is followed, the dyslipidemia also does not recur. In severe cases, a so-called blood washing is performed. If the lipometabolic disorder cannot be permanently controlled, the patient is permanently dependent on blood washing. This leads to considerable restrictions in everyday life, which can also have a negative effect on the psyche. Thus, many patents additionally suffer from depression and a diminished sense of life.
When should one go to the doctor?
Lipid metabolism disorders are usually not noticeable for a long time by any complaints. If the first symptoms appear, damage has usually already occurred to the vessel walls, which can trigger a heart attack or stroke if left untreated. At the first signs, such as tingling or numbness in the hands and feet, a tightness in the chest during exertion or pain in the legs when walking long distances, a doctor should be consulted immediately. Vision problems, dizziness, speech disorders or confusion may also be caused by a circulatory disorder due to elevated blood lipid levels. Small yellowish-brown nodules (xanthomas) on the ears, eyelids, wrists, ankles and buttocks may indicate a congenital lipometabolic disorder. Such skin changes should be clarified by a doctor, as should a white-yellow-gray ring around the cornea in the eye, which in young people is often caused by a disturbed lipometabolism. A visit to the doctor is also advisable in the case of prolonged pain in the right upper abdomen, which can be triggered by a fatty liver. Occasionally, a strong increase in triglycerides, which is usually genetically determined, makes itself felt through pancreatitis, which requires immediate medical treatment due to its strong symptoms with severe abdominal pain, nausea and fever. Even healthy people should have their blood lipid levels checked regularly – this is especially true if close family members suffer from a lipid metabolism disorder.
Treatment and therapy
Therapy consists first of all of changing the way of life. This involves changing the diet. The proportion of dietary fat in the diet should be less than 30 percent. Attention should also be paid to an adequate supply of essential unsaturated fatty acids. In obesity, the reduction of excess weight has absolute priority. In addition to dietary changes, physical activity should not be neglected. Smokers should give up smoking immediately. If, despite these conventional measures, blood lipid levels still do not fall, drug treatment offers a good chance of returning them to normal. Among the most important lipid-lowering drugs are statins. They inhibit the production of LDL in the liver. This can reduce cholesterol levels by up to 50 percent. However, the drugs only take effect after several weeks. Parallel to drug treatment, a low-fat diet should be maintained. If both lifestyle changes and drug treatment are unsuccessful, blood washing can be performed. This treatment is also called lipid apheresis. By means of this treatment, blood lipids are removed from the blood. As with dialysis, blood washing must be done for life.
Outlook and prognosis
In many cases, the prospect of recovery from a dyslipidemia is related to the patient’s health condition as well as his or her willingness to change existing lifestyle habits. People, with a high body weight or obesity need weight loss to alleviate the symptoms.Sufficient daily exercise, participation in sports activities and a change in diet are essential for a good prognosis. Diet and avoidance of harmful substance intake through alcohol and nicotine are necessary for the reduction of symptoms. If the current lifestyle is maintained, there may be no regression of the acquired disorder despite medical care. On the contrary, an increase of the complaints is to be assumed. In the further course of the disease, the organism’s functions fail, resulting in a life-threatening condition. With a heart attack or stroke, the patient is threatened with premature death or lifelong severe health impairments. Drug treatment reduces the intensity of existing symptoms. This supports the functioning of individual organs or systems. If a permanent change in lifestyle is made, there is a good chance of an improvement in health. If there is a relapse into old habits or further weight gain, the patient’s health will inevitably deteriorate. If regular check-ups are taken, it is possible to react to changes in time. This improves the prognosis considerably.
Prevention
Lipid metabolism disorders can usually be prevented very well. Only in extremely genetic forms is this not possible. The most important thing is a healthy lifestyle. This includes a balanced diet, plenty of physical exercise, not smoking and not drinking. Furthermore, attention should be paid to weight. Since stress also has an impact on both diet and metabolism, it should be avoided as much as possible.
Aftercare
Long-term follow-up is mandatory for all lipid disorders. Increasingly, lipidological competence centers and networks as well as special lipid outpatient clinics are to take over this task. Many hospitals take over further treatment and follow-up after referral by a general practitioner. This initially consists of regular monitoring of blood lipid levels and other relevant parameters. The hospitals and outpatient clinics specialize primarily in the treatment and follow-up of certain forms of lipid metabolism disorders. Referrals are usually made when intolerance to cholesterol-lowering drugs – so-called statins – has occurred. The clarification of genetic factors that may have promoted the existing lipometabolic disease also plays a role. During follow-up, it is checked whether there is an indication for the prescription of PCSK-9 inhibitors. Therapy must be monitored. In most cases, outpatient treatment of the dyslipidemia is possible, but sometimes hospitalization is necessary because the lipid metabolism threatens to derail. Follow-up is mainly concerned with severe cases such as familial hypercholesterolemia with LDL receptor defects, familial hypercholesterolemias with ligand defects or secondary hyperlipo-proteinemias with concomitant presence of diabetes mellitus. Follow-up must ensure that the patient is well controlled with medication. He should lose weight, change his diet, and behave in a more adapted manner overall. Exercise may also be part of the aftercare regimen.
What you can do yourself
Those who suffer from disorders of their fat metabolism can also influence them themselves by favoring a healthier lifestyle. For example, many sufferers exercise too little, prefer to drive instead of ride a bicycle, or avoid climbing stairs. Their diet is also often unhealthy, consisting mainly of fatty and sweet foods. One of the most important self-help measures for a lipometabolic disorder is the right diet. Exercise takes place much less in today’s daily life than in earlier years. In addition, more food is consumed than the body actually needs. In order to favorably influence the course of a lipometabolic disorder or to prevent the disease from developing in the first place, a diet consisting of plenty of dietary fiber is extremely important. Mediterranean cuisine with plenty of fish is particularly recommended. It also makes sense to eat psyllium and oat bran. These high-fiber foods should be consumed regularly. It is also important to watch out for hidden fats in the diet.These are mostly found in convenience foods, meat, sweets, baked goods and whole milk products. It is also helpful to avoid alcoholic beverages, because this lowers the number of triglycerides. The same applies to the consumption of cigarettes. Thus, stopping smoking leads to an increase in the positive HDL cholesterol value. Regular exercise also plays an important role. Thus, it helps to reduce excess weight and provides an increase in HDL cholesterol.