Hyperlipidemia Type III: Causes, Symptoms & Treatment

Hyperlipidemia type III or familial dysbetalipoproteinemia is a genetic lipid metabolism disorder in which blood cholesterol and triglyceride levels are elevated. Hyperlipidemia type III is a significant risk factor for atherosclerosis, vascular occlusion, and coronary heart disease.

What is hyperlipidemia type III?

Hyperlipidemia type III is the name given to a rare, genetic lipid metabolism disorder in which there is an elevated concentration of certain lipoproteins in the serum. Due to a disturbed lipid metabolism, lipid breakdown is only possible to a limited extent, which is why in hyperlipidemia type III both cholesterol (hypercholesterolemia) and triglyceride levels (hypertriglyceridemia) are elevated (combined hyperlipidemia). This is referred to as type III hyperlipidemia if the blood levels of these lipid components are above 200 mg/dl. Hyperlipidemia type III is manifested externally by xanthomas, yellowish nodules on the skin caused by local lipid deposits. In addition, the increased lipoprotein concentration in the blood present in type III hyperlipidemia leads to atherosclerosis and coronary heart disease in the long term.

Causes

Hyperlipidemia type III is genetic and due to autosomal-dominant (less commonly autosomal-recessive) inherited damage to a protein known as apolipoprotein E. Apolipoprotein E, as a component of some lipoproteins, regulates the uptake of chylomicrons and VLDL remnants into the liver. Chylomicrons and VLDL remnants are mainly composed of triglycerides and cholesterol and regulate lipid transport from the liver to other organs. Due to the presence of an abnormal apolipoprotein E, this metabolic process is disturbed, so that the concentration of cholesterol and triglyceride in the blood is increased. These substances are deposited on the blood vessel walls and form arteriosclerotic plaques, which increasingly increase the risk of occlusive diseases, strokes, coronary heart disease. However, only about 4 percent of genetically predisposed individuals develop type III hyperlipidemia. Other, secondary factors such as estrogen deficiency, obesity (adiposity), excessive alcohol consumption, and hypothyroidism (underactive thyroid) and diabetes mellitus play a significant role in the manifestation of hyperlipidemia type III.

Symptoms, complaints, and signs

Type III hyperlipidemia is initially manifested by elevated blood lipid levels. Physically, this elevation is manifested, among other things, by the typical orange-yellow skin changes that increase as the disease progresses and are often accompanied by pallor and sunken eye sockets. They usually occur between the fingers, on the knees, elbows or on the buttocks and back. In individual cases, deposits also occur on the eyelids. The fatty deposits do not normally cause any further symptoms, but they can promote circulatory disorders. In any case, they are a warning sign that must be clarified by a doctor. If they are not treated, the cardiovascular system and the blood vessels may suffer. Possible consequences are heart attack, circulatory disorders in the brain and stroke. In the long term, peripheral arterial occlusive disease can develop, which manifests itself, among other things, through pain on movement, disturbances in wound healing and a general decrease in physical performance. Type III hyperlipidemia impairs many endogenous processes and increases the risk of various diseases. Acute symptoms usually do not occur, but patients often experience an increasing feeling of illness, usually associated with pain in the chest area and numbness in the fingers and toes.

Diagnosis and course

Hyperlipidemia type III is diagnosed by blood analysis, which determines the proportions of chylomicrons and very low-density lipoprotein (VLDL), and thus indirectly cholesterol and triglyceride, in serum. If the values are elevated, the diagnosis of hyperlipidemia type III is considered confirmed. In some cases, ultracentrifugation or lipoprotein electrophoresis is used to precisely quantify the individual lipoprotein components. In addition, the underlying genetic defect can be determined by genetic testing.If left untreated, hyperlipidemia type III can lead to serious vascular disease (atherosclerosis), coronary heart disease, and cardiac events. Usually, the course of hyperlipidemia type III can be positively influenced in the course of therapy.

Complications

Hyperlipidemia type III can lead to an increased risk of heart disease or vascular occlusion. In the worst case, this can cause the patient to die from the heart conditions. Fatty deposits are formed on the fingers, which usually turn yellowish and orange. These complaints often lead to depression and inferiority complexes, as these symptoms are considered unaesthetic. It is not uncommon for this to lead to teasing and bullying in children. Furthermore, the patient suffers from circulatory disorders, so that, for example, the extremities suffer from an undersupply of oxygen. This undersupply can lead to permanent and irreversible damage to the extremities and other regions of the body. In some cases, hyperlipidemia type III results in limited mobility and thus a decreased quality of life. In most cases, hyperlipidemia type III can be relatively well limited. Treatment is mainly with medication and does not lead to further complications. However, the affected person is dependent on a healthy lifestyle. With prompt and positive treatment, the patient’s life expectancy is not reduced by the disease.

When should one go to the doctor?

People who notice yellow-orange fatty deposits on their hands and fingers should see a doctor. The noticeable skin changes indicate a serious condition that needs to be investigated and treated if necessary. If it is type III hyperlipidemia, treatment is usually given immediately, as the condition can cause various complications if left untreated. Therefore, if familial dysbetalipoproteinemia is suspected, it should be seen by the family physician immediately. At the latest when xanthomas as well as signs of circulatory disorders appear, medical advice is needed. Damage to the extremities and other regions of the body must be clarified immediately. If psychological problems occur as a result of the aesthetic changes, psychological advice is required. The patient should also contact a nutritionist and work out an individual diet together. In principle, type III hyperlipidemia is easily treatable, provided it is detected at an early stage. Because the disease is genetic, individuals who have cases of hyperlipidemia in their family should have genetic testing done early.

Treatment and therapy

Hyperlipidemia type III is usually treated with medication and diet. In this context, therapeutic measures are primarily aimed at weight reduction by changing the diet to plant-based, unsaturated fats. The dietary measures only have a strong reducing effect on the triglyceride values, but not on the cholesterol values, since only 15 percent of cholesterol is absorbed with food. If necessary, combined or monotherapeutic lipid-lowering drugs (including colestipol, lovastatin, nicotinic acid, sitosterol, clofibric acid, omega fatty acids) and plasmapheresis are used to lower cholesterol levels. Lipid-lowering agents reduce elevated blood lipids via various mechanisms by inhibiting cholesterol or lipoprotein synthesis or by directly lowering cholesterol or triglycerides. In therapeutic plasmapheresis, the patient’s own plasma is separated from the blood, purified and the essential components are replaced by a substitution solution. In addition, regular physical activity and exercise are recommended for supportive reduction of cholesterol levels. Basically, the secondary factors involved in the manifestation of hyperlipidemia type III should be treated simultaneously. If underlying diseases such as diabetes mellitus or hypothyroidism have triggered the type III hyperlipidemia, more comprehensive therapeutic measures are required.

Outlook and Prognosis

Although hyperlipidemia type III is not curable because of its genetic condition, it is readily treatable. With long-term therapy and a healthy lifestyle, a good prognosis can be assumed. However, without treatment, there is a somewhat lower life expectancy than in the normal population.This is because severe arteriosclerosis develops as a consequence of hyperlipidemia type III, which can quickly lead to heart attacks, strokes, or arterial occlusive disease (shop window disease). It is also significant for the prognosis whether the gene mutation is autosomal recessive or autosomal dominant. In the case of autosomal recessive inheritance, preventive measures can still prevent the onset of the disease. This is different in the case of autosomal-dominant inheritance. With this gene mutation, the onset of the disease is inevitable. As a rule, hyperlipidemia type III is easily treatable with therapy. This can increase the life expectancy of those affected and bring it into line with the level in the normal population. Therapy consists of a combination of measures including drug treatment and lifestyle changes. The most important goal of therapy is to lower cholesterol levels, which, in addition to the administration of cholesterol-lowering drugs, includes such measures as weight loss in the case of obesity, plenty of exercise in fresh air, dietary changes, and abstinence from smoking and alcohol. This significantly reduces the risk of atherosclerosis and its secondary diseases.

Prevention

Direct preventive measures are limited in hyperlipidemia type III because the disease is genetic. However, avoidance of secondary factors can counteract the possible manifestation of hyperlipidemia type III. A low-calorie and low-fat diet, exercise, and limited alcohol and nicotine consumption are among the measures that can prevent a manifestation of hyperlipidemia type III.

Follow-up

In most cases of hyperlipidemia type III, follow-up measures are severely limited. Here, the focus is on early detection and treatment of the disease, which prevents further complications or further worsening of symptoms. Self-cure cannot occur with this disease, which means that untreated hyperlipidemia type III can, in the worst case, lead to a reduced life expectancy of the affected person. In most cases, a healthy lifestyle with a healthy diet has a very positive effect on the further course of this disease. This includes avoiding obesity and also not smoking or drinking alcohol. It is also not uncommon for medication to be taken. It is important to ensure that the medication is taken regularly and in the correct dosage in order to alleviate the symptoms properly. In case of ambiguity or questions, a doctor should always be contacted first. In some cases, hyperlipidemia type III also requires the help and support of the patient’s own family in order to properly alleviate the symptoms and possibly also prevent psychological upsets or depression. In this regard, contact with other patients of the disease can also be very useful.

This is what you can do yourself

Because hyperlipidemia type III is genetic, direct treatment of the disease is usually not possible. However, those affected can limit the symptoms and discomfort of the disease well by adopting a healthy lifestyle. In particular, a low-fat diet and sufficient exercise can have a positive effect on the disease. Furthermore, patients with hyperlipidemia type III should avoid tobacco or alcohol. If the patient suffers from overweight, this must be reduced in any case. Sports activities in groups or with friends can be very helpful. As a rule, patients are also dependent on taking medication. These should be taken regularly in order to limit cholesterol levels as well. Often, those affected also suffer from diabetes due to hyperlipidemia type III, so that this condition must also be treated. A healthy diet and a strict regimen also have a very positive effect on the course of the disease. To prevent further complications or circulatory disorders, patients should also participate in regular examinations. Blood tests in particular can provide important results.