What are lipids?
Lipoproteins (or lipids) are fats that circulate in your bloodstream. They include:
- LDL (low-density lipoprotein), considered "bad" cholesterol because it contributes to plaque buildup in your arteries (atherosclerosis), which is linked to a higher risk of heart attacks and strokes.
- HDL (high-density lipoprotein), the "good" cholesterol, helps remove cholesterol from the blood. It can prevent the buildup of fats and formation of plaque. The primary determinant of HDL is inherited, however, quitting smoking, weight loss and exercise can help increase HDL levels.
- Triglyceride is another type of fat in your bloodstream. They can be elevated in people who drink a lot of alcohol and eat foods high in cholesterol, saturated fats and trans fats. High triglyceride levels can also be caused by diabetes, hypothyroidism, and kidney or liver disease. There’s a link between triglycerides and heart disease, insulin resistance, diabetes and obesity. People with high triglycerides often have high LDL and low HDL levels.
What is cholesterol?
Cholesterol is a waxy substance your body uses to make cells, hormones and vitamin D. It is an essential part of brain and nerve cells, and bile that helps your body absorb fats and fat-soluble vitamins. Your body gets cholesterol from the food you eat and your liver. In fact, your liver produces all the cholesterol your body needs.
What are lipid disorders?
Lipid disorders can cause Atherosclerosis (plaque buildup in blood vessels), Dyslipidemia (cholesterol is too high) and Hypolipidemia (cholesterol is too low). More specific lipid disorders include:
- Familial Defective Apolipoprotein B-100, a common inherited disorder, causes high LDL cholesterol. It’s treated with cholesterol-lowering medication.
- Familial Dysbetalipoproteinemia, a common inherited disorder, causes high triglyceride or very low-density lipoprotein levels, and early vascular disease. It’s treated with medications, a better diet and more exercise.
- Familial Hypercholesterolemia is inherited and causes high LDL cholesterol levels at birth. Patients have a very high heart attack risk at an early age. It’s treated with statin medications if LDL is chronically high.
- Familial Hypertriglyceridemia, a common disorder, causes elevated triglycerides but normal LDL and HDL. It’s treated with dietary changes to lower sugar and fat, and more exercise.
- Familial HDL Deficiency, an inherited disorder, causes very low levels of HDL. A severe type is called Tangier disease. It is treated by managing the risk of early heart disease.
- Niemann-Pick disease is a group of inherited lipid storage diseases. Lipids accumulate in the brain, spleen, liver, lungs, and bone marrow at harmful levels. Symptoms can include lack of muscle tone and control, brain degeneration, stiff muscles, increased sensitivity to touch, difficulty swallowing, eye clouding and paralysis, learning problems, and enlarged liver and spleen.
- Farber’s Disease, also an inherited lipid storage disease, allows lipids to build up to harmful levels in the joints, tissues and central nervous system. The heart, liver and kidneys may also be affected. Usually starting in early infancy, symptoms include mental impairment, problems swallowing, swollen lymph nodes and joints, shortening of muscles and tendons, skin problems and vomiting. There is no treatment and most children die by age 2. A milder form of the disease increases lifespan to young adulthood.
- Acid Lipase Disease or deficiency is inherited. Caused when an enzyme needed to break down fats is either lacking or missing, it allows fats to build up to toxic levels. Wolman’s disease is one of the lipid deficiency diseases that is usually fatal by age 1. People with Cholesteryl Ester Storage disease can be treated with medication to help adrenal gland production, and may live into adulthood.
- Barth Syndrome, occurring mainly in males, is caused by a gene mutation that prevents production of an essential lipid. It can affect the heart muscle, cause low white blood cell count, and lead to higher infection risk, muscle weakness, delayed growth, fatigue, and physical disability. Careful monitoring of diet is the only treatment; except for antibiotics for infections and medications to stimulate white cell production. Early and accurate diagnosis is essential for survival.
- Fabry Disease, caused by a mutated gene, allows lipids to build up to harmful levels in the nervous and cardiovascular systems, eyes and kidneys. Symptoms usually begin in childhood and can include: burning sensations in the arms and legs that worsen with exercise or hot weather, raised skin blemishes, impaired blood circulation, higher risk of heart attack or stroke, enlarged heart, kidney impairment or failure, fever, and stomach problems. It can be treated with enzyme replacement and anti-platelet medications.
- Gangliosidoses are a group of inherited diseases caused by a deficiency of several proteins needed to break down lipids. Damage to the brain and nervous system can be permanent. No specific treatment exists for gangliosidosis. Anticonvulsants may help control seizures, along with proper nutrition, hydration and maintaining an open airway. Children usually die by age 3 of heart complications or pneumonia.
- Metabolic syndrome, also called insulin resistance or dyslipidemia syndrome, can occur when your triglycerides and insulin levels are high, and HDL is low. Patients often have high blood pressure and excess fat around the waist. Metabolism is how your body uses food to make energy. Enzymes are chemicals in your gut that metabolize food into sugars and acids -- your body’s fuel. The energy produced can be used immediately or stored in tissues. A lipid metabolic disorder causes a problem with the storage process.
- Gaucher disease and Tay-Sachs disease are inherited diseases caused by insufficient digestive enzymes that aren’t available to break down lipids. Or, the enzymes don’t function properly, keeping fats from being converted into energy. Both diseases cause a harmful amount of lipids to accumulate in the body. This can be deadly, because cells and tissues are damaged, especially in the brain, nervous system, liver, spleen and bone marrow. It prevents these organs from working properly. Newborn babies are given blood tests to screen for both diseases.
- Gaucher disease has three types:
- Type 1 is the most common and can occur at any age. While it does not affect the brain, it does cause the liver and spleen to enlarge, bone pain, easily broken bones, and lung and kidney problems.
- Type 2 causes severe brain damage in infants and most die before age 2.
- Type 3 causes liver and spleen enlargement, starting in childhood or adolescence. The brain is eventually affected. Gaucher disease is not curable but can be treated with medications and enzyme replacement. However, there are no good treatments for the brain damage in types 2 and 3.
- Tay-Sachs disease affects infants. They appear to be normal for a few months and then begin to decline mentally and physically. They become blind, deaf, unable to swallow, and develop muscle wasting and paralysis. There is no cure and children usually die by age 4.