What is a Lipoprotein?
Lipoproteins are circular particles composed of fat or lipids and proteins which are present in the bloodstream and travel to the cells throughout the body. The two types of lipids found in lipoproteins are cholesterol and triglycerides. The human body is capable of making various kinds of lipoproteins. The presence of high levels of lipoproteins though can cause harm to the heart. But some lipoproteins are also heart healthy having direct advantages for the heart.
Lipoproteins are substances that carry triglycerides and cholesterol to the cells in the body. The good cholesterol also called HDL removes the bad cholesterol or LDL which tries to clog arteries of the heart. The presence of a gene leads to high levels of lipoproteins which narrows arteries. The levels of lipoprotein can be measured by a lipid blood test. The high levels of cholesterol can be successfully treated by making alterations in lifestyle and using medicines like statins.
What are cholesterol and triglycerides?
Cholesterol and triglycerides are fats which move around in the blood. The body produces and uses these fats in different ways.
- Cholesterol---Cholesterol is made by liver. It can also be got by the food that we consume for eg, from meat or dairy products. This animal fat helps the body to make vitamin D and the hormones called estrogen, testosterone and cortisol. It also assists the body to build cells of the nervous system.
- Triglycerides---Triglycerides are made by the liver and intestines present in the digestive system. When you consume lot of fat and calories the body makes more triglycerides. And it stores the extra amount in the fat cells. These fat cells release the triglycerides in the stream of blood if the body requires energy.
Types of lipoproteins
There are 5 main types of lipoproteins which are:-
- High-density lipoprotein (HDL)-It is the 'good cholesterol'. It carries cholesterol back to the liver which is then flushed out of the body. The high levels of HDL reduce the risk of heart ailments.
- Low-density lipoprotein (LDL)-It is the obvious counterpart of HDL and is the 'bad cholesterol.' It increases the chances of coronary artery diseases, heart attacks and strokes. LDL transports cholesterol which gathers as plaque inside the blood vessels. The accumulation of plaque can make the blood vessels very narrow for the free flow of blood. This is a condition which is called Atherosclerosis.
- Very low-density lipoproteins (VLDL)-It is a different type of 'bad cholesterol'. VLDLs carry triglycerides and cholesterol to the tissues of the body.
- Intermediate-density lipoproteins (IDL)-It is created when the VLDLs give up the fatty acids present in them. Then they are either removed by the liver or converted into an LDL.
- Chylomicrons-These are very large particles that also carry triglycerides.
Who is Lipoprotein (a) or LP (a)?
Lipoprotein (a) or LP (a) is a kind of LDL or bad cholesterol. A second kind of protein called Apoliprotein or apo(a) sticks around in segments called kringles. Apoliprotein makes the particles of LDL stickier. So LP (a) builds up in the blood vessels which also increases the risk of cardiovascular issues. The problem of Atherosclerosis is increased by the presence of high levels of LP(a).
What is a lipid panel blood test?
A lipid blood test is done to measure the total amount of cholesterol in the blood. The test provides individual measurement of HDLs, LDLs, triglycerides and total cholesterol. A cholesterol test requires simple drawing of a blood sample which takes lesser than five minutes. To get the most accurate results you need to fast for 8 to 12 hours before giving this blood test. You may require to stop taking certain medicines before giving the test.
How is lipoprotein(a) tested?
In a standard practice schedule LP(a) levels are not tested. This can only be tested during a lipid blood test if your healthcare provider specifically mentions it. This test is typically ordered for those patients who have certain heart disease risk factors like:-
- A personal history of heart issues.
- A family history of heart issues, specially heart issues in a very young aged first degree relative.
- Very high LDL levels.
- Having risks for Familial Hypercholesterolemia which is an inherited condition that leads to high LDL levels.
Why do we get a lipid blood test done?
You cannot identify the symptoms of high cholesterol. So testing it is the best way to identify cholesterol issues which affect the heart and blood vessels.
The lipid blood tests are used by doctors for:-
- Screenings-This blood test may be a part of a routine physical examination. The test can tell accurately if you are susceptible to cardiovascular ailments. So if you know you are at a risk then you can take steps to prevent heart attacks, strokes and other such problems.
- Diagnosis-You can get a cholesterol blood test to know about conditions like Atherosclerosis.
- Monitoring-The tests can indicate if your level of cholesterol is deteriorating and needs further care and treatment or vice versa.
When to get a lipoprotein test done?
The issues of high lipoprotein and cholesterol levels start to bother more with growing age.
Normal range for lipoproteins
The labs measure cholesterol and lipoproteins in miligrams per decilitre(mg/dl). But the different laboratories can use differing techniques which means results from the same blood sample can vary from lab to lab. The healthy ranges for HDLs, LDLs, triglycerides and total cholesterol vary with age and sex. In general these levels are in the healthy range if you have no other risk factors:-
Total cholesterol:100-199 mg/dl for adults over 21 yrs old and 75-169 mg/dl for 20 yrs and younger.
HDL(good cholesterol):45 mg/dl or higher
LDL(bad cholesterol): Less than 100 mg/dl
Triglycerides: Less than 150 mg/dl
The VLDL levels can't be measured by a lipid blood test and there is no separate test for measuring it. The labs estimate VLDL levels by dividing the triglyceride numbers by five. A healthy VLDL level is less than 30 mg/dl. But these results can not be accurate if the triglyceride levels are very high.
What is the normal range for lipoprotein(a)?
The LP (a) levels are given in mg/dl or nmol/L(nanomoles per litre). A reading above 50 mg/dl or 75 nmol/L is high and increases the risks of atherosclerosis, strokes and heart attacks.
Risks of having high LDL(bad cholesterol)
Women post menopause and adults over 40 are more prone to having high LDL levels. But sometimes children too have cholesterol issues. With age the process of metabolism slows down and the liver is also not able to remove the bad cholesterol from the body. Race and ethnicity also have to play a role in the determination of high LDL levels. Asian Americans are more susceptible to high LDL levels and white people for cholesterol.
If you eat a diet high in calories, saturated fats and cholesterol or have health conditions like diabetes or kidney issues, have a family history of high cholesterol, take too much alcohol and smoke, take medications like corticosteroids and drugs for high blood pressure, HIV and AIDS or are obese then you are at a risk of having high LDL levels.
Treatment for high LDL
The people who are at a risk for strokes, heart attacks and other such dangerous issues due to high LDL levels then they need cholesterol-lowering drugs like statins, ezetimibe, PCSK9 inhibitors. Lifestyle and dietary changes can also be helpful.
What can be done to improve the Lipoprotein levels
The dietary and lifestyle changes can lower bad cholesterol(LDLs) and boost good cholesterol(HDLs). Some of the steps that can help in this regard are:-
- You need to be physically active for 30 minutes in a day or 150 minutes every week.
- You should eat a heart-healthy diet which is low in unhealthy fats and simple sugars (carbohydrates) and high in fibre.
- You should be able to manage high blood pressure and diabetes.
- You should get more sleep.
- You should keep a healthy weight.
- You should also find healthy ways to manage stress.
- You should reduce your alcohol consumption and quit smoking as nicotine raises LDL levels and lowers HDL levels.
Conclusion
Lipoproteins can be classified into different types. HDL is a 'good cholesterol' which helps the system get rid of LDL or the 'bad cholesterol' that blocks arteries. Lipoprotein levels are also affected by lifestyle patterns, diet and smoking habits.
No comments:
Post a Comment