What is Pediatric Dyslipidemia?
Cardiovascular disease, a condition affecting the heart and blood vessels, is a leading cause of death in the United States and other parts of the world. In fact, one-third of worldwide deaths are because of cardiovascular problems. Doctors have found that a condition leading to cardiovascular disease, atherosclerosis (accumulation of plaque in the arteries), can start from childhood. Dyslipidemia, expressing abnormal levels of fats in the blood, treated in childhood can reduce the risk of developing cardiovascular disease later in life. This piece of information is particularly relevant today given the increase in obesity rates.
Regular health check-ups can identify dyslipidemia. This condition might include high total cholesterol, an increase in low-density lipoprotein cholesterol (bad cholesterol) levels or triglycerides, and a decrease in high-density lipoprotein cholesterol (good cholesterol) levels.
Doctors identify these abnormalities using a lipid panel test. For accurate results, the patient shouldn’t eat anything 8-9 hours before the test. This test measures total cholesterol, HDL-C, and triglycerides directly. LDL-C is then calculated using these measurements. If triglyceride levels are too high (above 400 mg/dl), LDL-C has to be measured directly.
If the lipid panel’s results are abnormal, the test is repeated 2 weeks to 3 months later for confirmation.
There are different guidelines for screening dyslipidemia in children. Current guidelines suggest all children should be tested between the ages of 9 to 11, and again between 17 and 21. Screening during these ages is essential because LDL cholesterol levels can naturally decrease during puberty. Early detection is crucial as family histories may be unreliable, and an early diagnosis can improve overall health outcomes. For instance, familial hypercholesterolemia increases the risk of developing cardiovascular diseases. However, only 20% of these cases are diagnosed.
Moreover, selective screening is advised for children with certain risk factors. This includes children with a family history of high cholesterol levels or premature heart disease, and health conditions like obesity, diabetes, and hypertension.
Normal cholesterol values vary based on age and gender, and doctors use specific tables to determine if a child’s cholesterol levels fall within the normal, acceptable, or high range. These ranges are consistent with guidelines provided by the American Heart Association and the American Academy of Pediatrics.
What Causes Pediatric Dyslipidemia?
Dyslipidemias, or abnormal levels of lipids (fats) in the blood, can be due to primary and secondary causes.
Primary dyslipidemias are inherited disorders caused by genetic issues that affect the production, transportation, or breakdown of lipoproteins (proteins that carry fats around the body). These disorders can affect a single gene (monogenic) or multiple genes (polygenic), showing up typically during childhood. They can lead to different types of high blood lipid levels due to defects in various genes.
For example, Familial Hypercholesterolemia (FH) is a common lipid disorder in kids, caused by genetic issues that lead to high levels of LDL (low-density lipoprotein), or “bad cholesterol.” Some people with FH have only one faulty gene (heterozygous FH), while others have two (homozygous FH). Only about 20% of FH patients are diagnosed, and even fewer get proper treatment.
Familial Combined Hyperlipidemia (FCHL) is also a common inherited disorder that increases bad cholesterol and triglycerides (another type of fat) in the blood. Similarly, Familial Hypertriglyceridemia (FHTG) leads to high triglycerides, while Familial Chylomicronemia causes very high triglycerides that can trigger pancreas inflammation (pancreatitis).
Sitosterolemia, meanwhile, causes extremely high levels of plant sterols (plant-based compounds similar to cholesterol) and cholesterol due to a genetic inability to limit the absorption and promote biliary excretion of these sterols. Low HDL cholesterol, the so-called “good cholesterol,” can be seen in conditions like obesity and in certain inherited disorders.
Secondary dyslipidemias, on the other hand, aren’t inherited. They can be caused by external factors such as being overweight or obese, drinking alcohol, or taking certain medications. Other health conditions like underactive thyroid (hypothyroidism), diabetes, some kinds of liver diseases, and infectious diseases like HIV can also lead to secondary dyslipidemias.
Given these possible causes, the best way to manage dyslipidemia is to have a healthy diet and lifestyle, maintain a normal body weight, avoid excessive alcohol, identify and treat any underlying conditions, and take prescribed medicines when necessary.
Risk Factors and Frequency for Pediatric Dyslipidemia
According to the National Health and Nutrition Examination Survey (NHANES), about 20% of teenagers (between the ages of 12 to 19) suffer from lipid disorders. The situation becomes more critical in obese children where as many as 42% have mixed dyslipidemia, which is a type of lipid disorder. Statistics show how common individual dyslipidemia is among children:
- Decreased HDL (good cholesterol less than or equal to 40 gm/dl) – 12.1%
- Elevated TG (high triglycerides equal to or more than 130 mg/dl) – 10.2%
- Elevated TC (total cholesterol over 200 mg/dl) – 7.1%
- Elevated LDL-C (bad cholesterol more than 130 MG/DL) – 6.4%
- Elevated non HDL-C (cholesterols excluding HDL over 145 mg/dl) – 6.4%
Dyslipidemia can be because of several reasons like diet, body mass index (BMI), levels of physical activity, genes, medications, and other health conditions. The NHANES data suggests that children with a higher BMI are more likely to have dyslipidemia. It shows that only 14% of children with a normal weight have dyslipidemia, whereas it presents in 22% of overweight children (BMI above 85%), and in a significant 43% of children who are obese (BMI above 95%).
Signs and Symptoms of Pediatric Dyslipidemia
Dyslipidemia, or abnormal cholesterol levels, are typically symptom-free. So, diagnosing them would require a detailed personal and family history, and a physical exam.
In terms of personal history, doctors would need information about:
- Your diet, including consumption of simple sugars, processed foods, fats (both saturated and unsaturated), overall portion sizes, and daily calorie intake
- Physical activity levels
- Screen time
- Smoking and alcohol consumption
- Existing liver or kidney disease
- Evidence of hypothyroidism (an underactive thyroid) or diabetes
- Any other chronic medical condition
- Any medications you might be taking
- Previous instances of pancreatitis symptoms such as abdominal pain and vomiting
In terms of family history, doctors would need information about:
- Any family members with dyslipidemia at an early age
- Family history of statin use (medication to lower cholesterol)
- Instances of heart-related diseases, especially heart attacks in women under 65 and men under 55, strokes, coronary artery disease procedures, and sudden cardiac deaths
Physical examinations for dyslipidemia might include a thorough check of height, weight, body mass index (BMI), heart rate, and blood pressure. Other examinations might look for abnormal cholesterol build-ups in the skin and eyelids.
Such buildups might include:
- Tendon xanthomas, or cholesterol deposits in tendons (most commonly the Achilles tendon or hands)
- Planar xanthomas, or painful cholesterol deposits in the palms of hands and soles of feet
- Xanthelasma, or cholesterol deposits appearing as yellow plaques found on the inner eyelids
Other signs of high cholesterol include a white or grey ring around the cornea, known as corneal arcus, and signs of artery disease. Even though these signs are uncommon in children, it’s important to check for them. They do this by checking pulse in all four limbs, listening out for abnormal noises in the carotid artery and femoral artery, and checking for any heart murmur.
Testing for Pediatric Dyslipidemia
For a proper check on your cholesterol levels, your doctor will require you to undergo a fasting lipid profile. This test measures your total cholesterol, good cholesterol (HDL), bad cholesterol (LDL) and triglycerides (a type of fat in your blood). It’s usually done when you’ve not eaten for several hours, often overnight. If your first test shows elevated levels, your doctor will likely ask you to repeat the test to confirm the results.
A key point here is that your cholesterol results can be influenced by food intake. This is particularly true for triglycerides. Therefore, your doctor will compare at least two fasting samples taken weeks to months apart to confirm if you have high cholesterol and to decide about any necessary treatment.
Extra tests can also be done to examine potential secondary causes of high cholesterol. These can include hormonal imbalances such as hypothyroidism, liver or kidney diseases, diabetes or even pregnancy. Additionally, a test for a protein called Lipoprotein(a) can be performed, as elevated levels can increase your chance of developing heart disease.
There’s also the possibility of genetic testing. These tests can help identify specific genes that might be causing abnormal cholesterol levels. They are particularly useful in determining whether you have a disease like Familial Hypercholesterolemia (FH), which is an inherited condition that causes high cholesterol levels. FH can then be confirmed by checking for changes in several specific genes. Genetic testing is valuable because it can aid in both diagnosing the condition and in treatment decisions. It also allows close family members to be informed and checked for the condition.
For example, different genes are related to specific lipid disorders causing reduced good cholesterol (HDL), low bad cholesterol (LDL), or elevated fat levels (Increased TG). Therefore, testing these genes can provide a more comprehensive understanding of your cholesterol health.
Treatment Options for Pediatric Dyslipidemia
Dyslipidemia is a condition marked by abnormal levels of lipids (fats), like cholesterol, in the blood. Managing this condition in children over ten is critical as there is increased risk of early-onset heart disease when the child has dyslipidemia, especially if LDL-C (considered as “bad” cholesterol) is high. By addressing this risk in childhood, we can reduce the chance of heart disease and increase life expectancy.
The American Heart Association created a risk classification system for children. There are three categories – high risk, moderate risk, and at risk, based on different factors. High risk factors include severe obesity and diabetes. Moderate risk conditions could include having a family history of early heart disease. At risk factors include things like abnormal blood pressure measurements or having specific congenital heart conditions. It’s important to note that the term premature heart disease usually refers to heart conditions in male family members under 55 or female family members under 65.
The suggested treatment approaches are:
1. For those with high or moderate risk factors, plus two or more heart disease risk factors, lifestyle changes such as a healthy diet, weight loss, and regular exercise should be coupled with medication known as statin therapy. The aim is to get the LDL value below 100 mg/dl.
2. For those with moderate risk conditions and less than two heart disease risk factors, or for those who are at risk, improvements in diet and lifestyle are suggested first. If this isn’t successful, then the use of statin therapy should be considered with the goal of getting LDL less than 130 mg/dl.
If dietary and lifestyle changes are not successful in children over the age of 10 with no risk factors, statin therapy can be initiated. In this case, the goal is to have an LDL less than 190 mg/dl.
The decision to start medication for dyslipidemia should be based on the results of two separate blood tests that were taken while fasting and at least two weeks apart.
All patients with dyslipidemia should be advised about dietary and lifestyle changes. Speaking with a nutritionist can be extremely helpful. They might recommend the Cardiovascular Health Integrated Lifestyle Diet (CHILD-1), designed to lower LDL-C levels. This diet involves limiting the intake of saturated fats to less than 10% of daily calorie intake and reducing cholesterol consumption to less than 300 mg/day.
Dietary recommendations for children are based on their age. For instance, children aged between 2 and 10 years are recommended to have a diet comprising 25-30% of fats with saturated fats being 8-10% of daily calorie intake, with encouragement around high fiber intake and at least one hour of moderate to vigorous physical activity.
In addition to this, dietary supplements like plant sterols and stanols, which are found in fruits, vegetables, and nuts, can reduce LDL-C by 5-15%. Alternatively, adding a fiber supplement to your cereal could potentially reduce LDL-C by 7%.
Physical activity and a reduction in sedentary behavior can improve lipid profiles and reduce the risk of heart disease. Therefore, limiting screen time and promoting age-appropriate physical activity should be encouraged. Weight loss is also encouraged when BMI is over 85%, and all children and adolescents should be advised against smoking and secondhand exposure.
The primary approach for treating pediatric dyslipidemia is dietary and life-style intervention. Still, in many cases, this alone is insufficient for lowering LDL cholesterol, leading to the requirement for medical treatment such as statin therapy. Statins work by blocking the enzyme responsible for cholesterol synthesis in the liver cells which helps to reduce cholesterol in the blood.
Other medications include bile acid binding agents which lower cholesterol by binding with bile acids in the intestine, preventing their reabsorption. Another class of drugs, fibrates, are used for severe cases of high TG levels, they work by increasing the breakdown of TG and reducing its production in the liver, thus lowering TG and increasing HDL-C.
In some cases, other methods may be required to manage high cholesterol levels, such as apheresis which physically removes lipoproteins from the blood or the use of PCSK9 inhibitors which lower serum LDL levels and have been shown to reduce LDL cholesterol by 60-70%.
Remember, these treatments should only be initiated under the recommendation and supervision of a healthcare professional.
What else can Pediatric Dyslipidemia be?
Before starting medication for high cholesterol (primary dyslipidemia), doctors should first make sure the patient isn’t dealing with secondary causes of the condition. The most usual secondary cause identified is a high Body Mass Index (BMI), usually found in overweight or obese people.
Other possible secondary reasons for high cholesterol may include:
- Issues with the thyroid gland (hypothyroidism)
- Liver diseases
- Kidney diseases
- Diabetes
- Pregnancy
- Alcohol consumption
- Specific medications
What to expect with Pediatric Dyslipidemia
Research clearly shows a link between high fat levels in kids’ blood (known as pediatric dyslipidemia) and the start and seriousness of atherosclerosis – a disease where plaque builds up in arteries. Fat levels in a child’s blood during their later childhood and teenage years can often predict what those levels will be when they’re adults in their thirties and forties.
It’s useful to check for dyslipidemia in kids who have extra risk factors such as diabetes, obesity, and a family history of early-onset atherosclerosis.
For children with a condition called Familial Hypercholesterolemia (FH), there’s a 90% chance they’ll develop coronary artery disease in their lifetime. In these kids, doctors can detect changes in the function of the thin layer of cells that line the inside of their heart and blood vessels (endothelial function) and the thickness of the inner two layers of their carotid artery (carotid intima-media thickness). These changes are reliable signs of how the disease might progress in later life.
Because of this, it’s strongly recommended to detect and get dyslipidemia under control early to reduce the risk of heart-related issues in adulthood and decrease chances of illness and death.
Possible Complications When Diagnosed with Pediatric Dyslipidemia
The main concern with dyslipidemia, a condition where you have high levels of unhealthy fats in your blood, is that it can cause a disease called atherosclerosis. This disease involves the hardening and narrowing of your arteries and can lead to serious health problems, even death. If dyslipidemia isn’t handled properly, it can result in several issues such as peripheral arterial disease, heart disease (which can trigger heart attacks or sudden death), strokes, and high blood pressure. Extremely high levels of a certain type of fat, called triglycerides, can also cause inflammation of the pancreas, a condition known as pancreatitis.
Common Complications:
- Atherosclerosis (hardening and narrowing of the arteries)
- Peripheral arterial disease (problems with blood circulation)
- Coronary artery disease (which can lead to heart attacks or sudden death)
- Cerebrovascular accidents (also known as strokes)
- Hypertension (high blood pressure)
- Pancreatitis (caused by extremely high triglyceride levels)
Preventing Pediatric Dyslipidemia
If you have dyslipidemia, a condition that causes an imbalance of fats in your blood, it’s important that you understand the changes you can make in your diet and lifestyle, in addition to taking medication. Consulting with a nutritionist can be greatly helpful in understanding the specific dietary adjustments you need to make.
Ideas for changing your lifestyle might include getting more exercise, reducing time spent watching TV or using computers, quitting smoking, and lowering the amount of alcohol you drink. It’s key to understand the health problems that can occur if dyslipidemia isn’t managed properly. This is because dyslipidemia typically doesn’t cause any noticeable symptoms for most of its duration.
If you need to take medication, it’s important to discuss the potential risks and benefits with your doctor. You should be informed about potential side effects and understand that you’ll need to monitor health changes and take medication over a long period of time.
