Dyslipidemia

What is Dyslipidemia?

Lipids, like cholesterol or triglycerides, are substances absorbed from your gut and carried around the body within protein containers called lipoproteins. These lipids serve various roles like providing energy, producing steroids, or forming bile acid. Key players in these actions include cholesterol, low-density lipoprotein (LDL), triglycerides, and high-density lipoprotein (HDL). When an imbalance occurs, from either natural or lifestyle causes, a condition called dyslipidemia might result, leading to abnormal fat levels in the blood, increasing heart disease risk.

Lipids primarily include LDL cholesterol, HDL cholesterol, and triglycerides. Dyslipidemia has two forms: primary and secondary. Primary dyslipidemia is inherited and comes from changes in genes affecting lipid metabolism. Secondary dyslipidemia is acquired and is due to lifestyle factors or medical conditions that change lipid levels. Dyslipidemia commonly takes three forms:

• High LDL cholesterol, also known as “bad” cholesterol, can form blockages in the arteries, reducing blood flow.
• Low HDL cholesterol, or “good” cholesterol, helps remove LDL from the blood, protecting against artery disease.
• High triglycerides are kept in fat cells and used as energy when necessary. However, high triglycerides can also add to blockage formation and inflammation in the arteries.

Total cholesterol takes into account LDL, HDL, and half of the triglyceride level. High total cholesterol might indicate an increased risk of heart disease and stroke.

Dyslipidemia typically doesn’t cause symptoms but can be found with a blood test that measures lipid levels. The best lipid level can change based on age, gender, and other risk factors, but generally, these ranges are suggested:

• LDL cholesterol: less than 100 mg/dL
• HDL cholesterol: more than 40 mg/dL for men and more than 50 mg/dL for women
• Triglycerides: less than 150 mg/dL
• Total cholesterol: less than 200 mg/dL

The treatment method for dyslipidemia depends on the type, severity, presence of other risk factors like diabetes, high blood pressure, obesity, or smoking. The main goal is to lower LDL cholesterol, raise HDL cholesterol, and lower triglycerides.

Preventing dyslipidemia can reduce heart disease risk and improve life quality. Strategies involve:

• Regular screening, especially for those with a family history or other risk factors. How often and what type of screening partly depends on age, gender, and overall health, but generally, adults should have a lipid profile test every 4 to 6 years, and children and adolescents every 2 years.
• Fostering healthy habits e.g., a balanced diet with fruits, vegetables, whole grains, lean proteins, and healthy fats like omega-3 fatty acids found in fish, nuts, and seeds. Avoid foods high in cholesterol, saturated fats, trans fats, sugars, and salt. If feasible, do physical activity for at least 150 minutes per week. Keeping a healthy weight and body mass index, quitting smoking, and limiting alcohol intake are also advised.

Other health conditions like diabetes, high blood pressure, low thyroid hormone levels, chronic kidney disease, or liver disease can change lipid levels or increase heart disease risk. So, it’s important to take any prescribed medications correctly.

What Causes Dyslipidemia?

Dyslipidemia is a condition that affects the way your body processes fats or lipids. It can be caused by a mix of factors including your genes, environment, and lifestyle. Understanding what causes this imbalance in fats is vital to prevent and treat it properly. There are two main categories of dyslipidemia based on causes: primary and secondary.

Primary dyslipidemia is caused by changes in your genes that mess up how your body breaks down or uses fats. These may affect how fats are carried in your bloodstream, leading to an increase or decrease in fats and raising the risk of heart disease. For instance, familial hypercholesterolemia is a form of primary dyslipidemia where a problem in a specific gene causes a type of fat (LDL cholesterol) to pile up in your bloodstream, leading to heart disease. Other examples of primary dyslipidemia include familial hypertriglyceridemia, familial combined hyperlipidemia, and familial dysbetalipoproteinemia. The occurrence of these conditions can vary greatly depending on ethnic backgrounds and other groups.

Secondary dyslipidemia, on the other hand, is caused by situations or health conditions that affect the fat levels in your body. Unlike primary dyslipidemia, it can often be reversed or improved by addressing the cause. Examples of scenarios leading to secondary dyslipidemia include lack of physical activity, unhealthy diet, excess weight, diabetes, and more. According to a US study, about 28% of new patients referred to a lipid clinic had one or more causes of secondary dyslipidemia, with excessive alcohol intake and uncontrolled diabetes being the main culprits.

Various health conditions can result in secondary dyslipidemia. For instance, obesity can lead to high triglycerides, a type of fat. Diabetes can make the body resistant to insulin, leading to disruptions in fat processing. Hypothyroidism slows down the liver’s ability to clear LDL cholesterol and triglycerides from your bloodstream. Kidney disease can impair the breakdown of specific fats raising the triglyceride and LDL cholesterol levels. Liver disease can mess up the transport and disposal of cholesterol and triglycerides from the liver.

Smoking and alcohol abuse can also cause dyslipidemia, with smoking leading to low good cholesterol levels and alcohol to high triglyceride levels. Certain medications such as corticosteroids and beta-blockers can also disturb the metabolism of fats in the body, leading to either high or low cholesterol and triglyceride levels depending on the type and dose of the drug.

Risk Factors and Frequency for Dyslipidemia

Dyslipidemia is a worldwide health issue affecting millions of people. Dyslipidemia increases the risk of heart disease, which is the top cause of death globally. The occurrence and effects of dyslipidemia can vary due to various factors such as region, age, gender, and ethnicity, as well as genetic and environmental influences. Globally, it’s believed that anywhere from 20% to 80% of adults have dyslipidemia. This wide range is due to differences in how dyslipidemia is defined and measured.

Unfortunately, many countries lack up-to-date information on dyslipidemia in different populations. Furthermore, the awareness and treatment of this condition are often insufficient. For instance, between 2005 and 2008, a third of U.S. adults over 20 years old had high LDL levels (often referred to as ‘bad cholesterol’). However, only half of these individuals received treatment, and only 33.2% had managed to control their LDL levels. The poorest control rates were among those without insurance, Mexican Americans, or those living in poverty.

The impact of dyslipidemia is hard to measure directly since the condition typically doesn’t show symptoms and often accompanies other risk factors like high blood pressure, diabetes, obesity, and smoking. However, research shows that reducing LDL cholesterol can significantly lower the risk of major vascular events. Additionally, treatment like statins can decrease the risk of death due to heart disease or stroke. Dyslipidemia also places a significant financial burden on healthcare systems due to the increased costs of care and loss of productivity. For example, a U.S. study estimated that dyslipidemia cost about $34.4 billion in 2006, with almost $20 billion being direct medical costs.

Dyslipidemia affects men and women differently, with women generally having better cholesterol levels than men until menopause. However, women tend to have less access to adequate screening, diagnosis, and treatment compared to men, and they tend to do worse after cardiovascular events. It’s also increasingly prevalent among children and teenagers, particularly in developed countries, due to rising obesity rates and unhealthy lifestyles. This is a significant concern, as childhood dyslipidemia can carry on into adulthood, leading to premature heart disease.

Preventing and managing dyslipidemia is essential to reduce the global impact of heart disease. We must improve the awareness, treatment, and control of dyslipidemia across different populations and environments.

Signs and Symptoms of Dyslipidemia

Dyslipidemia is a medical condition that often goes unnoticed because it develops silently. It is crucial to understand its signs and symptoms in order to intervene promptly and prevent complications. Routine tests for lipids, specifically in individuals at high risk, are key to early detection and effective treatment. Health professionals take into account a patient’s wider health context, like family history and risk factors, to tailor suitable interventions and lessen the impact of cardiovascular diseases linked to dyslipidemia. A patient’s lifestyle choices, like smoking and diet details, can also be significant. Information on past medical conditions is vital to identify the relevant treatment, with the emphasis on prevention, before and after, if the patient needs to start statin therapy. Moreover, family history is essential to identify a genetic cholesterol disorder.

In some cases, individuals with severe or untreated dyslipidemia may show signs and symptoms related to complications such as clogged arteries, heart disease, peripheral artery disease, stroke, and heart failure.

• Xanthomas: These are yellow patches visible on skin areas like the eyelids, palms or tendons, indicating high cholesterol or fat levels in the blood.
• Arcus senilis: This is a gray or white ring around the eye’s cornea due to cholesterol depositing on the corneal edge. It is more common in the elderly but can also occur in younger people with dyslipidemia.
• Lipemia retinalis: This condition turns the retinal vessels milky due to high blood fat levels. It is a rare but could cause blurry vision and might indicate severe hypertriglyceridemia.
• Lower limb ischemia: This is a common symptom of peripheral artery disease, causing pain or cramping in the legs during physical activities due to blocked or narrow arteries. It can indicate high levels of LDL cholesterol or fats in the blood.
• Angina: This is a common symptom of coronary artery disease, occurs when the heart requires more oxygen, possibly during physical or emotional stress. It may indicate high levels of LDL cholesterol or fats in the blood.
• Transient ischemic attacks and strokes: Dyslipidemia increases the risk for a sudden disruption of blood flow in the brain due to a clot or bleeding originated from weakened blood vessel walls. Symptoms may include sudden weakness, slurred speech, or visual disturbances.

Testing for Dyslipidemia

Dyslipidemia is a significant risk factor for heart disease, and it’s important to diagnose it accurately. The primary way to check for dyslipidemia is through a fasting lipid panel. This test measures your total cholesterol, LDL (bad cholesterol), HDL (good cholesterol), and triglycerides (a type of fat in your blood). There isn’t a collective agreement about the age one should start getting screened for dyslipidemia.

There are different sets of guidelines for dyslipidemia screening:

• The National Cholesterol Education Program suggests that adults 20 years and older have a fasting lipid panel every five years.
• The US Preventive Services Task Force advises that men 35 years and older and women 45 years and older should have a lipid screening. Also, men and women who are between 20 and 35 years old and at high risk should also have a lipid screening. They recommend that younger adults with cardiovascular risk factors be screened too.
• The American Academy of Pediatrics advocates for screening in children and teenagers aged between 9 to 11 years and 17 to 21 years for dyslipidemia. They also recommend selective screening for those aged 2 to 8 years and 12 to 16 years who have a family history of dyslipidemia or heart disease, or other risk factors such as obesity, diabetes, high blood pressure, or smoking.
• The American Heart Association and American College of Cardiology recommend regular lipid screening every 4 to 6 years for patients between 40 and 75 years old. High-risk individuals, like those with diabetes or a history of heart disease, may need more frequent checks.

The National Institute of Health and Clinical Excellence provides guidelines that include a comprehensive test called QRISK3, which estimates the 10-year risk of cardiovascular disease.

There are also set ranges to classify lipid levels.

• Total cholesterol: desirable is under 200, borderline high is 200-239, and high is 240 or higher.
• LDL cholesterol (bad cholesterol): optimal is under 100, near optimal/above optimal is 100-129, borderline high is 130-159, high is 160-189, and very high is 190 and above.
• HDL cholesterol (good cholesterol): low is under 40 for men and under 50 for women, while high is 60 and above.
• Triglycerides: normal is below 150, borderline high is 150-199, high is 200-499, and very high is 500 and above.

Dyslipidemia is categorized into five different levels based on the Frederickson phenotype, determined by the level and type of lipid abnormalities present.

Treatment Options for Dyslipidemia

Managing high cholesterol levels usually starts with changes in lifestyle. This could include altering your diet, becoming more physically active, managing your weight, and quitting smoking.

Changing your diet could involve eating less saturated and trans fats, cholesterol, and refined carbohydrates, while increasing the intake of unsaturated fats, fiber, plant sterols, and antioxidants. Healthy diets for managing high cholesterol are the Mediterranean diet, the Dietary Approaches to Stop Hypertension diet, or the Therapeutic Lifestyle Changes diet. All of these diets can help lower bad cholesterol levels, boost good cholesterol levels, and reduce blood pressure, inflammation, and oxidative stress.

Becoming more physically active can help enhance your blood lipid profile (the amounts of different types of fats in your blood), lower your blood pressure, enhance insulin sensitivity, and promote weight loss. The American Heart Association recommends that adults aim for at least 150 minutes of moderate-intensity aerobic exercise, 75 minutes of vigorous-intensity aerobic exercise per week, or a combination of both. They also recommend that adults should perform muscle-strengthening exercises at least twice a week, which involve all major muscle groups.

Weight management can also improve your lipid profile, lower blood pressure, and reduce the risk of diabetes and metabolic syndrome. It involves achieving and maintaining a healthy body weight, which is defined as a body mass index of 18.5 to 24.9. For people with high cholesterol who are overweight, the aim should be for a gradual and sustained weight loss of 5% to 10% of their initial body weight over 6 to 12 months.

Quitting smoking can improve the lipid profile, lower blood pressure, and reduce risk of heart and other chronic diseases.

Medication can also be used as a treatment for high cholesterol. The first choice treatment is usually statins. These are prescribed based on patients’ ages and the severity of their condition. Statins work by reducing the amount of cholesterol your body produces.

For patients for whom statins aren’t effective enough, other medications may be used in addition. One such medication is ezetimibe, which prevents the body from absorbing cholesterol. There are also drugs that target a protein called PCSK9, which controls the level of a certain type of cholesterol in your blood. PCSK9 inhibitors lower levels of harmful cholesterol in your blood. A newer drug, inclisiran, interferes with the production of PCSK9 and can be beneficial for patients who are intolerant of other cholesterol-lowering medications. Another drug, icosapent ethyl, has been approved to reduce risk in patients with high triglycerides in addition to maximal statin therapy. Bempedoic acid is another drug that reduces cholesterol levels by inhibiting a certain process in the body that increases cholesterol levels.

Other drugs may be used as well, but they have not been shown to reduce heart disease risk. These include bile acid sequestrants, which help to rid the body of cholesterol, fibric acid derivatives that increase good cholesterol and reduce triglycerides, and niacin which increases good cholesterol and reduces bad cholesterol.

Different guidelines are available that provide recommendations and targets for the drug treatment of high cholesterol, such as those by the U.S. Department of Veterans Affairs and Department of Defense, the European Society of Cardiology and European Atherosclerosis Society, the Canadian Cardiovascular Society, and the American College of Cardiology and American Heart Association. The specific targets and first line treatment options depend on the specific guideline.

What else can Dyslipidemia be?

When trying to figure out what might be causing specific symptoms, doctors might consider several possible conditions. These could include:

• Nephrotic syndrome (a kidney disorder causing the body to excrete too much protein in the urine)
• Biliary obstruction (blockage in the tubes that carry bile from the liver to the gallbladder and small intestine)
• Hypothyroidism (a condition in which the thyroid gland doesn’t produce enough thyroid hormones)
• Pregnancy
• Usage of certain medications like oral estrogens, glucocorticoids, tamoxifen (a breast cancer medication), or thiazides (a type of diuretic)

Remember, it takes careful examination and testing by a healthcare professional to narrow down and confirm the exact cause of the symptoms.

What to expect with Dyslipidemia

The outlook for dyslipidemia, or abnormal cholesterol levels, depends on various factors. These include the type and severity of the lipid (fat) disorder, the presence of other elements increasing the risk of heart disease, adherence to lifestyle changes and medication, and the occurrence of complications.

Some types of dyslipidemia are more severe and need more rigorous treatments than others. For instance, a type of dyslipidemia called familial hypercholesterolemia, which is a genetic condition causing extremely high levels of ‘bad’ LDL cholesterol, elevates the risk of early and serious heart-related issues. People with this disease usually have to start taking medication such as statins, ezetimibe, or PCSK9 inhibitors as soon as possible, and may also need other treatments.

On the other hand, other types of dyslipidemia are affected by environmental or lifestyle factors, like diet, obesity, lack of physical activity, smoking, alcohol use, or use of certain medicines. Improvements in these factors with healthier lifestyle choices can help manage these forms of dyslipidemia.

Also, certain dyslipidemias are linked to other medical conditions, like diabetes, hypothyroidism, kidney disease, liver disease, or pancreatitis. In these cases, treating the underlying condition and managing any complications is the key to managing the cholesterol imbalance.

Possible Complications When Diagnosed with Dyslipidemia

The main concern with dyslipidemia, which refers to unhealthy levels of fats in the blood, is that it can lead to heart disease. The dangers of heart disease include sudden death, a heart attack, or a stroke. However, there is good news. Several studies show that effective dyslipidemia treatment, primarily using medicines called statins, can substantially lower the risk of death and heart-related problems.

Preventing Dyslipidemia

In simple terms, it’s crucial for patients to pay attention to certain lifestyle habits that can help maintain and reduce their cholesterol levels. These habits shouldn’t be restricted to but can include maintaining a healthy weight through a heart-friendly diet and regular exercise, as well as staying away from tobacco. Patients are also encouraged to talk with their doctors or other healthcare providers about the right time to begin health screenings or start treatments.

Some people may find natural supplements like herbs, red yeast extract, turmeric, curcumin, and garlic helpful for their cholesterol levels and general heart health. However, it’s important to remember that the scientific evidence supporting these benefits isn’t conclusive. These supplements might also have the potential to interact with some medicines or cause side effects, so it’s always best to talk to a healthcare provider before taking them.