Hyperlipidemia

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. One in every two people in Europe and America has abnormal blood lipid levels. In Turkey, the prevalence of this disorder is 80%. High levels of blood lipids (cholesterol and triglycerides) are almost a prerequisite for this group of diseases.

In recent years, sedentary lifestyles and increased consumption of animal products have made disturbances in blood lipid levels more frequent and severe.

What is Hyperlipidemia?

Changes in blood fats, which we call hyperlipidemia, refer to deviations of different fat fractions in circulation from target ranges. Cardiovascular diseases, known as atherosclerosis, are the result of narrowing, blockage, and thickening of the arteries. Hyperlipidemia is defined as having low-density lipoprotein cholesterol (LDL-C) above 130 mg/dL, high-density lipoprotein cholesterol (HDL-C) below 40 mg/dL, or triglycerides (TG) above 200 mg/dL.

What are the Risk Factors for Hyperlipidemia?

While many risks are identified for cardiovascular diseases, the following factors account for 80% of the risk:

– Hyperlipidemia,

– Smoking,

– Hypertension,

– Obesity,

– Genetics.

What is the Frequency of Familial Hypercholesterolemia?

It is not correct to assume that hyperlipidemia is solely due to lifestyle factors. The most common disease inherited with autosomal dominant inheritance worldwide is familial hypercholesterolemia. This is a form of genetic transmission. In these patients, cardiovascular diseases occur at an early age regardless of lifestyle.

Hyperlipidemia carries more significance than being just the main risk factor for CVDs. Without lipid fractions in the environment that pose a risk (often high LDL levels), atherosclerosis does not develop. All cardiovascular disease prevention guidelines published to date recommend calculating individuals’ risks; the higher the risk, the more intensive the measures needed. Therefore, treatments and preventive measures vary for individuals.

When Should Hyperlipidemia Screening Start and How Often Should it be Done?

Hyperlipidemia does not cause noticeable symptoms in patients when it is present. Symptoms develop in patients after the onset of cardiovascular disease (CVD). However, at this point, the disease is no longer preventable. Therefore, screening of the population can prevent the occurrence of CVD. The process of vascular damage begins long before clinical signs appear.

According to the latest hyperlipidemia guidelines:

– Adults aged 20 and over should undergo screening every 5 years.

– Middle-aged adults (men over 45 and women over 55) should be screened every 1-2 years.

– Adults aged 65 and over should be screened annually.

Apart from the general screening approach for the adult age group, different screening frequencies exist for special groups such as children, diabetes patients, those with chronic kidney failure, individuals with a family history of early-onset CVD, and elderly patients. The decision on which patients to screen and how often to follow up will be made by the physician according to the guidelines.

Which Tests Should be Done for Hyperlipidemia Screening?

The recommended tests include:

– LDL-C (low-density lipoprotein cholesterol)

– HDL-C (high-density lipoprotein cholesterol)

– TG (triglycerides).

If the TG level is above 400 mg/dL, it is suggested that non-HDL-C and Apo B measurements would provide more accurate information.

Intervention for Hyperlipidemia: Who, When, and How?

Over the years, many guidelines have been published to determine whether treatment is necessary for hyperlipidemia and which treatment should be chosen in which condition. Each published guideline recommends algorithms based on their own risk calculators. However, apart from minor differences, all guidelines agree on the main principles.

The first parameter used to determine the treatment target is LDL-C. Depending on the patient’s risk score, the LDL-C level is decisive for lifestyle changes and medication. Medication is planned by the patient’s physician, taking into account the patient’s other organ functions such as the liver and kidneys, other diseases such as diabetes and hypertension, and the risk of developing CVD. Various drug groups are used in medication.

Lifestyle & Dietary Changes: What are They?

A diet rich in fiber, phytosterols, and polyunsaturated fatty acids reduces the risk of CVD and mortality rates regardless of cholesterol levels. The balance of protein, fat, and carbohydrate intake in daily nutrition should be maintained. It has been proven that reducing one food group and increasing another has adverse effects. 

For example, 15-20% of daily nutrient intake should consist of protein. Recently popular low-carb, high-protein diets increase cardiovascular disease-related and non-cardiovascular disease-related mortality rates by increasing animal-derived fat and protein intake. Similarly, diets with high carbohydrate consumption have higher disease and mortality rates compared to balanced diets. 

A single dietary model is not suitable for all populations. However, the Mediterranean diet has been proven to reduce the incidence of CVD. Increasing the intake of fruits, vegetables, high-fiber grains, and legumes, reducing daily calorie intake, and avoiding processed foods, and reducing animal-derived foods are recommended for dietary plans. Heavy consumption of meat and meat products accelerates vascular damage. Saturated animal fats and high glycemic index foods should be eliminated from the diet.

Functional Foods: What are They?

Functional foods, which have scientifically proven effects on health in addition to their nutritional effects, are called functional foods. Some functional foods include phytosterols (plant-based oils), monacolin and yeast red rice, dietary fiber (derived from barley and oats), soy, policosanol, and berberine-containing foods.

Smoking and Alcohol Consumption:

Smoking and alcohol consumption disrupt vascular structure through different mechanisms, thereby facilitating the development of CVD to an advanced level in conjunction with hyperlipidemia. Smoking and alcohol cessation are recommended.

The Importance of Exercise in Hyperlipidemia:

Exercise is essential in hyperlipidemia. Aerobic exercises such as brisk walking, dancing, and cycling are particularly recommended. Depending on the patient’s age, muscle strength, and other diseases, aerobic exercises should start with 20-30 minutes per day and be performed 4-6 days a week, resulting in a significant reduction in CVD risk.

It should be noted that hyperlipidemia is a problem to be dealt with throughout life; therefore, it is important for dietary changes and exercise efforts to be sustainable.