Hyperlipidemia is one of the major preventable cardiovascular risk factors and refers to increased levels of lipids (fats), such as cholesterol and triglycerides, in the blood.
Although hyperlipidemia does not cause symptoms, it can significantly increase your risk of developing cardiovascular disease, including diseases of blood vessels supplying the heart (coronary artery disease), brain (cerebrovascular disease), and limbs (peripheral vascular disease). These conditions can, in turn, lead to chest pain, heart attacks, strokes, and other problems. Because of these risks, treatment is often recommended for people with hyperlipidemia.
OTHER RISK FACTORS FOR CARDIOVASCULAR DISEASE
In addition to hyperlipidemia, there are a number of other factors that increase the risk of cardiovascular disease and its complications:
- Diabetes mellitus, type 1 and 2
- Hypertension (people with hypertension include those with a blood pressure at or above 140/90 and those who use blood pressure medication
- Kidney disease
- Cigarette smoking
- Family history of coronary disease at a young age in a parent or sibling (young, in this case, means younger than 55 years for men and younger than 65 years for women)
- Gender: Men have a higher risk of cardiovascular disease than women at every age
- Age: There is an increased risk of cardiovascular disease with increasing age
TYPES OF LIPIDS
The term lipids include cholesterol and triglycerides. There are many different types of lipid (also called lipoproteins). Blood tests can measure the level of your lipoproteins. The standard lipid blood tests include a measurement of total cholesterol, LDL (low-density lipoproteins) and HDL (high-density lipoproteins), and triglycerides.
Total cholesterol — High total cholesterol levels can increase your risk for cardiovascular disease. However, decisions about when to treat high cholesterol are usually based upon the level of LDL or HDL cholesterol, rather than the level of total cholesterol.
- A total cholesterol level of less than 200 mg/dL (5.17 mmol/L) is normal.
- Total cholesterol levels of 200 to 239 mg/dL (5.17 to 6.18 mmol/L) is borderline high.
- Total cholesterol levels greater than or equal to 240 mg/dL (6.21 mmol/L) is high
LDL cholesterol — Some healthcare providers make decisions about how to treat lipids based on the low-density lipoprotein (LDL) cholesterol (sometimes called “bad cholesterol”). Higher LDL cholesterol levels increase your risk of cardiovascular disease. If your health care provider uses this strategy, your goal LDL cholesterol will depend on several factors, including any history of cardiovascular disease and your risk of developing cardiovascular disease in the future. People at higher risk are often assigned a lower LDL cholesterol goal.
Triglycerides — High triglyceride levels are also associated with an increased risk of cardiovascular disease, although this association is not typically important once other risk factors are taken into account. Triglyceride levels are divided as follows:
- Normal – less than 150 mg/dL (1.69 mmol/L)
- Borderline high – 150 to 199 mg/dL (1.69 to 2.25 mmol/L)
- High – 200 to 499 mg/dL (2.25 to 5.63 mmol/L)
- Very high – greater than 500 mg/dL (5.65 mmol/L)
HDL cholesterol — Not all cholesterol, however, is bad. Elevated levels of HDL cholesterol actually lower the risk of cardiovascular disease. A level greater than or equal to 60 mg/dL or 1.55 mmol/L is excellent, while levels of HDL cholesterol less than 40 mg/dL or 1.03 mmol/L are lower than desired. There are no treatments for raising HDL cholesterol that has been proven to reduce the risk of heart attacks and strokes.
WHEN SHOULD I HAVE MY CHOLESTEROL LEVEL TESTED?
Lipid screening should start at age 35 in men without other risk factors for coronary artery disease and at age 20 to 35 in men with risk factors. These include men with:
- A family history of heart disease in a close male relative younger than age 50 or a close female relative younger than age 60
- A family history of high cholesterol
- A personal history of multiple coronary disease risk factors (e.g. smoking, high blood pressure).
Screening should include total cholesterol and HDL-cholesterol levels and can be measured anytime (with or without fasting).
WHO NEEDS TREATMENT FOR HIGH CHOLESTEROL?
The decision to start lipid-lowering treatment is made on a case-by-case basis. Healthcare providers consider current lipid levels, the presence or absence of cardiovascular disease (CVD), and other risk factors for CVD.
Several large trials have demonstrated that aggressive lipid lowering is beneficial in people with coronary heart disease. Many healthcare providers recommend treating all patients with CVD with high-dose statin therapy. People who have a heart attack (myocardial infarction or MI) are started on cholesterol-lowering medication while in the hospital and are advised to make lifestyle changes, regardless of their low-density lipoprotein (LDL) cholesterol level. In addition to simply placing a patient on statin therapy, some healthcare providers recommend that lipid-lowering treatment achieve specific goals in patients with known CVD:
- A target LDL cholesterol level below 70 to 80 mg/dL (1.81 to 2.07 mmol/L) is recommended for people who have CVD and have multiple major risk factors (eg, people with diabetes or who smoke).
- A target LDL cholesterol level less than 100 mg/dL (2.59 mmol/L) is recommended for people who have CVD but do not have any additional risk factors. Lifestyle changes, as well as nonstatin medications, may be recommended when LDL cholesterol levels are higher than 100 mg/dL (2.59 mmol/L).
People without a history of CVD also appear to benefit from lipid-lowering therapy, although the treatments are not as aggressive as in patients with CVD. There are also other special groups of disorders that can increase a person’s risk for cardiovascular diseases. These disorders include:
Hypertriglyceridemia — High triglycerides have not generally been thought to pose the same risk of CHD as LDL cholesterol. However, healthcare providers often recommend treatment for people with elevated triglyceride levels if they:
- Have very high levels (>500 to 1000 mg/dL or 5.65 to 11.3 mmol/L)
- Also, have high LDL cholesterol or low HDL cholesterol levels
- Have a strong family history of CHD
- Have other risk factors for CHD
Diabetes mellitus — People with diabetes (type 1 or 2) are at high risk of heart disease. Thus, an LDL level below 100 mg/dL(2.59 mmol/L) is recommended for many people with diabetes.
HIGH CHOLESTEROL TREATMENT OPTIONS
Lipid levels can be lowered with lifestyle changes, medications, or a combination of these approaches. In certain cases, a healthcare provider will recommend a trial of lifestyle changes before recommending a medication. The best approach for you will depend on your individual situation, including your lipid levels, health conditions, risk factors, medications, and lifestyle.
- Lifestyle changes — All patients with high low-density lipoprotein (LDL) cholesterol should try to make some changes in their day-to-day habits, by reducing total and saturated fat in the diet, losing weight (if overweight or obese), performing aerobic exercise, and eating a diet rich in fruits and vegetables.
- Medications — There are many medications available to help lower elevated levels of LDL cholesterol and triglycerides, but only a few for increasing HDL cholesterol.
- Statins — Statins are among the most powerful drugs for lowering LDL cholesterol and are the most effective drugs for prevention of coronary heart disease, heart attack, stroke, and death. Statins include lovastatin, pravastatin, simvastatin, fluvastatin, atorvastatin, and rosuvastatin. Statin is usually recommended to use at bedtime.
- Ezetimibe — Ezetimibe impairs the body’s ability to absorb cholesterol from food as well as cholesterol that the body produces internally. It lowers LDL cholesterol levels and has relatively few side effects.
- PCSK9 inhibitors — PCSK9 inhibitors are a newer class of drugs that lower LDL cholesterol levels. Drugs in this class also lower levels of other lipoproteins, such as lipoprotein(a), that can cause the buildup of blood vessel plaques. The PCSK9 inhibitors include alirocumab and evolocumab, which are given by injection every two to four weeks.
- Fibrates — Fibrate medications (gemfibrozil, fenofibrate, and fenofibric acid) can lower triglyceride levels and raise HDL cholesterol levels.
- Fish oil — Oily fish, such as mackerel, herring, bluefish, sardines, salmon, and anchovies, contain two important fatty acids, called DHA and EPA. Eating a diet that includes one to two servings of oily fish per week can reduce triglyceride levels and reduce the risk of death from coronary heart disease. Fish oil supplements are believed to have the same benefit. A daily 1 gram fish oil supplement may be recommended if you do not eat enough fish.
STICKING WITH TREATMENT — The treatment of high cholesterol and/or triglycerides is a lifelong process. Although medications can rapidly lower your levels, it often takes 6 to 12 months before the effects of lifestyle modifications are noticeable. Once you have an effective treatment plan and you begin to see results, it is important to stick with the plan. Stopping treatment usually allows lipid levels to rise again.
Aster Speciality Clinic, International City