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Hyperlipidemia is a term employed to indicate increased
cholesterol and/or triglycerides (another fat in the blood). Hypercholesterolemia
(increased cholesterol) is a major risk factor for coronary artery disease (CAD). High
levels of low-density lipoprotein (LDL) cholesterol (the bad cholesterol) are the
main target for cholesterol-lowering therapy. Low levels of high-density lipoprotein (HDL)
cholesterol (the good cholesterol) and high levels of triglycerides (TG) are additional
risk factors for CAD. The benefit of treating hyperlipidemia has been demonstrated in many
studies.
Cholesterol Screening
A. Recommended for all adults older than age 20, every 5 years.
B. Measure total cholesterol and HDL (nonfasting testing is OK).
C. Total cholesterol levels are defined as follows:
1. Desirable: less than 200 mg/dl (5.2 mmol/liter)
2. Borderline: 200–239 mg/dl (5.2–6.2 mmol/liter)
3. High: greater than 240 mg/dl (6.2 mmol/liter)
D. HDL: desirable is greater than 35 mg/dl (0.9 mmol/liter)
Diagnosis of Increased Cholesterol
A. If total cholesterol is borderline or high or to monitor treatment, obtain a lipid
profile after a 12-hour fast.
B. LDL is calculated as follows (valid if TG less than 400 mg/dl): LDL = Total cholesterol
– HDL – (TG/5)
C. Document other CAD risk factors:
1. Nonmodifiable risks: age (men greater than 45, women greater than 55), family
history of premature CAD.
2. Modifiable risks: cigarette smoking, hypertension, diabetes, low HDL (less than 35
mg/dl).
3. Protective factor: HDL greater than 60 mg/dl.
D. Categorize for treatment based on LDL and risk factors:
1. LDL less than 100 mg/dl is the goal for people with established CAD.
2. LDL less than 130 mg/dl is the goal for people without CAD but with two or more risk
factors.
3. LDL less than 160 mg/dl is the goal for people without CAD and with fewer than two risk
factors.
Diagnosis of Increased Triglycerides
(hypertrygliceridemia)
A. Triglyceride levels are defined here:
1. Normal: less than 200 mg/dl (2.3 mmol/liter)
2. Borderline high: 200–400 mg/dl (2.3–4.5 mmol/liter)
3. High: 400–1000 mg/dl (4.5–11.3 mmol/liter)
4. Very high: greater than 1000 mg/dl (11.3 mmol/liter)
Treatment of Increased Cholesterol
A. Rule out and treat other causes of hyperlipidemia, i.e, type II diabetes,
hypothyroidism, nephrotic syndrome, chronic renal failure, alcoholism, anabolic steroids,
etc.
B. Diet modification is first-line therapy and should be tried for several months before
considering drug therapy. Weight loss and increased exercise are important components of
diet therapy.
C. Delay drug therapy in premenopausal women and young adult men with high LDL who are
otherwise at low risk for CAD.
D. Consider drug therapy in high-risk postmenopausal women and elderly people with high
LDL who are otherwise in good health.
Dietary Treatment (therapy) of Increased
Cholesterol
A. Healthy diet recommendations for the general public includes the following:
1. Reduce total fats to less than 30% of calories and saturated fats to less than 10% of
calories (limit meat to 6 oz/day, use lean cuts of beef and pork with fat trimmed, remove
skin from poultry, avoid fried foods and highly saturated oils such as palm or coconut,
use low-fat dairy products).
2. Reduce cholesterol to less than 300 mg/day (limit egg yolks to 4 per week, and avoid
organ meats).
3. Substitute monounsaturated fats into the diet (olive and canola oils are good sources).
4. Increase complex carbohydrates to 55–60% of calories (fresh fruit, vegetables, and
whole-grain products).
B. Water-soluble fiber in the diet or as a supplement can help to lower LDL. Sources
include oat bran, beans, fruit, and psyllium (Metamucil).
C. A more restricted diet may be tried with the assistance of a dietitian if cholesterol
control is inadequate and the patient is willing. Saturated fats are limited to 7% of
calories and cholesterol to 200 mg/day.
Drug Treatment of Increased Cholesterol
A. Primary lipid-lowering drug classes include nicotinic acid, bile acid sequestrants
(resins), and HMG-CoA reductase inhibitors (statins).
B. Consider addition of a primary drug if diet and exercise fail to lower LDL to goal
levels within 3–6 months. Encourage their use when LDL remains greater than 190 mg/dl
(4.9 mmol/liter) in people without risk factors, greater than 160 mg/dl in people with two
or more CAD risk factors, or 130 mg/dl in people with documented CAD.
C. If response to the first drug is inadequate, a drug from another class or a combination
of drugs from different classes may be tried. Low-dose resins used with nicotinic acid or
statins have been very safe and effective. Statins combined with nicotinic acid or
gemfibrozil may increase the risk of muscle damage.
Treatment of Increased Triglycerides
(hypertrygliceridemia)
A. Very high TG warrant therapy to reduce the risk of pancreatitis (inflammation of the
pancreas). Pancreatitis is a disease that can occur as a consequence of very high
triglycerides. Treatment of borderline or high TG to reduce CAD risk remains
controversial.
B. Therapy includes exercise, weight reduction, alcohol restriction, and treatment of
contributing causes. Niacin or gemfibrozil may be useful in resistant cases.
C. Primary therapy includes: nicotinic acid (niacin), Gemfibrozil (Lopid), and Probucol
(Lorelco). However, Probucol is not generally recommended.
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