Antilipemic Drugs: Lipid Management

Triglycerides and Cholesterol

• Lipids are water-insoluble fats in the blood that must bind to apolipoproteins, which are specialized lipid-carrying proteins.
• The liver is the major organ of lipid metabolism and cholesterol manufacture.
• Lipoprotein is a combination of triglyceride or cholesterol with apolipoprotein.
• Very-low-density lipoprotein (VLDL) is produced by the liver and transports endogenous lipids to the cells.
• Low-density lipoprotein (LDL) and high-density lipoprotein (HDL) are types of lipoproteins.
• HDL is responsible for "recycling" cholesterol and is known as "good cholesterol."

Cholesterol and Coronary Heart Disease Risk

• Low HDL levels are less than 40 mg/dL.
• Total cholesterol levels of 300 mg/dL are three to four times greater than in patients with levels less than 200 mg/dL.
• As cholesterol increases, so does the incidence of death from coronary heart disease.

Treatment Guidelines

• Antilipemic drugs are used to lower lipid levels as an adjunct to diet therapy.
• Drug choices should be based on the patient's specific lipid profile.
• Clinical atherosclerotic cardiovascular disease and LDL cholesterol ≥ 190mg/dL are factors in drug choice.
• Diabetics who are 40 to 75 years of age with LDL levels 70 to 189mg/dL and no evidence of CVD should use antilipemic drugs.
• Individuals with no evidence of CVD or diabetes but who have LDL levels, 70 to 189mg/dL and high risk factors for CVD development within 10 years should use antilipemic drugs.
• All reasonable non-drug means of controlling blood cholesterol levels (diet, exercise) should be tried for at least 6 months before drug therapy.

Antilipemics

• HMG-CoA reductase inhibitors (HMGs or statins)
• Bile acid sequestrants
• Niacin (vitamin B3 or nicotinic acid)
• Fibric acid derivatives (fibrates)
• Cholesterol absorption inhibitors (Zetia)
• Herbal medications

HMG-CoA Reductase Inhibitors (Statins)

• Statins are the most potent LDL reducers.
• Examples of statins include pravastatin (Pravachol), simvastatin (Zocor), atorvastatin (Lipitor), fluvastatin (Lescol), rosuvastatin (Crestor), and pitavastatin (Livalo).
• All statins are given orally, and with the evening meal.
• Baseline cholesterol (total, HDL, LDL), triglycerides, and renal and liver function tests should be monitored before and periodically during therapy.
• Results take 6-8 weeks before results are seen.

HMG-CoA Reductase Inhibitors: Action and Effects

• Statins inhibit HMG-CoA reductase, which is used by the liver to produce cholesterol.
• Lowers the rate of cholesterol production, they are a first-line drug therapy for hypercholesterolemia.
• Outcomes include reduced LDL levels, increased HDL levels, and reduced triglycerides.
• Mild, transient GI disturbances, rash, headache, myopathy (muscle pain), elevated liver enzymes, liver disease, and peripheral neuropathy are possible side effects.

HMG-CoA Reductase Inhibitors: Interactions

• Oral anticoagulants should not be taken with statins.
• Statins interact with erythromycin, antifungals, verapamil, diltiazem, HIV protease inhibitors, and amiodarone.
• Grapefruit juice may delay the metabolism of statins.

Bile Acid Sequestrants

• Bile acid sequestrants are considered second-line drugs and may be used with statins
• Examples include cholestyramine (Questran), colestipol hydrochloride (Colestid), and colesevelam (Welchol).
• Colesevelam (Welchol) is taken orally in tablet form with food and 8oz of water, and not with other medications.
• Cholestyramine (Questran) is supplied as a powder.

Bile Acid Sequestrants: Action and Effects

• Bile acid sequestrants prevent the reabsorption of bile acids from the small intestine.
• Bile acids are necessary for the absorption of cholesterol.
• Constipation, heartburn, nausea, belching, and bloating are side effects that get better over time.

Niacin (Nicotinic Acid)

• Niacin is vitamin B3.
• Niacin is effective and inexpensive, often combined with other lipid-lowering drugs.
• Niacin decreases triglycerides and total serum cholesterol.
• Niacin decreases LDL levels and increases HDL levels.

Niacin Action and Effects

• Niacin increases the activity of lipase, which breaks down lipids.
• Niacin reduces metabolism of cholesterol and triglycerides.
• Flushing (caused by histamine release), pruritus, GI distress, hyperglycemia, and hepatotoxicity are possible side effects.

Fibric Acid Derivatives (Fibrates)

• Gemfibrozil (Lopid) and fenofibrate (Tricor) are fibric acid derivatives.
• Outcomes include decreased triglyceride levels and increased HDL levels.

Fibric Acid Derivatives (Fibrates): Actions and Effects

• Fibric acid derivatives activate lipase to break down cholesterol.
• They suppress the release of free fatty acids from adipose tissue.
• They inhibit the synthesis of triglycerides in the liver.
• They increase secretion of cholesterol in the bile.
• Abdominal discomfort, diarrhea, nausea, blurred vision, headache, increased risk of gallstones, prolonged prothrombin time, and myopathy are possible side effects.

Fibric Acid Derivatives: Interactions

• Fibric acid derivatives interact with oral anticoagulants and statins.
• A risk for myositis, myalgias, and rhabdomyolysis increases when fibric acid derivatives are taken with statins.
• Laboratory test reactions include decreased hemoglobin levels, hematocrit value, and white blood cell count, as well as increased activated clotting time, lactate dehydrogenase level, and bilirubin level.

Cholesterol Absorption Inhibitor

• Ezetimibe (Zetia) inhibits cholesterol absorption.
• Cholesterol absorption inhibitors are often combined with statins.
• They are currently recommended only when patients have not responded to other therapies.
• Outcomes include decreased total cholesterol, LDL, and triglyceride levels, as well as increased HDL levels.

Cholesterol Absorption Inhibitor: Action and Effects

• Action is to inhibit absorption of cholesterol secreted in the bile and from food.
• Hepatitis and myopathy are possible effects.
• Contraindicated in patients who have mild to severe liver disorder.

Herbal Products: Omega-3 Fatty Acids

• Omega-3 fatty acids are herbal products used to reduce cholesterol.
• They may cause rash, belching, and allergic reactions.
• There are potential interactions with anticoagulant drugs.

Herbal Product: Garlic

• Garlic is an herbal product used as a lipid reducer.
• Adverse effects include dermatitis, vomiting, diarrhea, flatulence, and antiplatelet activity.
• It has possible interactions with warfarin and diazepam.
• It may enhance bleeding when taken with NSAIDs.

Herbal Product: Flax

• Both the seed and oil of the plant are used, and are used for hypercholesterolemia
• May cause diarrhea and allergic reactions
• Possible interactions: antidiabetic drugs, anticoagulant drugs

Nursing Implications

• Contraindications include biliary obstruction, liver dysfunction, and active liver disease.
• Obtain baseline liver function studies.
• Patients on long-term therapy may need supplemental fat-soluble vitamins (A, D, K).
• Take with meals to decrease GI upset.
• Powder forms must be taken with a liquid, mixed thoroughly but not stirred, and NEVER taken dry.
• Other medications should be taken 1 hour before or 4 to 6 hours after meals.
• To minimize adverse effects of niacin, start on a low initial dose and gradually increase it, and take with meals.
• Small doses of aspirin or NSAIDs may be taken 30 minutes before niacin to minimize cutaneous flushing.
• Inform patients that these drugs may take several weeks to show effectiveness.
• Instruct patients to report persistent GI upset, constipation, abnormal or unusual bleeding, and yellow discoloration of the skin.
• Monitor for adverse effects, including increased liver enzyme studies.
• Monitor for therapeutic effects to show reduced cholesterol and triglyceride levels

SDOH (Social Determinants of Health)

• 30 Tablets of Zocor without insurance will cost $195.65
• 30 Tablets, 40mg each of the generic lipitor costs ~$126.99 without insurance
• Questran - 1 Box, 60 packet each of the generic cholestyramine costs $148.99
• The out-of-pocket cost of a lipid panel can range from $200 to $843 without insurance and $19 with private insurance or Medicare