Cholesterol - A Silent Killer / HYPERLIPIDEMIA

Hyperlipidemia is a group of metabolic abnormalities resulting in combinations of elevated serum cholesterol. 

Cholesterol (TC) and triglycerides (TG) are two of the major lipids in the body. 

They are transported through the bloodstream by lipoproteins. 

Lipoproteins are made up of a phospholipid and specific proteins called apoproteins or apo lipoproteins. 

There are five main classes of lipoproteins: 

• Chylomicrons 
• Very low density lipoproteins (VLDL-C) 
• Intermediate density lipoproteins (IDL-C) 
• Low density lipoproteins (LDL-C) 
• High density lipoproteins (HDL-C).

Etiology

Etiologic factors include chronic diseases, such as diabetes, hypothyroidism, nephrotic syndrome, liver disease, obesity, dietary intake; conditions, such as pregnancy and alcoholism; medications, such as beta-adrenergic blockers and diuretics.

Consequences

Atherosclerotic plaque formation in blood vessels.

Causes narrowing, possible ischemia, and may lead to thromboembolus formation.

Result in cardiovascular, cerebrovascular, and peripheral vascular disease.

Clinical Manifestations

• Usually asymptomatic until significant target organ damage is done 
• May be metabolic signs, such as corneal arcus, xanthoma, xanthelasma, pancreatitis 
• Chest pain, MI 
• Carotid bruit, transient ischemic attacks, stroke 
• Intermittent claudication, arterial occlusion of lower extremities, loss of pulses

Diagnostic Evaluation and Management

1. Fasting (9 to 12 hour fast) lipoprotein profile every 5 years for people ages 20 and older.
2. Assess the presence of clinical atherosclerotic disease that confers high risk for CHD events. (These atherosclerotic diseases are known as CHD risk equivalents; diabetes is also considered a CHD risk equivalent.) 
3. Decreased intake of saturated fat /cholesterol (< 7% of calories or < 200 mg/day) 
4. Therapeutic dietary options for improving lipid levels (plant stanols/sterols, 2 g/day, soluble fiber 10 to 25 g/day, omega-3 oils three times per week) 
5. Smoking cessation 
6. Weight reduction 
7. Increased physical activity 30 minutes of moderate activity 5 days per week or 20 minutes of vigorous activity 3 times per week 
8. Consider adding drug therapy if LDL exceeds levels 
9. Consider drug simultaneously with TLC for CHD and CHD equivalents. 
10. Consider adding drug to TLC after 3 months for other risk categories. 
11. Identify metabolic syndrome and treat, if present, after 3 months of TLC
12. Treat elevated TGs (150 or higher). 
13. Aim for LDL goal, intensify weight management, and increase physical activity. 
14. If TGs are 200 mg/dL or greater after LDL goal is reached, set secondary goal for non-HDL-C (total cholesterol minus HDL) 30 mg/dL higher than LDL goal. 
15. If TGs are 200 to 499 mg/dL after LDL goal is reached, consider adding drug if needed to reach non-HDL goal (increase primary drug or add nicotinic acid or fibrate). 
16. If TGs are 500 mg/dL or greater, first lower TGs to prevent pancreatitis. 
17. Very low-fat diet (15% or fewer calories from fat) 
18. Weight management and physical activity 
19. Fibrate or nicotinic acid 
20. When TGs are less than 500 mg/dL, return to LDL-lowering therapy 
21. Treat low HDL (< 40 mg/dL) by aiming for LDL goal, intensifying weight management, increasing physical activity, achieving non-HDL goal and, possibly, adding nicotinic acid or fibrate.

Complications

Disability from MI, stroke, and lower extremity ischemia.

Nursing Interventions and Patient Education
Teach diet basics and obtain nutritional consult.

Teach patient to engage in exercise.

Engage patient in smoking-cessation program.

Tell patients that for every 1% increase in HDL-C there is a 2% to 3% increase in risk for CHD.

Explain goal of recommended cholesterol levels. Encourage patients to keep a log of lipid results.

Encourage follow-up laboratory work repeat lipoprotein analysis and liver function test monitoring every 3 months for those on HMG-CoA reductase inhibitors.

Teach patient taking bile acid sequestrants not to take other medications for 1 hour before or 2 hours after, because it prevents absorption of many medications.

For more information on hyperlipidemia and TLC, refer to AHA: http://www.americanheart.org, or The National Heart, Lung, and Blood Institute diseases and conditions index: http://www.nhlbi.nih.gov/health/dci.