Introduction
Hyperlipidemia means abnormally high levels of fats (lipids) in the blood. These fats mainly include cholesterol and triglycerides. High lipid levels often come from unhealthy lifestyle choices such as a fatty diet, lack of exercise, and obesity, although some people inherit the condition.
High cholesterol is one of the biggest risk factors for heart disease, stroke, heart attack, and atherosclerosis. Globally, raised cholesterol contributes to millions of deaths every year.
Causes (Etiology)
- High-fat or sugary diet
- Obesity and lack of physical activity
- Diabetes mellitus
- Hypothyroidism
- Kidney and liver diseases
- Pregnancy
- Genetic factors
- Medications (e.g., protease inhibitors)
How it develops (Pathophysiology in simple words)
Excess calories, fats, and sugars in the diet get converted into triglycerides and stored in the body. The liver also makes cholesterol naturally. When the intake of fatty foods is high and physical activity is low, the body produces more lipids than needed, leading to hyperlipidemia.
Role of lipoproteins
- Chylomicrons: carry dietary fat from the intestine to the liver.
- LDL (“bad cholesterol”): carries cholesterol to body tissues; high levels cause plaque buildup in arteries.
- HDL (“good cholesterol”): removes cholesterol from tissues and takes it back to the liver.
- VLDL/IDL: other lipoproteins that promote atherosclerosis.
When LDL levels are high, cholesterol deposits in artery walls form “plaque.” Over time this leads to narrowing of arteries, reduced blood flow and risk of angina, MI, and stroke. HDL helps clean excess cholesterol, so low HDL increases risk.
Signs & Symptoms
Hyperlipidemia usually has no symptoms. The only way to detect it is through a blood test called a lipid profile.
Diagnosis
A lipid profile is done after 10–12 hours of fasting and includes:
- Total cholesterol
- LDL cholesterol
- HDL cholesterol
- Triglycerides
Treatment Overview
Treatment aims to reduce LDL, raise HDL, and lower triglycerides to prevent heart disease. Lifestyle modification is the first step, followed by medications when needed.
Non-pharmacological therapy
- Healthy diet low in saturated and trans fats
- More fiber, fruits, vegetables, and omega-3 fatty acids
- Regular exercise (minimum 150 minutes per week)
- Maintain healthy weight
- No smoking
- Limit alcohol
Pharmacological Therapy
1. Bile Acid–Binding Resins
These drugs bind bile acids in the intestine, preventing their reabsorption. Since the liver needs cholesterol to make new bile acids, it pulls LDL from the blood, reducing LDL levels.
Examples:
- Cholestyramine: 4–24 g/day
- Colestipol: 2–16 g/day
- Colesevelam: 6–7 tablets/day
2. Statins (HMG-CoA Reductase Inhibitors)
Statins block the enzyme responsible for cholesterol production in the liver. They are the most effective drugs for lowering LDL and also help raise HDL and reduce triglycerides.
Examples:
- Atorvastatin: 10–80 mg/day
- Rosuvastatin: 5–40 mg/day
- Simvastatin: 5–80 mg/day
- Pravastatin, Fluvastatin, Lovastatin, Pitavastatin
3. Fibrates
Fibrates mainly reduce triglycerides by lowering VLDL levels. They may also slightly lower LDL and raise HDL.
Examples:
- Fenofibrate: 145–160 mg/day
- Gemfibrozil: 600 mg twice daily
4. Niacin (Vitamin B3)
Niacin reduces VLDL production in the liver, lowers LDL, lowers triglycerides, and significantly increases HDL.
Examples:
- Immediate-release: 1500–3000 mg/day (divided)
- Controlled-release: 1000–2000 mg at bedtime
5. Ezetimibe
Ezetimibe reduces cholesterol absorption in the intestine. It lowers LDL and triglycerides and increases HDL, often used with statins.
Dose: 10 mg once daily
Detailed Notes:
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