Which feature best distinguishes statins from fibrates in their mechanism of action and lipid-lowering profile?

## Mechanism and Lipid Profile Distinction **Key Point:** Statins and fibrates differ fundamentally in their primary targets and the lipid fractions they most effectively reduce. ### Statins 1. Inhibit HMG-CoA reductase (rate-limiting enzyme in cholesterol synthesis) 2. Reduce LDL-C by 30–55% (primary effect) 3. Modest HDL-C increase (5–15%) 4. Modest triglyceride reduction (10–20%) ### Fibrates 1. Activate peroxisome proliferator-activated receptor-α (PPAR-α) 2. Reduce triglycerides by 30–50% (primary effect) 3. Increase HDL-C by 10–20% 4. Modest LDL-C reduction (10–15%) | Feature | Statins | Fibrates | |---------|---------|----------| | **Primary target** | HMG-CoA reductase | PPAR-α | | **Main effect** | ↓ LDL-C (30–55%) | ↓ TG (30–50%) | | **HDL-C change** | ↑ 5–15% | ↑ 10–20% | | **TG change** | ↓ 10–20% | ↓ 30–50% | | **CVD benefit** | Proven (LDL reduction) | Modest (TG reduction) | **High-Yield:** The discriminating feature is the PRIMARY lipid-lowering effect: statins excel at LDL reduction; fibrates excel at triglyceride reduction. This difference drives their clinical use in different dyslipidemia phenotypes. **Clinical Pearl:** A patient with elevated LDL-C and low triglycerides → statin. A patient with elevated triglycerides and low HDL-C (metabolic syndrome pattern) → fibrate.