Clinical meaning
Comprehensive lipid panel analysis requires understanding each component's physiological significance, clinical implications, and therapeutic targets.
LDL-Cholesterol: The primary atherogenic lipoprotein. LDL-C is typically calculated using the Friedewald equation: LDL-C = Total Cholesterol - HDL-C - (Triglycerides/5). This calculation becomes INACCURATE when triglycerides exceed 400 mg/dL; in such cases, direct LDL measurement is needed. Small dense LDL particles (pattern B) are more atherogenic than large buoyant LDL (pattern A).
HDL-Cholesterol: Performs reverse cholesterol transport -- removes excess cholesterol from peripheral tissues. Low HDL is an independent cardiovascular risk factor. However, pharmacologically raising HDL has NOT been shown to reduce cardiovascular events (CETP inhibitor trials failed).
Triglycerides: Transported in VLDL particles. Mildly elevated (150-499) are associated with increased ASCVD risk. Severely elevated (>=500 mg/dL) carry significant risk of acute pancreatitis from chylomicronemia.
Non-HDL Cholesterol (Total Cholesterol - HDL-C): Captures ALL atherogenic lipoproteins (LDL + VLDL + IDL + Lp(a)). More accurate than LDL-C when triglycerides are elevated and does NOT require fasting. Non-HDL goal is typically LDL goal + 30 mg/dL.