Nonfasting lipid analysis is acceptable for two analytes. Which is NOT among them?

• A. LDL-C
• B. Total Cholesterol
• C. HDL-C
• D. Triglycerides

Answer: (A)

Fasting status matters for lipid measurements because the LDL-C value is usually calculated using the Friedewald equation, which relies on a stable, fasting level of triglycerides. After a meal, triglycerides rise (postprandial lipemia), which makes that calculation unreliable. Because of this, LDL-C isn’t considered reliably reportable from a nonfasting sample. In contrast, total cholesterol and HDL-C are relatively stable despite meals and can be reported from nonfasting samples. Triglycerides can be measured nonfasting but their values are more variable and interpretation is limited. Therefore, LDL-C is the analyte that is not among the two typically acceptable nonfasting measurements.