CLS Lipid Panel Interpretation 3 — Questions and Answers
Question 1: A 52-year-old woman has LDL-C 135 mg/dL, HDL-C 42 mg/dL, TG 155 mg/dL, and TC 208 mg/dL. Her 10-year ASCVD risk is 9.8%. According to ACC/AHA guidelines, what is the most appropriate next step?
- Initiate high-intensity statin therapy immediately
- Discuss risk-enhancing factors and consider moderate-intensity statin (Correct answer)
- Reassure and recheck in 5 years without treatment
- Order Lp(a) and defer any decision until results return
Correct answer: Discuss risk-enhancing factors and consider moderate-intensity statin
For intermediate-risk patients (7.5–20% 10-year ASCVD risk), ACC/AHA guidelines recommend a risk discussion incorporating risk-enhancing factors before initiating moderate-intensity statin therapy.
Question 2: Which of the following best defines the LDL-C treatment goal for a patient with established ASCVD and a recent ACS event (very high-risk)?
- <100 mg/dL
- <70 mg/dL
- <55 mg/dL (Correct answer)
- <40 mg/dL
Correct answer: <55 mg/dL
For very high-risk ASCVD patients (including those with recent ACS), 2022 ACC/AHA guidelines recommend an LDL-C goal of <55 mg/dL with a ≥50% reduction from baseline.
Question 3: A fasting lipid panel shows TC 240 mg/dL, HDL-C 60 mg/dL, TG 100 mg/dL, LDL-C 160 mg/dL. Calculated non-HDL is 180 mg/dL. How does this panel affect ASCVD risk interpretation?
- TC alone is sufficient to classify high risk without further analysis
- High HDL-C partially offsets the elevated LDL-C and should be factored into risk assessment (Correct answer)
- Non-HDL >160 mg/dL alone mandates statin initiation regardless of other factors
- Triglycerides at 100 mg/dL indicate normal metabolism and require no further evaluation
Correct answer: High HDL-C partially offsets the elevated LDL-C and should be factored into risk assessment
HDL-C ≥60 mg/dL is considered a negative risk factor that partially offsets cardiovascular risk and should be incorporated into overall ASCVD risk assessment alongside other lipid values.
Question 4: A patient on maximally tolerated statin plus ezetimibe has LDL-C 78 mg/dL with very high-risk ASCVD. Which interpretation is most accurate?
- Goal is achieved; no further therapy is needed
- LDL-C remains above the <55 mg/dL very-high-risk target; PCSK9 inhibitor addition is appropriate (Correct answer)
- Ezetimibe should be discontinued and replaced with a fibrate
- Non-HDL-C should now become the sole treatment target
Correct answer: LDL-C remains above the <55 mg/dL very-high-risk target; PCSK9 inhibitor addition is appropriate
For very high-risk ASCVD patients with LDL-C above 55 mg/dL despite maximally tolerated statin plus ezetimibe, adding a PCSK9 inhibitor is guideline-supported to achieve the LDL-C goal.
Question 5: Which lipid panel component most directly reflects the number of atherogenic lipoprotein particles when LDL-C and triglycerides are discordant?
- Total cholesterol
- HDL-C
- Apolipoprotein B (Correct answer)
- VLDL-C
Correct answer: Apolipoprotein B
Apolipoprotein B (apoB) measures the total number of atherogenic lipoprotein particles (each containing one apoB molecule) and provides more accurate risk assessment than LDL-C when there is LDL-TG discordance.
Question 6: A patient's lipid panel reveals TG 900 mg/dL. The plasma appears milky (lactescent). What is the most immediate concern?
- Increased ASCVD risk requiring urgent statin initiation
- Risk of acute pancreatitis requiring triglyceride-lowering therapy (Correct answer)
- Underestimated LDL-C requiring direct LDL measurement
- Spuriously elevated HDL-C requiring repeat fasting sample
Correct answer: Risk of acute pancreatitis requiring triglyceride-lowering therapy
Triglycerides above 500–1000 mg/dL (lactescent plasma) carry significant risk of acute pancreatitis, which is the immediate clinical priority requiring urgent intervention with fibrates, omega-3s, and dietary fat restriction.
Question 7: Lp(a) levels are measured separately from a standard lipid panel. What is the primary clinical reason to order Lp(a)?
- To calculate a more accurate LDL-C when triglycerides are elevated
- To identify a genetically determined residual ASCVD risk factor not captured by standard lipid panel (Correct answer)
- To guide fibrate therapy selection in hypertriglyceridemia
- To assess response to statin therapy over time
Correct answer: To identify a genetically determined residual ASCVD risk factor not captured by standard lipid panel
Lp(a) is a genetically determined, largely statin-unresponsive lipoprotein that represents an independent ASCVD risk factor, and its measurement identifies residual risk missed by standard lipid panels.
CLS Lipid Panel Interpretation 3
A 52-year-old woman has LDL-C 135 mg/dL, HDL-C 42 mg/dL, TG 155 mg/dL, and TC 208 mg/dL.
Her 10-year ASCVD risk is 9.8%.
According to ACC/AHA guidelines, what is the most appropriate next step?