Relationship of LDL-C and Lp(a) to Cardiovascular Risk in MESA

This MESA sub-study enrolled 4,585 statin-naïve adults to determine whether elevated Lp(a) (≥50 mg/dL) conferred increased coronary heart disease risk even when LDL-C was at goal (≤100 mg/dL), and whether LDL-C and Lp(a) interacted in their associations with CHD.

Elevated Lp(a) was associated with significantly higher CHD risk regardless of LDL-C level. Among participants with LDL-C ≤100 mg/dL, elevated Lp(a) was associated with a hazard ratio of 1.83 for CHD — a robust and clinically meaningful elevated risk despite “controlled” LDL. Conversely, elevated LDL-C without elevated Lp(a) was not independently associated with CHD in this analysis. Elevated Lp(a) was the stronger independent predictor.

The clinical implication is direct: a patient with LDL-C of 95 mg/dL and Lp(a) of 75 mg/dL is at substantially higher risk than a patient with LDL-C of 95 mg/dL and Lp(a) of 15 mg/dL. Standard lipid panels, which do not measure Lp(a), miss this distinction entirely. The MESA data support routine Lp(a) measurement in cardiovascular risk assessment — particularly in patients who appear at low-to-intermediate risk by LDL-C criteria.

The statin-naïve design isolates the epidemiological association without confounding by treatment differences, strengthening the causal interpretation.

We rate the evidence moderate. A well-analyzed MESA cohort study establishing Lp(a) as a dominant independent CHD predictor even at controlled LDL-C levels — supporting universal Lp(a) measurement in risk assessment.