Lipoprotein(a) Levels, Genotype, and Incident Aortic Valve Stenosis

Lipoprotein(a) is best known as a risk factor for heart attacks. This study helped establish that its reach extends to the aortic valve — the stiffening, calcifying disease that eventually requires valve replacement.

Using the EPIC-Norfolk cohort with replication in a Montreal biobank, the authors showed that high Lp(a) levels predicted incident aortic stenosis, with levels above 50 mg/dL roughly doubling the risk. More tellingly, they used the genetic approach: a common variant that raises Lp(a) from birth was itself associated with valve disease, in a striking dose pattern — carrying two copies raised risk nearly fivefold. Because genes are fixed at conception and cannot be confounded by lifestyle, this genetic signal is powerful evidence that Lp(a) does not merely accompany valve disease but causes it.

That causal inference is what gives the study weight. It reframed calcific aortic stenosis — long considered simple wear-and-tear — as a partly lipid-driven disease, and opened the door to the idea that lowering Lp(a) might one day prevent it.

We rate the evidence strong. The Mendelian randomization design, plus replication, lifts it well above a simple association study, even though no therapy yet exists to act on the finding.