Background: Genetic studies have identified 2 single-nucleotide polymorphisms (SNPs) at the LPA locus (rs3798220 and rs10455872) that are strongly and independently related to lipoprotein(a) levels and to coronary disease risk, but their relevance for other atherothrombotic disease is uncertain.
Methods and results: These 2 LPA SNPs were examined together as an LPA genotype score for associations with vascular outcomes among participants in the Heart Protection Study. The LPA score was examined first in 12 236 participants with prevalent vascular disease (9277 coronary disease cases, and 1326 ischemic stroke and 2011 peripheral vascular disease cases with no history of coronary disease) and 3687 vascular disease-free controls and, subsequently, in 3251 participants who had incident major vascular events during follow-up (2106 coronary disease, 507 ischemic stroke, and 707 peripheral vascular disease events). For prevalent disease, the LPA score was strongly associated with coronary disease (odds ratio [OR] per variant allele, 1.19; 95% CI, 1.08 to 1.30) and peripheral vascular disease (OR, 1.18; 95% CI, 1.04 to 1.34) but not with ischemic stroke (OR, 1.03; 95% CI, 0.89 to 1.20). Similarly, for incident disease, the LPA score was strongly associated with coronary disease (hazard ratio [HR], 1.19; 95% CI, 1.09 to 1.30) and peripheral vascular disease (HR, 1.20; 95% CI, 1.02 to 1.40) but not with ischemic stroke (HR, 0.83; 95% CI, 0.67 to 1.03).
Conclusions: The comparable strength of associations of the LPA score with coronary disease and peripheral vascular disease but not with stroke suggest that lipoprotein(a) may have effects on atherothrombotic vascular disease that are only relevant at specific sites. Clinical Trial Registration- URL: http://isrctn.org. Unique identifier: ISRCTN48489393.