In one study, 25,131 initially healthy Caucasian participants in the Women's Health Study were followed for ~10 years. rs3798220(C) allele carriers (3.7%) in the placebo (i.e. not receiving aspirin) group had a 2x higher risk of major cardiovascular events than non-carriers (age-adjusted hazard ratio (HR) of 2.21, CI: 1.39-3.52). Among rs3798220(C) carriers, the risk was reduced more than twofold by aspirin: for aspirin compared with placebo the age-adjusted HR was 0.44 (CI: 0.20-0.94). The risk was not significantly reduced among non-carriers (age-adjusted HR=0.91, CI: 0.77-1.08). This interaction between carrier status and aspirin allocation was significant (P=0.048). In summary, rs3798220(C) carriers had higher plasma lipoprotein(a) and had double the risk of cardiovascular events, but also benefited more from taking aspirin.[PMID:18775538]

In another study, compared with noncarriers, carriers of the 4399M risk allele (2.7% of controls) had an adjusted odds ratio for severe CAD of 3.14 (CI: 1.51 to 6.56), and had 5-fold higher median plasma lipoprotein(a) levels (P=0.003), leading to the conclusion that the LPA I4399M SNP is associated with severe CAD and plasma lipoprotein(a) levels.[PMID:17569884]