Chromosome 9p21 haplotypes and prognosis in white and black patients with coronary artery disease.

BACKGROUND

Although numerous single-nucleotide polymorphisms (SNPs) in chromosome 9p21 have been associated with coronary artery disease (CAD) and incident myocardial infarction (MI) in whites, there are limited and conflicting reports on the association of this locus with prognosis in whites with existing CAD and no reports in blacks or Hispanics. We investigated the hypothesis that 9p21 polymorphisms are associated with increased risk for adverse cardiovascular outcomes in patients with documented CAD.

METHODS AND RESULTS

We studied the association of 155 chromosome 9p21 SNPs with adverse outcomes among hypertension patients with CAD of multiple races/ethnicities in INVEST-GENES (the International Verapamil SR Trandolapril Study Genetic Substudy) (n=1460 and n=5979 for 2 SNPs) with replication testing of 4 SNPs in the INFORM (Investigation of Outcomes From Acute Coronary Syndrome) study (n=714) of patients with acute coronary syndromes. In INVEST, the haplotype comprising the risk allele for the widely reported 9p21 SNPs was associated with better prognosis in whites (odds ratio [OR], 0.72; 95% CI, 0.57 to 0.92; P=0.0085) but not in blacks (OR, 1.21; 95% CI, 0.68 to 1.24; P=0.52) or Hispanics (OR, 0.96; 95% CI, 0.65 to 1.44; P=0.86). A less commonly reported linkage disequilibrium block was associated with worse prognosis in INVEST in both whites (OR, 1.52; 95% CI, 1.20 to 1.93; P=0.0006) and blacks (OR, 4.11; 95% CI, 1.55 to 10.88; P=0.004).

CONCLUSIONS

Our findings suggest that previously reported chromosome 9p21 SNPs, which predict incident CAD, are not associated with higher risk for adverse outcomes in patients with established CAD. The less commonly reported linkage disequilibrium block warrants further investigation. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00133692.