Clinical application of chromosome 9p21.3 genotyping in patients with coronary artery disease

The aim of the present study was to investigate the susceptibility of two coronary artery disease (CAD)-associated single nucleotide polymorphisms on 9p21 (rs1333049 and rs10757278) to myocardial infarction (MI) in a primary (stratification of high risk group for MI) and secondary prevention setting. The prospective observational study included 500 patients with MI [411 males (82.2%) and 89 females (17.8%)] under 65 years. The risk of MI for carriers of the homozygous CC genotype of rs1333049 and homozygous GG genotype of rs10757278 was 1.77 [95% confidence interval (CI): 1.36-2.37], and 1.70 (95% CI: 1.24-2.32) respectively. The risk of MI for heterozygous allele carriers was slightly lower. Specifically, the risk of MI was 1.58 (95% CI: 1.18-2.11) for both heterozygous and homozygous carriers of the rs1333049 C allele, and 1.36 (95% CI: 1.01-1.83) for the carriers of the rs10757278 G allele. A logistic regression model including sex, age, presence of excess weight or obesity, abdominal obesity, diabetes mellitus, arterial hypertension, hypercholesterolemia, positive family history and smoking status parameters revealed that rs1333049 CC genotype was an independent predictive factor of myocardial infraction [OR=1.71 (95% CI: 1.16-2.52), P=0.006]. Patients who underwent percutaneous coronary intervention (PCI) during index hospitalization and patients who did not receive PCI were followed up for two years after discharge. Compared with patients with MI who underwent PCI, the risk of recurrent acute coronary syndrome (re-ACS) was higher among rs1333049 C allele carriers who did not receive PCI during index hospitalization. One year after MI, the OR of re-ACS was 4.91 (95% CI: 1.45-16.66), while two years after MI, OR was 3.77 (95% CI: 1.50-9.52) in those patients who did not receive PCI during index hospitalization. There was no statistically significant association between polymorphic variants of rs1333049 and MI follow-up outcomes in patients who underwent PCI. The present study indicated clinical utility of 9p21.3 genotyping to predict the outcomes for patients with MI without PCI. Due to the small sample size, this association study forms basis for larger, nationwide studies investigating clinical applications of genetic data.