The common apolipoprotein A-1 polymorphism -75A>G is associated with ethnic differences in recurrent coronary events after recovery from an acute myocardial infarction
Abstract:
Overview
Since data regarding the relationship between a common polymorphism (SNP) of the apoA1 gene with apoA1 levels and risk of coronary artery disease are inconsistent, we hypothesized that its association with recurrent coronary events differs for White and Black individuals with diagnosed coronary heart disease. The apoA1 -75G>A SNP was genotyped in a cohort of 834 Black (n=129) and White (n=705) post-myocardial infarction patients. Recurrent coronary events (coronary-related death, non-fatal myocardial infarction, or unstable angina) were documented during an average follow-up of 28 months. Thirty percent of White and 21% of Black patients carried the SNP. Cox proportional-hazards regression analysis, adjusting for clinical and laboratory covariates, demonstrated that the SNP was not associated with recurrent events in the total cohort (HR=1.37, 95% CI 0.95-1.97; p=0.09) but was the only variable associated with an increased risk of recurrent cardiac events in Blacks (HR=2.40, 95% CI 1.07-5.40; p= 0.034). Conversely in Whites, the SNP was not associated with recurrent events (HR=1.12, 95% CI 0.75-1.67; p= 0.59) whereas apoB (HR=1.78, 95% CI 1.20 -2.65; p=0.0042) and calcium channel blocker use (HR=2.53, 95% CI 1.72-3.72; p<0.001) were associated; p=0.0024 for interaction between ethnicity and the SNP. A common apoA1 SNP is associated with a significantly increased risk of recurrent cardiac events among Black, but not White, postmyocardial infarction patients. Relationships with lipoproteins may help explain this finding.
Keywords
Apolipoprotein A1, high density lipoprotein, African-American, recurrent coronary event, myocardial infarction.
Article:
Article Information:
Correspondence
Robert C. Block, MD, MPH Box 644, 601 Elmwood Avenue Rochester, NY 14642 Email: robert_block@urmc.rochester.edu
Acknowledgements
We thank Paul Winters for his
assistance with the creation of the figure.
This study was supported by Research Grant
HL048259 from the National Institutes of Health,
Bethesda, Maryland, and by a contract from
Millennium Pharmaceuticals, Inc., Cambridge,
Massachusetts, USA.
This research was carried out at the University
of Rochester.
This publication was made possible by Grant
Number KL2 RR 024136 from the National Center
for Research Resources (NCRR), a component of
the National Institutes of Health (NIH), and the
NIH Roadmap for Medical Research. Its contents
are solely the responsibility of the authors and do
not necessarily represent the official view of
NCRR or NIH. Information on NCRR is available
at http://www.ncrr.nih.gov/. Information on Reengineering
the Clinical Research Enterprise can
be obtained from http://nihroadmap.nih.gov/clinicalresearch/
overview-translational.asp
Received
2009-06-26T00:00:00