β 2 -Adrenergic Receptor Polymorphisms and Risk of Incident Cardiovascular Events in the Elderly

Abstract

Background— Genetic polymorphisms at codons 16 and 27 of the β 2 -adrenergic receptor have been associated with altered response to sympathetic stimulation. We examined these polymorphisms in relation to cardiovascular event risk in the Cardiovascular Health Study. Methods and Results— A total of 808 black and 4441 white participants (mean age, 73 years) were genotyped for the Arg16Gly and Gln27Glu polymorphisms of the β 2 -adrenergic receptor. There were 702 incident coronary events, 438 ischemic strokes, and 1136 combined cardiovascular events during 7 to 10 years of follow-up. Allele frequencies differed by race but not by age or hypertension status. Glu27 carriers had a lower risk of coronary events than Gln27 homozygotes (hazard ratio, 0.82; 95% CI, 0.70 to 0.95), and there was a suggestion of decreased risk among Gly16 carriers compared with Arg16 homozygotes (hazard ratio, 0.88; 95% CI, 0.72 to 1.07). There was no association of β 2 -adrenergic receptor genotype with ischemic stroke or combined cardiovascular events. Conclusions— The Glu27 allele of the β 2 -adrenergic receptor was associated with a lower risk of incident coronary events in this elderly population.