BARCELONA — A variant of the adiponectin gene may have a future as a novel predictor of cardiovascular risk, Dr. Stefan Aczel reported at a joint meeting of the European Society of Cardiology and the World Heart Federation.
The G alleles of the −11377 promoter polymorphism of the adiponectin gene proved strongly predictive of increased risk of cardiovascular events independent of all standard risk factors in a prospective study involving 402 men with coronary artery disease (CAD) followed for 4 years, according to Dr. Aczel of the Academic Teaching Hospital at Feldkirch (Austria).
Serum adiponectin has been inversely associated with cardiovascular risk in some studies, but not in others. The inconsistency probably results from the fact that adiponectin levels can fluctuate widely depending upon the presence of illness, obesity, and other factors. Dr. Aczel and his coworkers decided to study promotor polymorphisms of the adiponectin gene as a potential risk predictor because the genotype—unlike serum adiponectin—remains constant, he explained in an interview.
The adiponectin gene has three different promotor variants identifiable by polymerase chain reaction (PCR): CC, GC, and GG. In the prospective study involving 402 consecutive men with CAD referred for angiography, the prevalence of the −11377 CC variant was 56.5%. The GC variant was present in 37.1%, and the GG variant occurred in 6.5%. Coronary stenosis of at least a 50% was present at baseline in 64% of men with the CC variant, in 73% with the GC, and in 89% with GG.
In all, 24% of subjects experienced one or more vascular events during follow-up. After adjustment for diabetes, lipids, age, smoking status, and other standard cardiovascular risk factors, the presence of a G-containing allele was an independent risk factor for future vascular events. Men with the GC genotype were 1.6-fold more likely to experience an event than were those with the CC genotype. Men who were GG were at an adjusted 2.4-fold increased risk.
Dr. Aczel and coworkers are interested in developing a commercial test for the G alleles. First, however, they want to confirm the associated risk in other populations, including women. They are also studying whether other gene variants associated with adiponectin—at least 13 are known—confer increased risk and might further boost risk prediction.