A common variant of the AMPD1 gene predicts improved cardiovascular survival in patients with coronary artery disease

Abstract

OBJECTIVEWe tested whether a common AMPD1 gene variant is associated with improved cardiovascular (CV) survival in patients with coronary artery disease (CAD).BACKGROUNDReduced activity of adenosine monophosphate deaminase (AMPD) may increase production of adenosine, a cardioprotective agent. A common, nonsense, point variant of the AMPD1 gene (C34T) results in enzymatic inactivity and has been associated with prolonged survival in heart failure.METHODSBlood was collected from 367 patients undergoing coronary angiography. Genotyping was done by polymerase chain reaction amplification and restriction enzyme digestion, resulting in allele-specific fragments. Coronary artery disease was defined as ≥70% stenosis of ≥1 coronary artery. Patients were followed prospectively for up to 4.8 years. Survival statistics compared hetero- (+/−) or homozygotic (−/−) carriers with noncarriers.RESULTSPatients were 66 ± 10 years old; 79% were men; 22.6% were heterozygous and 1.9% homozygous for the variant AMPD1(−) allele. During a mean of 3.5 ± 1.0 years, 52 patients (14.2%) died, 37 (10.1%) of CV causes. Cardiovascular mortality was 4.4% (4/90) in AMPD1(−) allele carriers compared with 11.9% (33/277) in noncarriers (p = 0.046). In multiple variable regression analysis, only age (hazard ratio, 1.11/year, p < 0.001) and AMPD1(−) carriage (hazard ratio, 0.36, p = 0.053) were independent predictors of CV mortality.CONCLUSIONSCarriage of a common variant of the AMPD1 gene was associated with improved CV survival in patients with angiographically documented CAD. The dysfunctional AMPD1(−) allele may lead to increased cardiac adenosine and increased cardioprotection during ischemic events. Adenosine monophosphate deaminase-1 genotyping should be further explored in CAD for prognostic, mechanistic and therapeutic insights.