title: D-allele of ACE polymorphism is associated with increased magnitude of QT dispersion prolongation in elderly Chinese: 4-year follow-up study.
abstract: BACKGROUND
  There has not been a longitudinal investigation of the influence of angiotensin-converting enzyme (ACE) insertion/deletion and angiotensinogen (AGT) M235T gene polymorphisms on repolarization parameters, such as QT dispersion (QTd) and the peak and the end of the T-wave interval (Tpe).
  
  
  RESULTS
  Electrocardiographys were recorded from 106 elderly Chinese at baseline, and 2nd and 4th year follow-up. The corrected QT (QTc), QTd, QTc dispersion (QTcd) and Tpe were manually calculated. Average age was 72.7+/-4.1 years (range 62-81). QTd, QTcd and Tpe were significantly prolonged (all p<0.001 at the 2nd and 4th year). At the 4th year the magnitude of the QTd prolongation, but not Tpe, was significantly higher in subjects carrying the ACE D allele than non-D-allele carriers (p=0.001), as was QTcd (p=0.002). This association was still significant in the multivariate analyses (p<0.001 and p=0.001 for QTc and QTcd, respectively). No significant correlation was found between repolarization parameters and AGT genotype.
  
  
  CONCLUSIONS
  This longitudinal study shows that the ageing process is associated with prolongation of QTd, QTcd and Tpe after 4 years follow-up. The elderly Chinese subjects with the ACE D-allele had greater prolongation QTd and QTcd.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Chung-Ho Memorial Hospital, Taiwan.
authors.forename: Tsung-Hsien
authors.initials: TH
authors.lastname: Lin
authors.forename: Herng-Chia
authors.initials: HC
authors.lastname: Chiu
authors.forename: Ho-Ming
authors.initials: HM
authors.lastname: Su
authors.forename: Suh-Hang Hank
authors.initials: SH
authors.lastname: Juo
authors.forename: Ya-Ting
authors.initials: YT
authors.lastname: Lee
authors.forename: Wen-Chol
authors.initials: WC
authors.lastname: Voon
authors.forename: Wen-Ter
authors.initials: WT
authors.lastname: Lai
authors.forename: Sheng-Hsiung
authors.initials: SH
authors.lastname: Sheu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000235:genetics*; D000483:Alleles; D044466:Asian People / Q000235:genetics; D002681:China / Q000208:ethnology; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008133:Long QT Syndrome / Q000208:ethnology / Q000235:genetics*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D011110:Polymorphism, Genetic
chemical_list: D007703:Peptidyl-Dipeptidase A