title: Angiotensin-converting enzyme I/D polymorphism and aortic aneurysm risk: a meta-analysis.
abstract: OBJECTIVE
  Angiotensin-converting enzyme (ACE) I/D polymorphism has been implicated in aortic aneurysm risk, but individual published studies show inconclusive results. The aim of this study was to explore a more precise estimation of its relation with aortic aneurysm using meta-analysis.
  
  
  METHODS
  Electronic searches of PubMed and EMBASE databases were conducted for all publications through February 2014. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to access the strength of this association in the random-effects model or fixed-effects model.
  
  
  RESULTS
  Fourteen case-control studies, including a total of 3938 cases and 5748 controls, were included. This meta-analysis showed a significant association between ACE I/D polymorphism and aortic aneurysm risk (OR = 1.53, 95% CI 1.26-1.87, P <0.01). In the subgroup analysis by ethnicity, a statistically significant association was found in Caucasians (OR = 1.46, 95% CI 1.20-1.77, P <0.01), but not in Asians. In the subgroup analysis by type of aortic aneurysm, this polymorphism was significantly associated with abdominal aortic aneurysm risk (OR = 1.38, 95% CI 1.10-1.74, P <0.01), thoracic aortic aneurysm risk (OR = 1.59, 95% CI 1.11-2.29, P = 0.01) and aortic dissection risk (OR = 2.43, 95% CI 1.07-5.52, P = 0.03). Stratification by hypertension status showed that hypertensive patients with this polymorphism were associated with increased aortic aneurysm risk (OR = 1.47, 95% CI 1.03-2.09, P = 0.03), whereas normotensive individuals with this polymorphism did not have an increased aortic aneurysm risk.
  
  
  CONCLUSIONS
  This meta-analysis suggested that ACE I/D polymorphism was associated with aortic aneurysm risk.
authors: Department of Vascular Surgery, Chengde Central Hospital, Chengde, Hebei Province, China.
authors: Le-Gang
authors: LG
authors: Huang
authors: Department of Vascular Surgery, Chengde Central Hospital, Chengde, Hebei Province, China.
authors: Dong-Bo
authors: DB
authors: Liu
authors: Department of Vascular Surgery, Jining No. 1 People's Hospital, Jining, Shandong Province, China 38477015@qq.com.
authors: Hai-Qing
authors: HQ
authors: Wang
mesh_terms: D001014:Aortic Aneurysm / Q000201:enzymology / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006801:Humans; D007703:Peptidyl-Dipeptidase A / Q000235:genetics* / Q000378:metabolism; D011110:Polymorphism, Genetic; D012307:Risk Factors
chemical_list: C488034:ACE protein, human; D007703:Peptidyl-Dipeptidase A
keywords: Angiotensin-converting enzyme; Aortic aneurysm; Meta-analysis; Polymorphism