title: Analysis of circulating cholesterol levels as a mediator of an association between ABO blood group and coronary heart disease.
abstract: BACKGROUND
  Non-O type of ABO blood group has been associated with a predisposition to coronary heart disease. It is thought that this association is partly mediated by increased cholesterol levels in non-O-type individuals. In this study, we sought to estimate the mediation effect size.
  
  
  RESULTS
  In a group of individuals (n=6476) undergoing coronary angiography, we detected associations of non-O type with significant coronary artery disease with >50% stenosis in ≥1 coronary arteries (odds ratio, 1.24; 95% confidence interval, 1.10-1.39; P=2.6×10(-4)) and with prevalent or incident myocardial infarction (odds ratio, 1.22; 95% confidence interval, 1.09-1.37; P=1.2×10(-3)). Subjects of non-O type had higher levels of total cholesterol, low-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol (mean [SEM] in mmol/L: 4.931[0.021], 3.041 [0.018], and 3.805 [0.020] in non-O type compared with 4.778 [0.026], 2.906 [0.021], and 3.669 [0.024] in O type; P=3.8×10(-7), P=1.5×10(-7), and P=3.1×10(-7), respectively). Mediation analyses indicated that 10% of the effect of non-O type on coronary artery disease susceptibility was mediated by increased low-density lipoprotein cholesterol level (P=7.8×10(-4)) and that 11% of the effect of non-O type on myocardial infarction risk was mediated by raised low-density lipoprotein cholesterol level (P=2.0×10(-3)).
  
  
  CONCLUSIONS
  In a model in which it is presumed that cholesterol is a mediator of the associations of ABO group with coronary artery disease and myocardial infarction, around 10% of the effect of non-O type on coronary artery disease and myocardial infarction susceptibility was mediated by its influence on low-density lipoprotein cholesterol level.
authors.affiliation: Department of Cardiology, First Affiliated Hospital of Shantou University Medical College, Shantou, China.
authors.forename: Yequn
authors.initials: Y
authors.lastname: Chen
authors.forename: Chang
authors.initials: C
authors.lastname: Chen
authors.forename: Xiayi
authors.initials: X
authors.lastname: Ke
authors.forename: Longgen
authors.initials: L
authors.lastname: Xiong
authors.forename: Yongying
authors.initials: Y
authors.lastname: Shi
authors.forename: Jiafu
authors.initials: J
authors.lastname: Li
authors.forename: Xuerui
authors.initials: X
authors.lastname: Tan
authors.forename: Shu
authors.initials: S
authors.lastname: Ye
mesh_terms: D000017:ABO Blood-Group System / Q000097:blood*; D000368:Aged; D002784:Cholesterol / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood; D017023:Coronary Angiography; D003327:Coronary Disease / Q000097:blood* / Q000453:epidemiology / Q000473:pathology; D023921:Coronary Stenosis / Q000209:etiology; D004198:Disease Susceptibility; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000453:epidemiology / Q000209:etiology; D016017:Odds Ratio; D015995:Prevalence; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood
chemical_list: D000017:ABO Blood-Group System; D008078:Cholesterol, LDL; D014280:Triglycerides; D002784:Cholesterol
keywords: ABO blood-group system; cholesterol; cholesterol, LDL; coronary disease; myocardial infarction