title: The ethnicity-specific association of biomarkers with the angiographic severity of coronary artery disease.
abstract: BACKGROUND
  Risk factor burden and clinical characteristics of patients with coronary artery disease (CAD) differ among ethnic groups. We related biomarkers to CAD severity in Caucasians, Chinese, Indians and Malays.
  
  
  METHODS
  In the Dutch-Singaporean UNICORN coronary angiography cohort (n = 2033) we compared levels of five cardiovascular biomarkers: N-terminal pro-brain natriuretic peptide (NTproBNP), high-sensitivity C-reactive protein (hsCRP), cystatin C (CysC), myeloperoxidase (MPO) and high-sensitivity troponin I (hsTnI). We assessed ethnicity-specific associations of biomarkers with CAD severity, quantified by the SYNTAX score.
  
  
  RESULTS
  Adjusted for baseline differences, NTproBNP levels were significantly higher in Malays than in Chinese and Caucasians (72.1 vs. 34.4 and 41.1 pmol/l, p < 0.001 and p = 0.005, respectively). MPO levels were higher in Caucasians than in Indians (32.8 vs. 27.2 ng/ml, p = 0.026), hsTnI levels were higher in Malays than in Caucasians and Indians (33.3 vs. 16.4 and 17.8 ng/l, p < 0.001 and p = 0.029) and hsTnI levels were higher in Chinese than in Caucasians (23.3 vs. 16.4, p = 0.031). We found modifying effects of ethnicity on the association of biomarkers with SYNTAX score. NTproBNP associated more strongly with the SYNTAX score in Malays than Caucasians (β 0.132 vs. β 0.020 per 100 pmol/l increase in NTproBNP, p = 0.032). For MPO levels the association was stronger in Malays than Caucasians (β 1.146 vs. β 0.016 per 10 ng/ml increase, p = 0.017). Differing biomarker cut-off levels were found for the ethnic groups.
  
  
  CONCLUSIONS
  When corrected for possible confounders we observe ethnicity-specific differences in biomarker levels. Moreover, biomarkers associated differently with CAD severity, suggesting that ethnicity-specific cut-off values should be considered.
authors.affiliation: Laboratory of Experimental Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.|The Netherlands Heart Institute (ICIN), Utrecht, The Netherlands.
authors.forename: C M
authors.initials: CM
authors.lastname: Gijsberts
authors.affiliation: Cardiac Department, National University Heart Centre, National University Hospital, Singapore, Singapore.
authors.forename: A
authors.initials: A
authors.lastname: Seneviratna
authors.affiliation: Laboratory of Experimental Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.|The Netherlands Heart Institute (ICIN), Utrecht, The Netherlands.
authors.forename: I E M
authors.initials: IE
authors.lastname: Bank
authors.affiliation: Laboratory of Experimental Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: H M
authors.initials: HM
authors.lastname: den Ruijter
authors.affiliation: Laboratory of Experimental Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.|Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.|Durrer Center for Cardiogenetic Research, ICIN-Netherlands Heart Institute, Utrecht, The Netherlands.|Institute of Cardiovascular Science, faculty of Population Health Sciences, University College London, London, United Kingdom.
authors.forename: F W
authors.initials: FW
authors.lastname: Asselbergs
authors.affiliation: Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: Agostoni
authors.affiliation: Clinical Chemistry and Hematology, Gelre Hospitals, Apeldoorn, The Netherlands.
authors.forename: J A
authors.initials: JA
authors.lastname: Remijn
authors.affiliation: Laboratory of Experimental Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.|The Netherlands Heart Institute (ICIN), Utrecht, The Netherlands.
authors.forename: G
authors.initials: G
authors.lastname: Pasterkamp
authors.affiliation: Department of Paediatrics, National University of Singapore, Singapore, Singapore.
authors.forename: H C
authors.initials: HC
authors.lastname: Kiat
authors.affiliation: Clinical Chemistry and Hematology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Roest
authors.affiliation: Cardiac Department, National University Heart Centre, National University Hospital, Singapore, Singapore.|Cardiovascular Research Institute, National University Heart Centre, National University Health System, Singapore, Singapore.
authors.forename: A M
authors.initials: AM
authors.lastname: Richards
authors.affiliation: Cardiac Department, National University Heart Centre, National University Hospital, Singapore, Singapore.|Cardiovascular Research Institute, National University Heart Centre, National University Health System, Singapore, Singapore.
authors.forename: M Y
authors.initials: MY
authors.lastname: Chan
authors.affiliation: The Netherlands Heart Institute (ICIN), Utrecht, The Netherlands. surdvp@nus.edu.sg.|Cardiovascular Research Institute, National University Heart Centre, National University Health System, Singapore, Singapore. surdvp@nus.edu.sg.
authors.forename: D P V
authors.initials: DP
authors.lastname: de Kleijn
authors.affiliation: Laboratory of Experimental Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.|Clinical Chemistry and Hematology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: I E
authors.initials: IE
authors.lastname: Hoefer
keywords: Biomarkers; Coronary angiography; Ethnicity; Singapore