Ethnicity Modifies Associations between Cardiovascular Risk Factors and Disease Severity in Parallel Dutch and Singapore Coronary Cohorts

PLoS One. 2015 Jul 6;10(7):e0132278. doi: 10.1371/journal.pone.0132278. eCollection 2015.

Abstract

Background: In 2020 the largest number of patients with coronary artery disease (CAD) will be found in Asia. Published epidemiological and clinical reports are overwhelmingly derived from western (White) cohorts and data from Asia are scant. We compared CAD severity and all-cause mortality among 4 of the world's most populous ethnicities: Whites, Chinese, Indians and Malays.

Methods: The UNIted CORoNary cohort (UNICORN) simultaneously enrolled parallel populations of consecutive patients undergoing coronary angiography or intervention for suspected CAD in the Netherlands and Singapore. Using multivariable ordinal regression, we investigated the independent association of ethnicity with CAD severity and interactions between risk factors and ethnicity on CAD severity. Also, we compared all-cause mortality among the ethnic groups using multivariable Cox regression analysis.

Results: We included 1,759 White, 685 Chinese, 201 Indian and 224 Malay patients undergoing coronary angiography. We found distinct inter-ethnic differences in cardiovascular risk factors. Furthermore, the associations of gender and diabetes with severity of CAD were significantly stronger in Chinese than Whites. Chinese (OR 1.3 [1.1-1.7], p = 0.008) and Malay (OR 1.9 [1.4-2.6], p<0.001) ethnicity were independently associated with more severe CAD as compared to White ethnicity. Strikingly, when stratified for diabetes status, we found a significant association of all three Asian ethnic groups as compared to White ethnicity with more severe CAD among diabetics, but not in non-diabetics. Crude all-cause mortality did not differ, but when adjusted for covariates mortality was higher in Malays than the other ethnic groups.

Conclusion: In this population of individuals undergoing coronary angiography, ethnicity is independently associated with the severity of CAD and modifies the strength of association between certain risk factors and CAD severity. Furthermore, mortality differs among ethnic groups. Our data provide insight in inter-ethnic differences in CAD risk factors, CAD severity and mortality.

Publication types

  • Clinical Trial
  • Comparative Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Asian People*
  • Coronary Angiography*
  • Coronary Artery Disease* / diagnostic imaging
  • Coronary Artery Disease* / ethnology
  • Coronary Artery Disease* / mortality
  • Female
  • Humans
  • Male
  • Middle Aged
  • Netherlands / epidemiology
  • Netherlands / ethnology
  • Prospective Studies
  • Severity of Illness Index
  • Singapore / epidemiology
  • Singapore / ethnology
  • White People*

Grants and funding

This work is supported by a Strategic grant from the Royal Netherlands Academy of Arts and Sciences to the Interuniversity Cardiology Institute of the Netherlands, ICIN (DPVK); National University Singapore Startup grant to DPVK and Singapore National Medical Research Council Centre Grant to AMR, MYC and DPVK. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.