Article Text

Download PDFPDF
Ethnicity, heart failure, atrial fibrillation and diabetes: collider bias
  1. Andrew Felix Burden1,
  2. Nicholas Timpson2
  1. 1 NHS South Devon and Torbay Clinical Commissioning Group, Torquay, UK
  2. 2 MRC CAiTE Centre, School of Social and Community Medicine, University of Bristol, Bristol, UK
  1. Correspondence to Dr Andrew Felix Burden, Top Orchard, Broadhembury, Honiton, Devon, EX14 3LN UK; a.burden{at}nhs.net

Statistics from Altmetric.com

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

In the accompanying paper,1 Tan et al conclude that in people with heart failure (HF) there is a strikingly lower prevalence of atrial fibrillation (AF) among Asian people in Singapore compared with European people in New Zealand (NZ). When seeking an explanation for this, they found that Asian patients with HF with diabetes had less AF than Asian patients without diabetes. This lower rate of diabetes is unexpected and could be called a paradox since previous cohort studies had shown diabetes to be associated with a higher risk of AF.2 3 Both of these findings, if correct, are of importance. Ethnic differences might point to an underlying genetic cause of AF; if diabetes does not cause AF (in Asians) then lifestyle changes to prevent diabetes4 might not prevent AF, as has been suggested.5

Despite the potential interest of the findings in this work, it is important to consider that the design of the study has an important bearing on the results and their interpretation. The prevalence of AF may be lower in Asian people in Singapore, as the authors suggest, but this may be due to untestable differences in the make-up of the peoples in the study or because of a differential survivor bias, prerecruitment. Here we consider the problem of collider bias and how the structure of this study may have influenced the results and their interpretation.

Study setting and design

The paper1 is an observational study looking at data from a previous prospective multicentre longitudinal study6 based in NZ and Singapore. In this original study, patients with HF were assessed at baseline and followed over 2 years in two countries, NZ and Singapore. People were selected from 9598 presenting with HF to hospital or attending a hospital clinic for management of HF within 6 months of decompensated HF. …

View Full Text

Footnotes

  • Contributors AFB had the idea for the article. AFB and NT performed the literature search and wrote the article. AFB is the guarantor (the contributor who accepts full responsibility for the finished article, had access to any data and controlled the decision to publish).

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Provenance and peer review Commissioned; internally peer reviewed.

  • Patient consent for publication Not required.

Linked Articles

  • Heart failure and cardiomyopathies
    Eugene S J Tan Wan Ting Tay Tiew-Hwa Katherine Teng David Sim Kui Toh Gerard Leong Poh Shuan Daniel Yeo Hean Yee Ong Fazlur Jaufeerally Tze Pin Ng Katrina Poppe Mayanna Lund Gerard Devlin Richard W Troughton Lieng Hsi Ling Arthur Mark Richards Robert N Doughty Carolyn S P Lam
  • Correspondence
    Eugene S J Tan Wan Ting Tay Tiew-Hwa Katherine Teng Arthur Mark Richards Robert N Doughty Carolyn S P Lam