TY - JOUR
T1 - Revisiting ethnic discrepancies in COVID-19 hospitalized cohorts
T2 - a correction for collider bias
AU - Learoyd, Annastazia e.
AU - Nicholas, Jennifer
AU - Hart, Nicholas
AU - Douiri, Abdel
N1 - Funding Information:
Funding: The authors acknowledge funding support from the National Institute for Health Research (NIHR) Applied Research Collaboration South London at King's College Hospital NHS Foundation Trust and the Royal College of Physicians , as well as the King's Health Partners/Guy's and St Thomas Charity ‘MLTC Challenge Fund’ (grant number EIC180702 ). We also acknowledge support from the NIHR Biomedical Research Centre based at Guy's and St Thomas' NHS Foundation Trust and King's College London.
Publisher Copyright:
© 2023 The Author(s)
PY - 2023/9
Y1 - 2023/9
N2 - Objectives: Studies from the first waves of the coronavirus disease 2019 (COVID-19) pandemic suggest that individuals from minority ethnicities are at an increased risk of worse outcomes. Concerns exist that this relationship is potentially driven by bias from analyzing hospitalized patients only. We investigate this relationship and the possible presence of bias. Study Design and Setting: Using data from South London hospitals across two COVID-19 waves (February 2020 – May 2021), the relationship between ethnicity and COVID-19 outcomes was examined using regression models. Three iterations of each model were completed: 1) an unadjusted analysis, 2) adjusting for covariates (medical history and deprivation), and 3) adjusting for covariates and bias induced by conditioning on hospitalization. Results: Among 3,133 patients, those who were Asian had a two-fold increased risk of death during the hospital stay that was consistent across the two COVID-19 waves and was not affected by correcting for conditioning on hospitalization. However, wave-specific effects demonstrate significant differences between ethnic groups until bias from using a hospitalized cohort was corrected for. Conclusion: Worsened COVID-19 outcomes in minority ethnicities may be minimized by correcting for bias induced by conditioning on hospitalization. Consideration of this bias should be a key component of study design.
AB - Objectives: Studies from the first waves of the coronavirus disease 2019 (COVID-19) pandemic suggest that individuals from minority ethnicities are at an increased risk of worse outcomes. Concerns exist that this relationship is potentially driven by bias from analyzing hospitalized patients only. We investigate this relationship and the possible presence of bias. Study Design and Setting: Using data from South London hospitals across two COVID-19 waves (February 2020 – May 2021), the relationship between ethnicity and COVID-19 outcomes was examined using regression models. Three iterations of each model were completed: 1) an unadjusted analysis, 2) adjusting for covariates (medical history and deprivation), and 3) adjusting for covariates and bias induced by conditioning on hospitalization. Results: Among 3,133 patients, those who were Asian had a two-fold increased risk of death during the hospital stay that was consistent across the two COVID-19 waves and was not affected by correcting for conditioning on hospitalization. However, wave-specific effects demonstrate significant differences between ethnic groups until bias from using a hospitalized cohort was corrected for. Conclusion: Worsened COVID-19 outcomes in minority ethnicities may be minimized by correcting for bias induced by conditioning on hospitalization. Consideration of this bias should be a key component of study design.
UR - http://www.scopus.com/inward/record.url?scp=85168369660&partnerID=8YFLogxK
U2 - 10.1016/j.jclinepi.2023.06.014
DO - 10.1016/j.jclinepi.2023.06.014
M3 - Article
SN - 0895-4356
VL - 161
SP - 94
EP - 103
JO - Journal of Clinical Epidemiology
JF - Journal of Clinical Epidemiology
ER -