Risk of Thrombosis Following the First Dose of ChAdOx1 nCoV-19 Vaccine in Patients Undergoing Maintenance Hemodialysis: A Self-Controlled Case Series Study

Shih-Chieh Shao; Tzu-Chi Liao; Kai-Cheng Chang; Hui-Yu Chen; Swu-Jane Lin; Cheng-Yang Hsieh; Edward Chia-Cheng Lai

doi:10.2147/IJGM.S418741

Risk of Thrombosis Following the First Dose of ChAdOx1 nCoV-19 Vaccine in Patients Undergoing Maintenance Hemodialysis: A Self-Controlled Case Series Study

Int J Gen Med. 2023 Sep 5:16:4017-4025. doi: 10.2147/IJGM.S418741. eCollection 2023.

Authors

Shih-Chieh Shao^{1

2}, Tzu-Chi Liao¹, Kai-Cheng Chang^{1

3}, Hui-Yu Chen³, Swu-Jane Lin⁴, Cheng-Yang Hsieh^{1

5}, Edward Chia-Cheng Lai¹

Affiliations

¹ School of Pharmacy, Institute of Clinical Pharmacy and Pharmaceutical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
² Department of Pharmacy, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan.
³ Department of Pharmacy, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan.
⁴ Department of Pharmacy Systems, Outcomes and Policy, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA.
⁵ Department of Neurology, Tainan Sin Lau Hospital, Tainan, Taiwan.

Abstract

Background: The ChAdOx1 nCoV-19 vaccine is associated with vaccine-induced thrombosis and thrombocytopenia (VITT). Patients with end-stage renal disease (ESRD) under hemodialysis are at elevated risk of heparin-induced thrombocytopenia, which shares similar mechanisms with VITT. We aimed to examine the risk of VITT after the first dose of ChAdOx1 nCoV-19 vaccine using a self-controlled case series analysis (SCCS) in the hemodialyzed ESRD population.

Methods: Drawing from the largest multi-center electronic medical records database in Taiwan, we identified adult patients, with or without hemodialysis, between 1st December, 2020, and 31st December, 2021, who received a first dose of ChAdOx1 nCoV-19 vaccine and had an outcome of thrombocytopenia, venous thrombosis, or arterial thrombosis. We calculated the incident rate ratios (IRRs) of outcomes in different periods at risk, compared to periods not at risk.

Results: We identified 59 hemodialysis patients and 41 non-dialysis patients with an outcome. The SCCS analyses showed, for the hemodialysis group, a significantly increased risk of outcomes during the period 31 to 60 days post-exposure to ChAdOx1 nCoV-19 vaccine (IRR: 2.823; 95% CI: 1.423-5.600). However, in non-dialysis patients there was no increase in risks during any of the post-exposure risk periods.

Conclusion: For ESRD patients under hemodialysis, the first dose of ChAdOx1 nCoV-19 vaccine was associated with a 2.8-fold increase in risk of thrombosis.

Keywords: ChAdOx1 nCoV-19 vaccine; end-stage renal disease; hemodialysis; thrombocytopenia; thrombosis.

Grants and funding

This research was funded by Tainan Sin Lau Hospital, under grant number SLH-111-07. The funder had no part in this study, including study design and conduct, data collection, management, analysis and interpretation, manuscript preparation, review and approval, and decision to publish.