Second-dose ChAdOx1 and BNT162b2 COVID-19 vaccines and thrombocytopenic, thromboembolic and hemorrhagic events in Scotland

We investigated thrombocytopenic, thromboembolic and hemorrhagic events following a second dose of ChAdOx1 and BNT162b2 using a self-controlled case series analysis. We used a national prospective cohort with 2.0 million(m) adults vaccinated with two doses of ChAdOx or 1.6 m with BNT162b2...

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Main Authors: Simpson, CR, Kerr, S, Katikireddi, SV, McCowan, C, Ritchie, LD, Pan, J, Stock, SJ, Rudan, I, Tsang, RSM, de Lusignan, S, Hobbs, FDR, Akbari, A, Lyons, RA, Robertson, C, Sheikh, A
Format: Journal article
Language:English
Published: Springer Nature 2022
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author Simpson, CR
Kerr, S
Katikireddi, SV
McCowan, C
Ritchie, LD
Pan, J
Stock, SJ
Rudan, I
Tsang, RSM
de Lusignan, S
Hobbs, FDR
Akbari, A
Lyons, RA
Robertson, C
Sheikh, A
author_facet Simpson, CR
Kerr, S
Katikireddi, SV
McCowan, C
Ritchie, LD
Pan, J
Stock, SJ
Rudan, I
Tsang, RSM
de Lusignan, S
Hobbs, FDR
Akbari, A
Lyons, RA
Robertson, C
Sheikh, A
author_sort Simpson, CR
collection OXFORD
description We investigated thrombocytopenic, thromboembolic and hemorrhagic events following a second dose of ChAdOx1 and BNT162b2 using a self-controlled case series analysis. We used a national prospective cohort with 2.0 million(m) adults vaccinated with two doses of ChAdOx or 1.6 m with BNT162b2. The incidence rate ratio (IRR) for idiopathic thrombocytopenic purpura (ITP) 14-20 days post-ChAdOx1 second dose was 2.14, 95% confidence interval (CI) 0.90-5.08. The incidence of ITP post-second dose ChAdOx1 was 0.59 (0.37-0.89) per 100,000 doses. No evidence of an increased risk of CVST was found for the 0-27 day risk period (IRR 0.83, 95% CI 0.16 to 4.26). However, few (≤5) events arose within this risk period. It is perhaps noteworthy that these events all clustered in the 7-13 day period (IRR 4.06, 95% CI 0.94 to 17.51). No other associations were found for second dose ChAdOx1, or any association for second dose BNT162b2 vaccination. Second dose ChAdOx1 vaccination was associated with increased borderline risks of ITP and CVST events. However, these events were rare thus providing reassurance about the safety of these vaccines. Further analyses including more cases are required to determine more precisely the risk profile for ITP and CVST after a second dose of ChAdOx1 vaccine.
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spelling oxford-uuid:bdb7338c-318b-4d40-8f33-5bcd263e27402022-10-14T15:39:50ZSecond-dose ChAdOx1 and BNT162b2 COVID-19 vaccines and thrombocytopenic, thromboembolic and hemorrhagic events in ScotlandJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:bdb7338c-318b-4d40-8f33-5bcd263e2740EnglishSymplectic ElementsSpringer Nature2022Simpson, CRKerr, SKatikireddi, SVMcCowan, CRitchie, LDPan, JStock, SJRudan, ITsang, RSMde Lusignan, SHobbs, FDRAkbari, ALyons, RARobertson, CSheikh, AWe investigated thrombocytopenic, thromboembolic and hemorrhagic events following a second dose of ChAdOx1 and BNT162b2 using a self-controlled case series analysis. We used a national prospective cohort with 2.0 million(m) adults vaccinated with two doses of ChAdOx or 1.6 m with BNT162b2. The incidence rate ratio (IRR) for idiopathic thrombocytopenic purpura (ITP) 14-20 days post-ChAdOx1 second dose was 2.14, 95% confidence interval (CI) 0.90-5.08. The incidence of ITP post-second dose ChAdOx1 was 0.59 (0.37-0.89) per 100,000 doses. No evidence of an increased risk of CVST was found for the 0-27 day risk period (IRR 0.83, 95% CI 0.16 to 4.26). However, few (≤5) events arose within this risk period. It is perhaps noteworthy that these events all clustered in the 7-13 day period (IRR 4.06, 95% CI 0.94 to 17.51). No other associations were found for second dose ChAdOx1, or any association for second dose BNT162b2 vaccination. Second dose ChAdOx1 vaccination was associated with increased borderline risks of ITP and CVST events. However, these events were rare thus providing reassurance about the safety of these vaccines. Further analyses including more cases are required to determine more precisely the risk profile for ITP and CVST after a second dose of ChAdOx1 vaccine.
spellingShingle Simpson, CR
Kerr, S
Katikireddi, SV
McCowan, C
Ritchie, LD
Pan, J
Stock, SJ
Rudan, I
Tsang, RSM
de Lusignan, S
Hobbs, FDR
Akbari, A
Lyons, RA
Robertson, C
Sheikh, A
Second-dose ChAdOx1 and BNT162b2 COVID-19 vaccines and thrombocytopenic, thromboembolic and hemorrhagic events in Scotland
title Second-dose ChAdOx1 and BNT162b2 COVID-19 vaccines and thrombocytopenic, thromboembolic and hemorrhagic events in Scotland
title_full Second-dose ChAdOx1 and BNT162b2 COVID-19 vaccines and thrombocytopenic, thromboembolic and hemorrhagic events in Scotland
title_fullStr Second-dose ChAdOx1 and BNT162b2 COVID-19 vaccines and thrombocytopenic, thromboembolic and hemorrhagic events in Scotland
title_full_unstemmed Second-dose ChAdOx1 and BNT162b2 COVID-19 vaccines and thrombocytopenic, thromboembolic and hemorrhagic events in Scotland
title_short Second-dose ChAdOx1 and BNT162b2 COVID-19 vaccines and thrombocytopenic, thromboembolic and hemorrhagic events in Scotland
title_sort second dose chadox1 and bnt162b2 covid 19 vaccines and thrombocytopenic thromboembolic and hemorrhagic events in scotland
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