TY - JOUR
AU - Simpson, Colin R.
AU - Kerr, Steven
AU - Katikireddi, Srinivasa Vittal
AU - McCowan, Colin
AU - Ritchie, Lewis D.
AU - Pan, Jiafeng
AU - Stock, Sarah J.
AU - Rudan, Igor
AU - Tsang, Ruby S. M.
AU - de Lusignan, Simon
AU - Hobbs, F.D. Richard
AU - Akbari, Ashley
AU - Lyons, Ronan A.
AU - Robertson, Chris
AU - Sheikh, Aziz
PY - 2022
DA - August
TI - Second-dose ChAdOx1 and BNT162b2 COVID-19 vaccines and thrombocytopenic, thromboembolic and hemorrhagic events in Scotland
JO - Nature Communications
VL - 13
IS - 1
DO - https://doi.org/10.1038/s41467-022-32264-6
AB - 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.
PB - Springer Nature
UR - http://hdl.handle.net/10023/25855
KW - Coronavirus (COVID-19)
KW - Immunisation and screening
ER