Table 1.
Reported thrombocytopenic, venous and arterial thromboembolic and hemorrhagic events for the ChAdOx1 vaccine
| Time period after vaccination | Number of individualsa | Number of eventsb | Unadjusted RR (95% CI) | Number of risk groups adjusted RR (95% CI) | Fully adjusted RR (95% CI)c |
|---|---|---|---|---|---|
| Thrombocytopenia (excluding ITP) | |||||
| Unvaccinated | 2,343 | 207 (8.8%) | 1.00 (1.00–1.00) | 1.00 (1.00–1.00) | 1.00 (1.00–1.00) |
| 0–6 d | 101 | 18 (17.8%) | 3.54 (1.76–7.10) | 2.76 (1.36–5.60) | 2.80 (1.39–5.67) |
| 7–13 d | 127 | 8 (6.3%) | 0.71 (0.28–1.77) | 0.66 (0.27–1.60) | 0.69 (0.29–1.67) |
| 14–20 d | 95 | 10 (10.5%) | 1.55 (0.66–3.66) | 1.12 (0.47–2.65) | 1.20 (0.49–2.90) |
| 21–27 d | 91 | 10 (11.0%) | 1.86 (0.75–4.58) | 1.34 (0.55–3.28) | 1.26 (0.51–3.14) |
| 28+ d | 407 | 48 (11.8%) | 2.15 (1.18–3.94) | 1.55 (0.84–2.88) | 1.53 (0.82–2.87) |
| 0–27 d | 414 | 46 (11.1%) | 1.82 (1.09–3.03) | 1.40 (0.84–2.32) | 1.42 (0.86–2.37) |
| ITP | |||||
| Unvaccinated | 702 | 58 (8.3%) | 1.00 (1.00–1.00) | 1.00 (1.00–1.00) | 1.00 (1.00–1.00) |
| 0–6 d | 35 | ≤5 (≤14.3%) | 3.95 (1.08–14.52) | 3.16 (0.82–12.19) | 3.43 (0.88–13.33) |
| 7–13 d | 51 | 7 (13.7%) | 4.51 (1.42–14.31) | 4.31 (1.32–14.05) | 4.60 (1.37–15.42) |
| 14–20 d | 39 | 7 (17.9%) | 8.50 (2.53–28.57) | 8.62 (2.55–29.07) | 7.81 (2.28–26.71) |
| 21–27 d | 17 | ≤5(≤29.4%) | 14.75 (2.67–81.51) | 13.85 (2.44–78.62) | 14.07 (2.46–80.31) |
| 28+ d | 48 | ≤5 (≤10.4%) | 1.50 (0.27–8.19) | 1.29 (0.22–7.54) | 1.25 (0.21–7.46) |
| 0–27 d | 142 | 23 (16.2%) | 6.01 (2.56–14.07) | 5.67 (2.39–13.46) | 5.77 (2.41–13.83) |
| Venous thromboembolic events (including CVST) | |||||
| Unvaccinated | 26,843 | 2,449 (9.1%) | 1.00 (1.00–1.00) | 1.00 (1.00–1.00) | 1.00 (1.00–1.00) |
| 0–6 d | 952 | 92 (9.7%) | 1.13 (0.87–1.46) | 0.97 (0.75–1.25) | 0.96 (0.74–1.24) |
| 7–13 d | 1,074 | 101 (9.4%) | 1.15 (0.89–1.49) | 0.95 (0.73–1.22) | 0.91 (0.71–1.18) |
| 14–20 d | 1,131 | 130 (11.5%) | 1.61 (1.26–2.05) | 1.30 (1.02–1.65) | 1.23 (0.96–1.57) |
| 21–27 d | 953 | 100 (10.5%) | 1.52 (1.16–2.00) | 1.17 (0.89–1.54) | 1.10 (0.84–1.44) |
| 28+ d | 3,616 | 381 (10.5%) | 1.58 (1.30–1.93) | 1.20 (0.98–1.47) | 1.08 (0.88–1.32) |
| 0–27 d | 4,110 | 423 (10.3%) | 1.32 (1.13–1.54) | 1.08 (0.92–1.26) | 1.03 (0.89–1.21) |
| Arterial thromboembolic events | |||||
| Unvaccinated | 67,599 | 5,937 (8.8%) | 1.00 (1.00–1.00) | 1.00 (1.00–1.00) | 1.00 (1.00–1.00) |
| 0–6 d | 3,211 | 303 (9.4%) | 1.26 (1.09–1.46) | 1.08 (0.94–1.26) | 1.08 (0.93–1.25) |
| 7–13 d | 3,333 | 344 (10.3%) | 1.54 (1.34–1.78) | 1.26 (1.09–1.46) | 1.25 (1.08–1.44) |
| 14–20 d | 3,352 | 350 (10.4%) | 1.68 (1.45–1.95) | 1.29 (1.11–1.50) | 1.26 (1.09–1.46) |
| 21–27 d | 3,261 | 351 (10.8%) | 1.89 (1.62–2.19) | 1.40 (1.20–1.62) | 1.37 (1.18–1.60) |
| 28+ d | 13,925 | 1,477 (10.6%) | 2.03 (1.81–2.27) | 1.37 (1.23–1.54) | 1.33 (1.19–1.50) |
| 0–27 d | 13,157 | 1,348 (10.2%) | 1.55 (1.41–1.70) | 1.24 (1.13–1.36) | 1.22 (1.12–1.34) |
| Hemorrhagic events | |||||
| Unvaccinated | 8,972 | 785 (8.7%) | 1.00 (1.00–1.00) | 1.00 (1.00–1.00) | 1.00 (1.00–1.00) |
| 0–6 d | 337 | 32 (9.5%) | 1.39 (0.87–2.20) | 1.22 (0.78–1.93) | 1.08 (0.68–1.73) |
| 7–13 d | 350 | 44 (12.6%) | 2.22 (1.47–3.37) | 1.96 (1.29–2.98) | 1.87 (1.23–2.84) |
| 14–20 d | 324 | 38 (11.7%) | 2.09 (1.33–3.27) | 1.80 (1.15–2.82) | 1.67 (1.07–2.62) |
| 21–27 d | 314 | 35 (11.1%) | 1.84 (1.16–2.89) | 1.53 (0.97–2.42) | 1.42 (0.90–2.25) |
| 28+ d | 1,316 | 129 (9.8%) | 1.51 (1.06–2.14) | 1.18 (0.82–1.68) | 1.10 (0.77–1.57) |
| 0–27 d | 1,325 | 149 (11.2%) | 1.86 (1.41–2.45) | 1.60 (1.21–2.12) | 1.48 (1.12–1.96) |
aNumber of individuals in the vaccine exposure group. bNumber of events is the number of individuals with an incident consultation in the post-vaccination period. Percent is the number of events divided by n and should be equal to 8.34% if there is no association between vaccination and the event representing the 10:1 ratio of controls to cases. cAdjusted for number of clinical risk group, socioeconomic status and number of RT–PCR tests an individual had before 8 December 2020. n ≤ 5 denotes minimum allowable reported value.