Table 2 Incident rate ratiosa, with 95% confidence intervals (CIs) for cardiovascular eventsa following pandemic influenza vaccination (pandemrix) among higher risk individuals defined on the basis of medication use
AMI (n = 5032) | Stroke (n = 3129) | Pulmonary Embolism (n = 859) | |||||||
|---|---|---|---|---|---|---|---|---|---|
No. of events | Person-days at risk | IRR (95% CI)b | No. of events | Person-days at risk | IRR (95% CI)b | No. of events | Person-days at risk | IRR (95% CI)b | |
Baseline perioda | 3368 | 1,635,876 | 1.00 (ref.) | 2061 | 1,017,036 | 1.00 (ref.) | 564 | 279,612 | 1.00 (ref.) |
Pre-vaccination interval | |||||||||
1–14 days | 124 | 70,686 | 0.85 (0.70–1.02) | 55 | 43,946 | 0.66 (0.50–0.87) | 30 | 12,082 | 1.23 (0.83–1.81) |
On the day of vaccination | 3 | 5049 | 0.29 (0.09–0.89) | 3 | 3139 | 0.50 (0.16–1.56) | 0 | 863 | No estimates |
Post vaccination interval | |||||||||
1–14 days | 105 | 70,686 | 0.72 (0.59–0.88) | 64 | 43,946 | 0.77 (0.59–0.99) | 18 | 12,082 | 0.73 (0.45–1.19) |
15–28 days | 101 | 70,686 | 0.70 (0.57–0.85) | 80 | 43,946 | 0.96 (0.76–1.22) | 22 | 12,082 | 0.89 (0.57–1.38) |
29–59 days | 277 | 156,519 | 0.88 (0.77–1.00) | 181 | 97,309 | 0.99 (0.84–1.18) | 49 | 26,753 | 0.86 (0.62–1.20) |
60–90 days | 261 | 156,519 | 0.87 (0.73–1.04) | 171 | 97,309 | 0.96 (0.77–1.20) | 39 | 26,753 | 0.65 (0.42–1.00) |
91–120 days | 293 | 141,470 | 1.01 (0.85–1.20) | 167 | 94,170 | 0.96 (0.78–1.19) | 49 | 25,890 | 0.84 (0.56–1.26) |
121–180 days | 500 | 302,940 | 0.82 (0.74–0.91) | 347 | 188,340 | 0.92 (0.82–1.04) | 88 | 51,780 | 0.81 (0.63–1.04) |