Table 2. Association of History of High-Risk Allergy With Self-reported Allergic Reactions Over 3 Days After mRNA COVID-19 Vaccination.
| Allergic reaction | High-risk allergy history, No. (%) | Relative risk (95% CI) | ||
|---|---|---|---|---|
| With (n = 474) | Without (n = 52 524) | Unadjusted | Adjusteda | |
| Either dose 1 or dose 2 b | ||||
| No. (%) | 55 (11.6) | 2461 (4.7) | 2.48 (1.93-3.18) | 2.46 (1.92-3.16) |
| Itching or rashc | 32 (6.8) | 1390 (2.7) | 2.55 (1.82-3.58) | 2.46 (1.76-3.45) |
| Hives | 16 (3.4) | 460 (0.9) | 3.85 (2.36-6.29) | 3.81 (2.33-6.22) |
| Respiratory symptomsd | 10 (2.1) | 677 (1.3) | 1.64 (0.88-3.04) | 1.76 (0.95-3.27) |
| Angioedema | 13 (2.7) | 329 (0.6) | 4.38 (2.53-7.56) | 4.36 (2.52-7.54) |
| Dose 1 e | ||||
| No. (%) | 34 (7.2) | 964 (1.8) | 3.91 (2.81-5.44) | 3.66 (2.63-5.10) |
| Itching or rashc | 22 (4.6) | 714 (1.4) | 3.41 (2.26-5.17) | 3.16 (2.09-4.79) |
| Hives | 11 (2.3) | 211 (0.4) | 5.78 (3.17-10.52) | 5.47 (3.00-9.99) |
| Respiratory symptomsd | 9 (1.9) | 306 (0.6) | 3.26 (1.69-6.28) | 3.24 (1.68-6.26) |
| Angioedema | 10 (2.1) | 169 (0.3) | 6.56 (3.49-12.33) | 6.33 (3.35-11.95) |
| Dose 2 f , g | ||||
| No. (%) | 19 (4.3) | 1048 (2.0) | 2.09 (1.34-3.26) | 2.10 (1.35-3.28) |
| Itching or rashc | 14 (3.2) | 755 (1.5) | 2.14 (1.27-3.59) | 2.15 (1.28-3.62) |
| Hives | 6 (1.4) | 258 (0.5) | 2.68 (1.20-5.99) | 2.81 (1.26-6.28) |
| Respiratory symptomsd | 3 (0.7) | 385 (0.8) | 0.90 (0.29-2.78) | 1.05 (0.34-3.25) |
| Angioedema | 3 (0.7) | 170 (0.3) | 2.03 (0.65-6.34) | 2.15 (0.69-6.72) |
Abbreviation: mRNA, messenger RNA.
Adjusted for sex, age, race, vaccine manufacturer, and Charlson comorbidity index score.
n = 140 with reported severe allergic reaction, including 6 with high-risk allergy history. Severe allergic reaction was defined as hives or rash plus respiratory symptoms and/or angioedema.
Itching or rash was specified as other than injection site.
Respiratory symptoms included wheezing, chest tightness, or shortness of breath (eMethods in the Supplement).
n = 68 with reported severe allergic reaction, including 6 with high-risk allergy history.
n = 445 with reported high-risk allergy, and n = 51 261 with no high-risk allergy history who received both doses of mRNA COVID-19 vaccine.
n = 74 with reported severe allergic reaction, including 1 with high-risk allergy history.