Association and rate ratio of cumulative number of attacks by allergy type
| Variables | Estimate | Relapse rate ratio | 95% CI | P values |
| Any allergy vs NKA | ||||
| Unadjusted | 0.1966 | 1.217 | (1.031 to 1.437) | 0.0204 |
| Adjusted* | 0.1165 | 1.124 | (0.959 to 1.317) | 0.1497 |
| Environmental allergy vs NKA | ||||
| Unadjusted | 0.1892 | 1.208 | (1.008 to 1.448) | 0.0407 |
| Adjusted* | 0.1211 | 1.129 | (0.948 to 1.345) | 0.1754 |
| Food allergy vs NKA | ||||
| Unadjusted | 0.3201 | 1.377 | (1.095 to 1.732) | 0.0062 |
| Adjusted* | 0.2423 | 1.274 | (1.023 to 1.587) | 0.0305 |
| Drug allergy vs NKA | ||||
| Unadjusted | 0.1588 | 1.172 | (0.977 to 1.407) | 0.0879 |
| Adjusted* | 0.0918 | 1.096 | (0.918 to 1.308) | 0.3086 |
*The multivariate model adjusted for sex, age at symptom onset, race (non-white vs white), disease category (progressive vs relapsing), and percentage of time on disease-modifying therapy. Disease duration was used as the offset parameter.
NKA, no known allergy.