Observed incidence rates (IR) and IR ratio (IRR with 95% CI) overall and by primary infection site in the lookback period in patients with immunoglobulin A vasculitis (IgAV) and controls.
| IgAV, n = 314 | Controls, n = 982 | Rate/OR | p | |
|---|---|---|---|---|
| Lookback time, mos | 11.9 (0–48) | 16.9 (1–58) | 0.11 | |
| Patients with infections, n (%) | 36 (11.5) | 93 (9.7) | 1.23 (0.79–1.88) | 0.32 |
| Total person-mos observation | 16,890 | 54,275 | — | |
| Total infections | 83 | 195 | — | |
| IR/1000 person-mos | 4.91 | 3.6 | 1.37 (1.06–0.77) | 0.009 |
| Infection type | N, IR (95% CI) | N, IR (95% CI) | IRR | |
| Laryngitis/pharyngitis | 5, 0.28 (0.09–0.69) | < 5, 0.01 (0.002–0.10) | 16.07 (2.25–382) | < 0.001 |
| Upper respiratory tract | 92, 5.45 (4.39–6.68) | 165, 3.04 (2.59–3.51) | 1.79 (1.39–2.31) | < 0.001 |
| Pneumonia | — | — | — | |
| Skin/soft tissue | 6, 0.36 (0.12–0.77) | 19, 0.35 (0.11–0.50) | 1.01 (0.37–2.46) | 0.9 |
| Urinary tract | < 5, 0.12 (0.001–0.78) | 5, 0.09 (0.02–0.21) | 1.29 (0.17–6.51) | 0.76 |
| Sepsis/bacteremia | 0 | — | < 5, 0.28 (0.09–0.69) | — |
Small numbers (n < 5) were made confidential following requirements of the Human Research Ethics Committee at the Western Australia Department of Health.