Table 5.
HRs of infection outcomes by vaccination status
| Outcome | No RA (n = 3699) | RA (n = 3699) | ||
|---|---|---|---|---|
| Not vaccinated | Vaccinated | Not vaccinated | Vaccinated | |
| Pneumonia vaccinations, n (%) | 3239 (88) | 460 (12) | 3093 (84) | 606 (16) |
| Pneumonia events, n (%) | 30 (1) | 12 (3) | 88 (3) | 20 (3) |
| Exposure time, person-years | 14 401 | 2032 | 12 780 | 2601 |
| Event rate per 1000 person-years, median (IQR) | 2.1 (1.4–3.0) | 5.9 (3.1–10.3) | 6.9 (5.5–8.5) | 7.7 (4.7–11.9) |
| Unadjusted HR (95% CI) | Reference | 2.84 (1.45, 5.54) | Reference | 1.12 (0.69, 1.82) |
| Adjusted HR (95% CI)a | Reference | 2.03 (1.00, 4.11) | Reference | 0.90 (0.55, 1.48) |
| Influenza vaccinations, n (%) | 1920 (52) | 1779 (48) | 1348 (36) | 2351 (64) |
| Influenza-like illness events, n (%) | 57 (3) | 34 (2) | 35 (3) | 42 (2) |
| Exposure time, person-years | 8484 | 7842 | 4951 | 10383 |
| Event rate per 1000 person-years, median (IQR) | 6.7 (5.1–8.7) | 4.3 (3.0–6.1) | 7.1 (4.9–9.8) | 4.0 (2.9–5.5) |
| Unadjusted HR (95% CI) | Reference | 0.65 (0.42, 0.99) | Reference | 0.58 (0.37, 0.90) |
| Adjusted HR (95% CI)a | Reference | 0.95 (0.55, 1.64) | Reference | 0.59 (0.36, 0.98) |
a
Adjusted for age, sex, ethnicity (white/missing or non-white), BMI category (<18.5 underweight, 18.5–24.9 normal weight, 25.0–29.9 overweight, 30.0–34.9 class I obesity, 35.0–39.9 class II obesity, ≥40.0 class III obesity, missing), smoking status (never, current, former, missing), comorbidities (COPD, asthma, diabetes, CKD), use of immunosuppressive agents and, in those with RA, the duration of RA and seropositivity (presence of RF or anti-CCP antibodies.