Risk of infection requiring hospitalization in patients with rheumatoid arthritis (RA) compared to non-RA controls.
| Study | Year | Design | Sample, n patients | Non-RA Comparator | Duration | Adjustments | Outcome | Incidence (per 100 PY) | RR (95% CI) | |
|---|---|---|---|---|---|---|---|---|---|---|
| RA Cohort | Non-RA Cohort | |||||||||
| Doran3 | 2002 | Retrospective cohort | 609 RA | 609 matched controls | 1955–1994 | Age, sex, smoking status, leukopenia, corticosteroid use, diabetes mellitus | Objectively confirmed infections | 19.64 | 12.87 | 1.7 (1.4–2.0) |
| Infections requiring hospitalization | 9.57 | 5.09 | 1.8 (1.5–2.2) | |||||||
| Any documented infection | 32.05 | 24.04 | 1.5 (1.3–1.6) | |||||||
| Franklin4 | 2007 | Prospective cohort | 2108 with new onset inflammation polyarthritis | UK general population | 1990–1999 | Age, sex | Infections requiring hospitalization | 1.21 | NR* | 2.7 (2.0–3.4) |
| Respiratory | 0.59 | NR* | 3.5 (2.3–5.4) | |||||||
| Urinary tract | 0.28 | NR* | 2.0 (1.2–3.4) | |||||||
| Skin | 0.19 | NR* | 1.9 (1.1–3.0) | |||||||
| Septicemia | 0.09 | NR* | 4.0 (2.0–7.8) | |||||||
| Smitten2 | 2008 | Retrospective cohort | 24,530 RA | 500,000 randomly selected non-RA pts | 1999–2006 | Age, sex, calendar year of entry, prescription medication use at cohort entry, no. comorbid conditions prior to cohort entry | Infections requiring hospitalization | 3.86 | 1.25 | 2.0 (1.9–2.1) |
↵* Incidence rates in the RA population were compared with expected rates calculated from 10-year age, sex, and calendar year-specific hospitalization rates obtained from the regional population. PY: patient-years; NR: not reported.