Relative risk (RR) including 95% confidence intervals (CI) of malignant lymphoma in one prevalent cohort, one incident cohort, and one TNF antagonist treated cohort, respectively, of Swedish patients with RA
| Covariate | Person-years | Lymphomas (n) | Relative risk (95% CI) |
|---|---|---|---|
| RRs estimated using Poisson regression, adjusted for all parameters in table. | |||
| *Counting from date of first discharge with RA (Inpatient Register RA cohort) or specified date of onset of RA (Early Arthritis Register and TNF antagonist cohort). | |||
| RA cohort | |||
| Inpatient register cohort | 297102 | 319 | 1.0 (reference) |
| Cohort with early arthritis | 13292 | 11 | 0.8 (0.4 to 1.4) |
| TNF antagonist cohort | 9715 | 9 | 1.1 (0.6 to 2.1) |
| Sex | |||
| Male | 82596 | 138 | 2.0 (1.6 to 2.4) |
| Female | 237513 | 201 | 1.0 (reference) |
| Age at entry (years) | |||
| 16–44 | 27702 | 9 | 1.0 (reference) |
| 45–74 | 190631 | 197 | 3.1 (1.6 to 6.1) |
| 75+ | 101776 | 133 | 4.1 (2.1 to 8.0) |
| Time with RA* (years) | |||
| Missing | 437 | 0 | – |
| 0–4 | 137053 | 159 | 0.9 (0.6 to 1.1) |
| 5–9 | 73708 | 73 | 0.8 (0.7 to 1.1) |
| 10+ | 108911 | 107 | 1.0 (reference) |