Temporal trends in mortality in patients with rheumatoid arthritis: a Danish population-based matched cohort study.

OBJECTIVES: To investigate the 5-year all-cause mortality in patients with RA compared with the general population. METHODS: This was a nationwide population-based matched cohort study. RA patients diagnosed between 1996 and the end of 2015 were identified using administrative heath registries and followed until the end of 2020 allowing 5 years of follow-up. Patients with incident RA were matched 1:5 on year of birth and sex with non-RA individuals from the Danish general population. Time-to-event analyses were performed using the pseudo-observation approach. RESULTS: Compared with matched controls in 1996-2000, the risk difference for RA patients ranged from 3.5% (95% CI 2.7%, 4.4%) in 1996-2000 to -1.6% (95% CI -2.3%, -1.0%) in 2011-15, and the relative risk from 1.3 (95% CI 1.2, 1.4) in 1996-2000 to 0.9 (95% CI 0.8, 0.9) in 2011-15. The age-adjusted 5-year cumulative incidence proportion of death for a 60-year-old RA patient decreased from 8.1% (95% CI 7.3%, 8.9%) when diagnosed in 1996-2000 to 2.9% (95% CI 2.3%, 3.5%) in 2011-15, and for matched controls from 4.6% (95% CI 4.2%, 4.9%) to 2.1% (95% CI 1.9%, 2.4%). Excess mortality persisted in women with RA throughout the study period, while the mortality risk for men with RA in 2011-15 was similar to their matched controls. CONCLUSIONS: Enhanced improvement in mortality was found in RA patients compared with matched controls, but for sex-specific differences excess mortality was only persistent in women with RA.

Risk of second malignant neoplasm and mortality in patients with rheumatoid arthritis treated with biological DMARDs: a Danish population-based cohort study.

OBJECTIVE: To study the risk of a second malignant neoplasm (SMN) and mortality in patients with rheumatoid arthritis (RA) with a history of a primary cancer diagnosis and treated with biological disease-modifying antirheumatic drugs (bDMARD). METHODS: Among patients with RA (n=15 286) registered in the DANBIO Register during 2000-2011, 1678 had a primary cancer according to the Danish Cancer Registry. HRs for SMN and death were calculated. RESULTS: During follow-up there were 279 patients with RA contributing person-years to the bDMARDs use before their primary cancer diagnosis, 220 to the only after, 92 to the both before and after, while 1203 patients with RA contributed to the non-use strata. Ever use of bDMARDs was associated with a HR of 1.11 (95% CI 0.74 to 1.67) for developing a SMN compared with non-use (cancer site adjusted). The HR for death associated with bDMARD use before the primary cancer diagnosis was increased 1.53 (95% CI 1.13 to 2.09). After further adjustment for extent of the primary cancer, the HR for death was 1.20 (95% CI 0.88 to 1.63) for bDMARDs use before cancer, 1.36 (95% CI 0.78 to 2.39) for bDMARD use only after cancer and 1.22 (95% CI 0.70 to 2.13) for use both before and after the cancer. CONCLUSIONS: Among patients with RA with a history of cancer, treatment with bDMARDs was not associated with increased risk of SMN. No clear conclusion can be drawn regarding mortality in bDMARD-treated patients with RA.