To determine how the mortality of patients with rheumatoid arthritis (RA) behave in comparison with that of patients with malignant rheumatoid arthritis (MRA).
The mortality of RA patients selected at randam identified in 1991-2000 (n = 104) was compared with that of 18 MRA patients. Hazard ratios of death were calculated with a multivariate survival analysis. A clinical study of patients with both RA and MRA was performed in mortality.
Excess mortality was seen in MRA patients in Kaplan-Meier survival curves (p = 0.02 by log-rank test). MRA patients were treated more often with cytostatic and immunosuppressive drugs. Infection was the main cause of death in both RA and MRA patients. Vasculitis was not reported as the cause of death in MRA patients. Secondary amyloidosis played an important role in RA death rather than MRA.
There remained an excess mortality in MRA patients compared with RA, and infection was attributable to the key cause of death in both RA and MRA suggesting therapeutic side effects.