Amyloidosis as a cause of death in patients with rheumatoid arthritis

Abstract

Objective: To study amyloidosis as a cause of death along with associated factors and frequency of pre-mortem diagnosis in patients with rheumatoid arthritis (RA) autopsied between 1952 and 1991.

Methods: We studied causes of death in 369 consecutively autopsied RA and 370 autopsied non-RA patients of the same sex, age at death, and year of autopsy. In those RA patients who died from 1973 onwards, we were also able to analyse clinical data: pre-mortem diagnosis of amyloidosis, clinical features of RA, and treatment.

Results: Based on autopsy, amyloidosis was determined as a cause of death in 9.5% of RA and in none of the non-RA patients (p<0.001). In our RA patients, we detected no trend in deaths from amyloidosis between 1952 and 1991. The RA patients dying of amyloidosis died younger than those dying of other causes (p=0.001). During the course of the disease, the RA patients with amyloidosis had: higher erythrocyte sedimentation rate (p=0.002), lower haemoglobin (p<0.001), more frequently proteinuria (p<0.001) and renal failure (p<0.001) than did the rest of the RA patients. Pre-mortem, amyloidosis was diagnosed by biopsy in 65% of the RA patients with amyloidosis as their cause of death.

Conclusion: Amyloidosis may be undetected during the course of RA. Thus, it should be actively searched for in the patients with long-lasting and active disease, especially, if they have proteinuria or renal failure.