Mariko Kitahama, Hiroshi Okamoto,Chihiro Terai, Yumi Koseki, Tadashi Sakurai and Naoyuki Kamatani
Objective: To investigate causes of death in Japanese patients with Rheumatoid Arthritis (RA) and whether recent RA treatment has been associated with a decrease in AA-amyloidosis among RA patients.
Methods: Data from records of RA patients autopsied in Japan during 2000-2004 and 1985-1989 were analyzed. Cause of death, age at death, gender, and incidence of amyloidosis were assessed.
Results: The average age at death in the recent RA group was 69.1 years in 817 females and 70.1 years in 408 males. Unlike the general population, RA females died earlier than males. In the past 15 years, a survival rate of RA patients has improved. The leading cause of death of recently diagnosed RA patients was infection (32.8%), respiratory diseases (20.2%), and AA-amyloidosis (11.3%). In comparison with patients surveyed in 1985-1989 this represents an increase in deaths from infection and respiratory diseases, a decrease in deaths from RA itself and renal diseases, and no change in deaths from AA-amyloidosis. In RA, more males died of interstitial lung disease (odds 2.94) and more females died from AA-amyloidosis (odds 3.52).
Conclusion: Cause of death is significantly different in RA patients compared to the general population. Although outcomes of RA patients have been improving, the incidence of AA-amyloidosis remains high in Japan.