Unincreased mortality of patients with early rheumatoid arthritis compared to the general population in the past 17 years: Analyses from the IORRA cohort

Objectives The aim of this article is to investigate the mortality rate of patients with early rheumatoid arthritis (RA) over the past 17 years. Methods Japanese patients with early RA enrolled in the Institute of Rheumatology, Rheumatoid Arthritis cohort from 2001 to 2012 were classified into Groups A (2001-06) and B (2007-12). The standardized mortality ratio (SMR) and 5-year survival rate were calculated. Results Groups A and B had 1609 and 1608 patients, of which 167 and 178 patients were lost during follow-up and 47 and 45 deaths were confirmed, respectively. The SMR (95% confidence intervals) for Groups A and B were 0.81 (0.59-1.08) and 0.78 (0.57-1.04), respectively, with the condition that all untraceable patients were alive. Assuming that the mortality rate of untraceable patients was twice as high as that of the general population, the SMR was 0.90 (0.68-1.19) for Group A and 0.92 (0.68-1.23) for Group B. The 5-year survival rates were 96.9% and 97.0% for Groups A and B, respectively. Conclusions The 5-year mortality of patients with early RA has been comparable to that of the general Japanese population. The 5-year survival rate has been stable over the past 17 years.