Rheumatoid Arthritis and Associated Interstitial Lung Disease Mortality Rates and Trends

Rationale: The burden of rheumatoid arthritis (RA) and RA-associated interstitial lung disease (RA-ILD) in recent years has not been well characterized. Objectives: In this study, we sought to describe RA- and RA-ILD-related mortality rates and trends in the United States from 2005 to 2018, stratified by demographics. Methods: We used the Multiple Cause of Death Database available through the Centers for Disease Control and prevention website, which contains data of all deceased U.S. residents. RAand RA-ILD-related deaths were identified using International Classification of Diseases, 10th Revision, codes. We examined the age-adjusted mortality rates and trends stratified by demographics. Results: RA- and RA-ILD-related mortality rates were higher in women and older age groups. However, the prevalence of ILD was higher in male decedents with RA compared with female decedents with RA (13.3% vs. 8.7%). RA-related mortality rates were the highest in Native American individuals followed by White individuals. Compared with White individuals, Hispanic individuals had lower RA-related mortality rates but higher RA-ILD-related mortality rates. Overall RA-related mortality rates per 1,000,000 population members decreased from 30.6 in 2005 to 22.2 in 2018. RA-related mortality rates declined in both sexes, all races, and all age groups. However, RA-ILD-related mortality rates remained stable in both sexes, all races, and all age groups except for the group aged 65 to 84 years, in which the rates declined. Conclusions: The overall RA-related mortality rates are decreasing; however, RA-ILD-related mortality rates remain stable except in the group aged 65-84 years. This would suggest that therapies for RA and improvement in the management of other comorbidities have improved the overall outcomes in patients with RA but have had limited effect in the subgroup of patients with RA-ILD.