Associations of frailty with RA-ILD and poor control of disease activity in patients with rheumatoid arthritis: A multi-center retrospective observational study.

BACKGROUND: This study aimed to investigate factors associated with frailty in rheumatoid arthritis (RA) patients. METHODS: A total of 656 RA patients were evaluated using data from an observational study in 2022. Among these patients, 152 with frailty were assigned to the frailty group, and 504 without frailty were assigned to the non-frailty group. Patient characteristics were compared between the two groups by univariate analysis, and factors associated with frailty were assessed by logistic regression analysis. Patient characteristics were also compared between patients with RA-associated interstitial lung disease (RA-ILD) (n = 102) and those without RA-ILD (n = 554). RESULTS: The frailty group was older (mean: 73.6 vs. 66.8 years) and had a higher DAS28-ESR (3.67 vs. 2.66), a higher HAQ-DI (1.13 vs. 0.32), and a higher rate of RA-ILD (25.0 vs. 12.7 %) than the non-frailty group. Age (OR: 1.03, 95 % CI: 1.01-1.05), HAQ-DI (3.22, 2.28-4.56), DAS28-ESR (1.44, 1.19-1.75), and RA-ILD (2.21, 1.24-3.94) were associated with frailty. RA patients with RA-ILD were older (73.3 vs. 67.5 years) and had a higher DAS28-ESR (3.30 vs. 2.80), a higher HAQ-DI (1.19 vs. 0.32), a higher proportion of frail patients (37.3 vs. 20.6 %), lower MTX use (26.5 vs. 62.9 %), and higher steroid use (44.1 vs. 26.8 %) than those without RA-ILD. CONCLUSIONS: Maintaining reasonable control of disease activity is necessary for RA patients, including those with RA-ILD, to recover from frailty.