Cross-sectional study of clinical features of rheumatoid arthritis in elderly and young onset

BACKGROUND: Based on the age of onset, rheumatoid arthritis (RA) can be classified into elderly-onset RA (EORA) and young-onset RA (YORA), which exhibit significant differences in clinical manifestations, comorbidities, and laboratory findings. Understanding these differences is crucial for the individualized diagnosis and treatment of RA. METHODS: This cross-sectional study included 490 RA patients hospitalized in 2023 at Guanghua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine. Detailed demographic data, clinical characteristics, and laboratory parameters were collected and analyzed using R version 4.4.1 for statistical analysis. RESULTS: EORA patients exhibited a higher incidence of joint deformities and higher DAS28-ESR scores compared with the YORA group, suggesting a potentially greater level of disease activity. Regarding comorbidities, the prevalence of interstitial lung disease, hypertension, and osteoporosis was significantly higher in EORA patients. Laboratory findings showed that ESR, D-dimer, and IgA levels were also significantly elevated in the EORA group compared with YORA patients, while no significant differences were observed between the two groups across the 12 cytokine measurements. In addition, EORA patients displayed higher levels of several activated and suppressive T-cell subsets, whereas YORA patients had higher cytotoxic T-cell levels. However, multivariable regression analysis indicated that these differences were not independently driven by disease-onset classification but were instead primarily associated with age, disease exacerbation, and disease duration. CONCLUSIONS: Significant differences exist among EORA and YORA groups in terms of disease manifestations, comorbidities, and biochemical markers. Future research should further investigate the underlying mechanisms of these differences and assess the long-term outcomes of different treatment approaches.