AB0561 SARCOPENIA IN RHEUMATOID ARTHRITIS: A LONG-TERM PROSPECTIVE STUDY (2024)

Abstract

Background: Sarcopenia is a generalized disease of skeletal muscle characterized by a reduction in muscle mass, muscle strength, and muscle-specific strength, leading to a decline in physical performance[1]. The systemic effects of rheumatoid arthritis (RA) may contribute to the appearance of sarcopenia independently of age. Cross-sectional studies have demonstrated a prevalence of 24% to 30% of sarcopenia in RA[2]. However, there are very few longitudinal studies, all of short duration, assessing the incidence and impact of sarcopenia in RA patients.

Objectives: To assess sarcopenia in a long-term cohort of RA patients.

Methods: The present prospective cohort study included participants 5 years or older with RA enrolled from the 2015-2016 through 2022-2023. Disease activity was evaluated by DAS28-CRP. Physical Function was assessed by HAQ-DI. Muscle strength was measured by handgrip (Jamar hydraulic dynamometer/kg). Appendicular Skeletal Muscle Mass Index (ASMI/Kg/m²) was measured by dual-energy X-ray absorptiometry (DXA). Physical performance was assessed by Timed up and Go test (seconds). Sarcopenia was assessed by EWGSOP2 criteria. The descriptive analysis, GEE analysis and Kaplan–Meier survival curve were performed (p≤0.05).

Results: A total of 90 RA patients were included with a median follow-up period of 6.4 (5.8-7.0) years. At baseline, the mean age was 56.5±7.3 years, median disease duration was 8.5 (3.0–18.0) years, median DAS28-CRP was 3.0 (1.0–3.0), and mean HAQ-DI was 1.1±0.9. At baseline, only 7 RA patients (7.7%) were diagnosed with sarcopenia, with one having severe sarcopenia. At the end of the follow-up, Sarcopenia persisted in 3 patients, two patients moved to probable sarcopenia, one patient did not follow-up, and one participant moved from severe sarcopenia to sarcopenia. Moreover, no change in the prevalence of sarcopenia was found (p=0.276) and no new sarcopenia during follow-up was observed. Six patients died during the study period: three due to malignancy, one from COVID-19, and two from unknown causes. Baseline sarcopenia was not associated with falls, fractures, or mortality (p>0.05) at the end of follow-up. Conversely, although not statistically significant, patients with low muscle strength exhibited a trend towards a 4.5 times higher relative risk (OR) for mortality

Conclusion: In established RA patients under regular ambulatory care, the prevalence of sarcopenia remained low and stable during the follow-up. In addition, there was not incidence of sarcopenia during follow-up. Baseline sarcopenia did not emerge as a risk factor for falls, fractures, or mortality in established RA patients undergoing regular treatment. On the other hand, patients with low muscle strength presented a trend 3.5 higher risk for mortality. These findings underscore the necessity of integrating routine muscular strength assessment into the daily clinical practice of managing RA patients.

Acknowledgements: NIL.

Disclosure of Interests: None declared.