AB0609 COMPARISON OF PHYSICAL FUNCTION AND BODY COMPOSITION BETWEEN ELDERLY RHEUMATOID ARTHRITIS PATIENTS AND HEALTHY CONTROLS
Authors: T. Sugiura, M. Suzuki, H. Sugiura, Y. Saito, H. Yamamoto, K. Terabe, H. Kosugiyama, R. Sato, J. Hasegawa, Y. Ohno, S. Asai, S. Imagama
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> The aging of patients with rheumatoid arthritis (RA) has been reported in recent years,(1) and RA not only causes joint symptoms but also affects physical function(2), especially in the elderly, which is a more serious problem than in healthy controls. However, few studies have compared body composition and exercise capacity between healthy controls and RA patients. <h3>Objectives:</h3> In this study, we investigated the differences in physical function and body composition between RA patients and healthy controls by comparing the results of general health check-ups in a local city with those of RA patients in our hospital. <h3>Methods:</h3> Between March 2021 and December 2022, a total of 904 subjects (328 in the RA group and 576 in the health check-up group) participated in the Fairy Study, a prospective cohort study of frailty in RA patients, and 490 women aged 60 years or older participated in the functional check-up for the elderly in Togo City, Aichi Prefecture. The subjects were 490 women aged 60 years or older. Bioelectrical impedance (BIA) and motor function tests were performed to measure muscle mass using SMI and muscle quality using PhA. Motor function was measured by grip strength, which reflects upper limb muscle strength, and 10 m walking speed and standing test, which reflect lower limb muscle strength. Age and body mass index (BMI) at enrolment were used as covariates, and a propensity score was calculated using logistic regression for comparison. <h3>Results:</h3> Propensity score matching for age and BMI was performed on a total of 490 subjects (307 in the non-RA group and 183 in the RA group), and a total of 308 subjects were selected. The RA group (n=154) was a low disease activity patient group with disease duration of 11.0 (9.6) years, DAS28-ESR of 2.32 (1.04), and HAQ-DI of 0.45 (0.46). The mean age of the non-RA and RA groups was 72.2(4.2)/72.2(4.3) years and BMI was 21.62(2.9)/21.8(3.7) kg/m<sup>2</sup>.Grip strength was 23.7(4.5)/20.0(8.7) kg/5 stand-up test (SS-5) was 8.7(2.1)/11.9(4.7), a significant difference. (p&lt;0.0001) walking speed 1.6 (1.0)/1.4 (1.5) seconds, but no significant difference was found. SMI, an index of muscle mass, was 6.1 (0.6)/6.0 (1.1), not significantly different between the two groups, but phase angle (PhA), an index of muscle quality, was 4.7 (0.56)/4.5 (0.72), a significant difference (p=0.0077). <h3>Conclusion:</h3> Compared with non-RA, female elderly RA patients had significantly lower motor function and lower muscle quality despite no significant difference in muscle mass. <h3>REFERENCES:</h3> [1] Kato E, Sawada T, Tahara K, Hayashi H, Tago M, Mori H, et al.: The age at onset of rheumatoid arthritis is increasing in Japan: a nationwide database study. Int J Rheum Dis 2017;20:839-45 [2] Alamanos Y, Voulgari PV, Drosos AA. Incidence and prevalence of rheumatoid arthritis, based on the 1987 American College of Rheumatology criteria: a systematic review. Semin Arthritis Rheum. 2006;36:182–188 <h3>Acknowledgements:</h3> I would like to thank the Mayor of Togo Township and all of its officials for their support in conducting this study. <h3>Disclosure of Interests:</h3> <b>None declared.</b>