THU0568 EFFECTIVENESS OF FOOT ORTHOSIS TO PROMOTE PHYSICAL ACTIVITY FOR PATIENTS WITH CONCURRENT RHEUMATOID ARTHRITIS AND SARCOPENIA
Authors: N. Hishikawa, S. Toyama, S. Ohashi, K. Sawada, K. Ikoma, D. Tokunaga, Y. Mikami
Journal: Annals of the Rheumatic Diseases (2020)

Background: Sarcopenia is a progressive systemic skeletal muscle disorder associated with an increased likelihood of adverse outcomes including physical disability, falls, and mortality. The muscle mass of patients with rheumatoid arthritis (RA) is lower than that of age-matched healthy individuals, and a high prevalence rate of sarcopenia has been reported 1) . In particular, foot deformities may increase the prevalence rate of sarcopenia because of inactivity due to foot pain on walking. Treatment with a foot orthosis (FO) can reportedly reduce pain 2) ; however, whether a FO can resolve inactivity and sarcopenia is unclear. Objectives: To elucidate the effectiveness of a FO on physical activity and sarcopenia in patients with RA. Methods: Thirty patients with RA with foot deformities were enrolled from April 2017 to December 2019. Sarcopenia was diagnosed using the algorithm of the European Working Group on Sarcopenia in Older People, and the cut-off values of the Asian Working Group for Sarcopenia were applied. We also collected the clinical variables of patients with concurrent RA and sarcopenia who continued to use a FO for 6 months. The primary outcome was physical activity determined by the International Physical Activity Questionnaire. The secondary outcomes were foot pain measured with a visual analog scale; activities of daily living (ADL) measured with the Health Assessment Questionnaire; and body mass index, body fat percentage, and the skeletal muscle mass index measured with a body composition device. The clinical variables were compared between baseline and 6 months after continuous treatment with a FO. Results: The prevalence rate of sarcopenia was 76.6% (23/30), and nine patients with RA continued to use the FO for 6 months. Table 1 shows outcomes at baseline and after 6 months of treatment with a FO. The only clinical variable that showed a significant difference was foot pain. Physical activities, ADL, and body compositions were maintained after 6 months. Table 1. Outcomes of 6-month treatment with FO Baseline 6 months p value Physical activity IPAQ Walking, MET-min/week Moderate, MET-min/week Vigorous, MET-min/week 132 (66, 594) 0 (0, 0) 0 (0, 0) 594 (396, 2376) 0 (0, 0) 0 (0, 0) 0.07 1.00 0.32 Foot pain VAS score 4.6 (3.1, 7.4) 2.8 (1.1, 4.7) 0.02 ADL HAQ 1.5 (1.1, 2.3) 1.1 (0.9, 1.5) 0.07 Body composition BMI, kg/m 2 BFP, % SMI, kg/m 2 21.4 (20.7, 22.7) 31.1 (24.2, 37.6) 5.2 (4.8, 5.3) 20.7 (19.3, 22.1) 32.9 (26.3, 36.5) 5.2 (5.0, 5.2) 0.89 0.82 0.61 IPAQ: International Physical Activity Questionnaire, VAS: visual analog scale, ADL: activities of daily living, HAQ: Health Assessment Questionnaire, BMI: body mass index, BFP: body fat percentage, SMI: skeletal muscle mass index Data are presented as median (lower quartile, upper quartile) Conclusion: The prevalence rate of sarcopenia in patients with RA with foot deformities was much higher than previous reported 1) . However, 6 months of treatment with a FO not only reduced foot pain but also maintained physical activity and muscle mass. Physical therapy has recently been recommended for patients with inflammatory arthritis. physical activity and muscle mass of patients with RA and concurrent foot deformities may be increased by combining physical therapy with orthotic treatment. References: [1]Tada M, et al. Matrix metalloprotease 3 is associated with sarcopenia in rheumatoid arthritis - results from the CHIKARA study. Int J Rheum Dis. 2018; 21 (11): 1962-9. [2]Hennessy K, et al. Custom foot orthoses for rheumatoid arthritis: A systematic review. Arthritis Care Res (Hoboken). 2012; 64 (3): 311-20. Acknowledgments: This work was supported by JSPS KAKENHI Grant Numbers JP19K11420. Disclosure of Interests: None declared DOI: 10.1136/annrheumdis-2020-eular.3143