The Efficacy of Biological Disease-modifying Antirheumatic Drugs on Sarcopenia in Patients with Rheumatoid Arthritis

Objective Sarcopenia is characterized by a loss of muscle mass and strength, which leads to frailty and mortality. Rheumatoid arthritis (RA) is considered to be a cause of sarcopenia. The present study assessed the effectiveness of biological disease-modifying antirheumatic drugs (bDMARDs) on sarcopenia. Methods This was a prospective cohort study including 48 patients [11 men, 37 women; 67.5 (57.0-74.8) years old] with RA who started bDMARDs in Niigata Rheumatic Center. We monitored the physical ability, nutritional status and body composition at the baseline, 6 months and 12 months. The physical activity was measured by the Health Assessment Questionnaire (HAQ) and 10-m walking test (10MWT). The nutritional status was assessed by the controlling nutrition status (CONUT) score. Results Among the 48 patients who started bDMARDs, 21 were classified as having sarcopenia. The physical activity and nutritional status were significantly ameliorated after 12 months of bDMARDs. The body composition analysis showed a significant increase in the body weight but no significant increase in the skeletal muscle mass index. The proportion of patients diagnosed with sarcopenia decreased significantly after 12 months of bDMARDs (43.8% vs. 27.1%, p=0.039). Among the 21 patients who were diagnosed with sarcopenia when starting bDMARDs, the skeletal muscle index was significantly increased after 12 months of bDMARDs. [5.22 (4.76-5.43) kg/m² vs. 5.44 (4.84-5.77), p=0.039]. Conclusion Biologics may be useful in the treatment of sarcopenia through mechanisms such as improving the disease activity, physical activity and nutritional status.