Abstract
Rheumatoid arthritis (RA), the commonest inflammatory arthritis, is a debilitating disease leading to decreased functional capacity, social disability and reduced quality of life. RA affects multisystems with chronic inflammatory disease characterized by destructive synovitis and muscular dysfunction leading to premature musculoskeletal aging, which has been coined with many terms including myopenia, sarcopenia, cachexia, muscle failure and muscle wasting. Myopenia is described as the presence of clinically relevant muscle wasting due to any illness at any age, associated with impaired muscle function, increased morbidity and mortality. RA myopenia has significantly less muscle mass compared to the general population muscle loss showing preservation or slight increase in fat mass. RA myopenia is unique compared to chronic disease-related myopenia in cancer, chronic heart failure, kidney disease and chronic infection as it is rarely accompanied by a net weight loss. RA myopenia has younger-age onset compared to elderly primary sarcopenia, while higher-grade inflammation has been considered as the pathophysiology of muscle wasting. Research, however, indicates that inflammation itself cannot fully explain the high prevalence of muscle wasting in RA. This chapter aims to review the literature on the casual relationships among RA myopenia, premature musculoskeletal aging and management strategies to delay musculoskeletal aging.