Bone metabolism in rheumatoid arthritis

In active RA, bone resorption is increased and bone formation is normal or reduced in comparison to healthy controls. This uncoupling of bone formation and resorption with a negative remodelling balance lends to generalized bone loss. The pathogenesis of this altered bone metabolism is multifactorial, involving non-disease-specific factors (such as age, female sex and postmenopausal status) and disease-specific factors. Disease-specific factors are associated with disease activity (inflammatory cells and cytokines; hypogonadism), disease outcome (especially reduced mobility), and disease medication (e.g. corticosteroids).