Researchers Highlight Importance of Assessing Osteoporosis Risk Factors in RA

Researchers of a new study have compiled an array of considerations in assessing the risk of falls among patients with rheumatoid arthritis (RA), a disease that puts patients at a higher risk for weakened bones and fractures.

Risk of osteoporosis and bone fractures in RA stem from disease-specific causes, disease treatment, and factors that face the general population, according to the study, which highlighted the importance of assessing risk factors in these patients.

“Unfortunately, osteoporosis in the RA patient population is underdiagnosed and undertreated. Although RA is included in fracture risk calculators (such as the FRAX), the binary representation of RA in such algorithms does not adequately capture the complexity of the disease (severity, duration, and treatments). The increased risk of osteoporosis in RA has been attributed to inflammation, medications (notably glucocorticoids), as well as decreased physical activity and altered body composition. In addition to these disease-specific risk factors, traditional risk factors for osteoporosis also need to be considered in people with RA.”

Risk factors for low bone mineral density (BMD) in RA outlined by the group included autoantibodies—present in approximately half of patients with the disease—that are believed to contribute to RA pathogenesis and associated with more severe disease. For example, anti-citrullinated protein antibodies (ACPAs) have been shown to bind to and stimulate osteoclasts and have been linked with local joint erosions and systemic bone loss in RA.

Elevated inflammation—common in people with active disease—contribute to osteoporosis and may also contribute to loss of muscle mass and muscle function, lowering BMD and ultimately increasing the risk of frailty and falls.

BMD may also be impacted by glucocorticoids (GCs), which have been found to increase the risk of low BMD and poor bone quality and subsequently falls and fractures.

“Yet GCs remain a common medication in the treatment of RA, decreasing inflammation, joint pain and stiffness which can counteract the deleterious effects of GCs on BMD. It is unclear what the optimal dose of GCs are in the balance of treating RA disease and minimizing harm on bone density and quality,” described the researchers. “Because GC excess, even at low doses, can be harmful to skeletal health and many non-GC treatment options for RA exist, it is conditionally recommended by the 2020 American College of Rheumatology (ACR) RA guideline to follow a ‘treat-to- target’ strategy that avoids GCs.”

In addition to GCs, selective serotonin reuptake inhibitors and opiates have been associated with an increase in the risk of fractures in patients. Patients with RA who take both GCs and a proton pump inhibitor have been found to have an increased risk of osteoporotic fractures compared with patients using neither or either one of the medications. The use of several medications also exacerbates the risk, explained the researchers, noting that data has shown a 14% increase in risk of falls with each medication added to a 4-medication regimen among older patients.

The risk for falls and fractures has been associated with several patient characteristics, including age and body composition. The researchers flagged the risk of lower BMD associated with sarcopenia, which is independently associated with an increased risk of falls.

Reference

Baker R, Narla R, Baker J, Wysham K. Risk factors for osteoporosis and fractures in rheumatoid arthritis. Best Pract Res Clin Rheumatol. Published online October 5, 2022. doi:10.1016/j.berh.2022.101773