A decrease in bone mineral density (BMD) has been shown to predict radiographic joint progression in early rheumatoid arthritis, but a new study suggests BMD loss just 3 months after diagnosis can independently predict radiologic damage at 1 year.
For patients with a diagnosis of rheumatoid arthritis, early treatment with disease-modifying antirheumatic drugs (DMARDs) is known to improve disease outcomes. However, improved prediction of the individual disease course could help doctors optimize antirheumatic therapy.
Digital X-ray radiogrammetry (DXR) uses computerized analyses of standard hand radiographs to estimate peripheral BMD of the 3 middle metacarpal bones (DXR-BMD). Although DXR-BMD loss has repeatedly been shown to predict radiographic joint progression in early rheumatoid arthritis, the majority of previous studies have been based on a 12-month change.
Led by Michael Ziegelasch of Linköping University in Sweden, researchers writing in Arthritis Research & Therapy found that DXR-BMD loss during the initial 3 months after rheumatoid arthritis diagnosis independently predicted radiologic damage at 1 year. Because evaluation of prescribed DMARDs often is performed 3 months after initiation in clinical practice, additional information on the patient’s radiographic prognosis at this time would be highly valuable to optimize future therapy decisions.
This study consisted of 176 patients with early rheumatoid arthritis from 3 Swedish rheumatology centers. All patients fulfilled the 2010 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) or the 1987 ACR classification criteria for rheumatoid arthritis.
Pharmacotherapy was prescribed as found appropriate by the treating rheumatologist, according to Swedish guidelines, wherein 91% received conventional synthetic DMARDs (1 patient started on a tumor necrosis factor inhibitor at baseline). Patients were monitored for 2 years, and 14.4% received biologic therapy in the follow-up period.
Radiographs (posterior-anterior projection) of the hands, wrists, and forefeet were performed at baseline, 3 months (hands only), and 1 and 2 years. The radiographs were evaluated according to the Larsen score. Radiographic progression was defined as a difference in Larsen score above the smallest detectable change of the corresponding reader.
Ziegelasch M, Forslind K, Skogh T, et al. “Decrease in bone mineral density during three months after diagnosis of early rheumatoid arthritis measured by digital X-ray radiogrammetry predicts radiographic joint damage after one year.” Arthritis Res Ther. 2017 Sep 2;19(1):195. doi: 10.1186/s13075-017-1403-0.