Micro-structural bone changes in early rheumatoid arthritis persist over 1-year despite use of disease modifying anti-rheumatic drug therapy

• Main Authors: Lynne M. Feehan, Linda L. Li, Heather A. McKay
• Format: Article
• Language: English
• Published: BMC 2017-12-01
• Series: BMC Musculoskeletal Disorders
• Subjects: High resolution – Peripheral quantitative computed tomography (HR-pQCT); Early rheumatoid arthritis; Disease modifying Antirheumatic drugs; Bone health; Osteoporosis; Fracture risk
• Online Access: http://link.springer.com/article/10.1186/s12891-017-1888-3

Abstract Background We used High Resolution – peripheral Quantitative CT (HR-pQCT) imaging to examine peri-articular bone quality in early rheumatoid arthritis (RA) and explore whether bone quality improved over 12-months in individuals receiving care consistent with practice guidelines. Methods A 1-year longitudinal cohort study (Baseline and 12-months) evaluating individuals with early RA compared to age/sex-matched peers. Personal demographic and health and lifestyle information were collected for all. Whereas, active joint count (AJC28), functional limitation, and RA medications were also collected for RA participants. HR-pQCT imaging analyses quantified bone density and microstructure in the Metacarpal Head (MH) and Ultra-Ultra-Distal (UUD) radius at baseline and 12-months. Analyses included a General Linear Modelling repeated measures analyses examined main effects for disease, time, and interaction on bone quality. Results Participants (n = 60, 30 RA/30 NRA); 80% female, mean age 53 (varying from 21 to 74 years). At baseline, RA participants were on average 7.7 months since diagnosis, presenting with few active joints (AJC28: 30% none, remaining 70% Median 4 active joints) and minimal self-reported functional limitation (mHAQ-DI0–3: 0.56). At baseline, 29 of 30 RA participants had received one or more non-biologic disease-modifying anti-rheumatic drugs (DMARD);13 in combination with glucocorticoid and 1 in combination with a biologic medication. One participant only received glucocorticoid medication. Four RA participants withdrew leaving 26 pairs (n = 52) at 12-months; 23 pairs (n = 46) with UUD and 22 pairs (n = 44) with MH baseline and 12-month images to compare. Notable RA/NRA differences (p < 0.05) in bone quality at all three sites included lower trabecular bone density and volume, more rod-like trabeculae, and larger and more variable spaces between trabeculae; fewer trabeculae at the UUD and MH2 sites; and lower cortical bone density and volume in the MH sites. Rate of change over 12-months did not differ between RA/NRA participants which meant there was also no improvement over the year in RA bone quality. Conclusions Early changes in peri-articular bone density and microstructure seen in RA are consistent with changes more commonly seen in aging bone and are slow or resistant to recover despite well controlled inflammatory joint symptoms with early DMARD therapy.