The Effects of Rheumatoid Factor, Functional Status and Disease Activity on Bone Loss in Rheumatoid Arthritis
2 Karaelmas Üniversitesi Tıp Fakültesi İmmünoloji Anabilim Dalı, Zonguldak
3 Hacettepe Üniversitesi Tıp Fakültesi Biyoistatistik Anabilim Dalı, Ankara
Objective: Generalized and periarticular osteoporosis are well-known phenomena in rheumatoid arthritis (RA). The pathogenesis of this bone mass loss in RA patients is not fully understood and considered as multifactorial. This study was designed to investigate the factors that effect bone loss in patients with RA.
Materials and Methods: Thirty patients with RA were included in this study. Bone mineral density (BMD) was measured using dual energy X-ray absorptiometry (DXA). Association between BMD and total and isotype of rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), Larsen’s score, Ritchie articular index (RAI) and Keitel functional index (KFI) were examined.
Results: Approximately 50% of patients had osteoporosis and osteopenia. While there was a negative correlation between RF and femur T score (r=-0.363, p= 0.049), T scores at the other measured sites were not significantly related to RF. We detected negative correlation between lumbar spine and ultradistal radius T score and disease duration (r=-0.393; p=0.032, r=-0.382; p=0.045 respectively). Correlation analyses revealed that forearm total and 1/3 distal radius t scores were negative correlated with KFI (r=-0.398; p=0.036, r=-0.412; p=0.029 respectively).
Conclusion: Higher titers of RF in RA patients may be accepted as a risk factor for progression of osteoporosis. Although bone loss starts in the early stage of the disease, it becomes worse with the duration and functional impairment of RA.
Keywords : Rheumatoid arthritis, bone mineral density, rheumatoid factor,Kietel Functional Index