Three-Dimensional Bone Structural Analysis in Postmenopausal Patients With Rheumatoid Arthritis With and Without Bone Erosion.

INTRODUCTION

This study compared the three-dimensional (3D) bone structure based on bone erosion in postmenopausal patients with rheumatoid arthritis (RA) using a novel dual-energy X-ray absorptiometry (DXA)-based 3D analysis tool.

METHODS

In this cross-sectional study, 171 postmenopausal women with RA (aged ≥ 50 years) were categorized based on bone erosions on hand and foot X-rays. We conducted 3D bone structure analyses on DXA hip scans using 3D-Shaper software, measuring volumetric BMD of integral (IvBMD), trabecular (TvBMD), and cortical (CvBMD) compartments.

RESULTS

The study included 94 patients without erosion and 77 with erosion. The erosion-positive group showed significantly lower femoral neck (FN) parameters: areal BMD (0.722 ± 0.090 vs. 0.756 ± 0.102 g/cm², p = 0.023), IvBMD (269.784 ± 49.306 vs. 288.610 ± 59.220 mg/cm³, p = 0.027), TvBMD (157.043 ± 39.154 vs. 170.787 ± 45.168 mg/cm³, p = 0.037), and CvBMD (709.563 ± 68.028 vs. 735.182 ± 81.470 mg/cm³, p = 0.026). Multiple regression analysis revealed that disease activity score (DAS28) was independently associated with FN CvBMD (β = -24.693, p = 0.023).

CONCLUSIONS

This study demonstrated that bone erosion in RA is associated with significant alterations in bone structure, particularly in the FN region. Disease activity primarily affects cortical bone, highlighting the need for stringent disease management to maintain bone health in patients with RA.