Bone Mineral Density and Trabecular Bone Score Indices in Women with Rheumatoid Arthritis according to the Age and use of Glucocorticoids

Abstract

Objectives: The present study was aimed to establish the influence of age and use of glucocorticoids on the Bone Mineral Density (BMD), Trabecular Bone Score (TBS) indices and their dynamics during one year in women with RA. Material and Methods: We included 134 women with RA aged 31 to 78 years (mean age – 52.4 years; height – 1.64 m; weight – 68.5 kg; duration of RA – 9.1 years). While studying the effect of age on BMD and TBS indices the patients were divided into fve groups by decades and compared indices with reference data for Ukrainian population. In order to evaluate the effect of GC on the studied parameters women were divided into three groups: 1st group comprised of 37 patients who did not take GC, 2nd group – 47 patients who have been prescribed with GC only at exacerbation, of the short, less than 6 months term, 3rd group – 50 patients who continuously received GC at a dose of ≥5 mg by prednisone for over 3 years. We used dual energy X-ray absorptiometry (Prodigy, GE Lunar, Madison, 2005, USA), measured BMD at the lumbar spine, femoral neck and ultradistal radius. Trabecular bone tissue score (TBS) of the lumbar spine was determined by TBS iNsight® (Med-Imaps, Pessac, France). Results: Starting from the age of 50 years, the indices of TBS L1-L4 (1.156±0.140 vs. 1.318±0.155 in women aged 30–39 years; t=3.5; p=0.001) and BMD of different parts of the skeleton in women with RA are signifcantly decreasing. BMD indices of femoral neck and ultra distal radius in patients with RA aged 40-49, 50-59, 60-69 and 70-79 are lower than according parameters in healthy women. In addition, it was revealed that at the continuous administration of GC (in the 3rd group compared to the 1st group), TBS L1-L4 (1.147±0.168 Vs1.250±0.135; t=3.07; p=0.003) was signifcantly lower, while signifcant changes in BMD parameters of the lumbar spine and femur have not been detected. Over the year of follow-up, the index TBS L1-L4 in 1st group decreased by 1.4%, in 3rd group – by 5.8%. Thus, the defnition of TBS L1-L4 is a technique that can assess the impact of GC on bone tissue and dynamics of its loss as a result of treatment. Conclusion: The indices of TBS and BMD in women with RA aged 50 years and older are signifcantly lower than parameters in healthy women. Patients who receive GC continuously have signifcantly lower TBS L1-L4, in contrast of no signifcant changes in BMD. Consequently, the assessment of TBS L1-L4 is a technique that can assess the impact of GC on bone tissue and dynamics of its loss as a result of treatment.