AB0235 DENOSUMAB INCREASE THE BONE MINERAL DENSITY REGARDLESS OF DISEASE ACTIVITY, THE BIOLOGICAL DISEASE-MODIFYING ANTIRHEUMATIC DRUGS, THE CONCOMITANT TYPE OF VITAMIN D, AND PRETREATMENT OF OSTEOPOROSIS IN PATIENTS WITH RHEUMATOID ARTHRITIS.

Abstract

Background:Osteoporosis is one of the major comorbidities in patients with rheumatoid arthritis (RA). There are a lot of evidence that denosumab increase bone mineral density (BMD) in patients with osteoporosis. However, there are few reports investigated the influence of denosumab in patients with RA.Objectives:We evaluated the BMD change in patients with RA treated denosumab and assessed the effect of various factors, such as disease activity, biological disease-modifying anti-rheumatic drugs (bDMARDs) use, concomitant medications of osteoporosis and pretreatment of osteoporosis.Methods:This study included 140 consecutive RA patients (135 female, mean age was 70.6 ± 8.6 years) who fullfilled the criteria of osteoporosis and treated with denosumab. BMD at the lumbar spine, proximal femoral and femoral neck were evaluated by dual energy X-ray absorptiometry at baseline and one year after treatment. We evaluated the influence of disease activity, bDMARDs use, the concomitant type of vitamin D and pretreatment of osteoporosis for BMD change.Results:BMD change at the lumbar spine, proximal femoral and femoral neck were 5.9% (p<0.01), 4.0% (p<0.01), and 1.2% (p=0.36) durling one year. There were no differences in improvement ratio of BMD between each parameters (fig 1). Disease activity: 75 patients in remission or low disease activity and 65 patients in moderate or high disease activity were 6.4 vs 5.3% (p=0.91), 3.0 vs 5.1% (p=0.73), 2.0 vs 0.3% (p=0.1). bDMARDs: 45 patients with bDMARDs (anti-tumor necrosis factor inhibitors (TNF): 23, tocilizmab (TCZ): 13, abatacept (ABT): 7, Tofacitinib: 2) and 93 patients without bDMARDs were 6.0 vs 5.8% (p=0.31), 4.3 vs 4.1% (p=0.57), -0.2 vs 1.8% (p=0.18). Type of vitamin D: 47 patients taking active form vitamin D and 60 patients taking native form vitamin D were 5.5 vs 6.8% (p=0.82), 3.1 vs 3.8% (p=0.93), 0.4 vs 1.9% (p=0.14). Pretreatment of osteoporosis: 74 patients with pretreatment of osteoporosis (bisphosphonate:58, teriparatide:16) and 66 patients without pretreatment of osteoporosis were 6.9 vs 5.4% (p=0.41), 0.9 vs 4.0% (p=0.22), 2.0 vs 1.2% (p=0.68). Moreover, BMD change were not different in bDMARDs type, 5.0, 6.4, 0.5% in TNF group, 4.8, 0.7, -1.9% in TCZ group, 9.7, 4.9, 0.2% in ABT group (TNF vs TCZ: p=0.83, 0.98, 0.81, TNF vs ABT: p=0.83, 0.41, 0.97, TCZ vs ABT: p=0.98, 0.43, 0.9). There were no difference between bisphosphonate and teriparatide (6.2 vs 6.9%: p=0.49, 4.8 vs 0.9%: p=0.35, 0.9 vs 2.0%: p=0.49).Conclusion:Denosumab improved BMD in patients with RA independently regardless of disease activity, bDMARDs, the concomitant type of vitamin D and pretreatment of osteoporosis.