AB0898 IMPACT OF BIOLOGICAL AGENTS, ORAL GLUCOCORTICOIDS, OR BOTH ON THE EFFICACY OF DAILY TERIPARATIDE TREATMENT FOR OSTEOPOROSIS IN PATIENTS WITH RHEUMATOID ARTHRITIS

Abstract

Background:Daily teriparatide (dTP) strongly affects bone metabolism in patients with rheumatoid arthritis (RA), resulting in increased bone mineral density (BMD). We reported the 2-year results of dTP treatment for osteoporosis (OP) in patients with RA in EULAR2014 [1]. Drugs affecting bone metabolism, such as biological agents (BIOs) and glucocorticoids (GCs), are frequently administered to patients with RA in addition to dTP in daily clinical practice. Although dTP increases bone turnover, BIOs reduce osteoclast activity and GCs decrease bone turnover. We reported the effects of GCs or BIOs on the efficacy of dTP in EULAR2015 [2]. The present retrospective study investigated the effects of GCs or BIOs on the efficacy of dTP in patients with RA using a larger patient cohort.Objectives:To evaluate the effects of BIOs, GCs, or both on the efficacy of dTP treatment for OP in patients with RA.Methods:The study included 56 female patients who had completed 2 years of dTP treatment. We separated these patients into four groups according to their treatment regimen at dTP initiation: B(−)G(−),included patients who did not receive BIOs or GCs (n = 14); B(+)G(−), included patients treated only with BIOs (n = 8); B(−)G(+), included patients treated only with GCs (n = 24); and B(+)G(+),included patients treated with both BIOs and GCs (n = 10). We determined baseline (BL) characteristics, % changes in BMD in the lumbar spine (LS) and total hip (TH) from BL to 24 months, and % changes in serum bone turnover markers (BTMs), such as BAP, P1NP, NTX, and TRACP-5b, from BL to 6 months after dTP initiation. Dunnett’s test was used for comparisons between B(−)G(−) and other groups.Results:The mean ages of the B(−)G(−), B(+)G(−), B(−)G(+), and B(+)G(+) groups at BL were 70.0, 65.5, 69.6, and 71.5 years, whereas the mean duration of RA in these groups were 15.4, 20.8, 69.9, and 71.5 years, respectively. Furthermore, the mean baseline DAS28-CRP levels in these groups were 2.8, 2.2, 2.8, and 2.3. The mean LS-BMD (g/cm2) at BL were 0.795, 0.819, 0.826, and 0.853, whereas the mean TH-BMD at BL were 0.619, 0.570, 0.601, and 0.629, respectively. The mean % changes in LS-BMD at 24 months were 15.5%, 12.7%, 11.9%, and 8.1%, respectively (Fig 1A). There were no significant differences between B(−)G(−) and other groups. The mean % changes in TH-BMD at 24 months in the B(−)G(−), B(+)G(−), B(−)G(+), and B(+)G(+) groups were 6.4%, 5.3%, 4.4%, and 1.5%, respectively (Fig 1B) A significant difference was observed between the B(−)G(−) and B(+)G(+) groups (p = 0.03). The % changes in BTMs in the B(−)G(−), B(+)G(−), B(−)G(+), and B(+)G(+) groups were as follows: BAP, 90.5%, 44.0%, 29.5%, and 87.7%; P1NP, 374.1%, 338.2%, 225.9%, and 640.0%; NTX, 75.2%, 106.6%, 42.5%, and 80.5%; and TRACP-5b, 75.8%, 43.85, 20.4%, and 122.3%, respectively. No significant differences were observed in the changes in BTMs among the groups.Conclusion:This study suggested that concomitant use of BIOs and GCs inhibited the increase in BMD induced by dTP treatment in patients with RA, particularly TH-BMD. Although BTM analysis revealed no statistical significance, GCs tended to decrease the % change in BTMs.