Background: Glucocorticosteroids (GCS) are widely used in the treatment of rheumatoid arthritis (RA) as bridge-therapy. Though, according to last recommendations for the treatment of RA GCS should be considered in short-term and different dose regimens and routes of administration and should be tapered as rapidly as clinically feasible. But in some cases, patients received GCS for a long period in low doses (<7.5 mg/day prednisone equivalent). It is well known, that long-term GCS use is associated with osteoporosis and increased risk of fracture, even at low daily doses. On the other hand, RA itself leads to the changes in the biomechanical properties of bones through the increased production of pro-inflammatory cytokines. Furthermore, immobilization due to pain from inflamed joints and impairment of physical activity are in response for osteoporosis formation. In addition, patients with RA are often co-prescribed a proton pump inhibitor, which have a reported effect on occurrence of osteoporosis. Taking into consideration all mentioned above patients with RA, receiving GCS therapy reveal high risk for osteoporosis and fracture formation and require corresponding treatment.

Objectives: The aim of this study is to evaluate the effect of 12 months treatment with denosumab (bone-modifying agent) in patients with RA, continuing to receive GCS.

Methods: 50 female patients with RA (mean age 54 ± 6.3 years) were enrolled in this study. Duration of RA was 10.5 ± 3.2 years. All patients received prednisone 15,3± 10,25 mg/day with gradually escalation of dose for ≥ 12 months. As DMARD therapy patients received methotrexate dose in average 15-20mg/week (75%), leflunomide 20 mg/day (25%). Bone mineral density (BMD) is measured in all patients by Dual-energy X-ray absorptiometry (DEXA) at baseline and 12 months after treatment with denosumab. All patients received denosumab 60 mg subcutaneously once every 6 months.

Results: The measurement of BMD at baseline revealed the following results: T-score in lumbar spine was -1,95 ± 1,36 and in total hip -1,64± 0,94 with high major osteoporotic fracture risk. All patients completed the study. The BMD after 12 months significantly increased both in lumbar spine +4,2 % (p<0,001) and in total hip +2,1% (p<0,001).

Conclusion: Denosumab should be considered as a drug of choice in RA patients, continuing to receive GCS. Further large investigations are needed to assess the BMD after discontinuation of denosumab and evaluate fracture risk in this population of patient.

REFERENCES:

[1]J.Compston. Glucocorticoid-induced osteoporosis: an update. Endocrine. 2018; 61(1): 7–16. doi: 10.1007/s12020-018-1588-2

[2]A.Giovanni, S.Kenneth. Glucocorticoid-induced osteoporosis update. Current Opinion in Rheumatology: 2019;31(4): 388-393. doi: 10.1097/BOR.0000000000000608

Disclosure of Interests: None declared