Osteoporosis: an Independent Determinant of Bone Erosions in Rheumatoid Arthritis?

Changes in bone turnover markers and bone modulators during abatacept treatment

Rheumatoid arthritis (RA) causes bone loss, only partly related to inflammation. The impact of RA treatments on bone metabolism and their ability to mitigate bone loss remains uncertain. The primary goal of our study was to examine the influence of abatacept on serum levels of markers and regulators involved in bone turnover. Secondary objectives included evaluating changes in bone mineral density (BMD), bone health parameters, erosions, and exploring potential correlations among these parameters. We conducted a prospective observational study on patients with active seropositive RA failure to biological disease modifying anti-rheumatic drugs initiating treatment with abatacept. We measured at baseline and after 1, 2, 3, 6, 9 and 12 months: serum bone turnover markers (CTX, P1nP, B-ALP), bone modulators (Dkk-1, sclerostin, vitamin D, PTH, OPG and RANKL), BMD and radiographic parameters (modified Sharp van der Heijde score [mSvdH], bone health index [BHI] and metacarpal index [MCI]). Disease activity and glucocorticoid intake was monitored. 33 patients were enrolled in the study. We found a significant increase in markers of bone formation (B-ALP and P1nP) from baseline to M6 and M12. PTH increased significantly at M6 but not at M12. All other bone markers and modulators did not change. We found a significant decrease in BHI and MCI from baseline to M12 (median difference - 0.17 95% CI - 0.42 to - 0.10, p 0.001 and - 0.09 95% CI - 0.23 to - 0.07, respectively). BMD at femoral neck transitorily decreased at M6 (mean difference - 0.019 g/cm2 95% CI - 0.036 to - 0.001 p 0.04). BMD at total hip, lumbar spine and mSvdH score did not change significantly. P1nP delta at M12 correlated with delta mSvdH. Treatment with abatacept was associated with a significant increase in bone formation markers. The secondary and transient increase in PTH serum levels may be responsible of the transitory bone loss.

Radiological Evaluation of Cervical Spine Involvement in Rheumatoid Arthritis: A Cross-Sectional Retrospective Study

Background: Cervical spine lesions are a common manifestation of rheumatoid arthritis (RA). The purpose of this study was to conduct a retrospective analysis of radiological lesions in cervical spine in patients with RA and to correlate findings with clinical and laboratory parameters. Methods: Overall, 240 consecutive patients with RA were referred for imaging by clinicians based on symptoms suggesting cervical spine involvement and/or long disease duration. In each patient, lateral radiographs and MRI of the cervical spine were performed. The imaging data were correlated with clinical records and laboratory data. Results: The cervical spine was affected in 179 patients (75%). The most common lesions were anterior atlanto-axial subluxation (AAS; 58%), subaxial subluxation (58%), and demineralization (48%). Cervical spine involvement was linked to longer disease duration (p = 0.007), the presence of rheumatoid factor (RF; p = 0.010), elevated C-reactive protein (CRP) levels (p = 0.016), and accelerated erythrocyte sedimentation rate (ESR; p = 0.025). Longer disease duration was associated with anterior AAS (p = 0.005), subaxial subluxation (p = 0.005), and basilar settling (p = 0.003). Conclusions: As many as 75% of RA patients develop lesions that can be observed on radiographs and through MRI. The most frequent radiological findings include anterior AAS and subaxial subluxation. Long disease duration, RF seropositivity, and elevated inflammatory markers were risk factors for cervical spine involvement.

The Emerging Roles of Endocrine Hormones in Different Arthritic Disorders

The relationship between endocrine hormones and the spectrum of rheumatic conditions has long been discussed in the literature, focusing primarily on sexual hormones, such as estrogens, androgens, prolactin (PRL). Estrogens are indeed involved in the pathogenesis of the main inflammatory arthritis thanks to their effects on the immune system, both stimulatory and inhibitory. The PRL system has been discovered in synovial tissue of rheumatoid arthritis (RA) and psoriatic arthritis (PsA), patients and has been propose as a new potential therapeutic target. Besides sexual hormones, in the last years scientific interest about the crosstalk of immune system with other class of hormones has grown. Hormones acting on the bone tissue (i.e. parathyroid hormone, vitamin D) and modulators of the Wnt pathway (i.e. Dickkopf-1) have been demonstrated to play active role in inflammatory arthritis course, defining a new field of research named osteoimmunology. PTH, which is one of the main determinants of Dkkopf-1, plays a crucial role in bone erosions in RA and a correlation between PTH, Trabecular Bone Score (TBS) and disease activity has been found in ankylosing spondylitis (AS). In PSA is under studying the interaction among IL-17 and bone metabolism. The purpose of this review is to discuss and summarize the recent data about the interaction between endocrine hormone and immune system in the main rheumatic disorders, covering in particular the role of bone-related hormones and cytokines. We will describe this relationship from a biochemical, diagnostic and therapeutic perspective, with a particular focus on RA, PsA and AS.

Osteoporosis in Inflammatory Arthritides: New Perspective on Pathogenesis and Treatment

Osteoporosis is a skeletal disorder characterized by impaired bone strength and increased risk of fragility fracture and is among the most relevant comorbidities of rheumatic diseases. The purpose of the present review is to discuss the pathogenesis of local and systemic bone involvement in inflammatory arthritides, especially Rheumatoid Arthritis, Psoriatic Arthritis, and Spondyloarthritides, as well as the effect of anti-rheumatic treatments and anti-osteoporotic medication on bone health and fracture incidence, including recent data on novel therapeutic perspective.

Osteoimmunology in rheumatoid and psoriatic arthritis: potential effects of tofacitinib on bone involvement

Chronic inflammation, such as that present in rheumatoid arthritis (RA) and psoriatic arthritis (PsA), leads to aberrations in bone remodeling, which is mediated by several signaling pathways, including the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway. In this light, pro-inflammatory cytokines are now clearly implicated in these processes as they can perturb normal bone remodeling through their action on osteoclasts and osteoblasts at both intra- and extra-articular skeletal sites. As a selective inhibitor of JAK1 and JAK3, tofacitinib has the potential to play a role in the management of rheumatic diseases such as RA and PsA. Preclinical studies have demonstrated that tofacitinib can inhibit disturbed osteoclastogenesis in RA, which suggests that targeting the JAK-STAT pathway may help limit bone erosion. Evidence from clinical trials with tofacitinib in RA and PsA is encouraging, as tofacitinib treatment has been shown to decrease articular bone erosion. In this review, the authors summarize current knowledge on the relationship between the immune system and the skeleton before examining the involvement of JAK-STAT signaling in bone homeostasis as well as the available preclinical and clinical evidence on the benefits of tofacitinib on prevention of bone involvement in RA and PsA.Key Points• Chronic inflammation in rheumatoid arthritis (RA) and psoriatic arthritis (PsA) leads to disturbances in bone remodeling• Bone remodeling is mediated by several signaling pathways, including the JAK-STAT pathway• Tofacitinib, a selective inhibitor of JAK1 and JAK3, is active in RA and PsA and may help limit systemic bone loss through inhibiting disturbed osteoclastogenesis• Clinical trials show that tofacitinib reduces articular bone erosion.

Osteoporosis in Rheumatic Diseases

Osteoporosis is a chronic disease characterized by an increased risk of fragility fracture. Patients affected by rheumatic diseases are at greater risk of developing osteoporosis. The purpose of the present review is to discuss the pathogenesis, epidemiology, and treatment of osteoporosis in patients affected by rheumatic diseases with special focus for rheumatoid arthritis, psoriatic arthritis, spondyloarthritis, systemic lupus erythematosus, systemic sclerosis, vasculitides, Sjogren syndrome, and crystal-induced arthritis.

Inhibition of tumor necrosis factor-alpha (TNF-alpha) in patients with early rheumatoid arthritis results in acute changes of bone modulators

OBJECTIVE

Dicckopf-1 (Dkk-1) is a potent inhibitor of the Wnt canonical pathway. In rheumatoid arthritis (RA), Dkk-1 is upregulated by tumor necrosis factor-α (TNF). Certolizumab pegol (CMZ) is a biologic TNF-inhibitor (TNFi) effective in RA and slows radiographic progression. Data on the immediate effects (≤1-8 weeks) of TNFi on Wnt modulators are lacking. This study investigated the acute influence of TNFi treatment on Wnt modulators (Dkk-1 and sclerostin) and bone turnover markers (BTM), including intact N-terminal propeptide of collagen type I (PINP) and C-terminal telopeptide of type I collagen (CTX-I).

METHODS

This longitudinal, uncontrolled study involved female RA patients with inadequate response to conventional methotrexate who underwent treatment with CMZ. ESR, Dkk-1, sclerostin, BTM, parathyroid hormone (PTH), and 25OH-vitamin D levels were evaluated at baseline, week 1, week 4, and week 8. Radiographs of the hands and feet were obtained at baseline and the total and erosion scores were assessed using the Simple Erosion Narrowing Score method (SENS).

RESULTS

Seventeen patients were enrolled. Dkk-1 and CTX-I significantly decreased after one week of treatment with CMZ (-49.1 ± 17.1% and -25.0 ± 20.6%, respectively, p < 0.01), whereas PINP increased (+43.2 ± 31.5%, p < 0.01). These changes persisted at week 4 and 8.

CONCLUSIONS

Our study showed that TNF-alpha inhibition with CMZ promptly results in a rapid decline of serum Dkk-1 levels, alongside decreased bone resorption and increased bone formation.

Impact of switching oral bisphosphonates to denosumab or daily teriparatide on the progression of radiographic joint destruction in patients with biologic-naïve rheumatoid arthritis

In biologic-naïve female RA patients, switching oral BPs to DMAb significantly reduced radiographic joint destruction compared to continuing oral BPs or switching to TPTD at 12 months, which were significantly associated with a decrease of a bone resorption marker at 6 months.

INTRODUCTION

The aim of this study was to clarify the effects of switching oral bisphosphonates (BPs) to denosumab (DMAb) or daily teriparatide (TPTD) on the progression of radiographic joint destruction in patients with biologic-naïve rheumatoid arthritis (RA).

METHODS

A retrospective, case-controlled study involving 90 female RA patients (mean age 68.2 years, 96.7% postmenopausal, disease activity score assessing 28 joints with CRP (DAS28-CRP) 2.4, methotrexate treatment 81.1%, prednisolone treatment 68.9%, and prior BP treatment 44.8 months), who were allocated depending on each patient's and physician's wishes, to (1) the BP-continue group (n = 30), (2) the switch-to-DMAb group (n = 30), or (3) the switch-to-TPTD group (n = 30), was conducted. Patients were retrospectively selected to minimize the difference of possible clinical backgrounds that may affect the joint destruction of RA. The primary endpoint was to clarify the change of the modified total Sharp score (mTSS) from baseline to 12 months.

RESULTS

After 12 months, the mean changes of the modified Sharp erosion score were significantly lower in the switch-to-DMAb group (0.2 ± 0.1; mean ± standard error) than in the switch-to-TPTD group (1.3 ± 0.5; P < 0.05), and mTSS was significantly lower in the switch-to-DMAb group (0.3 ± 0.2) than in the BP-continue group (1.0 ± 0.3; P < 0.05) and the switch-to-TPTD group (1.7 ± 0.6; P < 0.05). The logistic regression analysis showed that mTSS changes were significantly associated with the percent changes of TRACP-5b at 6 months (β = 0.30, 95% CI = 0.002-0.016; P < 0.01).

CONCLUSIONS

Changes of systemic bone turnover induced by switching BPs to DMAb or TPTD may affect not only systemic bone mass, but also local joint destruction, and its clinical relevance should be considered comprehensively.