The change of bone mineral density according to treatment agents in patients with ankylosing spondylitis

Effect of bisphosphonates on ankylosing spondylitis: A meta-analysis

This study aimed to compare outcomes between ankylosing spondylitis (AS) treated with and without bisphosphonate (BP; non-BP) through a meta-analysis. The Medline (via PubMed), Cochrane, Scopus, and Embase databases were searched for studies that evaluated the outcomes of AS, including patient age, disease duration, disease activity, and bone mineral density (BMD), published between January 2000 and March 2020. Two authors extracted the data independently. Any discrepancies were resolved by a consensus. Six comparative studies were identified. No significant differences were found between the BP and non-BP groups in terms of demographic characteristics, disease activity, and BMD, except for follow-up erythrocyte sedimentation rate (ESR). The follow-up ESR was higher in the BP than in the non-BP group. A literature review identified six comparative studies reporting the outcomes of BP and non-BP treatments for AS. Despite the heterogeneity, a limited number of meta-analyses reported that BP treatment was not clearly better than non-BP treatment. Hence, further large-scale multicenter studies are required to validate our results.

Effects of Long-Term Methotrexate, Infliximab, and Tocilizumab Administration on Bone Microarchitecture and Tendon Morphology in Healthy Wistar Rats

Objective

Rheumatic diseases are associated with bone loss, both systemic and periarticular, and tendon abnormalities. The aim of this study is to examine the effect of three antiarthritic drugs, methotrexate, an anti-folate metabolite; infliximab, a Tumor Necrosis Factor-alpha (TNF-α) inhibitor; and tocilizumab, an antibody against Interleukin-6 (IL-6) receptor, on bone microarchitecture and tendon morphology in the absence of an inflammatory state.

Materials and methods

Thirty-five, 8- to 9-week-old, male, Wistar rats were randomly allocated into five groups: negative control (CTRL), vehicle (VEH), methotrexate (MTX), infliximab (INFX), and tocilizumab (TCZ). After 8 weeks of antiarthritic drug intraperitoneal administration, animals were euthanized and rat tibiae and patellar tendons were histologically examined.

Results

All sections exhibited normal bone microarchitecture. Histological scores in all groups corresponded to normal bone mineral density. No no apparent differences in tenocyte morphology and architecture of collagen fibers were observed.

Conclusions

The results of this study indicate that long-term administration of methotrexate, infliximab, and tocilizumab had no effect on bone microarchitecture and tendon morphology in rats in the absence of an inflammatory condition.

A 2-year longitudinal study of bone health in adolescent patients with axial spondyloarthritis

PURPOSE

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease that primarily affects the axial skeleton and typically has an early onset. Although earlier onset is associated with worse prognosis, there have been few studies of bone mineral density (BMD) in adolescent patients with axSpA.

METHODS

We analysed the clinical characteristics of 43 adolescent patients with axSpA at a baseline assessment and at a follow-up 2 years later. The baseline assessment included age, disease duration, treatment agents, and clinical, radiologic, and laboratory data. BMD of the lumbar spine, femoral neck, and total hip were measured by dual-energy X-ray absorptiometry during both the baseline assessment and the 2-year follow-up. We performed multivariate linear regression analyses to identify factors independently associated with BMD. We analysed the associations between changes in BMD and reductions in inflammatory markers.

RESULTS

The average age of participants was 17.9 years and the mean disease duration was 2.2 years. Of the 43 patients, 10 (23%) had low BMD at any site (lumbar spine, femoral neck, and/or total hip). At baseline, multivariate analysis showed that body mass index (BMI), erythrocyte sedimentation rate (ESR), and spinal structural damage were associated with lumbar spine Z-scores. Increases in BMD in the lumbar spine were correlated with reductions in ESR (r = 0.40, P = 0.02) and C-reactive protein (CRP) (r = 0.40, P = 0.02). Increases in BMD in the total hip were correlated with reductions in CRP (r = 0.38, P = 0.03).

CONCLUSION

In adolescent axSpA patients, bone health was associated with systemic inflammation and the severity of structural damage. Reduced systemic inflammation was associated with improvements in bone health.

Bone mineral density improves during 2 years of treatment with bisphosphonates in patients with ankylosing spondylitis

Aims

To evaluate whether 2 years of treatment with bisphosphonates in combination with calcium/vitamin D supplements has an effect on lumbar spine and hip bone mineral density (BMD) in ankylosing spondylitis (AS) patients starting tumour necrosis factor‐α inhibitors or receiving conventional treatment. Secondly, to explore the development of radiographic vertebral fractures.

Methods

Patients from the Groningen Leeuwarden AS cohort receiving bisphosphonates based on clinical indication and available 2‐year follow‐up BMD measurements were included. BMD of lumbar spine (L1–L4) and hip (total proximal femur) were measured using dual‐energy X‐ray absorptiometry. Spinal radiographs (Th4–L4) were scored for vertebral fractures according to the Genant method.

Results

In the 20 included patients (median 52 years, 14 males), lumbar spine and hip BMD Z‐scores increased significantly; median from −1.5 (interquartile range [IQR] −2.2 to 0.4) to 0.1 (IQR −1.5 to 1.0); P < .001 and median from −1.0 (IQR −1.6 to −0.7) to −0.8 (IQR −1.2 to 0.0); P = .006 over 2 years, respectively. In patients also treated with tumour necrosis factor‐α inhibitors (n = 11), lumbar spine and hip BMD increased significantly (median 2‐year change +8.6% [IQR 2.4 to 19.6; P = .009] and +3.6% [IQR 0.7–9.0; P = .007]). In patients on conventional treatment (n = 9), lumbar spine BMD increased significantly (median 2‐year change +3.6%; IQR 0.7 to 9.0; P = .011) and no improvement was seen in hip BMD (median −0.6%; IQR −3.1 to 5.1; P = .61). Overall, younger AS males with limited spinal radiographic damage showed most improvement in lumbar spine BMD. Four mild radiographic vertebral fractures developed in 3 patients and 1 fracture increased from mild to moderate over 2 years in postmenopausal women and middle‐aged men.

Conclusion

This explorative observational cohort study in AS showed that 2 years of treatment with bisphosphonates in combination with calcium/vitamin D supplements significantly improves lumbar spine BMD. Mild radiographic vertebral fractures still occurred.

Low bone mineral density of vertebral lateral projections can predict spinal radiographic damage in patients with ankylosing spondylitis

OBJECTIVES

To investigate the association between bone mineral status and spinal radiographic damage in patients with ankylosing spondylitis (AS) and determine whether bone mineral status can predict further spinal radiographic damage after 2 years.

METHODS

Bone mineral density (BMD) of the lumbar spine (anteroposterior and lateral projections), femoral neck, and total hip and trabecular bone score (TBS) of the lumbar spine were measured in AS patients (n = 54) who fulfilled the modified New York criteria. Spinal radiographic damage was scored on cervical and lumbar spine radiographs using modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) at baseline and after 2 years. Simple and multiple linear regression analyses were performed to examine predictors of spinal radiographic damage.

RESULTS

Patients with advanced AS exhibited low BMD on lumbar spine lateral projections, femoral neck, and total hip and low TBS. Low vertebral bone mass at baseline, assessed by BMD of the lateral projections or TBS, was independently associated with baseline mSASSS. After 2 years, mSASSS change from baseline was significantly associated with high baseline mSASSS, high baseline erythrocyte sedimentation rate and C-reactive protein (CRP) levels, and low baseline BMD of the lumbar spine lateral projections. The best predictive model for spinal radiographic progression consisted of baseline mSASSS, baseline CRP, and low BMD of lateral lumbar spine (area under curve = 0.826).

CONCLUSIONS

BMD at vertebral lateral projections and TBS were inversely associated with baseline mSASSS in AS patients. Low BMD at vertebral lateral projections, as well as baseline mSASSS and inflammatory markers, might predict spinal radiographic damage in AS.Key Points• Vertebral bone mineral density of lateral projections and trabecular bone score are inversely associated with baseline mSASSS in patients with ankylosing spondylitis.• Baseline mSASSS, inflammatory markers, and low vertebral bone mineral density might predict spinal radiographic progression in patients with ankylosing spondylitis.

Osteoporosis in Rheumatic Diseases: Anti-rheumatic Drugs and the Skeleton

Osteoporosis in rheumatic diseases is a very well-known complication. Systemic inflammation results in both generalized and localized bone loss and erosions. Recently, increased knowledge of inflammatory process in rheumatic diseases has resulted in the development of potent inhibitors of the cytokines, the biologic DMARDs. These treatments reduce systemic inflammation and have some effect on the generalized and localized bone loss. Progression of bone erosion was slowed by TNF, IL-6 and IL-1 inhibitors, a JAK inhibitor, a CTLA4 agonist, and rituximab. Effects on bone mineral density varied between the biological DMARDs. Medications that are approved for the treatment of osteoporosis have been evaluated to prevent bone loss in rheumatic disease patients, including denosumab, cathepsin K, bisphosphonates, anti-sclerostin antibodies and parathyroid hormone (hPTH 1-34), and have some efficacy in both the prevention of systemic bone loss and reducing localized bone erosions. This article reviews the effects of biologic DMARDs on bone mass and erosions in patients with rheumatic diseases and trials of anti-osteoporotic medications in animal models and patients with rheumatic diseases.

Which measuring site in ankylosing spondylitis is best to detect bone loss and what predicts the decline: results from a 5-year prospective study

BACKGROUND

Studies have shown increased prevalence of osteoporosis and increased risk for vertebral fractures in patients with ankylosing spondylitis (AS). Measurements of bone mineral density (BMD) in the lumbar spine anterior-posterior (AP) projection may be difficult to interpret due to the ligamentous calcifications, and the lateral projection might be a better measuring site. Our objectives were to investigate BMD changes after 5 years at different measuring sites in patients with AS and to evaluate disease-related variables and medications as predictors for BMD changes.

METHODS

In a longitudinal study, BMD in Swedish AS patients, 50 ± 13 years old, was measured with dual-energy x-ray absorptiometry (DXA) at the hip, the lumbar spine AP and lateral projections, and the total radius at baseline and after 5 years. Patients were assessed with questionnaires, blood samples, and spinal radiographs for grading of AS-related alterations in the spine with the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) and assessment of vertebral fractures by the Genant score. Multiple linear regression analyses were used to investigate predictors for BMD changes.

RESULTS

Of 204 patients included at baseline, 168 (82%) were re-examined after 5 years (92 men and 76 women). BMD decreased significantly at the femoral neck and radius and increased significantly at the lumbar spine, both for AP and lateral projections. Mean C-reactive protein during follow-up predicted a decrease in the femoral neck BMD (change in %, β = -0.15, p = 0.046). Use of bisphosphonates predicted an increase in BMD at all measuring sites (p < 0.001 to 0.013), except for the total radius. Use of tumor necrosis factor inhibitors (TNFi) predicted an increase in AP spinal BMD (β = 3.15, p = 0.012).

CONCLUSION

The current study (which has a long follow-up, many measuring sites, and is the first to longitudinally assess the lateral projection of the spine in AS patients) surprisingly showed that lateral projection spinal BMD increased. This study suggests that the best site to assess bone loss in AS patients is the femoral neck and that inflammation has an adverse effect, and the use of bisphosphonates and TNFi has a positive effect, on BMD in AS patients.

Decreased Serotonin Levels and Serotonin-Mediated Osteoblastic Inhibitory Signaling in Patients With Ankylosing Spondylitis

Evidence suggests that serotonin is an inhibitor of bone formation. We aimed to assess: 1) serum serotonin levels in patients with ankylosing spondylitis (AS), a prototype bone-forming disease, compared with patients with rheumatoid arthritis (RA) and healthy subjects; 2) the effect(s) of TNFα blockers on serum serotonin levels in patients with AS and RA; and 3) the effect(s) of serum of AS patients on serotonin signaling. Serum serotonin levels were measured in 47 patients with AS, 28 patients with RA, and 40 healthy subjects by radioimmunoassay; t test was used to assess differences between groups. The effect of serum on serotonin signaling was assessed using the human osteoblastic cell line Saos2, evaluating levels of phospho-CREB by Western immunoblots. Serotonin serum levels were significantly lower in patients with AS compared with healthy subjects (mean ± SEM ng/mL 122.9 ± 11.6 versus 177.4 ± 24.58, p = 0.038) and patients with RA (mean ± SEM ng/mL 244.8 ± 37.5, p = 0.0004). Patients with AS receiving TNFα blockers had significantly lower serotonin levels compared with patients with AS not on such treatment (mean ± SEM ng/mL 95.8 ± 14.9 versus 149.2 ± 16.0, p = 0.019). Serotonin serum levels were inversely correlated with pCREB induction in osteoblast-like Saos-2 cells. Serotonin levels are low in patients with AS and decrease even further during anti-TNFα treatment. Differences in serotonin levels are shown to have a functional impact on osteoblast-like Saos-2 cells. Therefore, serotonin may be involved in new bone formation in AS.

Etanercept Increases Bone Mineral Density in Ankylosing Spondylitis, but Does Not Prevent Vertebral Fractures: Results of a Prospective Observational Cohort Study

OBJECTIVE

Ankylosing spondylitis (AS) is characterized by chronic inflammation leading to ankylosis, but also to low bone mineral density (BMD) and vertebral fractures (VFx). Treatment with tumor necrosis factor-α blockers decreases inflammation and has shown to be effective in increasing BMD. We studied the effects of etanercept (ETN) on BMD and VFx in patients with AS after 2 years of treatment. Further, we studied changes in bone turnover markers and radiological damage.

METHODS

Patients with active AS, treated with ETN for 2 years, were included. BMD lumbar spine and hip were measured at baseline and after 2 years, as well as radiological damage (modified Stoke Ankylosing Spondylitis Spinal Score with the addition of the thoracic spine), VFx (Genant method), and change in bone turnover markers.

RESULTS

Forty-nine patients with AS were included. After 2 years of ETN, hip BMD increased by 2.2% (p = 0.014) and lumbar spine BMD by 7.0% (p < 0.001). The Bath Ankylosing Spondylitis Disease Activity Index decreased significantly (p < 0.001), as well as C-reactive protein and erythrocyte sedimentation rate (p < 0.001). Despite ETN therapy, the number of patients with VFx more than doubled (from 6 to 15 patients, p = 0.003). Also, the radiological damage increased significantly over time (from 12.1 to 18.5, p < 0.001); however, no significant change in bone turnover markers was found.

CONCLUSION

This prospective longitudinal observational cohort study showed that after 2 years of ETN, BMD of the hip and spine increased significantly, but the number of patients with VFx and the severity of VFx increased as well. Besides that, radiological progression, including the thoracic spine, increased significantly. Thus, the favorable bone-preserving effect is accompanied by unfavorable outcomes on VFx and radiological damage.

Factors associated with bone mineral density loss in patients with spondyloarthropathies: A 4-year follow-up study

OBJECTIVE

To explore the relationship between laboratory, functional, disease activity markers and bone mineral density (BMD) loss in patients with spondyloarthropathies (SpAs).

METHODS

A cohort of 41 SpA patients were followed up for 4 years. Disease activity indices, spinal mobility and laboratory tests, BMD using were monitored at the baseline and 4-year follow-up. The 4% BMD loss at either of the proximal femurs was defined as significant.

RESULTS

Over the 4-year study period, 27% of SpA patients experienced femoral BMD loss. Baseline BMD>0.85g/cm(2) (p=0.011) was the baseline factor associated with BMD loss at 4-year follow-up. Several clinical and functional tests were helpful in identifying the BMD loss at follow-up: CRP>15.6mg/L (sens. 91%, spec. 70%), ESR>29mm/h (sens. 82%, spec. 73%), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI)>4.75 (sens. 91%, spec. 62%). At follow-up anti-TNFα treatment history, stable or improved lateral flexion and intermalleolar distance (NPV, accordingly, 95%, 88% and 87%), made BMD loss unlikely. Deterioration of the physician assessment of global disease activity (PAGDA) score from baseline to follow-up was a remarkable predictor of BMD loss (PPV=0.83), while stable or improved score excluded the BMD loss (NPV=0.83). According to multiple logistic regression analysis, baseline BMD value and follow-up CRP levels, when considered together, identify BMD status correctly in 85% of SpA patients (Nagelkerke R(2)=0.676).

CONCLUSION

Baseline BMD, anti-TNFα treatment, PAGDA score, spinal mobility tests and disease activity markers are useful factors in predicting the BMD loss in SpA patients and can provide surrogate information on BMD status.

The Relationship of Bone Mineral Density to Oxidant/Antioxidant Status and Inflammatory and Bone Turnover Markers in a Multicenter Cross-Sectional Study of Young Men with Ankylosing Spondylitis

Low bone mineral density (BMD) is an important complication of ankylosing spondylitis (AS) that seriously affects men and their quality of life, even in young patients. However, the relationships among redox; levels of bone turnover markers (BTMs), inflammatory markers and disease activity; and low BMD in AS require clarification. We recruited 102 men aged 30-39 year with AS and 102 healthy, sex- and age-matched controls for this cross-sectional study. The subjects were analyzed for lumbar spine and femoral neck BMD by dual-energy X-ray absorptiometry. Significantly lower BMD and corresponding T-scores were observed in the AS patients compared with the controls (P < 0.05). The oxidant biomarker and antioxidant levels were significantly (P < 0.05) higher and lower, respectively, in the AS subjects compared with the controls, and the bone resorption and inflammatory marker levels were higher (P < 0.05). In subgroup analyses, the patients with osteoporosis or active disease had the highest levels of oxidant biomarkers (P < 0.05). Furthermore, the BMD T-scores in AS were found to be negatively correlated with oxidative status (P < 0.05). Multivariate binary logistic analysis showed that low BMD in the AS patients was associated with higher levels of advanced oxidation protein products, malondialdehyde and C-terminal telopeptide of type I collagen; lower levels of glutathione peroxidase; and higher scores of a bath ankylosing spondylitis metrology index. In conclusion, imbalanced redox was independently associated with low BMD in young men with AS and may play an important role in the pathogenesis of AS-related low BMD.

Low levels of serum uric Acid increase the risk of low bone mineral density in young male patients with ankylosing spondylitis

OBJECTIVE

Uric acid (UA) has antiosteoporotic effects in postmenopausal women. This study investigated the association between serum UA levels and bone mineral density (BMD) in young male patients with ankylosing spondylitis (AS).

METHODS

One hundred fifty patients who fulfilled the modified New York criteria for the classification of AS were analyzed. All patients were male and under 50 years of age. BMD, serum UA concentrations, clinical variables, and radiographic progression were assessed. The associations between UA and BMD at the lumbar spine and hip were evaluated using multiple linear regression analysis. Multivariate logistic regression analyses were performed to identify risk factors associated with low BMD.

RESULTS

Mean serum UA concentration in the 150 patients with AS was 5.5 ± 1.3 mg/dl. BMD at the lumbar spine, but not at the total hip and femoral neck, increased with increasing serum UA tertiles (p = 0.033). The significant positive association between serum UA and BMD at the lumbar spine remained after adjustment for confounding factors (β = 0.185, p = 0.014, adjusted R(2) = 0.310). Multiple logistic regression analyses showed that lower UA concentrations (OR 4.02, 95% CI 1.34-12.3) and body mass index and increased erythrocyte sedimentation rate were independently associated with the risk of low BMD.

CONCLUSION

Lower serum UA levels are associated with lower BMD in young male patients with AS. UA may be a novel predictive marker or therapeutic target in patients with AS.

Bone mass in axial spondyloarthritis: A literature review

AIM: To review the published literature reporting bone loss in patients with axial spondyloarthritis (SpA) particularly those studies using dual X-ray absorptiometry (DXA) methods.

METHODS: This literature review examines the reported bone mass in patients with ax-SpA, particularly those using the DXA methods. The MEDLINE, Web of Science and Scopus databases were searched for relevant articles published between September 1992 and November 2013. Some of used search terms were ankylosing spondylitis (AS), SpA, spondyloarthropathy, bone loss, bone mass, osteopenia, bone mineral density, osteoporosis (OP), densitometry. Studies in which bone loss was investigated by using DXA in patients with SpA were eligible. Each article was reviewed and the key elements were noted.

RESULTS: There were 286 hits on MEDLINE, 200 on Web of Science and 476 on Scopus. After applying inclusion and exclusion criteria, we identified 55 articles in our systematic search. The sample size of the studies varied from 14 to 332 patients with SpA. The reported age range varied from 25 to 56 years in the reviewed studies. The symptom duration of patients with axSpA varied from 1.6 to 49 years. There were more males than females in these studies. Most of the recruited females were premenopausal women. Reported HLA-B27 positivity changed between 19% to 95%. The prevalence of OP and osteopenia in patients with SpA varied from 3%-47% to 5%-88%, respectively, in the included studies. In particular, the prevalence of OP and osteopenia ranged from 2.0%-47.0% and 5.0%-78.3%, respectively, in patients with AS. There are conflicting results regarding the relationship among disease activity, acute phase response and bone mass. Some studies suggest good correlation of bone mass with disease activity and acute phase reactants.

CONCLUSION: Bone loss may be determined in patients with axSpA at the lumbar spine or proximal femur even in the early phase of the disease and may be associated with inflammation (bone marrow edema) at the vertebral colon.

Ankylosing spondylitis confers substantially increased risk of clinical spine fractures: a nationwide case-control study

Ankylosing spondylitis (AS) leads to osteopenia/osteoporosis and spine rigidity. We conducted a case-control study and found that AS-affected patients have a 5-fold and 50% increased risk of clinical spine and all clinical fractures, respectively. Excess risk of both is highest in the first years and warrants an early bone health assessment after diagnosis.

INTRODUCTION

Ankylosing spondylitis (AS) is related to spine rigidity and reduced bone mass, but data on its impact on fracture risk are scarce. We aimed to study the association between AS and clinical fractures using a case-control design.

METHODS

From the Danish Health Registries, we identified all subjects who sustained a fracture in the year 2000 (cases) and matched up to three controls by year of birth, gender and region. Clinically diagnosed AS was identified using International Classification of Diseases, 8th revision (ICD-8; 71249), and International Classification of Diseases, 10th revision (ICD-10; M45) codes. We also studied the impact of AS duration. Conditional logistic regression was used to estimate crude and adjusted odds ratios (ORs) for non-traumatic fractures (any site, clinical spine and non-vertebral) according to AS status and time since AS diagnosis. Multivariate models were adjusted for fracture history, socio-economic status, previous medical consultations, alcoholism and use of oral glucocorticoids.

RESULTS

We identified 139/124,655 (0.11%) AS fracture cases, compared to 271/373,962 (0.07%) AS controls. Unadjusted (age- and gender-matched) odds ratio (OR) were 1.54 [95% confidence interval (95%CI) 1.26-1.89] for any fracture, 5.42 [2.50-11.70] for spine and 1.39 [1.12-1.73] for non-vertebral fracture. The risk peaked in the first 2.5 years following AS diagnosis: OR 2.69 [1.84-3.92] for any fracture.

CONCLUSIONS

Patients with AS have a 5-fold higher risk of clinical spine fracture and a 35% increased risk of non-vertebral fracture. This excess risk peaks early, in the first 2.5 years of AS disease. Patients should be assessed for fracture risk early after AS diagnosis.

Incidence and predictors of morphometric vertebral fractures in patients with ankylosing spondylitis

Introduction

Ankylosing spondylitis (AS) is associated with an increased incidence of vertebral fractures (VFs); however the actual incidence and predictors of morphometric VFs are unknown. The present study examined the incidence and predictors of new VFs in a large AS cohort.

Methods

In total, 298 AS patients who fulfilled the modified New York criteria were enrolled and spinal radiographs were evaluated biennially. Clinical and laboratory data and radiographic progression were assessed according to the Bath AS Disease Activity Index, erythrocyte sedimentation rate, C-reactive protein (CRP), and the Stoke AS spine score (SASSS). VF was defined according to the Genant criteria. The incidence of VFs at 2 and 4 years was evaluated using the Kaplan-Meier method. The age-specific standardized prevalence ratio (SPR) for AS patients in comparison with the general population was calculated.

Results

Of 298 patients, 31 (10.8%) had previous VFs at baseline. A total of 30 new VFs occurred in 26 patients over 4 years. The incidence of morphometric VFs was 4.7% at 2 years and 13.6% at 4 years. Multivariate logistic regression analysis showed that previous VFs at baseline and increased CRP levels at 2 years were predictors of new VFs (odds ratio (OR) =12.8, 95% confidence interval (CI) = 3.6-45.3 and OR = 5.4, 95% CI = 1.4–15.9). The age-specific specific standardized prevalence ratio of morphometric VFs in AS was 3.3 (95% CI 2.1–4.5).

Conclusions

The incidence of morphometric VFs increased in AS. Previous VFs and increased CRP levels predicted future VFs. Further studies are needed to identify the effects of treatment interventions on the prevention of new VFs.

Effect of TNF-alpha inhibitor treatment on bone mineral density in patients with ankylosing spondylitis: a systematic review and meta-analysis

OBJECTIVES

Ankylosing spondylitis (AS) is a chronic inflammatory disease associated with an increased risk of osteoporosis and fractures. TNF inhibitors have been used to treat AS, but their effect on bone is unclear. Thus, we conducted a meta-analysis to study the effect of TNF inhibitors on spine and hip BMD in patients with AS.

METHODS

Two authors independently searched MEDLINE and PubMed for longitudinal studies that had assessed the effect of TNF inhibitors on BMD in patients with AS. Studies with a minimum follow-up period of 1 year were included.

RESULTS

Seven longitudinal studies and one randomized control trial were included, with a total of 568 AS patients (mean age range of 36-48 years and disease duration of 9-17 years). Lumbar spine BMD increased by 5.1% (95% CI: 4.0-6.1%, p = 0.00000) after 1 year of treatment with TNF inhibitors and by 8.6% (95% CI: 6.8-10.3%, p < 0.00001) after 2 years. Significant improvements in total hip BMD were also noted after 1 [1.8% (1.0-2.5%)] and 2 years [2.5% (1.9-3.0%)]. Compared to baseline, femoral neck BMD remained stable after 1 year [0.7% (-0.8% to 2.2%), p = 0.34]. No significant heterogeneity was noted amongst the included studies.

CONCLUSIONS

TNF inhibitors can increase lumbar spine and total hip BMD and maintain femoral neck BMD for up to 2 years in patients with AS. More research is needed to assess the effect of TNF inhibitors on bone quality and fracture risk.

Initiation of tumor necrosis factor α antagonists and risk of fractures in patients with selected rheumatic and autoimmune diseases

OBJECTIVE

We tested the hypothesis that initiation of tumor necrosis factor α (TNFα) antagonists reduced the risk of fractures compared to nonbiologic comparators in patients with autoimmune diseases.

METHODS

Using 4 large administrative databases, we assembled retrospective cohorts of patients with autoimmune diseases who initiated either a TNFα antagonist or a nonbiologic medication. We identified 3 mutually exclusive disease groups: rheumatoid arthritis (RA), inflammatory bowel disease (IBD), and a combined group: psoriasis (PsO), psoriatic arthritis (PsA), or ankylosing spondylitis (AS). We used baseline covariate data to calculate propensity scores (PS) for each disease group and used Cox regression to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs). We compared the risk of combined hip, radius/ulna, humerus, or pelvic fractures between PS-matched cohorts of new users of TNFα antagonists and nonbiologic comparators.

RESULTS

We identified 9,020, 2,014, and 2,663 new PS-matched episodes of TNFα antagonist and nonbiologic comparator use in RA, IBD, and PsO-PsA-AS cohorts, respectively. The risk of combined fractures was similar between new users of TNFα antagonists and nonbiologic comparators for each disease (HR 1.17, 95% CI 0.91-1.51; HR 1.49, 95% CI 0.72-3.11; and HR 0.92, 95% CI 0.47-1.82 for RA, IBD, and PsO-PsA-AS, respectively). In RA, the risk of combined fractures was associated with an average daily dosage of prednisone equivalents >10 mg/day at baseline compared with no glucocorticoid (HR 1.54, 95% CI 1.03-2.30).

CONCLUSION

The risk of fractures did not differ between initiators of a biologic agent and a nonbiologic comparator for any disease studied. Among RA patients, use of >10 mg/day of prednisone equivalents at baseline increased the fracture risk.

Ankylosing spondylitis: from cells to genes

Ankylosing spondylitis (AS) is a chronic inflammatory disease of unknown etiology, though it is considered an autoimmune disease. HLA-B27 is the risk factor most often associated with AS, and although the mechanism of involvement is unclear, the subtypes and other features of the relationship between HLA-B27 and AS have been studied for years. Additionally, the key role of IL-17 and Th17 cells in autoimmunity and inflammation suggests that the latter and the cytokines involved in their generation could play a role in the pathogenesis of this disease. Recent studies have described the sources of IL-17 and IL-23, as well as the characterization of Th17 cells in autoimmune diseases. Other cells, such as NK and regulatory T cells, have been implicated in autoimmunity and have been evaluated to ascertain their possible role in AS. Moreover, several polymorphisms, mutations and deletions in the regulatory proteins, protein-coding regions, and promoter regions of different genes involved in immune responses have been discovered and evaluated for possible genetic linkages to AS. In this review, we analyze the features of HLA-B27 and the suggested mechanisms of its involvement in AS while also focusing on the characterization of the immune response and the identification of genes associated with AS.

Effects of anti-tumor necrosis factor α agents on bone

PURPOSE OF REVIEW

Tumor necrosis factor (TNF) inhibitors are effective for achieving disease control in several inflammatory diseases. Although anti-TNF agents can inhibit bone loss in vitro, their role in the prevention of clinically relevant outcomes such as osteoporosis and fractures has not been clearly established.

RECENT FINDINGS

There are many studies of the effects of TNF inhibitors on markers of bone turnover; however, few have measured bone mineral density (BMD) or fractures. Most of these studies have small sample sizes and a minority had a placebo control group. Overall these studies suggest that the antiresorptive effects of anti-TNF therapy are related to control of disease activity.

SUMMARY

The antiresorptive effects of TNF inhibitors are likely related to their anti-inflammatory properties. Studies to date have not demonstrated any advantages of TNF inhibitors over traditional nonbiologic therapies in the prevention of bone loss and fractures.

The paradoxical effects of TNF inhibitors on bone mineral density and radiographic progression in patients with ankylosing spondylitis

OBJECTIVES

To determine the longitudinal effects of TNF inhibitors on BMD and radiographic progression in patients with AS and to assess independent factors associated with increased BMD in the lumbar spine.

METHODS

Sixty-three patients with AS were included. Twenty-six patients were treated with TNF inhibitors and 37 were not. BMD in the lumbar spine and right femur was measured by DXA at baseline and 1 and 2 years later. Lumbar spine radiography was performed at baseline and after 2 years. Radiographic progression was scored using the Stoke AS Spinal Score (SASSS) and the modified SASSS. Univariate and multivariate linear regression analyses were performed to identify factors independently associated with spinal BMD increase.

RESULTS

BMD in the lumbar spine and total proximal femur of patients receiving TNF inhibitors increased consistently over 2 years compared with that in patients not receiving TNF inhibitors (P < 0.01 and P = 0.02), and treated patients showed increased SASSS scores (P = 0.05); however, syndesmophyte development was no different between the two groups. There was a significant difference in the change of SASSS in patients treated with both TNF inhibitors and bisphosphonates compared with those treated with TNF inhibitors alone (P < 0.01). TNF inhibitor therapy and the increase in SASSS were independently associated with increased lumbar spine BMD (P = 0.009 and P < 0.001).

CONCLUSION

TNF inhibitors appear to be associated with increased SASSS scores and improvements in BMD. Further prospective studies with larger subject numbers are needed to validate this paradoxical role of TNF inhibitors.

Bisphosphonates: focus on inflammation and bone loss

Bisphosphonates are pharmacological compounds that have been used for the prevention and treatment of several pathological conditions including osteoporosis, primary hyperparathyroidism, osteogenesis imperfecta, and other conditions characterized by bone fragility. Many studies have been performed to date to analyze their effects on inflammation and bone remodelling and related pathologies. The aim of this review is, starting from a background on inflammatory processes and bone remodelling, to give an update on the use of bisphosphonates, outlining the possible side effects and proposing new trends for the future. Starting from a brief introduction on inflammation and bone remodelling, we collect and analyze studies involving the use of bisphosphonates for treatment of inflammatory conditions and pathologies characterized by bone loss. Selected articles, including reviews, published between 1976 and 2011, were chosen from Pubmed/Medline on the basis of their content. Bisphosphonates exert a selective activity on inflammation and bone remodelling and related pathologies, which are characterized by an excess in bone resorption. They improve not only skeletal defects, but also general symptoms. Bisphosphonates have found clinical application preventing and treating osteoporosis, osteitis deformans (Paget's disease of bone), bone metastasis (with or without hypercalcaemia), multiple myeloma, primary hyperparathyroidism, osteogenesis imperfecta, and other conditions that feature bone fragility. Further clinical studies involving larger cohorts are needed to optimize the dosage and length of therapy for each of these agents in each clinical field in order to be able to maximize their properties concerning modulation of inflammation and bone remodelling. In the near future, although "old" bisphosphonates will reach the end of their patent life, "new" bisphosphonates will be designed to specifically target a pathological condition.

Biologicals and bone loss

Inflammatory joint diseases are associated with extra-articular side effects including bone involvement.There is an increased risk of osteoporotic fractures. The pathogeneses of local and generalized bone loss share a common pathway. Early and active rheumatoid arthritis is associated with longitudinal observed bone loss and fracture rate is of vertebral and nonvertebral fractures is doubled compared with matched healthy controls. Lowering disease activity with TNF inhibitors or is associated with stabilisation of bone mineral density by counteracting elevated bone resorption.

The DESIR cohort: a 10-year follow-up of early inflammatory back pain in France: study design and baseline characteristics of the 708 recruited patients

OBJECTIVES

The French Society of Rheumatology has initiated a large national multicenter, longitudinal, prospective follow-up of patients presenting with early inflammatory back pain in order to set up a database to facilitate several investigations on diagnosis, prognosis, epidemiology, pathogenesis and medico-economics in the field of early inflammatory back pain and spondyloarthritis.

METHODS

Patients were recruited if they had inflammatory back pain of more than 3 months and less than 3 years. Patients will be followed every 6 months during the first 2 years then every year during at least 5years. Apart from information collected on a Case Report Form (demographics, disease activity, severity, co-morbidities, socio-economics, treatments, radiological and MRI evaluation of the spine and the pelvis according to the local investigators, and for some centers bone densitometry and ultrasonography of entheses), the digital X-rays and MRI of the spine and pelvis are stored using a specific software (Carestream) and the biological samples (DNA, RNA, sera, urines) are centralized at the Biological Resources Center (Bichat Hospital).

RESULTS

The recruitment period of the 708 patients (mean age: 34±9years, female 54%, HLA-B27 positive: 57%) in the 25 centers was 26 months (from December 2007 to April 2010). The modified New York criteria, Amor criteria, ESSG criteria and axial ASAS criteria were fulfilled by 26%, 77%, 76% and 67% of the patients at entry, respectively. A history or current symptoms suggestive of peripheral arthritis, acute anterior uveitis and inflammatory bowel disease were observed in 21%, 9% and 4% of the patients, respectively. The disease was active (BASDAI: 45±20) despite an NSAID intake in 66% of the patients.

CONCLUSION

This large cohort should facilitate the conduct of researches in different areas (clinical, medico-economics, translational) in order to improve our knowledge on the pathogenesis and natural history of axial spondyloarthritis.