Osteopenia in men with mild and severe ankylosing spondylitis

The prevalence of vertebral fractures in diffuse idiopathic skeletal hyperostosis and ankylosing spondylitis: A systematic review and meta-analysis

Background

Subjects with ankylosing spinal disorders, including diffuse idiopathic skeletal hyperostosis (DISH) and ankylosing spondylitis (AS) are more prone to vertebral fractures and frequently present with neurological deficit compared to the patients without an ankylosed spine. Moreover, prevalent vertebral fractures are an important predictor for subsequent fracture risk. However, the pooled fracture prevalence for DISH is unknown and less recent for AS. We aimed to systematically investigate the prevalence and risk of vertebral fractures in DISH and AS populations.

Methods

Publications in Medline and EMBASE were searched from January 1980 until July 2023 for cohort studies reporting vertebral fractures in AS and DISH. Data on prevalence were pooled with random effects modeling after double arcsine transformation. Heterogeneity was assessed with I2 statistics and we performed subgroup analysis and meta-regression to explore sources of heterogeneity.

Results

We included 7 studies on DISH (n = 1,193, total fractures = 231) with a pooled vertebral fracture prevalence of 22.6% (95%CI: 13.4%-33.4%). For AS, 26 studies were included (n = 2,875, total fractures = 460) with a pooled vertebral fracture prevalence of 15.2% (95%CI: 11.6%-19.1%). In general, fracture prevalence for AS remained similar for several study-level and clinically relevant characteristics, including study design, diagnostic criteria, spine level, and patient characteristics in subgroup analysis. AS publications from 2010 to 2020 showed higher fracture prevalence compared to 1990 to 2010 (18.6% vs. 11.6%). Fractures in DISH were most common at the thoracolumbar junction, whereas for AS, the most common location was the mid-thoracic spine.

Conclusions

Vertebral fractures are prevalent in AS and DISH populations. Differences in fracture distribution along the spinal axis exist between the 2 disorders. Additional longitudinal studies are needed for incident fracture assessment in patients with ankylosing spinal disorders.

Advanced ankylosing spondylitis: a multisite, multimodality densitometric analysis for investigation of bone loss in the axial and appendicular skeleton

OBJECTIVE

The aim of this study was to investigate if there is a bias in bone mineral density measurements among major densitometric techniques across multiple skeletal sites.

METHODS

In 25 advanced ankylosing spondylitis patients, bone mineral density measurements were acquired in the lumbar spine, the hip, and the forearm.

RESULTS

In total, 60% of patients had a bone mineral density Z-score of -2 or less at one or more skeletal sites. Dedicated loss of cortical bone was identified at the distal forearm (60% of patients). Differences in bone mineral density measurements across all densitometric techniques were highly significant (p≤0.001). Bone loss was more striking in spinal trabecular bone by three-dimensional quantitative computed tomography [Z-score -2.1] versus dual-energy X-ray absorptiometry [Z-score 0]. A trabecular bone loss quantified by quantitative computed tomography was about twice as much as a cortical bone loss by single-energy X-ray absorptiometry (p=0.001).

CONCLUSIONS

Low bone mineral density is prevalent in advanced ankylosing spondylitis patients, predominating in the spine. Bone mineral density measurements have systematic differences when compared to each other. Knowledge of these offsets is useful for improved diagnosis of regional bone loss that allows for targeted treatment of osteoporosis. Three-dimensional quantitative computed tomography is more suitable for evaluating spinal osteoporosis in advanced ankylosing spondylitis than dual-energy X-ray absorptiometry, which rather underestimates bone loss.

Relationship between spinal structural damage on radiography and bone fragility on CT in ankylosing spondylitis patients

To evaluate whether the risk of bone fragility on computed tomography (CT) (scanographic bone attenuation coefficient of the first lumbar vertebra (SBAC-L1)) is associated with the severity of spine structural involvement (mSASSS) in patients with ankylosing spondylitis (AS). This retrospective study included AS patients, followed from 2009 to 2017, who fulfilled the New York criteria and who underwent thoraco-abdomino-pelvic CT and radiography (spine, pelvis). The structural involvement was retained for mSASSS ≥ 2. The SBAC-L1 was measured in Hounsfield units (HU). A SBAC-L1 ≤ 145 HU was used to define patients at risk of vertebral fracture (VF). A total of 73 AS patients were included (mean age: 60.3 (± 10.7) years, 8 women (11%), mean disease duration: 24.6 years (± 13.9)). Sixty patients (82.2%) had a mSASSS ≥ 2 (mean score 20.7 (± 21.2)). The mean SBAC-L1 was 141.1 HU (± 45), 138.1 HU (± 44.8) and 154.8 HU (± 44.9) in the total, mSASSS ≥ 2 and mSASSS < 2 populations, respectively. Patients with bone bridges had lower SBAC-L1 than mSASSS ≥ 2 patients without ankylosis (p = 0.02) and more often SBAC-L1 ≤ 145 HU (73% vs 41.9%, p = 0.006). A SBAC-L1 ≤ 145 HU was not associated with structural spine involvement, but patients with bone bridges had significantly decreased SBAC-L1 and an increased probability of being under the fracture threshold.

Vitamin D and Spondyloarthritis: Review of the Literature

Background:

Spondyloarthritides (SpAs) encompass heterogeneous diseases sharing similar genetic background, pathogenic mechanisms, and phenotypic features. Vitamin D is essential for calcium metabolism and skeletal homeostasis. Some recent evidences reported supplemental functions of vitamin D, such as modulation of inflammatory reactions.

Objective:

To analyze published data about a possible association between vitamin D and SpAs.

Results:

Vitamin D could play a role in immune reactions, influencing both immune and adaptive response. Vitamin D deficiency is more frequent in SpAs than in general population: an active and more severe disease infers patients’ mobility and reduces sunlight exposure. Quiescent inflammatory bowel disease, frequently associated with SpAs, could worsen vitamin D deficiency. All the parameters related to UVB exposure are the most important determinants for vitamin D status and need to be considered evaluating the vitamin D levels in SpAs.

Apart from musculoskeletal problems, patients affected by SpAs frequently suffer from other comorbidities, especially cardiovascular diseases and osteoporosis, and vitamin D status could have a relevance in this field. Bone is involved in SpAs with a dualistic role, coexisting trabecular bone resorption and new bone formation.

It seems rational to monitor vitamin D levels in SpA subjects and to target it to global health threshold.

Conclusion:

Literature data were not completely in agreement about a possible relation between poor vitamin D status and onset or worse disease course of SpAs. In fact, these results come from cross-sectional studies, which affect our ability to infer causality. Therefore, large, randomized controlled trials are needed.

Low incidence of vertebral fractures in early spondyloarthritis: 5-year prospective data of the DESIR cohort

OBJECTIVES

An increased risk of vertebral fractures (VFs) has been reported in spondyloarthritis (SpA). Our hypothesis is that the prevalence of VFs is lower than reported in previous studies, especially in early SpA. This study aimed at assessing the incidence of radiographical VFs over 5 years in early axial SpA.

METHODS

The DESIR (DEvenir des Spondylarthropathies Indifférenciées Récentes) cohort, which included patients with inflammatory back pain highly suggestive of axial SpA, is the basis of this study. All radiographs of the DESIR cohort had been assessed at a central facility, by one investigator specialised in the field of the diagnosis of VFs according to Genant's method. We assessed the prevalence and incidence of VFs and vertebral deformities at baseline and over 5 years.

RESULTS

Five-year X-rays were available for 432 patients (mean age 34.3±8.7 years, 53% women). Diagnosis of VF was doubtful and needed adjudication for 19 patients (4.4%). 13 patients had prevalent VFs (3.0%) which were located at the thoracic spine (12 were grade 1). At 5 years, five patients had an incident VF (1.15%); seven vertebrae were fractured, mostly located at the thoracic spine (n=6/7), and of grade 1 (n=6/7).

CONCLUSION

In the DESIR cohort, a population of early SpA, we found a low prevalence and incidence of VFs (3.0% and 1.15 %), respectively. This confirms our hypothesis that the actual prevalence and incidence of VFvertebral fracture in SpA is lower than that reported in the previous studies.

Bone Mineral Density and Fracture Risk in Ankylosing Spondylitis: A Meta-Analysis

We conducted a meta-analysis of studies to examine the risk of vertebral and non-vertebral fractures in patients with ankylosing spondylitis (AS). Additionally, we evaluated the risk factors of vertebral fractures in AS. Two authors independently searched Embase and Medline for studies that had assessed the risk of fractures in patients with AS. Twenty-two studies were eligible for the meta-analysis. Patients with AS had high frequency of vertebral fractures [OR (95% CI): 1.96 (1.52-2.51)]. Major risk factors for vertebral fractures in patients with AS include low BMD at the femoral neck and total hip, male gender, longer disease duration, higher BASDAI, higher BASRI, and possibly inflammatory bowel disease. The risk of non-vertebral fractures [OR (95% CI) 1.10 (1.04-1.15)] was 10% higher in AS patients than in controls. The risk of hip fractures in AS patients was not statistically significant [OR (95% CI) 1.17 (0.71-1.92)] in our pooled analysis. We found that patients with AS are at high risk of vertebral fractures. Male sex, duration of AS, mSASSS, BASRI, and low BMD at the hip and distal forearm were associated with the risk of vertebral fractures. Current evidence on the risk of hip fractures in patients with AS is inconsistent. Data about the effect of NSAIDs and TNF inhibitors on fracture risk in AS are limited.

Higher Level of Dickkopf-1 is Associated with Low Bone Mineral Density and Higher Prevalence of Vertebral Fractures in Patients with Ankylosing Spondylitis

Patients with ankylosing spondylitis (AS) have an increased risk of bone loss and vertebral fractures. In this study, we explored the hypothesis that the excess bone loss and vertebral fractures might be related with the activity of the Wingless signaling pathway, and in particular with the serum levels of its circulating inhibitors, Sclerostin and Dickkopf-1 (DKK1). We recruited 71 patients diagnosed with AS. Lateral radiographs of the total spine were analyzed to detect the presence of vertebral fractures, and bone mineral density (BMD) was assessed in all patients using dual X-ray absorptiometry at lumbar spine and proximal femoral site. Blood samples were obtained and levels of C-reactive protein (CRP), DKK1, and Sclerostin were measured. Blood samples from 71 healthy sex- and age-matched volunteers were collected to be used as controls. Vertebral fractures were detected more commonly among men than in women (29 vs 8 %, respectively). DKK1, but not Sclerostin serum levels, were inversely correlated to lumbar spine Z-score BMD. Patients with one or more prevalent vertebral fractures had significantly higher DKK1 levels, without significant difference in Sclerostin serum levels. A significant positive correlation was found between DKK1 serum levels and CRP (r = 0.240, p = 0.043). The association we found between serum DKK1 levels and BMD values and vertebral fracture prevalence suggests that DKK1 might contribute to the severity of osteoporosis in AS.

Utility of DXA scanning and risk factors for osteoporosis in ankylosing spondylitis-A prospective study

BACKGROUND

Conventional DXA imaging of spine and hip to measure bone mineral density (BMD) has limitations in patients with ankylosing spondylitis (AS). We investigated the correlation of hip and spine BMD measurements in patients with AS to determine if hip DXA will prove clinically useful while avoiding the confounding effect of spinal disease. Also, we studied risk factors for osteoporosis (OP) and osteopenia in AS.

METHODS

We randomly identified patients from our validated AS registry ≥18 years of age who met the Modified New York Classification criteria for AS. BMD was measured and interpreted using ISCD 2007 guidelines and diagnosis of OP was based on WHO criteria. ESR, CRP, urinary N-telopeptide, and 25-hydroxy vitamin D were also measured. Correlation between the BMD (total hip and/or femoral neck) and lumbar spine was calculated. Statistical comparisons between the 2 sites, lumbar spine (AP) and hip (total hip and or femoral neck) were made using Bowker's test for symmetry and kappa statistics. Chi-square and odds ratio using logistic regression were used to assess the association of the purported risk factors for OP in these patients.

RESULTS

Frequency of OP among AS patients ≥50 years of age was 23%, and that of osteopenia was 41%. Among patients <50 years of age, the frequency of low bone mass for expected age (Z-score ≤-2.0) was 14.7%. There was moderate correlation (ρ = 0.59) and a fair agreement (κ = 0.26; 95% CI: 0.10-0.42) between the lowest T-values of hip and lumbar spine (AP view). OP was significantly associated with elevated CRP level [OR = 4.2 (95% CI: 1.13-15.9), p < 0.03] and African American race [OR = 7.2 (95% CI: 1.18-44.99), p < 0.03].

CONCLUSION

Our results demonstrated a moderate correlation and fair agreement between the T-scores of hip and the lumbar spine (AP view) in patients with AS, suggesting that DXA of the hip and the lumbar spine (AP view) may both be useful for OP and osteopenia screening in patients with AS without fused spines. We confirm the previous reports of an association of elevated CRP level with an increased risk of OP in patients with AS, but this is the first study to demonstrate that African American patients with AS may be at a higher risk of developing OP compared to Caucasians.

Bone loss in patients with early inflammatory back pain suggestive of spondyloarthritis: results from the prospective DESIR cohort

OBJECTIVES

The objectives of the study were to assess the 2 year BMD changes and their determinants in patients with early inflammatory back pain suggestive of axial spondyloarthritis (SpA) (DESIR cohort).

METHODS

A total of 265 patients (54% male, mean age 34.4 years) had BMD measurements at baseline and at 2 years. Low BMD was defined as a Z score ≤-2 (at at least one site) and significant bone loss was defined by a decrease in BMD ≥0.03 g/cm(2). Clinical, biological and imaging parameters were assessed over 2 years.

RESULTS

Thirty-nine patients (14.7%) had low BMD at baseline; 112 patients (42.3%) had a 2 year significant bone loss. One hundred and eighty-seven (70.6%) used NSAIDs at baseline and 89 (33.6%) received anti-TNF therapy over 2 years. In anti-TNF users, BMD significantly increased at the lumbar spine and did not change at the hip site from baseline. In multivariate analysis, baseline use of NSAIDs [odds ratio (OR) 0.38, P = 0.006] had a protective effect on hip bone loss. In patients without anti-TNF treatments, baseline use of NSAIDs (OR 0.09, P = 0.006) and a 2 year increase in BMI (OR 0.55, P = 0.003) had protective effects on hip bone loss, whereas a 2 year increase in fat mass was associated with hip bone loss (OR 1.18, P = 0.046).

CONCLUSION

Among patients with symptoms suggestive of early axial SpA, 42.3% of patients have significant bone loss over 2 years. Anti-TNF therapy is protective against bone loss and baseline use of NSAIDs has a protective effect on hip bone loss.

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.

Serum Vitamin D and Pyridinoline Cross-Linked Carboxyterminal Telopeptide of Type I Collagen in Patients with Ankylosing Spondylitis

Objective. To assess the serum vitamin D and ICTP levels in patients with ankylosing spondylitis (AS) and investigate their relationship with disease activity and bone mineral density (BMD). Method. 150 patients and 168 controls were included. Serum 25(OH)D, ICTP, C-reaction protein (CRP), Bath AS Disease Activity Index (BASDAI), Bath AS Functional Index (BASFI), and Hip BMD were assessed in patients. 25(OH)D and ICTP were detected in controls. Results. The serum 25(OH)D in AS was 57.92 ± 24.42 nmol/L, significantly lower than controls (91.24 ± 42.02 nmol/L). Serum ICTP in AS was 5.72 ± 3.88 ug/L, significantly higher than controls (3.69 ± 1.26 ug/L). ICTP level was higher in men than in women patients (6.07 ± 4.05 versus 3.84 ± 1.96 ug/L, P ≤ 0.01); it was also higher in JAS than in AAS (9.52 ± 3.79 versus 5.27 ± 3.65 ug/L, P ≤ 0.01). Furthermore, 25(OH)D was negatively correlated with ICTP. Low 25(OH)D and high ICTP were one of the reasons of AS patients' low hip BMD. Besides, a significant relationship was found between serum ICTP and CRP. Conclusion. There was a high incidence of vitamin D inadequacy in AS. Serum ICTP level was elevated in AS, especially in JAS and male patients. 25(OH)D and ICTP seem to be valuable markers to detect bone loss in AS.

Bone mineral density in patients with symptoms suggestive of spondyloarthritis

Patients with axial spondyloarthritis (axSpA) have an increased risk of osteoporosis related to inflammation. We evaluate the performance of low bone mineral density (BMD) in diagnosis of axSpA for patients with symptoms suggestive of the disease. A low BMD (T ≤ -2) could be an additional tool for the diagnosis of axSpA.

INTRODUCTION

Diagnosis of axial spondyloarthritis (axSpA) can be challenging, especially in the absence of radiographic abnormalities. Patients with axSpA have an increased risk of osteoporosis related to inflammation. This study evaluated the performance of low bone mineral density (BMD) in diagnosis of axSpA for patients with symptoms suggestive of the disease.

METHODS

Medical files of patients that visited a tertiary centre for symptoms suggestive of axSpA were reviewed. Two hundred and sixty-seven patients were classified in confirmed axSpA or unconfirmed axSpA according to the diagnosis of a senior rheumatologist. BMD measurements results and percentage of patients with a low BMD (T ≤ -2) at either spine or hip were compared between the two groups. Diagnostic performances of low BMD (specificity, sensitivity, positive, negative predictive values and positive likelihood ratio (LR+)) were assessed.

RESULTS

Compared to patients with unconfirmed axSpA (n = 74), patients with confirmed axSpA (n = 193) had similar age, were more frequently male, with positive HLA B27, higher disease duration and higher C-reactive protein (CRP). Low BMD was more frequent at spine and hip, in patients with confirmed (40.3%) than unconfirmed axSpA (24.6%, p = 0.021). The LR+ of low BMD for an axSpA diagnosis was 2.60 and 3.12 at the spine and hip. In the subgroup of patients without any radiographic abnormalities (n = 128), the LR+ of low BMD for an axSpA diagnosis was 2.90 and 2.54 at the spine and hip.

CONCLUSION

In patients with symptoms suggestive of axSpA, a low BMD (T ≤ -2) could be an additional tool for the diagnosis of axSpA.

EULAR recommendations for the use of imaging in the diagnosis and management of spondyloarthritis in clinical practice

A taskforce comprised of an expert group of 21 rheumatologists, radiologists and methodologists from 11 countries developed evidence-based recommendations on the use of imaging in the clinical management of both axial and peripheral spondyloarthritis (SpA). Twelve key questions on the role of imaging in SpA were generated using a process of discussion and consensus. Imaging modalities included conventional radiography, ultrasound, magnetic resonance imaging, computed tomography (CT), positron emission tomography, single photon emission CT, dual-emission x-ray absorptiometry and scintigraphy. Experts applied research evidence obtained from systematic literature reviews using MEDLINE and EMBASE to develop a set of 10 recommendations. The strength of recommendations (SOR) was assessed by taskforce members using a visual analogue scale. A total of 7550 references were identified in the search process, from which 158 studies were included in the systematic review. Ten recommendations were produced using research-based evidence and expert opinion encompassing the role of imaging in making a diagnosis of axial SpA or peripheral SpA, monitoring inflammation and damage, predicting outcome, response to treatment, and detecting spinal fractures and osteoporosis. The SOR for each recommendation was generally very high (range 8.9–9.5). These are the first recommendations which encompass the entire spectrum of SpA and evaluate the full role of all commonly used imaging modalities. We aimed to produce recommendations that are practical and valuable in daily practice for rheumatologists, radiologists and general practitioners.

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.

Vitamin D in ankylosing spondylitis: review and meta-analysis

BACKGROUND

The role of vitamin D in ankylosing spondylitis (AS) is largely unknown. This paper aims to examine the association between serum vitamin D levels and susceptibility and disease activity of AS.

METHODS

We searched the relevant literatures in PubMed, Elsevier Science Direct, Chinese Biomedical Database (CBM), Chinese National Knowledge Infrastructure (CNKI) and Wanfang (Chinese) Database published before June 2014. Eight independent case-control studies with a total of 533 AS patients and 478 matching controls were selected into this meta-analysis. Standard mean differences (SMDs) with 95% confidence intervals (CIs) were used to assess the levels of serum vitamin D, parathyroid hormone (PTH), serum calcium and alkaline phosphatase (ALP) in cases and controls, respectively. Correlation coefficients (CORs) have been performed to value the correlationship between vitamin D and disease activity (erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI)) of AS patients.

RESULTS

Meta-analysis results suggested that vitamin D may play a protective role in AS (for total vitamin D: SMD=-0.71, P<0.001; for 25OHD: SMD=-0.66, P=0.002; for 1,25OHD: SMD=-0.72, P=0.19). Differences in PTH and serum calcium levels were not significant in AS (SMD=-0.10, P=0.67; SMD=0.12, P=0.17 respectively), while ALP was associated with AS susceptibility (SMD=0.20, P=0.04). The relationship between serum vitamin D levels and disease activity was statistically significant except for 25OHD versus (vs.) CRP or BASDAI (for CRP vs. 25OHD: COR=-0.22, P=0.08; for BASDAI vs. 25OHD: COR=-0.20, P=0.06, respectively).

CONCLUSION

The higher levels of serum vitamin D were associated with a decreased risk of AS, and showed an inverse relationship with AS activity.

Increase in bone density in patients with spondyloarthritis during anti-tumor necrosis factor therapy: 6-year followup study

OBJECTIVE

To assess the effects on bone mineral density (BMD) of prolonged anti-tumor necrosis factor (anti-TNF) therapy in patients with spondyloarthritis (SpA); to compare the BMD changes to those observed in SpA patients not treated with anti-TNF; and to identify the predictors of these changes.

METHODS

Fifty-nine patients with SpA according to the European Spondylarthropathy Study Group criteria who were treated with anti-TNF therapy for at least 4 years were included. Thirty-four patients with SpA from an international longitudinal observational study (OASIS cohort) were used as a control group. Lumbar spine and hip BMD were measured by dual-energy x-ray absorptiometry at baseline, after 1 year, and after at least 4 years.

RESULTS

Over an average 6.5 years' followup, the increase in BMD was 11.8% (± 12.8%) at the lumbar spine (p < 0.0001) and 3.6% (± 9.3%) at the great trochanter (p = 0.0001) in patients treated with anti-TNF. At the lumbar spine, the increase was similar in patients with and those without syndesmophytes. BMD changes were significantly higher in the anti-TNF group than in the control group at lumbar spine (p < 0.0001), at femoral neck (p = 0.002), and at trochanter (p = 0.011), but not at total hip (p = 0.062). Multivariate analysis showed that the predictors of lumbar spine BMD changes in the total population were the use of anti-TNF (p < 0.0001) and, in the anti-TNF therapy group, the 1-year lumbar spine BMD change (p = 0.007).

CONCLUSION

This study shows that prolonged anti-TNF therapy increases lumbar spine and trochanter BMD. This effect should be taken into account before introducing antiosteoporotic treatment in these patients.

Bone oedema on MRI is highly associated with low bone mineral density in patients with early inflammatory back pain: results from the DESIR cohort

OBJECTIVES

To assess bone mineral density (BMD) at lumbar spine and hip in a large cohort of patients with early inflammatory back pain (IBP) suggestive of axial spondyloarthritis (SpA), and to assess systemic and bone inflammation (according to MRI) as risk factors of low BMD.

PATIENTS AND METHODS

332 (52.4% male) patients with IBP suggestive of axial SpA defined by Calin or Berlin criteria were recruited; they had lumbar spine and hip BMD and body composition measurements. Low BMD was defined by Z≤-2 (at least one site). Clinical, biological (erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)) and imaging (x-rays, spine and sacroiliac joint MRI) parameters were compared in patients with and without low BMD (Z≤-2). Significant parameters in univariate analysis were tested in multivariate models.

RESULTS

Patients (mean age 33.8 years) had a short duration of axial symptoms (mean 1.6 years); 71.4% fulfilled the Assessment of Spondyloarthritis International Society criteria for axial SpA and HLA-B27 was present in 62.1%. 43 (13.0%) had low BMD (88% male). Multivariate logistic regression showed that parameters significantly associated with low BMD (any site) were the presence of bone marrow oedema (inflammatory lesions) on MRI (OR 4.63, p=0.001), either ESR or CRP (OR 2.60, p=0.037) and male gender (OR 9.60, p=0.0004).

CONCLUSIONS

This study conducted in a large cohort of young adults with early IBP suggestive of SpA shows that 13.0% of patients have a low BMD and that the main risk factor associated with low BMD was inflammation on MRI.

The epidemiology of osteoporosis and fractures in ankylosing spondylitis

Bone is a target in many inflammatory rheumatic diseases. Inflammation leads to a wide range of changes in bone, and especially bone remodeling. In ankylosing spondylitis (AS) bone loss has been documented, but measuring bone density in the spine is hampered by new bone formation in syndesmophytes, periost and within the vertebrae. The risk of vertebral fractures is increased in AS. The diagnosis of vertebral fractures requires imaging and adequate evaluation of vertebral heights. In addition, in the ankysosed spine segments, additional imaging is often needed to diagnose spinal fractures at unusual locations (cervical spine) or in the posterior arch structures. Risk factors for vertebral fractures are helpful for case finding. Fracture prevention is indicated in high risk patients with AS, especially when they have already a vertebral fracture or in the presence of osteoporosis.

Bone tissue metabolism in men with ankylosing spondylitis

PURPOSE

The aim of the study was the composite estimation of bone tissue metabolism in ankylosing spondylitis (AS) after having taken into account such factors as a high risk of incidence of osteoporosis in patients with AS and potential danger of permanent immobility.

MATERIAL AND METHODS

Sixty-six patients with established diagnosis of AS and 63 healthy individuals in the control group were included into the study. To measure bone mineral density (BMD) the dual energy X-ray absorptiometry (DEXA) method was used. Additionally, biochemical markers of osteoporosis such as bone fraction of an alkaline phosphatase (BALP), osteocalcin (BGP) and deoxypyridinoline (Dpd) as well as many inflammatory markers of disease activity have been determined.

RESULTS

In our study with AS had significantly diminished bone mineral density, as compared with health controls. The presence of osteopenia/osteoporosis was associated with longer duration of the disease and with higher age. In the overall group of AS patients bone degradation marker, Dpd, correlated with serum concentration of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha) and C-reactive protein (CRP), and inversely with BMD measured in the forearm. However, no direct association could be revealed between lower bone density and markers of inflammation or inflammatory cytokines, except of IL-6 witch was significantly higher in AS patients with osteoporosis/osteopenia than those without.

CONCLUSIONS

Our results indicate that disease duration and higher age are risk factors for osteoporosis in patients with AS. Inflammation might contribute to the accelerated bone loss in AS through stimulation of bone degradation.

High prevalence of low bone mineral density in patients within 10 years of onset of ankylosing spondylitis: a systematic review

Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease. Decreased bone mineral density (BMD) is a common complication of AS, with a prevalence range of 19 to 62 %. Many studies have shown decreased BMD in AS with long disease duration, but only a few studies investigated BMD in early AS. The prevalence of decreased BMD in early disease stages of AS has not yet been clearly described, and for that reason, we reviewed the literature which describes the prevalence of decreased BMD in AS patients with a short disease duration (<10 years). In this review, we included articles which used the modified New York criteria for the diagnosis of AS, included patients with a disease duration of less than 10 years, and used the WHO criteria for osteopenia and osteoporosis. Decreased BMD was defined as a T score < −1.0, including both osteopenia and osteoporosis. For this review, only articles that acquired BMD data of lumbar spine and femoral neck by DXA were used. The literature search provided us 35 articles of which 7 matched all our criteria, and they will be further outlined in this review. The overall prevalence of decreased BMD of the articles reviewed is 54 % (n = 229/424) for lumbar spine and 51 % (n = 224/443) for femoral neck. The prevalence of osteopenia vs. osteoporosis for lumbar spine is 39 vs. 16 % and for femoral neck, 38 vs. 13 %. This review showed a high total prevalence of 51–54 % decreased BMD and 13–16 % osteoporosis in AS with a short disease duration. This high prevalence was not to be expected in a relatively young and predominantly male population. Further research is needed to determine the clinical relevance of this low BMD by investigating the relation between low BMD and vertebral and nonvertebral fractures at this early stage in AS.

The effect of three years of TNFα blocking therapy on markers of bone turnover and their predictive value for treatment discontinuation in patients with ankylosing spondylitis: a prospective longitudinal observational cohort study

Introduction

The aim of this study was to investigate the effect of three years of tumor necrosis factor-alpha (TNF-α) blocking therapy on bone turnover as well as to analyze the predictive value of early changes in bone turnover markers (BTM) for treatment discontinuation in patients with ankylosing spondylitis (AS).

Methods

This is a prospective cohort study of 111 consecutive AS outpatients who started TNF-α blocking therapy. Clinical assessments and BTM were assessed at baseline, three and six months, as well as at one, two, and three years. Z-scores of BTM were calculated to correct for age and gender. Bone mineral density (BMD) was assessed yearly.

Results

After three years, 72 patients (65%) were still using their first TNF-α blocking agent. In these patients, TNF-α blocking therapy resulted in significantly increased bone-specific alkaline phosphatase, a marker of bone formation; decreased serum collagen-telopeptide (sCTX), a marker of bone resorption; and increased lumbar spine and hip BMD compared to baseline. Baseline to three months decrease in sCTX Z-score (HR: 0.394, 95% CI: 0.263 to 0.591), AS disease activity score (ASDAS; HR: 0.488, 95% CI: 0.317 to 0.752), and physician's global disease activity (HR: 0.739, 95% CI: 0.600 to 0.909) were independent inversely related predictors of time to treatment discontinuation because of inefficacy or intolerance. Early decrease in sCTX Z-score correlated significantly with good long-term response regarding disease activity, physical function and quality of life.

Conclusions

Three years of TNF-α blocking therapy results in a bone turnover balance that favors bone formation, especially mineralization, in combination with continuous improvement of lumbar spine BMD. Early change in sCTX can serve as an objective measure in the evaluation of TNF-α blocking therapy in AS, in addition to the currently used more subjective measures.

Relationship of bone mineral density with disease activity and functional ability in patients with ankylosing spondylitis: a cross-sectional study

In ankylosing spondylitis, inflammatory activity probably plays a key role in the pathophysiology of bone loss. The aim of the study was to investigate the relationship of bone mineral density (BMD) at the lumbar spine and hip region with some measures of disease activity and functional ability in patients with ankylosing spondylitis. In 80 patients with established ankylosing spondylitis, disease activity and functional ability were determined by C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI). Spinal pain and patient global health were assessed using horizontal visual analog scale. BMD was measured by dual-energy X-ray absorptiometry. There was a significant negative correlation of bone density T scores with acute-phase reactants (i.e., patients with lower T scores had higher level of CRP and ESR). That relationship was reflected more reliably at proximal femur sites than at the lumbar spine. There were also significant differences in ESR, BASDAI, BASFI, spinal pain and global health between three groups of patients according to WHO classification of osteoporosis (normal, osteopenic and osteoporotic). Significantly, more patients with osteopenia at the lumbar spine had lower BASDAI index than those with normal BMD (P = 0.030). Our results indicate an association of low BMD with high disease activity in patients with AS. Femoral BMD seems to be more associated with disease activity and functional ability than lumbar spine BMD.

The relation between bone mineral density, bone turnover markers, and vitamin D status in ankylosing spondylitis patients with active disease: a cross-sectional analysis

SUMMARY

Osteoporosis is a well recognized complication of ankylosing spondylitis (AS). This study indicates that increased bone turnover, inflammation, and low vitamin D levels are important in the pathophysiology of AS-related osteoporosis, and that bone turnover markers (BTM) are valuable markers to detect bone loss in AS.

INTRODUCTION

The aim of this study was to elucidate the pathophysiology of AS-related osteoporosis by investigating the relation between bone mineral density (BMD), BTM, vitamin D, and clinical assessments of disease activity and physical function, as well as to identify parameters that are related to low BMD (osteopenia or osteoporosis) in AS patients with active disease.

METHODS

One hundred twenty-eight consecutive Dutch AS outpatients were included in this cross-sectional study. Bath AS Disease Activity Index (BASDAI), erythrocyte sedimentation rate (ESR), C-reactive protein, ASAS-endorsed disease activity score (ASDAS), Bath AS Functional Index (BASFI), bone formation markers procollagen type 1 N-terminal peptide (PINP) and osteocalcin (OC), bone resorption marker serum C-telopeptides of type I collagen (sCTX), 25-hydroxyvitamin D (25OHvitD), lumbar spine and hip BMD, and vertebral fractures were assessed. Z-scores of BTM were calculated using matched 10-year cohorts of a Dutch reference group to correct for the normal influence that age and gender have on bone turnover.

RESULTS

sCTX Z-score, OC Z-score, BASDAI, age, and gender were independently related to low BMD. In addition, PINP Z-score, ESR, 25OHvitD, age, and gender were independently related to sCTX and/or OC Z-score.

CONCLUSIONS

This study indicates that increased bone turnover, inflammation, and low vitamin D levels are important in the pathophysiology of AS-related osteoporosis. Furthermore, sCTX and OC Z-scores seem to be valuable markers to detect bone loss in AS patients in daily clinical practice where BMD of the lumbar spine, measured by DXA, may be overestimated due to osteoproliferation in patients with advanced AS.

Osteoporosis in ankylosing spondylitis

Osteoporosis (OP) is a frequent complication of ankylosing spondylitis (AS), even in early stages of the disease, and is associated with elevated levels of biochemical markers of bone turnover, proinflammatory cytokines, and acute-phase reactants. This suggests that systemic inflammatory mediators, such as interleukin-6 and tumor necrosis factor-alpha, may be involved. Various factors that conceivably work in conjunction with one another also cause bone loss in AS (eg, genetic polymorphisms of vitamin D, low levels of osteoprotegerin and sex steroid hormones, and impaired calcium and vitamin D absorption). Dual x-ray absorptiometry for assessing bone mineral density (BMD) has limitations in patients with AS because of unreliability of spinal measurements, particularly in advanced disease with new bone formation. Femoral neck BMD is reduced and correlates with increased risk of vertebral fractures. Hence, measurement of BMD at the femoral neck may provide the most accurate means of detecting osteopenia and OP and could assess fracture risk in AS patients. No guidelines are available for detection and treatment of OP in AS, and most patients are young men, who are less likely to be screened. The only evidence-based recommendation is that optimal control of disease activity in AS prevents bone loss. A recent study showed a beneficial effect of infliximab therapy on bone turnover markers and BMD in AS. Also, bisphosphonates may be useful in managing OP in AS.

Bone mineral density in young males with ankylosing spondylitis

OBJECTIVE

To assess bone mineral density (BMD) abnormalities in young Indian males with ankylosing spondylitis (AS) and factors influencing this.

METHODS

Eighty AS male subjects were compared with 160 age/sex matched controls for BMD of lumbar spine and proximal femur. AS subjects were evaluated and followed up every 3 months for disease activity. BMD was estimated at spine and proximal femur using the dual-energy X-ray absorptiometry (DXA) technique.

RESULTS

All subjects were males with mean age of 32.9 ± 8.3 years and mean duration of disease was 8.1 ± 5.8 years. AS subjects had significantly lower BMD at the spine and femur as compared with controls (both P < 0.001). Using WHO standards, osteoporosis (OP) in spine and femur neck was seen in 28.75% (controls: 1.84%, P < 0.001) and 11.54% (controls: 1.23%, P < 0.001), respectively. No statistically significant difference in prevalence of OP was seen with disease duration, C-reactive protein levels and disease activity indices (all P > 0.05). Syndesmophytes were seen in 22.5% (n = 18) of AS subjects. There was no significant difference between BMD values at spine in AS subjects with or without syndesmophytes (0.91 + 0.16 g/cm(2) vs. 0.90 + 0.14 g/cm(2), P = 0.79).

CONCLUSION

OP is a significant complication in AS even in young males with early disease, and more prevalent in the spine compared to femur. In our study, BMD was not influenced by disease activity indices, inflammatory markers or total disease duration. Spinal BMD is the most sensitive site for defining OP in AS.

[Bone densitometry in inflammatory rheumatic diseases : Characteristics of the measurement site and disease-specific factors]

Bone densitometry should be performed earlier in patients with inflammatory arthritis, since factors such as inflammation and drug therapy, in particular treatment with glucocorticoids, have an important impact on the development of osteoporosis. DXA (Dual energy X-ray Absorptiometry) is considered the gold standard for bone densitometry. According to the German guidelines for osteoporosis, bone densitometry plays a crucial role in the choice of therapy.In patients with rheumatoid arthritis, measurement of peripheral bone (forearm) density in addition to lumbar spine and hip is recommended, since local bone loss is pathognomonic for this disease. DXA measurements of the hand enable the diagnosis of juxtaarticular osteoporosis at an earlier stage; however, this has not yet been established in routine practise.Bone measurement in patients with ankylosing spondylitis can be performed in the lumbar spine and the hip at disease onset. In systemic lupus erythematosus, bone loss is more frequent in patients with high inflammatory activity. Patients with psoriasis arthritis frequently have osteoporosis in the case of a destructive development of the joints.

Relationship Between Bone Mineral Density and Disease Activity in Patients with Ankylosing Spondylitis

Objective: This retrospective study was planned to determine the relationship between bone mineral density (BMD) and clinical, radiological and laboratory parameters in patients with ankylosing spondylitis (AS).

Materials and Methods: The study group consisted of 28 patients with a mean disease duration of 11.9±6.1 years. In addition to clinical and demographic variables, lumbar and femoral BMD were evaluated with dual energy X-ray absorbtiometry. Lumbar spine score (LSS) and sacroiliac score (SIS) were calculated by grading of standard radiographs. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level were determined as laboratory parameters.

Results: The rate of osteoporosis and osteopenia were 7.1% and 25% at the lumbar spine, and 14.2% and 17.8% at the femoral neck, respectively. LSS was significantly correlated with lumbar BMD (r=0.70, p<0.001), but not with femoral neck BMD (r=-0.11, p=0.55). SIS was negatively correlated with femoral neck BMD (r=-0.79, p<0.001), but not correlated with lumbar BMD (r=0.19, p=0.32). While lumbar BMD was positively correlated with disease duration (r=0.37, p=0.05), femoral neck BMD showed negative correlation with disease duration (r=-0.46, p=0.01). The evaluation of clinical paramaters and BMD showed that morning stiffness, spinal pain, ESR and CRP were not correlated with BMD. Only modified Schober's test was related to BMD on both lumbar spine and femoral neck.

Conclusion: Ankylosing spondylitis patients are at risk for developing osteoporosis. In advanced disease, the lumbar BMD is misleadingly high because of paravertebral calcification and ossification. Therefore, it is more rational to evaluate the BMD at the femoral neck. (Turk J Rheumatol 2010; 25: 24-8)

Bone and cartilage turnover markers, bone mineral density, and radiographic damage in men with ankylosing spondylitis

PURPOSE

To determine the levels of bone and cartilage turnover markers in men with ankylosing spondylitis (AS) and to investigate their associations with disease activity, bone mineral density, and radiographic damage of the spine.

PATIENTS AND METHODS

This cross-sectional study enrolled 35 men with newly diagnosed AS. The bone mineral densities (BMD) of their lumbar spines and proximal femurs, Bath AS Disease Activity Index (BASDAI), and Bath AS Radiographic Index (BASRI) were evaluated. Urinary C-terminal telopeptide fragments of type I collagen (CTX-I) and type II collagen (CTX-II) levels were determined by enzyme-linked immunosorbent assay, and serum levels of bone-specific alkaline phosphatase (BALP) and osteocalcin were determined by an enzyme immunoassay. Levels of biochemical markers were compared with those of 70 age-matched healthy men.

RESULTS

Patients with AS had significantly higher mean urinary CTX-I and CTX-II levels than control subjects (p<0.05). Elevated urinary CTX-I levels correlated well with BASDAI, femoral BMD, and femoral T score (p<0.05), and elevated urinary CTX-II levels correlated well with spinal BASRI (p<0.05) in patients with AS. Mean serum BALP and osteocalcin levels did not differ between patients and controls and did not show any significant correlations with BMD, BASDAI, or BASRI in men with AS.

CONCLUSIONS

Elevated CTX-I reflects disease activity and loss of femoral BMD while elevated CTX-II levels correlate well with radiographic damage of the spine, suggesting the usefulness of these markers for monitoring disease activity, loss of BMD, and radiographic damage in men with AS.

Advances in musculoskeletal imaging and their clinical utility in the early diagnosis of spondyloarthritis

Interest in imaging ankylosing spondylitis (AS) and related spondyloarthropathies has increased in recent years. MRI is regarded as the most sensitive imaging modality to detect early inflammatory lesions in the sacroiliac joints and in the spine. Standard radiography plays a major role in evaluating potential disease-modifying properties of the recently introduced, symptomatically effective anti-tumor necrosis factor-alpha agents. Various radiographic scoring methods have been developed to assess and monitor spinal structural damage in AS. The modified stoke ankylosing spondylitis spine score is the method of choice based on its sensitivity to change. MRI is emerging as a useful tool to detect AS early, but this remains a challenge. Recent progress in MR technology with the advent of whole body MRI has expanded the potential role of imaging in AS. Further data are needed before MRI can replace radiographs for earlier diagnosis of AS.

Osteoporosis and vertebral fractures in ankylosing spondylitis

PURPOSE OF REVIEW

To review recent data, in the context of what is already known, about an increased risk of vertebral fractures in ankylosing spondylitis patients.

RECENT FINDINGS

Osteoporosis and fractures of the vertebral body and its dorsal arch are now well recognized features in patients with ankylosing spondylitis, but their diagnosis is still often a challenge. The risk factors and clinical consequences for fractures in ankylosing spondylitis are increasingly understood in the context of osteoimmunology and of spinal biomechanical changes in material and structural components in the spine that result in bone failure.

SUMMARY

Diagnosing fractures of the vertebral body and its dorsal arch remains a challenge in studies and in clinical practice. Prospective studies are needed to evaluate to what degree such fractures can be prevented in ankylosing spondylitis.

Seronegative Spondyloarthropathy – Studies from the Asia Pacific Region

Recent therapeutic advances, in particular the use of anti-tumour necrosis factor (anti-TNF) agents, have revived interest in the seronegative spondyloarthropathies (SpA), a group of arthritides characterised by axial skeletal involvement and the absence of rheumatoid factor. The purpose of this article is to review the studies that have been done in the Asia Pacific region, as a broad understanding of the scope and severity of this group of diseases would enable rheumatologists and physicians in this part of the world to better manage their patients. The majority of genetic studies have focused on the associations of HLA-B27 with ankylosing spondylitis (AS) and SpA, while a few studies examined the associations of the CARD, IL-1, LMP2, TAP and TGF with AS. There are a handful of studies on the immunological responses to bacteria and cytokine levels in AS. The onset and clinical features of SpA have been reported from most countries in the region, but no data on patient outcomes, using current measurement tools such as the Bath Ankylosing Spondylitis Disease Activity index (BASDAI), is available. Validation of these instruments of measurement as well as classification criteria in different ethnic populations is necessary where no prior data exist. Future studies will likely be focused on better clinical characterisation of patient cohorts, particularly with regard to the use of currently used measurement tools for disease activity and spinal function and mobility, and the identification of the need for biologic therapy in each country. Key words: ESSG criteria, Genetics, Immunological and clinical features

Epidemiology of Osteoporosis in Rheumatic Diseases

Much work has been directed at establishing the impact of osteoporosis and related fragility fractures in rheumatic diseases. Several cross-sectional studies reported that disability and reduced motility that are due to functional impairment are among the most important determinants of bone loss in different rheumatic diseases. At the same time, longitudinal studies have confirmed the detrimental effect of uncontrolled disease activity on bone density. In this perspective, the suppression of inflammation probably remains the main concern when considering treatment options. Besides these variables, pharmacologic agents that are used commonly in the treatment of these conditions probably have an adjunctive effect on bone loss in rheumatic patients. Large epidemiologic studies have demonstrated clearly that patients who have RA, SLE, or AS are at an increased risk for fragility fractures. Further studies are required to investigate the effective impact of osteoporosis and fragility fractures in other rheumatic diseases, and to define the relationship between OA and osteoporosis. A better appreciation of the impact and mechanisms of osteoporosis in rheumatic diseases by rheumatologists represents a clinical challenge; however, a greater understanding of this frequent complication will improve the quality of health care and the lives of patients who have rheumatic diseases.