Hand bone densitometry: a more sensitive standard for the assessment of early bone damage in rheumatoid arthritis

Whole-hand and regional bone mineral density involvement in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by symmetric polyarthritis that can lead to joint deformity, disability, and osteoporosis. We aimed to evaluate whole hand and regional BMD in RA patients compared to controls. In addition, we evaluated the BMD of dominant versus non-dominant hands in healthy subjects. We included adult female and male RA patients and control subjects matched by age, sex, and BMI. BMD (g/cm2) was measured by DXA in lumbar spine (LS), whole hand, and three regions of interest: carpus, metacarpal bones, and phalanges. Results: 44 control subjects (49.5±11.8 y) and 60 with RA (52.7±12.7 y) were included. Significant lower BMD in RA patients was found in LS (-8.7%), dominant whole hand (-9.5%), carpus, metacarpal bones, and phalanges, and non-dominant whole hand (-8.7%), metacarpal bones, and phalanges compared to controls. A significant positive correlation was found between LS and whole-hand BMD (dominant r=.63, non-dominant r=.67). Finally, the whole hand, metacarpal bones, and carpus BMD measurements were significantly higher in the dominant hand compared to the non-dominant hand without differences in the phalangeal ROI. In conclusion, hand BMD was significantly lower in RA patients compared to control subjects and there was a significant correlation with LS BMD. We demonstrated that BMD measurements of the whole-hand, and different ROI (carpus, metacarpal bones, and phalanges) by DXA would be an easily reproducible technique to evaluate bone loss. In addition, the whole hand, metacarpal bones and carpus BMD measurements were significantly higher in the dominant hand compared to the non-dominant hand without differences in the phalanges.

Factors associated with hand bone changes in early rheumatoid arthritis

BACKGROUND

The aim of this research was to assess if hand bone mineral density (HBMD) changes associated with the appearance of erosions in early rheumatoid arthritis (ERA), compared with the population-based control group. Additionally, we tried to identify if there are novel factors that associate with HBMD and erosive changes (EC), and if they are dissimilar. The study was conducted as the data are limited.

METHODS

The study group consisted of 83 ERA patients and 321 controls. Dual-Energy X-Ray Absorptiometry (DXA) machine was used to measure HBMD. EC of RA (rheumatoid arthritis) were assessed in X-rays of hands using Sharp scores. Life-style habits, inflammation markers were assessed to evaluate the effects of different factors.

RESULTS

The presence of ERA was associated with lower HBMD compared with controls (adjusted for age, gender, height and weight; b -0.01, p = 0.045). 76% (95% CI 65.3-84.6) of ERA patients had EC in hand X-ray. Smoking habits and higher BMI (body mass index) were associated with an increased likelihood of having RA specific EC. In ERA, decreasing of HBMD was associated with the elevation of interleukin-6 (IL-6) and rheumatoid factor (RF) positivity.

CONCLUSIONS

In ERA, HBMD changes were not associated with the appearance of erosions. Factors that associate in ERA with HBMD changes and appearance of erosions differ. HBMD assessment together with serum IL-6 level could be useful in everyday clinical practice for better surveillance of ERA patients who do not have EC in hand X-rays.

Exploring the Differences Between Dominant and Nondominant Feet and Hands Bone Mineral Density

The assessment of regional bone mineral density (BMD) has proved to be useful for illustrating the impact of focal bone demineralization diseases on bone mass. In these scenario, a common practice is to compare the affected limb with the contralateral limb. However, there are no studies comparing BMD differences between dominant vs nondominant limbs at these sites. In addition, most studies have assessed BMD in specific ROIs (regions of interests) instead of in the whole limb. The purpose of our study was to compare the BMD of dominant vs nondominant hands and feet in healthy individuals, using both the whole limb software and specific ROIs. We performed a cross-sectional analysis on untrained women and men over 18 years of age who volunteered to participate. BMD (g/cm²), bone area (cm²) and BMC (bone mineral content) (g) were measured by Lunar Prodigy DXA (GE Healthcare, Madison, WI, USA), using 2 different approaches: whole limb/region software and specific ROIs. A total of 42 subjects (11 men and 31 women) were included. Mean age was 44.19 ± 10.49 years. BMD was greater in the dominant in comparison with the nondominant hand. The difference was 0.014 (95% CI, 0.009-0.018) for the whole hand BMD, 0.023 (95% CI, 0.003-0.044) for ROI 1, and 0.016 (95% CI, 0.003-0.029) for ROI 2. No significant differences were found between dominant and nondominant foot BMD, using the whole limb software and specific ROIs. To our knowledge, this is the first study to explore the differences in BMD, bone area and BMC in terms of limb dominance, supporting the usefulness of DXA as an accurate and objective complementary diagnostic or follow-up tool in focal bone demineralization diseases.

A comparative analysis of articular bone in large cohort of patients with chronic inflammatory diseases of the joints, the gut and the skin

Chronic inflammatory diseases are associated with bone loss. While the occurrence of systemic bone loss is well described in chronic inflammatory diseases, the impact of these conditions on articular bone has not been systematically investigated. Recent refinements in high-resolution CT assessment of the joints now allow the accurate measure of articular bone composition. In this study 476 subjects comprising healthy individuals and patients with anticitrullinated protein antibody (ACPA)-positive rheumatoid arthritis (RA), ACPA-negative RA, Crohn's disease (CD), ulcerative colitis (UC), psoriasis (PsO) and psoriatic arthritis (PsA) were subjected to high-resolution quantitative computed tomography (HR-pQCT) of the hand. Metacarpal heads were assessed for total, trabecular and cortical volumetric bone mineral density (vBMD). Only ACPA+RA, but not the remaining inflammatory diseases (ACPA-RA, CD, UC, PsO, PsA) showed significant (p < 0.001) loss of articular bone affecting both the trabecular and the cortical compartments. Age and body mass index were also associated with articular bone changes, the former with lower, the latter with higher articular bone mass. In multivariate models, presence of ACPA+RA was an independent factor for articular bone loss. Among chronic inflammatory diseases ACPA+RA is the most potent precipitator for articular bone loss pointing out the role of autoimmunity in the development of articular bone disease in the context of chronic inflammatory disease.

Correlation between hand bone mineral density and joint destruction in established rheumatoid arthritis

OBJECTIVE

We aimed to clarify the correlation between bone mineral density (BMD) and the modified total Sharp score of the hand in Japanese patients with established rheumatoid arthritis (RA).

METHODS

We examined the hands of 57 patients who had RA for more than 20 years. BMD for the whole hand was measured using dual-energy x-ray absorptiometry. Concurrently, the hands were analyzed using radiography to estimate the van der Heijde-modified total Sharp score (vdH-S).

RESULTS

The patients were all women with a median age of 69.7 years and RA disease duration of 29.9 years. The correlation coefficients were -0.513 (P < 0.0001) for hand BMD and vdH-S of the hand, -0.576 (P < 0.0001) for hand BMD and the erosion score of the vdH-S, and -0.339 (P < 0.0001) for hand BMD and the joint narrowing score of the vdH-S.

CONCLUSIONS

Hand BMD is correlated with the vdH-S in long-established RA. The hand BMD is important for structural assessment of the hand. Additionally, we may be able to predict the vdH-S of the hand on the basis of the hand BMD in long-established RA.

Hand bone mass in rheumatoid arthritis: A review of the literature

Rheumatoid arthritis (RA) is a common chronic inflammatory disease and periarticular osteoporosis or osteopenia of the inflamed hand joints is an early feature of RA. Quantitative measurement of hand bone loss may be an outcome measure for the detection of joint destruction and disease progression in early RA. This systematic review examines the published literature reporting hand bone mass in patients with RA, particularly those using the dual X-ray absorptiometry (DXA) methods. The majority of the studies reported that hand bone loss is associated with disease activity, functional status and radiological progression in early RA. Quantitative measurement of hand bone mineral density by DXA may be a useful and practical outcome measure in RA and may be predictive for radiographic progression or functional status in patients with early RA.

Is hand bone mineral density a marker for hand function in patients with established rheumatoid arthritis? The correlation among bone mineral density of the hand, radiological findings and hand function

The objective of this study is to assess the role of hand bone mineral density (BMD) as a prospective marker for hand function and the correlation of hand BMD with X-ray findings and hand functioning in patients with established rheumatoid arthritis (RA). Eighty-three female patients diagnosed with RA were enrolled. All BMD measurements were performed on both hands. The radiological evaluation was conducted according to the van der Heijde modification of the Sharp method (Sharp/van der Heijde). Duruöz Hand Index (DHI) was used to establish the disability in the hands. Furthermore, handgrip strength (HGS), pinch strength (PS), lateral pinch (LP), tip-to-tip pinch (TTP) and three-fingered pinch (TFP) on both the dominant and the non-dominant hands was measured. A significant positive correlation between hand BMD and HGS as well as all PSs with p < 0.05 was observed, while no statistically significant relation was observed between BMD and DHI (p > 0.05). The hand BMD and the Sharp/van der Heijde scores were significantly in reverse correlation (p < 0.05). As for other DHI-related variants, HGS and PS and the total DHI scores were reversely correlated, while there was a positive significant association with radiological scores (p < 0.05). HGS and TTP were found significant (p < 0.05) as a result of a multivariant linear stepwise regression analysis among the sub-groups of DHI, HGS, LP, TTP, TFP and radiographic total scores. Our study demonstrated that a one-off hand BMD measurement failed to adequately indicate a loss in hand function as measured by DHI. Ultimately, HGS and TTP were shown to be the most effective indicators for measuring hand functions.

Periarticular bone gain at proximal interphalangeal joints and changes in bone turnover markers in response to tumor necrosis factor inhibitors in rheumatoid and psoriatic arthritis

OBJECTIVE

Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) are characterized by periarticular bone erosion; periarticular bone formation is a feature in PsA. The effect of anti-tumor necrosis factor-α (TNF-α) on periarticular bone remodeling is unclear in both diseases. Our aim was to assess the response of bone turnover markers (BTM) and hand bone mineral density (BMD) to anti-TNF over 3 years in RA and PsA.

METHODS

We measured serum bone-specific alkaline phosphatase (bone ALP), procollagen type-I N-propeptide (PINP), intact osteocalcin, C-terminal cross-linking telopeptides (CTX-I), urinary N-terminal cross-linking telopeptide of type-I collagen (NTX-I), and free deoxypyridinoline crosslinks (fDPD) at baseline, 1, 12, and 36 months. BMD measurements (hands/spine/hip) were obtained at 3 timepoints.

RESULTS

We recruited 62 patients (RA 35; PsA 27). BTM correlated significantly with hand BMD but not with central BMD. Low hand BMD was associated with RA and increased BTM. Following anti-TNF therapy, hip BMD declined while spine and hand BMD were unchanged. Periarticular BMD at proximal interphalangeal (PIP) joints increased while it decreased at metacarpophalangeal joints. Bone ALP increased steadily and was always higher in PsA. PINP and intact osteocalcin increased to a lesser extent, but resorption markers did not change.

CONCLUSION

At baseline, hand BMD was inversely associated with BTM. Bone formation rather than resorption markers better showed the bone response to anti-TNF. Despite a lack of effect on central BMD, the modest effect of anti-TNF on PIP BMD may provide evidence that BTM reflect specifically bone remodeling activity at periarticular sites of inflammation in RA and PsA.

Periarticular osteoporosis is a prominent feature in early rheumatoid arthritis: estimation using shaft to periarticular bone mineral density ratio

We aimed to quantify periarticular osteoporosis and investigate its significance in 45 patients with rheumatoid arthritis (RA) and 106 controls. Dual-energy X-ray absorptiometry (DXA) was used to determine the ratio of shaft to periarticular bone mineral density (BMD) as an index of periarticular demineralization. Periarticular osteoporosis was measured by conventional radiography. The BMDs of shaft and periarticular regions in eight designated areas on proximal phalanges were quantified. Clinical variables were examined to identify risk factors for periarticular osteoporosis. The assessment of periarticular osteoporosis on X-ray images reached a moderate degree of interobserver agreement among four physicians (ĸ = 0.47). For BMD quantification, we designed three types of mathematical formulae: the ratio of shaft to periarticular BMD, the mean of the ratios, and the ratio of the sums. These ratios were significantly higher in the patients with early RA (disease duration ≤ 3 yr) than in controls (P < 0.01). The findings were not as distinctive in patients with established RA. Body mass index, cumulative dose of corticosteroid, and C-terminal telopeptide were correlated with BMD ratios. Conclusively, DXA-assisted localized quantification and BMD ratio calculations are feasible for assessing periarticular demineralization. Periarticular osteoporosis is a relatively distinctive feature of early RA.

Relationship between early bone mineral density changes and long-term function and radiographic progression in rheumatoid arthritis

OBJECTIVE

To ascertain whether bone mineral density loss during the first year of treatment for early rheumatoid arthritis (RA) as assessed by dual x-ray absorptiometry (DXA) is associated with long-term function, quality of life, and radiographic progression.

METHODS

Early RA patients, prior to commencing disease-modifying antirheumatic drug therapy, underwent evaluation with DXA scans of both hands, femoral neck, and lumbar spine at the time of diagnosis, then at 1 year and final followup at >6 years. Clinical and laboratory data and hands and feet radiographs were obtained at baseline and final followup.

RESULTS

Sixty-four patients were assessed. At baseline, median disease duration was 6 months, mean 28-joint Disease Activity Score was 5.85, and median Health Assessment Questionnaire score was 1.38. Median followup was 6.4 years (range 5.1-7.2 years). For erosion scores, 86% of patients with hand bone density loss above the smallest detectable change after 1 year progressed versus 55% of those with no hand bone density loss (P = 0.006). However, baseline radiographs showed a similar strength of association. Eighty-four percent of patients with erosions at baseline had erosion progression versus 57% of those with no baseline erosions (P = 0.021). Additionally, first-year bone density loss was not associated with function and quality of life status at followup.

CONCLUSION

Hand bone loss during the first year of treatment in early RA, as assessed with DXA, was associated with a high likelihood of radiographic progression; however, in the current study this was not superior to baseline radiographs. Furthermore, it was not associated with patient-reported outcomes.

Systemic bone effects of biologic therapies in rheumatoid arthritis and ankylosing spondylitis

Inflammatory joint diseases are responsible of chronic systemic inflammation, joint degradations, deformities, and altered quality of life. Patients suffering from chronic rheumatic diseases also present increased bone fragility and increased fracture risk. Registration of biologic therapies has deeply modified care in rheumatic diseases, especially in rheumatoid arthritis and ankylosing spondylitis. The available biologics are the anti proinflammatory cytokine therapies (TNFα blockers, anakinra and tocilizumab) and the biologics active on T cell activation (abatacept and rituximab). These drugs succeeded in blocking disease activity and joint degradation. They are also able to stop systemic bone loss among patients with inflammatory rheumatic diseases. In this review, we present the current understanding of the inflammatory-induced bone loss and the skeletal effects of biologic therapies in inflammatory joint diseases.

Osteoporosis in inflammatory joint diseases

Rheumatoid arthritis (RA) and ankylosing spondylitis (AS) are two inflammatory joint diseases characterized by bone complications including osteoporosis. In RA, periarticular bone loss, bone erosions, and systemic osteoporosis are observed, with an increased risk of fractures. Determinants of fractures are underlying conditions (as RA has a female preponderance and an increased prevalence with age), severity of the disease, and use of glucocorticoids. However, bone loss can occur even in glucocorticoid-naive patients. Prospective data show that the optimal control of inflammation in RA is associated with decrease in structural damage and bone loss. RA illustrates the role of inflammation on bone resorption. In AS, osteoporosis is an early event and vertebral fracture risk is increased. Bone loss is related mainly to inflammation, as the disease can occur in young male adult populations, and glucocorticoids are not used in this disease. However, AS is characterized by progressive stiffness and ankylosis of the spine and illustrates also the potential role of inflammation on local bone formation.

Assessment of hand bone loss in rheumatoid arthritis by high-resolution peripheral quantitative CT

OBJECTIVES

A new high-resolution peripheral quantitative CT (HR-pQCT) system allows for in vivo assessment of bone microarchitecture and volumetric bone mineral density (vBMD) with an 82 microm isotropic resolution. With this device, the microarchitecture impairment was evaluated in patients with rheumatoid arthritis (RA) in comparison with healthy controls and measured the erosion volume at metacarpal heads (MCPs).

METHODS

In this cross-sectional study, the reproducibility was first assessed by 3 HR-pQCT exams with repositioning in 14 patients with late RA and 14 healthy subjects. Then, HR-pQCT parameters were measured in a group of 93 patients with RA and 31 healthy controls. Two RA subgroups were distinguished: early RA (disease duration < or =2 years) (n=36) and late RA (n=57) and compared them to healthy controls.

RESULTS

The precision of the HR-pQCT volumetric measurements as assessed with coefficient of variation ranged from 0.7% to 1.8% in patients with late RA and from 0.6% to 1.4% in healthy subjects at MCPs. Total and trabecular vBMD and trabecular thickness were significantly decreased in patients with RA compared to healthy subjects and were significantly correlated to disease activity. The erosion volume was highly correlated to a semiquantitative assessment using the Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT) scoring system applied to the HR-pQCT slices.

CONCLUSIONS

This study demonstrated the good reproducibility of the HR-pQCT volumetric measurements at MCPs and confirmed the involvement of trabecular compartment in periarticular osteopoenia. Thus, HR-pQCT appears interesting to simultaneously assess differences in bone volumetric density, microarchitecture and erosions.

Generalized bone loss as a predictor of three-year radiographic damage in African American patients with recent-onset rheumatoid arthritis

OBJECTIVE

To examine the association between baseline bone mineral density (BMD) and radiographic damage at 3 years of disease duration in a longitudinal cohort of African Americans with recent-onset rheumatoid arthritis (RA).

METHODS

African American RA patients with a disease duration of <2 years (n = 141) were included in the study. All patients underwent baseline BMD measurements (femoral neck and/or lumbar spine) using dual x-ray absorptiometry. T scores were calculated using normative data from the general population of African Americans. Patients were categorized as having osteopenia/osteoporosis (T score less than or equal to -1) or as being healthy. Hand and wrist radiographs, obtained at baseline and at 3 years of disease duration, were scored using the modified Sharp/van der Heijde method. The association between baseline BMD and total radiographic score at 3 years of disease was examined using multivariable negative binomial regression.

RESULTS

At baseline, the mean age and the mean disease duration were 52.4 years and 14.8 months, respectively; 85.1% of the patients were women. The average total radiographic scores at baseline and at 3 years of disease were 2.4 and 5.7, respectively. In the final reduced multivariable model, adjusting for age, sex, anti-cyclic citrullinated peptide antibody positivity, and the presence of radiographic damage at baseline, the total radiographic score at 3 years disease in patients with osteopenia/osteoporosis of the femoral neck was twice that in patients with normal bone density, and the difference was statistically significant (P = 0.0084). No association between lumbar spine osteopenia/osteoporosis and radiographic score was found.

CONCLUSION

Our findings suggest that reduced generalized BMD may be a predictor of future radiographic damage and support the hypothesis that radiographic damage and reduced generalized BMD in RA patients may share a common pathogenic mechanism.

[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.

A comparative review of the different techniques to assess hand bone damage in rheumatoid arthritis

Inflammatory related hand bone damage in rheumatoid arthritis is characterized by erosions and periarticular osteoporosis and can lead to substantial clinical disability. So far, conventional radiograph has been considered to be the gold standard for detecting bone damage and monitoring disease progression, but it lacks sensitivity. So other techniques have been recently developed to identify erosions earlier, to be able to change therapy; if necessary. This report reviews, in its first part, the different ways of detecting erosions such as conventional radiograph, magnetic resonance imaging or imaging ultrasonography and, in its second part, the techniques used for the assessment of hand periarticular osteoporosis like dual-X-ray absorptiometry, digital-X-ray radiogrammetry or quantitative ultrasonography.

Using hand bone mass measurements to assess progression of rheumatoid arthritis

In rheumatoid arthritis (RA) bone involvement presents as joint erosions in addition to generalized and periarticular osteoporosis. Joint erosions on radiographs of the hands and feet are considered to be the gold standard to evaluate progression of bone and joint damage in RA, even though erosions on radiographs are not used as a marker of early bone involvement. Periarticular bone loss seen on radiographs may be the first sign of bone involvement in RA. Over the last decade there has been an increased awareness of the importance of early aggressive treatment in RA, leading to a need for methods which can identify bone involvement in the early stages of RA. As inflammatory bone loss, especially at the hand, has been shown to occur early in RA, quantitative measures of hand bone loss have been proposed as an outcome measure for the detection of bone involvement. In this review article we present data supporting the hypothesis that both erosions and osteoporosis in RA occur as a result of the same pathophysiological mechanisms activating the osteoclast. Furthermore the role of hand bone loss as an early marker of inflammatory bone involvement, a predictor of subsequent radiographic joint damage and a response variable to anti-inflammatory treatment is discussed.

Aromatase inhibitor-induced arthralgia in early breast cancer: what do we know and how can we find out more?

Aromatase inhibitors (AIs) are a standard of care for the adjuvant treatment of hormone responsive early carcinoma of the breast as demonstrated in a number of large international phase III randomised trials. Arthralgia was a somewhat unexpected side effect of this class of agents and has proven to be potentially problematic in clinical practice. Although rates of up 35% have been reported in the randomised trials, the figure has been much higher in subsequent case series. There is concern that these symptoms are significant and may affect compliance and thus the overall efficacy of treatment. It is therefore extremely important that we evaluate this syndrome with a view to gaining more information regarding its clinical features and possible aetiological mechanism. The potential aetiological mechanisms and evidence for aromatase inhibitor-induced arthralgia (AIA) are reviewed in this article. Looking forward, it is now important that prospective clinical trials are well designed to evaluate this syndrome and potential therapeutic strategies to circumvent it. Radiological imaging and biochemical analyses may help our understanding of AIA and these are discussed.

Bone loss in patients with active early rheumatoid arthritis: infliximab and methotrexate compared with methotrexate treatment alone. Explorative analysis from a 12-month randomised, double-blind, placebo-controlled study

OBJECTIVE

To examine the effect of infliximab plus methotrexate (MTX) compared with placebo plus MTX on bone loss in patients with early rheumatoid arthritis (RA) in a double-blind randomised study design. Further, to explore the associations between bone loss and markers of RA disease.

METHODS

All 20 patients with RA (10 patients in each treatment group) had active, early RA. Bone mineral density (BMD) was assessed at the hand, lumbar spine (L2-4) and hip by dual energy x-ray absorptiometry at baseline and 12 months' follow-up. Clinical data were collected at regular visits.

RESULTS

BMD loss was significantly reduced in the infliximab group compared with the placebo group at the femoral neck (-0.35% vs -3.43%, p = 0.01) and total hip (-0.23% vs -2.62%, p = 0.03) but not at the hand (-2.09% vs -2.82%, p = 0.82) and spine (-0.75% vs -1.77%, p = 0.71). Measures of disease process and joint damage were found to be independently associated with bone loss.

CONCLUSIONS

This study provides strong evidence of a causal link between inflammation and bone loss in RA. The anti-inflammatory effect of infliximab was potent enough to arrest inflammatory bone loss at the hip but not at the spine and hand.

Antibodies to cyclic citrullinated protein and erythrocyte sedimentation rate predict hand bone loss in patients with rheumatoid arthritis of short duration: a longitudinal study

Introduction

Radiographic progression in rheumatoid arthritis (RA) has in several studies been shown to be predicted by serological markers widely used in daily clinical practice. The objective of this longitudinal study was to examine if these serological markers also predict hand bone mineral density (BMD) loss in patients with RA of short disease duration.

Methods

163 patients with RA of short disease duration (2.4 years) were included and followed longitudinally. Antibodies to cyclic citrullinated protein (anti-CCP), rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) were analysed from baseline blood-samples. Hand BMD was measured by digital X-ray radiogrammetry (DXR) based on hand and wrist radiographs obtained at baseline and 1, 2 and 5-year follow-up.

Results

During the study period, DXR-BMD decreased by median (inter quartile range) 1.7% (4.1 to 0.4), 2.8% (5.3 to 0.9) and 5.6% (11.7 to 2.3) after 1, 2 and 5 years, respectively. Elevated baseline anti-CCP, RF, ESR and CRP levels were in univariate linear regression analyses consistently associated with DXR-BMD change at all time-points. Anti-CCP and ESR were independently associated with hand DXR-BMD in multivariate linear regression analyses. Elevated anti-CCP levels were consistent and independent predictors of loss in cortical hand bone during the study period, with the odds ratios (95% confidence interval) 2.2 (1.0 to 4.5), 2.6 (1.1 to 6.2) and 4.9 (1.4 to 16.7) for the 1, 2, and 5-year follow-up periods, respectively.

Conclusions

Anti-CCP and ESR were found to be independent predictors of early localised BMD loss. This finding adds to the understanding of anti-CCP and ESR as important predictors of bone involvement in RA.

Adalimumab therapy reduces hand bone loss in early rheumatoid arthritis: explorative analyses from the PREMIER study

OBJECTIVE

The effect of adalimumab on hand osteoporosis was examined and related to radiographic joint damage in the three treatment arms of the PREMIER study: adalimumab plus methotrexate, adalimumab and methotrexate monotherapy. Predictors of hand bone loss were also searched for.

METHODS

768 patients (537 fulfilled 2 years) with rheumatoid arthritis (RA) for less than 3 years, never treated with methotrexate, were included. Hand bone loss was assessed by digital x ray radiogrammetry (DXR) on the same hand radiographs scored with modified Sharp score at baseline, 26, 52 and 104 weeks. For DXR, metacarpal cortical index (MCI) was the primary bone measure.

RESULTS

At all time points the rate of percentage DXR-MCI loss was lowest in the combination group (-1.15; -2.16; -3.03) and greatest in the methotrexate monotherapy group (-1.42; -2.87; -4.62), with figures in between for the adalimumab monotherapy group (-1.33; -2.45; -4.03). Significant differences between the combination group and the methotrexate group were seen at 52 (p = 0.009) and 104 weeks (p<0.001). The order of hand bone loss across the three treatment arms was similar to the order of radiographic progression. Older age, elevated C-reactive protein and non-use of adalimumab were predictors of hand bone loss.

CONCLUSION

This study supports a similar pathogenic mechanism for hand bone loss and erosions in RA. The combination of adalimumab and methotrexate seems to arrest hand bone loss less effectively than radiographic joint damage. Quantitative measures of osteoporosis may thus be a more sensitive tool for assessment of inflammatory bone involvement in RA.

Cortical hand bone loss after 1 year in early rheumatoid arthritis predicts radiographic hand joint damage at 5-year and 10-year follow-up

OBJECTIVE

To examine 1-year hand bone loss in early rheumatoid arthritis (RA) as a predictor of radiographic damage at 5-year and 10-year follow-up

METHODS

A total of 136 patients with RA (disease duration 0-4 years) were followed for 10 years with clinical data and hand radiographs. Joint damage was scored according to the van der Heijde modification of the Sharp method (vdH Sharp score) and hand bone mineral density (BMD) was measured by digital x ray radiogrammetry (DXR). Group comparisons, correlation analyses and multivariate analyses were performed to evaluate the relationship between hand bone loss and radiographic joint damage.

RESULTS

Patients with hand BMD loss at 1 year had a higher median increase in vdH Sharp score compared to patients without loss at 5 years (12 vs 2, p = 0.001) and 10 years (22 vs 4, p = 0.002). In a linear regression model adjusting for age, gender, baseline C-reactive protein (CRP), anti-cyclic citrullinated peptide (CCP), IgM rheumatoid factor (RF) and radiographic damage, absolute hand DXR-BMD loss at 1 year was an independent predictor of radiographic outcome at 5 years (p<0.01) and 10 years (p = 0.02). In a logistic regression model the odds ratio (95% CI) for radiographic progression among patients with hand BMD loss was 3.5 (1.4 to 8.8) and 3.5 (1.4 to 8.4) at 5 and 10 years, respectively.

CONCLUSION

Early hand bone loss measured by DXR-BMD is an independent predictor of subsequent radiographic damage. Our findings support that quantitative hand bone loss in RA precedes radiographic joint damage and may be used as a tool for assessment of bone involvement in RA.

Imaging of metabolic bone diseases

Bone scintigraphy and X-ray are complementary in the assessment of Paget's disease. Whereas bone scintigraphy allows visualization of the whole skeleton and 'hot spots', X-ray enables visualization of more detailed images of the pagetic bone lesion. X-ray may be invaluable in the diagnosis of osteomalacia, especially in children. As osteomalacia is characterized by impaired bone mineralization, the use of bone density measures may lead to misinterpretation of the condition as osteoporosis. Dual-energy X-ray absorptiometry at the femoral neck is the 'gold standard' for the assessment of osteoporosis. However, all devices are useful to predict the risk of fracture. In the future, high-resolution computer tomography and magnetic resonance imaging may become valuable clinical tools, capturing the architectural aspect of bone strength and improving fracture prediction models.

Short-time in vitro and in vivo precision of direct digital X-ray radiogrammetry

Digital X-ray radiogrammetry (DXR) calculates peripheral bone mineral density (BMD) from hand radiographs. The aim of this study was to examine in vitro and in vivo precision for the new direct digital version of DXR, a development of the conventional DXR. The in vitro precision for direct DXR was tested on 4 different X-ray equipment, based on 31 radiographs of the same phantom. The in vivo precision was based on duplicate hand radiographs from both hands in 39 individuals. For the 4 X-ray equipment, in vitro precision ranged from 0.14% to 0.30%, expressed as coefficient of variations (CV%) and from 0.0012 to 0.0028 g/cm2, expressed as smallest detectable difference (SDD). The precision was correlated to the resolution of the radiographic equipment (r=0.95, p=0.05). The corresponding values for the in vivo precision for mean values of both hands were: CV%=0.46%; SDD=0.0046 g/cm2, and least significant change (LSC%)=1.28%. The DXR-BMD for 1 of the X-ray equipment differed 1.1% from the overall mean. The precision for direct DXR was highly satisfactory both in vitro and in vivo. DXR-BMD values may differ between the radiographic equipment, and follow-up measurements should be performed with the same X-ray equipment.

Associations with subregional BMD-measurements in patients with rheumatoid arthritis

Patients with rheumatoid arthritis (RA) have bone loss to various degrees at different skeletal sites. The subregional bone mineral density (BMD) of the hand and the correlation of BMD to other regional bone losses, parameters of inflammation or bone resorption was evaluated in 421 patients with RA and controls. RA patients had significantly (P<0.01) lower BMD values in the carpus (0.405+/-0.004 g/cm2), metacarpal joint II (0.318+/-0.036 g/cm2) and metacarpal joint III (0.326+/-0.022 g/cm2) compared to controls. There was no difference in bone density at the lumbar spine or hip. Significant (P<0.001) correlations were found between BMD total of the hand, its subregions, the forearm and hip. Parameters of inflammation correlated significantly (P<0.001) with pyridinolines (r=0.378), desoxypyridinolines (r=0.183), forearm (r=-10, P<0.05), MCP II (r=-0.190, P<0.001), MCP III (r=0.204, P<0.001) and carpus (r=0.191, P<0.001).

Measurement of periarticular bone mineral density in the hands of patients with early inflammatory arthritis using dual energy x-ray absorptiometry

Hand bone densitometry is more sensitive than standard radiology in the measurement of disease-related bone damage in early arthritis. Most studies employing dual energy x-ray absorptiometry (DXA) have evaluated the whole hand. The aim of this study was to evaluate a method that quantified bone density in regions of interest that were confined to the juxta-articular areas of metacarpo-phalangeal (MCP) and proximal interphalangeal (PIP) joints. Patients with inflammatory arthritis affecting the hands were selected for study. Postero-anterior (PA) scans of selected juxta-articular sub-regions were acquired using a Hologic 4500 Elite bone densitometer and forearm software. Each hand was scanned three times in immediate succession with repositioning between scans. The six selected sub-regions included the periarticular regions of the second, third, and fourth MCP and PIP joints. Sub-regions of different dimensions (4 and 5 mm proximal and distal to the joint space) were assessed at each joint. Coefficients of variation (CV) were calculated for bone mineral density (BMD) and bone mineral content (BMC) of each selected sub-region. Eighty four individual hand joints in seven patients were evaluated three times. Precision values ranged between 0.89% and 2.37% for BMD and between 1.38 and 3.26 for BMC measurements. BMD measurements of MCP joints were more precise than PIP joints. BMD measurements of 10-mm sub-regions were more precise than 8-mm sub-regions. The precision value for the net average BMD measurement of the six sub-regions evaluated was 0.78% for 8-mm sub-regions and 0.73% for 10-mm sub-regions. Net average BMC measurements had CV values of 1.11% and 1.08%, respectively. DXA can be used to reliably measure periarticular BMD and BMC of small joints in the hands in patients with early inflammatory arthritis. Precision values for quantifying juxta-articular bone approximated BMD measurements of the spine.