Bone mineral apparent density in juvenile dermatomyositis: the role of lean body mass and glucocorticoid use

Body Composition and Phase Angle: How to Improve Nutritional Evaluation in Juvenile Dermatomyositis Patients

(1) Background: This study aimed to assess body composition (BC) using bioelectrical impedance and food intake in juvenile dermatomyositis (JDM) patients. Associations between BC and physical activity, disease activity/cumulative damage and health-related quality of life parameters were also evaluated; (2) Methods: This was a cross-sectional study with 30 consecutive JDM patients (18 female and 12 male) and 24 healthy volunteers (14 female and 10 male) of both sexes followed at our pediatric rheumatology unit. The gathering of anthropometric and dietary data, and the performance of physical activity and bioelectrical impedance were undertaken in face-to-face meetings and through questionnaires. Clinical and therapeutic data were collected from medical records according to information from routine medical appointments; (3) Results: The frequency of high/very high body fat was significantly higher in controls compared with JDM patients (66.7% vs. 91.7%; p = 0.046). The median phase angle was significantly lower in patients compared with controls (5.2 ± 1.3 vs. 6.1 ± 1.0; p = 0.016). Body fat and lean mass were positively correlated with disease duration (rs = +0.629, p < 0.001 and rs = +0.716, p < 0.001, respectively) and phase angle (PhA) (rs = +0.400, p = 0.029 and rs = +0.619, p < 0.001, respectively). JDM patients with PhA ≥ 5.5 presented higher lean mass when compared with patients with PhA < 5.5 (p = 0.001); (4) Conclusions: Bioelectrical impedance can be a useful auxiliary exam in the medical and nutritional follow-up of JDM patients, because it seems to impact functional ability. These findings may assist professionals when advising JDM patients about the importance of physical activity and healthy eating in the preservation of lean mass.

Patterns of body composition and alteration after treatment in patients with newly diagnosed idiopathic inflammatory myopathies

OBJECTIVES

To define the pattern of body composition and alteration after treatment of patients with newly diagnosed idiopathic inflammatory myopathies (IIMs) using DXA.

METHODS

DXA was used to obtain regional and whole-body measurements of fat mass and lean tissue mass (LTM) in 50 patients with newly diagnosed IIM and matched controls. The DXA indices of fat mass and LTM were calculated. The analyses included correlations between DXA indices and clinical parameters [manual muscle test (MMT), Myositis Damage Index (MDI), Myositis Intention-to-Treat Activities Index (MITAX), handgrip, percentage forced vital capacity (%FVC) and creatine kinase level], comparison between patients with IIM and controls, comparison between IIM subgroups, receiver operating characteristic (ROC) analysis, and comparison of body composition before and after treatment.

RESULTS

DXA LTM measurements were significantly correlated with MMT, MDI-muscle, handgrip strength, and %FVC. Patients with IIM had decreased LTM of the upper limbs and appendicular region. Male patients with IIM had significantly decreased LTM in the upper and lower limbs, whereas female patients with IIM had significantly decreased LTM in the upper limbs. Patients with IIM with anti-SRP seropositivity had lower LTM than patients with anti-SRP seronegativity. In ROC analysis, the DXA LTM indices presented good diagnostic values for distinguishing patients with newly diagnosed IIM from healthy controls. After treatment, the LTM of the upper limbs and appendicular region significantly increased.

CONCLUSION

DXA is an attractive method for the evaluation of patients with newly diagnosed IIM as well as a new way of monitoring disease conditions.

Bone Health in Children with Rheumatic Disorders: Focus on Molecular Mechanisms, Diagnosis, and Management

Bone is an extremely dynamic and adaptive tissue, whose metabolism and homeostasis is influenced by many different hormonal, mechanical, nutritional, immunological and pharmacological stimuli. Genetic factors significantly affect bone health, through their influence on bone cells function, cartilage quality, calcium and vitamin D homeostasis, sex hormone metabolism and pubertal timing. In addition, optimal nutrition and physical activity contribute to bone mass acquisition in the growing age. All these factors influence the attainment of peak bone mass, a critical determinant of bone health and fracture risk in adulthood. Secondary osteoporosis is an important issue of clinical care in children with acute and chronic diseases. Systemic autoimmune disorders, like juvenile idiopathic arthritis, can affect the skeletal system, causing reduced bone mineral density and high risk of fragility fractures during childhood. In these patients, multiple factors contribute to reduce bone strength, including systemic inflammation with elevated cytokines, reduced physical activity, malabsorption and nutritional deficiency, inadequate daily calcium and vitamin D intake, use of glucocorticoids, poor growth and pubertal delay. In juvenile arthritis, osteoporosis is more prominent at the femoral neck and radius compared to the lumbar spine. Nevertheless, vertebral fractures are an important, often asymptomatic manifestation, especially in glucocorticoid-treated patients. A standardized diagnostic approach to the musculoskeletal system, including prophylaxis, therapy and follow up, is therefore mandatory in at risk children. Here we discuss the molecular mechanisms involved in skeletal homeostasis and the influence of inflammation and chronic disease on bone metabolism.

Drug Treatment of Low Bone Mass and Other Bone Conditions in Pediatric Patients

Osteoporosis may affect young individuals, albeit infrequently. In childhood, bone mass increases, reaching its peak between the second and third decades; then, after a period of stability, it gradually declines. Several conditions, including genetic disorders, chronic diseases, and some medications, can have an impact on bone homeostasis. Diagnosis in young patients is based on the criteria defined by the International Society for Clinical Densitometry (ISCD), published in 2013. High risk factors should be identified and monitored. Often simple interventions aimed to eliminate the underlying cause, to minimize the negative bone effects linked to drugs, or to increase calcium and vitamin D intake can protect bone mass. However, in selected cases, pharmacological treatment should be considered. Bisphosphonates remain the main therapeutic agent for children with significant skeletal fragility and are also useful in a large number of other bone conditions. Denosumab, an anti-RANKL antibody, could become a potential alternative treatment. Clinical trials to evaluate the long-term effects and safety of denosumab in children are ongoing.

Body composition in longstanding juvenile dermatomyositis; Associations with disease activity, muscle strength and cardiometabolic measures

OBJECTIVE

To (i) compare body composition parameters in patients with longstanding juvenile dermatomyositis (JDM) and controls and (ii) explore associations between body composition and disease activity/inflammation, muscle strength, health-related quality of life (HRQL) and cardiometabolic measures.

METHODS

In a cross-sectional study, we included 59 patients (median disease duration 16.7 y; median age 21.5 y) and 59 age- and sex-matched controls. Active/inactive disease were defined by the PRINTO criteria. Body composition was assessed by total body dual-energy absorptiometry (DXA), inflammation by hs-CRP and cytokines, muscle strength by manual muscle test (MMT-8), HRQL by 36-item short form survey physical component score (SF-36 PCS) and cardiometabolic function by echocardiography (systolic and diastolic function) and serum-lipids.

RESULTS

DXA analyses revealed lower appendicular lean mass index (ALMI) (reflecting limb skeletal muscle mass), higher body fat percentage (BF%) and higher android: gynoid fat ratio (A: G ratio) (reflecting central fat distribution) in patients than controls, despite similar BMI. Patients with active disease had lower ALMI and higher BF% than those with inactive disease; lower ALMI and higher BF% were associated with inflammation (elevated monocyte attractant protein-1 (MCP-1) and hs-CRP). Lower ALMI was associated with reduced muscle strength; higher BF% was associated with impaired HRQL. Central fat distribution (higher A: G ratio) was associated with impaired cardiac function and unfavorable serum-lipids.

CONCLUSION

: Despite normal BMI, patients with JDM, especially those with active disease, had unfavorable body composition, which was associated with impaired HRQL/muscle strength and cardiometabolic function. The association between central fat distribution and cardiometabolic alterations is a novel finding in JDM.

A Literature Review of the Potential Impact of Medication on Vitamin D Status

In recent years, there has been a significant increase in media coverage of the putative actions of vitamin D as well as the possible health benefits that supplementation might deliver. However, the potential effect that medications may have on the vitamin D status is rarely taken into consideration. This literature review was undertaken to assess the degree to which vitamin D status may be affected by medication. Electronic databases were searched to identify literature relating to this subject, and study characteristics and conclusions were scrutinized for evidence of potential associations. The following groups of drugs were identified in one or more studies to affect vitamin D status in some way: anti-epileptics, laxatives, metformin, loop diuretics, angiotensin-converting enzyme inhibitors, thiazide diuretics, statins, calcium channel blockers, antagonists of vitamin K, platelet aggregation inhibitors, digoxin, potassium-sparing diuretics, benzodiazepines, antidepressants, proton pump inhibitors, histamine H2-receptor antagonists, bile acid sequestrants, corticosteroids, antimicrobials, sulphonamides and urea derivatives, lipase inhibitors, hydroxychloroquine, highly active antiretroviral agents, and certain chemotherapeutic agents. Given that the quality of the data is heterogeneous, newer, more robustly designed studies are required to better define likely interactions between vitamin D and medications. This is especially so for cytochrome P450 3A4 enzyme (CYP3A4)-metabolized medications. Nevertheless, this review suggests that providers of health care ought to be alert to the potential of vitamin D depletions induced by medications, especially in elderly people exposed to multiple-drug therapy, and to provide supplementation if required.

Bone mineral density and explanatory factors in children and adults with juvenile dermatomyositis at long term follow-up; a cross sectional study

BACKGROUND

Juvenile dermatomyositis (JDM) is the most common idiopathic inflammatory myopathy in children and adolescents. Both the disease and its treatment with glucocorticoids may negatively impact bone formation. In this study we compare BMD in patients (children/adolescence and adults) with long-standing JDM with matched controls; and in patients, explore how general/disease characteristics and bone turnover markers are associated with BMD.

METHODS

JDM patients (n = 59) were examined median 16.8y (range 6.6-27.0y) after disease onset and compared with 59 age/sex-matched controls. Dual-energy X-ray absorptiometry (DXA) was used to measure BMD of the whole body and lumbar spine (spine) in all participants, and of ultra-distal radius, forearm and total hip in participants ≥20y only. Markers of bone turnover were analysed, and associations with outcomes explored.

RESULTS

Reduced BMD Z-scores (<-1SD) were found in 19 and 29% of patients and 7 and 9% of controls in whole body and spine, respectively (p-values < 0.05). BMD and BMD Z-scores for whole body and spine were lower in all patients and for < 20y compared with their respective controls. In participants ≥20y, only BMD and BMD Z-score of forearm were lower in the patients versus controls. In patients, BMD Z-scores for whole body and/or spine were found to correlate negatively with prednisolone use at follow-up (yes/no) (age < 20y), inflammatory markers (age ≥ 20y) and levels of interferon gamma-induced protein 10 (IP-10) (both age groups). In all patients, prednisolone use at follow-up (yes/no) and age ≥ 20y were independent correlates of lower BMD Z-scores for whole body and spine, respectively.

CONCLUSION

In long-term JDM, children have more impairment of BMD than adults in spine and whole-body. Associations with BMD were found for both prednisolone and inflammatory markers, and a novel association was discovered with the biomarker of JDM activity, IP-10.

Bone health in idiopathic inflammatory myopathies

OBJECTIVE

To review the extant literature relating to bone health in the idiopathic inflammatory myopathies (IIM) including both adult and juvenile patients.

METHODS

A PubMed search® identified relevant studies from 1966 to 2020 in accordance with PRISMA guidelines. Two independent reviewers screened and extracted the abstracts/full manuscripts, and a third author was consulted in the case of disagreement.

RESULTS

We identified 37 articles (3 review articles, 2 RCTs, 9 cross-sectional, 16 cohort and 7 case-control studies). The prevalence of osteopenia (n = 7) ranges from 7 to 75% and osteoporosis (n = 7) between 13% to 27%. The prevalence of vertebral fractures ranged from 11 to 75%. Systemic inflammation likely contributes to reduced bone mineral density (BMD) in children with IIM but data is currently lacking in adult patients. Association between with impaired BMD and Vitamin D or calcium intake and physical activity has not been demonstrated in IIM. There is no clear consensus regarding the impact of age, menopause or BMI on bone health. Gender, smoking status, disease activity and inflammatory markers are not obvious independent predictors of low BMD. Several studies have demonstrated that glucocorticoids are associated with an increased risk of low BMD. There are no specific guidelines relating to the management of bone health in adult and juvenile patients with IIM.

CONCLUSION

Both adult and juvenile patients with IIM are at high risk of impaired bone health and fracture. The mechanisms behind this are likely multifactorial including systemic inflammation, glucocorticoid treatment, reduced mobility and impaired calcium/vitamin D homeostasis. There are a lack of guidelines and studies relating to the screening, prevention and treatment of impaired bone health in adult and juvenile patients with IIM. Future research is required to understand the complexity of bone health in IIM including to develop much needed disease-specific management recommendations.

Myostatin and markers of bone metabolism in dermatomyositis

Background

In dermatomyostis (DM) patients, inflammation, reduced activity, and medication have a negative impact on the musculoskeletal system. Several endocrine factors are involved in muscle growth and bone turnover.

Objective: We aimed to investigate factors regulating myogenesis and bone metabolism and to evaluate possible associations between these endocrine factors, muscle strength, and functional tests in DM patients.

Methods

We conducted a cross-sectional study in 20 dermatomyositis patients. Serum levels of myostatin (MSTN), follistatin (FSTN), dickkopf 1 (Dkk1), sclerostin (SOST), periostin (PSTN), the receptor activator nuclear factor kB ligand (RANKL):osteoprotegerin (OPG) ratio and fibroblast growth factor 23 (FGF23) were determined. Physical function was evaluated by hand-held strength measurement, chair rising test, timed up and go test and the 3-min walking test.

Results

Serum MSTN and FGF23 levels (2.5 [1.9; 3.2] vs. 1.9 [1.6; 2.3] and 2.17 [1.45; 3.26] vs. 1.28 [0.79; 1.96], respectively; p <  0.05) were significantly higher in DM patients than in controls. Dkk1 was significantly lower (11.4 [6.9; 20.0] vs. 31.8 [14.3; 50.6], p <  0.01). Muscle strength and physical function tests correlated with each other (e.g. hip flexion – timed up and go test: r = − 0.748, p < 0.01).

Conclusion

In DM patients, biochemical musculo-skeletal markers are altered and physical function shows deficits. All these tests reflect independent of each other different deficits in long-term DM patients which is important for the assessment of DM patients as well as planning of therapeutic interventions in clinical routine.

The risk of fracture and prevalence of osteoporosis is elevated in patients with idiopathic inflammatory myopathies: cross-sectional study from a single Hungarian center

BACKGROUND

The prevalence of osteoporosis and risk of fractures is elevated in rheumatoid arthritis (RA), but we have limited information about the bone mineral density (BMD) and fracture risk in patients with inflammatory myopathies. We intended to ascertain and compare fracture risk, bone mineral density and the prevalence of vertebral fractures in patients with inflammatory myositis and rheumatoid arthritis and to assess the effect of prevalent fractures on the quality of life and functional capacity.

METHODS

Fifty-two patients with myositis and 43 patients with rheumatoid arthritis were included in the study. Fracture Risk was determined using FRAX® Calculation Tool developed by the University of Sheffield. Dual energy X-ray absorptiometry and bidirectional thoracolumbar radiographs were performed to assess BMD and vertebral fractures. Quality of life was measured with Short Form-36 (SF-36) and physical function assessment was performed using Health Assessment Questionnaire (HAQ).

RESULTS

We found a significantly elevated fracture risk in RA as compared to myositis patients if the risk assessment was performed without the inclusion of the BMD results. If BMD results and glucocorticoid dose adjustment were taken into account, the differences in fracture risk were no longer significant. The prevalence of osteoporosis was found to be significantly higher in the myositis group (7% vs. 13.5%, p: 0.045), but the fracture prevalence was similar in the two groups (75% vs. 68%). The fracture rates were independently associated with age in the myositis group, and with lower BMD results in the RA patients. The number of prevalent fractures was significantly correlated to poorer physical function in both groups, and poorer health status in the myositis group, but not in the RA group.

CONCLUSIONS

Our findings suggest that inflammatory myopathies carry significantly elevated risks for osteoporosis and fractures. These higher risks are comparable to ones detected with RA in studies and strongly affect the physical function and quality of life of patients. Therefore further efforts are required to make the fracture risk assessment reliable and to facilitate the use of early preventive treatments.

Glucocorticoid-Induced Osteoporosis: Why Kids Are Different

Glucocorticoids (GC) are an important risk factor for bone fragility in children with serious illnesses, largely due to their direct adverse effects on skeletal metabolism. To better appreciate the natural history of fractures in this setting, over a decade ago the Canadian STeroid-associated Osteoporosis in the Pediatric Population ("STOPP") Consortium launched a 6 year, multi-center observational cohort study in GC-treated children. This study unveiled numerous key clinical-biological principles about GC-induced osteoporosis (GIO), many of which are unique to the growing skeleton. This was important, because most GIO recommendations to date have been guided by adult studies, and therefore do not acknowledge the pediatric-specific principles that inform monitoring, diagnosis and treatment strategies in the young. Some of the most informative observations from the STOPP study were that vertebral fractures are the hallmark of pediatric GIO, they occur early in the GC treatment course, and they are frequently asymptomatic (thereby undetected in the absence of routine monitoring). At the same time, some children have the unique, growth-mediated ability to restore normal vertebral body dimensions following vertebral fractures. This is an important index of recovery, since spontaneous vertebral body reshaping may preclude the need for osteoporosis therapy. Furthermore, we now better understand that children with poor growth, older children with less residual growth potential, and children with ongoing bone health threats have less potential for vertebral body reshaping following spine fractures, which can result in permanent vertebral deformity if treatment is not initiated in a timely fashion. Therefore, pediatric GIO management is now predicated upon early identification of vertebral fractures in those at risk, and timely intervention when there is limited potential for spontaneous recovery. A single, low-trauma long bone fracture can also signal an osteoporotic event, and a need for treatment. Intravenous bisphosphonates are currently the recommended therapy for pediatric GC-induced bone fragility, typically prescribed to children with limited potential for medication-unassisted recovery. It is recognized, however, that even early identification of bone fragility, combined with timely introduction of intravenous bisphosphonate therapy, may not completely rescue the osteoporosis in those with the most aggressive forms, opening the door to novel strategies.

Galectin-9 and CXCL10 as Biomarkers for Disease Activity in Juvenile Dermatomyositis: A Longitudinal Cohort Study and Multicohort Validation

Objective

Objective evaluation of disease activity is challenging in patients with juvenile dermatomyositis (DM) due to a lack of reliable biomarkers, but it is crucial to avoid both under‐ and overtreatment of patients. Recently, we identified 2 proteins, galectin‐9 and CXCL10, whose levels are highly correlated with the extent of juvenile DM disease activity. This study was undertaken to validate galectin‐9 and CXCL10 as biomarkers for disease activity in juvenile DM, and to assess their disease specificity and potency in predicting the occurrence of flares.

Methods

Levels of galectin‐9 and CXCL10 were measured by multiplex immunoassay in serum samples from 125 unique patients with juvenile DM in 3 international cross‐sectional cohorts and a local longitudinal cohort. The disease specificity of both proteins was examined in 50 adult patients with DM or nonspecific myositis (NSM) and 61 patients with other systemic autoimmune diseases.

Results

Both cross‐sectionally and longitudinally, galectin‐9 and CXCL10 outperformed the currently used laboratory marker, creatine kinase (CK), in distinguishing between juvenile DM patients with active disease and those in remission (area under the receiver operating characteristic curve [AUC] 0.86–0.90 for galectin‐9 and CXCL10; AUC 0.66–0.68 for CK). The sensitivity and specificity for active disease in juvenile DM was 0.84 and 0.92, respectively, for galectin‐9 and 0.87 and 1.00, respectively, for CXCL10. In 10 patients with juvenile DM who experienced a flare and were prospectively followed up, continuously elevated or rising biomarker levels suggested an imminent flare up to several months before the onset of symptoms, even in the absence of elevated CK levels. Galectin‐9 and CXCL10 distinguished between active disease and remission in adult patients with DM or NSM (P = 0.0126 for galectin‐9 and P < 0.0001 for CXCL10) and were suited for measurement in minimally invasive dried blood spots (healthy controls versus juvenile DM, P = 0.0040 for galectin‐9 and P < 0.0001 for CXCL10).

Conclusion

In this study, galectin‐9 and CXCL10 were validated as sensitive and reliable biomarkers for disease activity in juvenile DM. Implementation of these biomarkers into clinical practice as tools to monitor disease activity and guide treatment might facilitate personalized treatment strategies.

Protecting Bone Health in Pediatric Rheumatic Diseases: Pharmacological Considerations

Bone health in children with rheumatic conditions may be compromised due to several factors related to the inflammatory disease state, delayed puberty, altered life style, including decreased physical activities, sun avoidance, suboptimal calcium and vitamin D intake, and medical treatments, mainly glucocorticoids and possibly some disease-modifying anti-rheumatic drugs. Low bone density or even fragility fractures could be asymptomatic; therefore, children with diseases of high inflammatory load, such as systemic onset juvenile idiopathic arthritis, juvenile dermatomyositis, systemic lupus erythematosus, and those requiring chronic glucocorticoids may benefit from routine screening of bone health. Most commonly used assessment tools are laboratory testing including serum 25-OH-vitamin D measurement and bone mineral density measurement by a variety of methods, dual-energy X-ray absorptiometry as the most widely used. Early disease control, use of steroid-sparing medications such as disease-modifying anti-rheumatic drugs and biologics, supplemental vitamin D and calcium, and promotion of weight-bearing physical activities can help optimize bone health. Additional treatment options for osteoporosis such as bisphosphonates are still controversial in children with chronic rheumatic diseases, especially those with decreased bone density without fragility fractures. This article reviews common risk factors leading to compromised bone health in children with chronic rheumatic diseases and discusses the general approach to prevention and treatment of bone fragility.

Bone impairment assessed by HR-pQCT in juvenile-onset systemic lupus erythematosus

High-resolution peripheral quantitative computed tomography (HR-pQCT) analysis of female juvenile-onset systemic lupus erythematosus (JoSLE) patients revealed trabecular/cortical bone damage and reduced bone strength primarily at the distal radius compared to healthy controls. We demonstrated for the first time that JoSLE patients with vertebral fracture (VF) present trabecular impairment at the distal radius.

INTRODUCTION

This study investigated the volumetric bone mineral density (vBMD), microarchitecture, and biomechanical features at the distal radius and tibia using HR-pQCT and laboratory bone markers in JoSLE patients compared to controls to determine whether this method discriminates JoSLE patients with or without VF.

METHODS

We compared 56 female JoSLE patients to age- and Tanner-matched healthy controls. HR-pQCT was performed at the distal radius and tibia. Serum levels of the amino-terminal pro-peptide of type I collagen, the C-terminal telopeptide of type I collagen, intact parathormone, sclerostin, and 25-hydroxyvitamin D (25OHD) were evaluated. VFs were analyzed using VFA-dual-energy X-ray absorptiometry (DXA) (Genant's method).

RESULTS

Reduced density and strength parameters and microarchitecture alterations of cortical and trabecular bones were observed in JoSLE patients compared to controls, primarily at the distal radius (p < 0.05). Patients with VF exhibited a significant decrease in trabecular bone parameters solely at the distal radius (Total.BMD, p = 0.034; Trabecular.BMD [Tb.BMD], p = 0.034; bone volume (BV)/trabecular volume (TV), p = 0.034; apparent modulus, p = 0.039) and higher scores for disease damage (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SLICC/ACR-DI), p = 0.002). Bone metabolism markers were similar in all groups. Logistic regression analysis of parameters that were significant in univariate analysis revealed that Tb.BMD (OR 0.98, 95 % CI 0.95-0.99, p = 0.039) and SLICC/ACR-DI (OR 7.37, 95 % CI 1.75-30.97, p = 0.006) were independent risk factors for VF.

CONCLUSION

In conclusion, this study is the first demonstration of bone microstructure and strength deficits in JoSLE patients, particularly at the distal radius. Our results demonstrated that VF was associated with trabecular radius alteration and emphasized the potential detrimental effect of disease damage on this condition.

Increased osteoporosis risk in dermatomyositis or polymyositis independent of the treatments: a population-based cohort study with propensity score

We investigated the relationship between dermatomyositis/polymyositis (DM/PM) and the risk of subsequent osteoporosis development. A population-based retrospective cohort analysis was conducted using the National Health Insurance Research Database and the Catastrophic Illness Patients Database of Taiwan. We included 1179 patients and 4716 patients from 1999 to 2008 as the DM/PM cohort and the comparison cohort, respectively, and calculated the incidence rates of newly diagnosed osteoporosis. We used Cox proportional hazards models stratified on matched pair to assess the effect of DM/PM. The Kaplan-Meier method was applied to estimate the cumulative osteoporosis incidence curves. Patients with DM/PM were 2.99 times more likely to experience osteoporosis than those without DM/PM. The risk for osteoporosis in DM/PM patients was higher than comparisons in different propensity score quartiles. DM/PM cohort, no matter treated with or without corticosteroids and immunosuppressant, had a higher risk than the comparison cohort. The incidence of osteoporosis in Taiwan is associated with a priori DM/PM history. This risk was independent of the corticosteroids and immunosuppressant treatment.

The impact of underlying disease on fracture risk and bone mineral density in children with rheumatic disorders: A review of current literature

Childhood rheumatic diseases are associated with negative impacts on the skeleton, related to both the underlying illness and complications of therapy. The effects of medications like corticosteroids are well recognized, leading to reductions in bone mineral density and bone strength and concomitant increases in bone fragility and fracture risk. The impact of factors directly attributable to the underlying disease is not as well recognized. In this article, we review relevant literature to identify data which can contribute to an understanding of the impact of childhood rheumatic disease on the skeleton. We conclude that childhood rheumatic diseases are associated with reductions in bone mineral density and increased risk of vertebral and non-vertebral fractures. These data are strongest for juvenile arthritis, while conclusions are more limited for other rheumatic illnesses, like juvenile systemic lupus erythematosus or juvenile dermatomyositis, due to small numbers of patients studied. Finally, we make recommendations for areas in need of further research. These include the need for long-term longitudinal studies and for data to be collected in patients who have not been treated with corticosteroids.

Multiscale modelling of relationships between protein classes and drug behavior across all diseases using the CANDO platform

We have examined the effect of eight different protein classes (channels, GPCRs, kinases, ligases, nuclear receptors, proteases, phosphatases, transporters) on the benchmarking performance of the CANDO drug discovery and repurposing platform (http://protinfo.org/cando). The first version of the CANDO platform utilizes a matrix of predicted interactions between 48278 proteins and 3733 human ingestible compounds (including FDA approved drugs and supplements) that map to 2030 indications/diseases using a hierarchical chem and bio-informatic fragment based docking with dynamics protocol (> one billion predicted interactions considered). The platform uses similarity of compound-proteome interaction signatures as indicative of similar functional behavior and benchmarking accuracy is calculated across 1439 indications/diseases with more than one approved drug. The CANDO platform yields a significant correlation (0.99, p-value < 0.0001) between the number of proteins considered and benchmarking accuracy obtained indicating the importance of multitargeting for drug discovery. Average benchmarking accuracies range from 6.2 % to 7.6 % for the eight classes when the top 10 ranked compounds are considered, in contrast to a range of 5.5 % to 11.7 % obtained for the comparison/control sets consisting of 10, 100, 1000, and 10000 single best performing proteins. These results are generally two orders of magnitude better than the average accuracy of 0.2% obtained when randomly generated (fully scrambled) matrices are used. Different indications perform well when different classes are used but the best accuracies (up to 11.7% for the top 10 ranked compounds) are achieved when a combination of classes are used containing the broadest distribution of protein folds. Our results illustrate the utility of the CANDO approach and the consideration of different protein classes for devising indication specific protocols for drug repurposing as well as drug discovery.

Osteoporosis in rheumatic diseases

Rheumatic diseases, characterized by chronic inflammation and damage to various organs and systems, include systemic lupus erythematosus, rheumatoid arthritis, ankylosing spondylitis and other connective tissue diseases. Bone is a target in many inflammatory rheumatic diseases. In recent years, the survival of patients with rheumatic diseases has increased markedly and the relationship between rheumatic diseases and osteoporosis (OP) has become more prominent. OP and related fragility fractures increase the morbidity and mortality of rheumatic disease. The cause of OP in rheumatic diseases is complex. The pathogenesis of OP in rheumatic diseases is multifactorial, including disease and treatment-related factors. Osteoimmunology, a crosstalk between inflammatory and bone cells, provides some insight into the pathogenesis of bone loss in systematic inflammatory diseases. The aim of this article is to review different risk factors in rheumatic diseases. Several factors play a role, such as chronic inflammation, immunological factors, traditional factors, metabolism and drug factors. Chronic inflammation is the most important risk factor and drug treatment is complex in patients with OP and rheumatic disease. Attention should be paid to bone loss in rheumatic disease. Optimal treatment of the underlying rheumatic disease is the first step towards prevention of OP and fractures. Apart from that, a healthy lifestyle is important as well as calcium and vitamin D supplementation. Bisphosphonates or denosumab might be necessary for patients with a low T score.

Efficacy and safety of creatine supplementation in childhood-onset systemic lupus erythematosus: a randomized, double-blind, placebo-controlled, crossover trial

Introduction

Creatine supplementation has emerged as a promising non-pharmacological therapeutic strategy to counteract muscle dysfunction and low lean mass in a variety of conditions, including in pediatric and rheumatic diseases. The objective of this study was to examine the efficacy and safety of creatine supplementation in childhood systemic lupus erythematosus (C-SLE).

Methods

C-SLE patients with mild disease activity ( n = 15) received placebo or creatine supplementation in a randomized fashion using a crossover, double-blind, repeated-measures design. The participants were assessed at baseline and after 12 weeks in each arm, interspersed by an eight-week washout period. The primary outcomes were muscle function, as assessed by a battery of tests including one-maximum repetition (1-RM) tests, the timed-up-and-go test, the timed-stands test, and the handgrip test. Secondary outcomes included body composition, biochemical markers of bone remodeling, aerobic conditioning, quality of life, and physical capacity. Possible differences in dietary intake were assessed by three 24-hour dietary recalls. Muscle phosphorylcreatine content was measured through phosphorus magnetic resonance spectroscopy (31 P-MRS). The safety of the intervention was assessed by laboratory parameters, and kidney function was measured by 51Cr-EDTA clearance. Additionally, self-reported adverse events were recorded throughout the trial.

Results

Intramuscular phosphorylcreatine content was not significantly different between creatine and placebo before or after the intervention (creatine-Pre: 20.5 ± 2.6, Post: 20.4 ± 4.1, placebo-Pre: 19.8 ± 2.0; Post: 20.2 ± 3.2 mmol/kg wet muscle; p = 0.70 for interaction between conditions). In addition, probably as a consequence of the lack of change in intramuscular phosphorylcreatine content, there were no significant changes between placebo and creatine for any muscle function and aerobic conditioning parameters, lean mass, fat mass, bone mass, and quality of life scores ( p > 0.05). The 51Cr-EDTA clearance was not altered by creatine supplementation and no side effects were noticed.

Conclusion

A 12-week creatine supplementation protocol at 0.1 g/kg/d is well tolerated and free of adverse effects but did not affect intramuscular phosphorylcreatine, muscle function, free-fat mass or quality of life in non-active C-SLE patients.

Trial registration

Clinicaltrials.gov number: NCT01217320.

Glucocorticoid-associated osteoporosis in chronic inflammatory diseases: epidemiology, mechanisms, diagnosis, and treatment

Children with chronic illnesses such as Juvenile Idiopathic Arthritis and Crohn's disease, particularly when taking glucocorticoids, are at significant risk for bone fragility. Furthermore, when childhood illness interferes with achieving normal peak bone mass, life-long fracture risk is increased. Osteopenia and osteoporosis, which is increasingly recognized in pediatric chronic disease, likely results from numerous disease- and treatment-related factors, including glucocorticoid exposure. Diagnosing osteoporosis in childhood is complicated by the limitations of current noninvasive techniques such as DXA, which despite its limitations remains the gold standard. The risk:benefit ratio of treatment is confounded by the potential for spontaneous restitution of bone mass deficits and reshaping of previously fractured vertebral bodies. Bisphosphonates have been used to treat secondary osteoporosis in children, but limited experience and potential long-term toxicity warrant caution in routine use. This article reviews the factors that influence loss of normal bone strength and evidence for effective treatments, in particular in patients with gastrointestinal and rheumatologic disorders who are receiving chronic glucocorticoid therapy.

Bone mineral density, vitamin D, and nutritional status of children submitted to hematopoietic stem cell transplantation

OBJECTIVE

The aim of the study was to evaluate the effect of allogeneic hematopoietic stem cell transplantation (HSCT) on bone mineral density (BMD), serum vitamin D levels, and nutritional status of 50 patients between ages 4 and 20 y.

METHODS

We conducted pre-HSCT and 6-mo post-HSCT evaluations. We measured BMD at the lumbar spine (LS) and total body (TB) by dual energy x-ray absorptiometry (DXA); body composition by bioimpedance analysis, and dietary intakes of calcium and vitamin D using the 24-h recall and semiquantitative food frequency questionnaire methods.

RESULTS

We observed a significant reduction in BMD 6 mo post-HSCT. Nearly half (48%) of patients had reductions at the LS (average -9.6% ± 6.0%), and patients who developed graft-versus-host disease (GVHD) had the greatest reductions (-5.6% versus 1.2%, P < 0.01). We also found reductions in serum levels of 25-hydroxyvitamin D (25-OHD), from 25.6 ± 10.9 ng/dL to 20.4 ± 11.4 ng/dL (P < 0.05), and in body weight. Corticosteroid treatment duration, severity of chronic GVHD, serum 25-OHD levels, and family history of osteoporosis were all risk factors associated with variations in BMD at the LS.

CONCLUSION

HSCT in children and adolescents negatively effects their BMD, nutritional status, and vitamin D levels. We suggest that early routine assessment be done to permit prevention and treatment.

Drug-vitamin D interactions: a systematic review of the literature

Extensive media coverage of the potential health benefits of vitamin D supplementation has translated into substantial increases in supplement sales over recent years. Yet, the potential for drug-vitamin D interactions is rarely considered. This systematic review of the literature was conducted to evaluate the extent to which drugs affect vitamin D status or supplementation alters drug effectiveness or toxicity in humans. Electronic databases were used to identify eligible peer-reviewed studies published through September 1, 2010. Study characteristics and findings were abstracted, and quality was assessed for each study. A total of 109 unique reports met the inclusion criteria. The majority of eligible studies were classified as class C (nonrandomized trials, case-control studies, or time series) or D (cross-sectional, trend, case report/series, or before-and-after studies). Only 2 class C and 3 class D studies were of positive quality. Insufficient evidence was available to determine whether lipase inhibitors, antimicrobial agents, antiepileptic drugs, highly active antiretroviral agents, or H2 receptor antagonists alter serum 25(OH)D concentrations. Atorvastatin appears to increase 25(OH)D concentrations, whereas concurrent vitamin D supplementation decreases concentrations of atorvastatin. Use of thiazide diuretics in combination with calcium and vitamin D supplements may cause hypercalcemia in the elderly or those with compromised renal function or hyperparathyroidism. Larger studies with stronger study designs are needed to clarify potential drug-vitamin D interactions, especially for drugs metabolized by cytochrome P450 3A4 (CYP3A4). Healthcare providers should be aware of the potential for drug-vitamin D interactions.

Juvenile dermatomyositis

Juvenile dermatomyositis (JDM) is a systemic, inflammatory, idiopathic disease, mainly affecting the skin and the muscles, starting before the age of 16, with an incidence around one case per 1 million children. Some patients display typical features of JDM without skin involvement, or even without muscle involvement; however, both tissues are affected over time in most cases. Diagnosis criteria were established by Bohan and Peter 35 years ago, based on the presence of typical skin rash and proximal muscle involvement. Other conditions have to be ruled out before making a diagnosis of JDM, such as other connective tissue diseases, polymyositis, infectious/postinfectious myositis, genetic diseases, or metabolic or drug-induced myopathies. Unlike adult-onset dermatomyositis, JDM is exceptionally associated with a malignant disease. JDM may also affect several organs, including the lungs and the digestive tract. In a subset of patients, glucose intolerance, lipodystrophia and/or calcinosis develop. Delay in treatment initiation or inadequate treatment may favor diffuse, debilitating calcinosis. JDM patients have to be referred to reference pediatric centers to properly assess disease activity and disease-related damage (including low bone density in most cases), and to define the best treatment. Long-lasting corticosteroid therapy remains the gold standard, together with physiotherapy. Ongoing clinical trials are assessing the effect of several immunosuppressive and immunomodulatory drugs, which may help to control the disease and possibly demonstrate a corticosteroid-sparing effect. Most patients respond to treatment; relapses are frequent but a complete disease remission is achieved in most cases before adulthood.

High frequency of osteoporosis and fractures in women with dermatomyositis/polymyositis

Bone mass was only previously studied in juvenile dermatomyositis/polymyositis (DM/PM) patients. Therefore, the objective this study was to evaluate the prevalence of osteoporosis and fractures in adult DM/PM. Forty female DM/PM and 78 age-, gender-, and BMI-matched healthy controls were studied. Medical charts and clinical interviews of all patients were evaluated for demographic and clinical data, including disease activity, cumulative doses of glucocorticoid, menarche and menopause age, and fractures. Bone mineral density (BMD) using dual X-ray absorptiometry (DXA) were measured at lumbar spine (L1-L4) and hip. A decreased BMD in lumbar spine [0.902 (0.136) vs. 0.965 (0.141) g/cm(2), P = 0.022] and femoral neck [0.729 (0.12) vs. 0.784 (0.127) g/cm(2), P = 0.027] was observed in patients compared to controls. In addition, osteoporosis was more frequent in patients than in controls in both lumbar spine (20 vs. 3.8%, P = 0.007) and the femoral neck (27.5 vs. 10.3%, P = 0.016). Moreover, a high prevalence of fractures was found in patients in comparison to healthy subjects (17.9 vs. 5.1%, P = 0.040; OR = 3.92; CI 95%:1.07-14.33). Comparing DM/PM patients with (n = 17) and without (n = 23) osteoporosis/fractures, significant differences were observed regarding age [56.8 (11.9) vs. 48.3 (13.2) years, P = 0.042], weight [62.05 (13.56) vs. 71.51 (11.46) kg, P = 0.022] and frequency of post menopausal women (94.1 vs. 65.2%, P = 0.0002). No differences were observed concerning height, lean mass, total fat mass, disease activity, mean value of creatine kinase, cumulative glucocorticoid dose, or bisphosphonate use. Logistic regression analysis revealed a negative association between the presence of osteoporosis/fractures and weight (OR: 0.92, 95% CI: 0.85-0.98; P = 0.016). This is the first study that analyzed bone mass in adult DM/PM patients and it demonstrated that about one quarter of these patients have osteoporosis/fracture.

Responsiveness to exercise training in juvenile dermatomyositis: a twin case study

BACKGROUND

Patients with juvenile dermatomyositis (JDM) often present strong exercise intolerance and muscle weakness. However, the role of exercise training in this disease has not been investigated.

PURPOSE

this longitudinal case study reports on the effects of exercise training on a 7-year-old patient with JDM and on her unaffected monozygotic twin sister, who served as a control.

METHODS

Both the patient who was diagnosed with JDM as well as her healthy twin underwent a 16-week exercise training program comprising aerobic and strengthening exercises. We assessed one repetition-maximum (1-RM) leg-press and bench-press strength, balance, mobility and muscle function, blood markers of inflammation and muscle enzymes, aerobic conditioning, and disease activity scores. As a result, the healthy child had an overall greater absolute strength, muscle function and aerobic conditioning compared to her JDM twin pair at baseline and after the trial. However, the twins presented comparable relative improvements in 1-RM bench press, 1-RM leg press, VO2peak, and time-to-exhaustion. The healthy child had greater relative increments in low-back strength and handgrip, whereas the child with JDM presented a higher relative increase in ventilatory anaerobic threshold parameters and functional tests. Quality of life, inflammation, muscle damage and disease activity scores remained unchanged.

RESULTS AND CONCLUSION

this was the first report to describe the training response of a patient with non-active JDM following an exercise training regimen. The child with JDM exhibited improved strength, muscle function and aerobic conditioning without presenting an exacerbation of the disease.

Prevalent vertebral fractures among children initiating glucocorticoid therapy for the treatment of rheumatic disorders

OBJECTIVE

Vertebral fractures are an under-recognized problem in children with inflammatory disorders. We studied spine health among 134 children (87 girls) with rheumatic conditions (median age 10 years) within 30 days of initiating glucocorticoid therapy.

METHODS

Children were categorized as follows: juvenile dermatomyositis (n = 30), juvenile idiopathic arthritis (n = 28), systemic lupus erythematosus and related conditions (n = 26), systemic arthritis (n = 22), systemic vasculitis (n = 16), and other conditions (n = 12). Thoracolumbar spine radiograph and dual x-ray absorptiometry for lumbar spine (L-spine) areal bone mineral density (BMD) were performed within 30 days of glucocorticoid initiation. Genant semiquantitative grading was used for vertebral morphometry. Second metacarpal morphometry was carried out on a hand radiograph. Clinical factors including disease and physical activity, calcium and vitamin D intake, cumulative glucocorticoid dose, underlying diagnosis, L-spine BMD Z score, and back pain were analyzed for association with vertebral fracture.

RESULTS

Thirteen vertebral fractures were noted in 9 children (7%). Of these, 6 patients had a single vertebral fracture and 3 had 2-3 fractures. Fractures were clustered in the mid-thoracic region (69%). Three vertebral fractures (23%) were moderate (grade 2); the others were mild (grade 1). For the entire cohort, mean +/- SD L-spine BMD Z score was significantly different from zero (-0.55 +/- 1.2, P < 0.001) despite a mean height Z score that was similar to the healthy average (0.02 +/- 1.0, P = 0.825). Back pain was highly associated with increased odds for fracture (odds ratio 10.6 [95% confidence interval 2.1-53.8], P = 0.004).

CONCLUSION

In pediatric rheumatic conditions, vertebral fractures can be present prior to prolonged glucocorticoid exposure.

Juvenile-onset clinically amyopathic dermatomyositis: an overview of recent progress in diagnosis and management

Juvenile-onset amyopathic dermatomyositis is an uncommon variant of juvenile-onset dermatomyositis (JDM), characterized by the hallmark cutaneous features of dermatomyositis for at least 6 months without clinical or laboratory evidence of muscle disease. Cutaneous calcinosis, vasculopathy, and interstitial lung disease frequently complicate the course of classic JDM (typical JDM with myositis) but are infrequent in amyopathic JDM. Recent literature suggests that approximately 75% of amyopathic JDM patients will remain free from muscle disease after years of follow-up, while approximately 25% of patients will evolve to having classic JDM. No clinical, laboratory, or ancillary parameters have been found to be predictive for this transition to muscle disease. Treatment of the cutaneous disease of amyopathic JDM centers on photoprotection and topical therapies directed against inflammation. Oral antimalarials are effective for cutaneous disease not adequately controlled with topical care. Systemic corticosteroids, while central to the treatment of classic JDM, are controversial in the treatment of amyopathic JDM. Randomized controlled trials are not available to guide the management of this disease. Proponents for early aggressive systemic corticosteroid therapy for amyopathic JDM advocate that this intervention may decrease the likelihood of progression to classic JDM, and/or prevent disease-specific complications of JDM such as calcinosis. Opponents of early intervention with systemic corticosteroids favor expectant management directed toward controlling skin disease, citing the predictable adverse effects of systemic corticosteroids in the face of uncertain benefit. Other therapeutic options for severe and recalcitrant cutaneous disease, including methotrexate, intravenous immunoglobulin, and rituximab, are reviewed, as are treatment options for calcinosis cutis. In weighing the available evidence, the authors conclude that early aggressive treatment of amyopathic JDM with systemic immunosuppressant agents should be avoided in most cases as the risk of these medications will outweigh the measurable benefit. The reported literature suggests a good prognosis for amyopathic JDM. Ongoing clinical follow-up is recommended in all cases to allow early detection of subtle signs of muscle disease.

Glucocorticoid-induced osteoporosis in rheumatic diseases

The aim of this article is to review rheumatological diseases that are associated with glucocorticoid-induced osteoporosis or fractures and to perform a critical analysis of the current guidelines and treatment regimens. The electronic database MEDLINE was searched using the date range of July 1986 to June 2009 and the following search terms: osteoporosis, bone mineral density, fractures, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, vasculitis, juvenile rheumatoid arthritis, juvenile idiopathic arthritis and juvenile dermatomyositis. Osteopenia and osteoporosis respectively account for 1.4 to 68.7% and 5.0 to 61.9% of adult rheumatological diseases. Among juvenile rheumatological disorders, the frequency of low bone mass ranges from 38.7 to 70%. In general, fracture rates vary from 0 to 25%. Although glucocorticoid-induced osteoporosis has a high rate of prevalence among rheumatic diseases, a relatively low number of patients on continuous glucocorticoid treatment receive adequate diagnostic evaluation or preventive therapy. This deficit in patient care may result from a lack of clear understanding of the attributed risks by the patients and physicians, the high complexity of the treatment guidelines and poor patient compliance.

Osteoprotegerin/RANKL system imbalance in active polyarticular-onset juvenile idiopathic arthritis: a bone damage biomarker?

OBJECTIVE

To evaluate the importance of receptor activator of nuclear factor kappaB (RANK)/receptor activator of nuclear factor kappaB ligand (RANKL)/osteoprotegerin (OPG) modulation in active polyarticular juvenile idiopathic arthritis (pJIA) patients with and without bone erosions.

METHODS

Thirty female patients (mean age 11.07+/-3.77 years, range 4-17 years) with active pJIA and 30 healthy gender- and age-matched controls were consecutively selected for this study. All involved articulations were assessed by X-ray and examined for the presence of bone erosions. The serum levels of RANKL and OPG were measured using an enzyme-linked immunosorbent assay (ELISA).

RESULTS

Patients with active pJIA had higher levels of serum RANKL than controls [2.90 (0.1-37.4) vs. 0.25 (0.1-5.7) pg/mL, p = 0.007] and a lower OPG/RANKL ratio [21.25 (1.8-897.6) vs. 347.5 (9-947.8), p = 0.005]. However, levels of OPG were comparable in both groups [55.24 (28.34-89.76) vs. 64.42 (30.68-111.28) pg/mL, p = 0.255]. Higher levels of serum RANKL and a lower OPG/RANKL ratio were also observed in active pJIA patients with bone erosions compared to controls [3.49 (0.1-37.4) vs. 0.25 (0.1-5.7) pg/mL, p = 0.0115 and 14.3 (1.8-897.6) vs. 347.5 (9-947.8), p = 0.016]. However, RANKL levels and OPG/RANKL ratio were similar in pJIA patients without bone erosion and controls [1.75 (0.1-10.9) vs. 0.25 (0.1-5.7) pg/mL, p = 0.055 and 29.2 (3.3-756.8) vs. 347.5 (9-947.8), p = 0.281].

CONCLUSION

These data suggest that active pJIA with bone erosions is associated with high serum levels of RANKL and a low OPG/RANKL ratio, indicating that these alterations may reflect bone damage in this disease.