Steroid-induced osteoporosis in systemic lupus erythematosus

Combined application of mesenchymal stem cells and different glucocorticoid dosing alleviates osteoporosis in SLE murine models

OBJECTIVE

Bone mesenchymal stem cells (BMSCs) have been tentatively applied in the treatment of glucocorticoid-induced osteoporosis (GIOP) and systemic lupus erythematosus (SLE). However, the effects of BMSCs on osteoporosis within the context of glucocorticoid (GC) application in SLE remain unclear. Our aim was to explore the roles of BMSCs and different doses of GC interventions on osteoporosis in SLE murine models.

METHODS

MRL/MpJ-Faslpr mice were divided into eight groups with BMSC treatment and different dose of GC intervention. Three-dimensional imaging analysis and hematoxylin and eosin (H&E) staining were performed to observe morphological changes. The concentrations of osteoprotegerin (OPG) and receptor activator of nuclear factor κB ligand (RANKL) in serum were measured by enzyme-linked immunosorbent assay (ELISA). The subpopulation of B cells and T cells in bone marrows and spleens were analyzed by flow cytometry. Serum cytokines and chemokines were assessed using Luminex magnetic bead technology.

RESULTS

BMSCs ameliorated osteoporosis in murine SLE models by enhancing bone mass, improving bone structure, and promoting bone formation through increased bone mineral content and optimization of trabecular morphology. BMSC and GC treatments reduced the number of B cells in bone marrows, but the effect was not significant in spleens. BMSCs significantly promoted the expression of IL-10 while reducing IL-18. Moreover, BMSCs exert immunomodulatory effects by reducing Th17 expression and rectifying the Th17/Treg imbalance.

CONCLUSION

BMSCs effectively alleviate osteoporosis induced by SLE itself, as well as osteoporosis resulting from SLE combined with various doses of GC therapy. The therapeutic effects of BMSCs appear to be mediated by their influence on bone marrow B cells, T cell subsets, and associated cytokines. High-dose GC treatment exerts a potent anti-inflammatory effect but may hinder the immunotherapeutic potential of BMSCs. Our research may offer valuable guidance to clinicians regarding the use of BMSC treatment in SLE and provide insights into the judicious use of GCs in clinical practice.

Could GILZ Be the Answer to Glucocorticoid Toxicity in Lupus?

Glucocorticoids (GC) are used globally to treat autoimmune and inflammatory disorders. Their anti-inflammatory actions are mainly mediated via binding to the glucocorticoid receptor (GR), creating a GC/GR complex, which acts in both the cytoplasm and nucleus to regulate the transcription of a host of target genes. As a result, signaling pathways such as NF-κB and AP-1 are inhibited, and cell activation, differentiation and survival and cytokine and chemokine production are suppressed. However, the gene regulation by GC can also cause severe side effects in patients. Systemic lupus erythematosus (SLE or lupus) is a multisystem autoimmune disease, characterized by a poorly regulated immune response leading to chronic inflammation and dysfunction of multiple organs, for which GC is the major current therapy. Long-term GC use, however, can cause debilitating adverse consequences for patients including diabetes, cardiovascular disease and osteoporosis and contributes to irreversible organ damage. To date, there is no alternative treatment which can replicate the rapid effects of GC across multiple immune cell functions, effecting disease control during disease flares. Research efforts have focused on finding alternatives to GC, which display similar immunoregulatory actions, without the devastating adverse metabolic effects. One potential candidate is the glucocorticoid-induced leucine zipper (GILZ). GILZ is induced by low concentrations of GC and is shown to mimic the action of GC in several inflammatory processes, reducing immunity and inflammation in in vitro and in vivo studies. Additionally, GILZ has, similar to the GC-GR complex, the ability to bind to both NF-κB and AP-1 as well as DNA directly, to regulate immune cell function, while potentially lacking the GC-related side effects. Importantly, in SLE patients GILZ is under-expressed and correlates negatively with disease activity, suggesting an important regulatory role of GILZ in SLE. Here we provide an overview of the actions and use of GC in lupus, and discuss whether the regulatory mechanisms of GILZ could lead to the development of a novel therapeutic for lupus. Increased understanding of the mechanisms of action of GILZ, and its ability to regulate immune events leading to lupus disease activity has important clinical implications for the development of safer anti-inflammatory therapies.

Role of vitamin D deficiency in systemic lupus erythematosus incidence and aggravation

Vitamin D is one of the main groups of sterols; playing an important role in phospho-calcic metabolism. The conversion of 7-dehydrocholesterol to pre- vitamin D3 in the skin, through solar ultraviolet B radiation, is the main source of vitamin D. Since lupus patients are usually photosensitive, the risk of developing vitamin D deficiency in is high in this population. Although evidences showed the connotation between systemic lupus erythematosus (SLE) and vitamin D through which SLE can lead to lower vitamin D levels, it is also important to consider the possibility that vitamin D deficiency may have a causative role in SLE etiology. This paper analyzes existing data from various studies to highlight the role of vitamin D deficiency in SLE occurrence and aggravation and the probable efficacy of vitamin D supplementation on SLE patients. We searched “Science Direct” and “Pub Med” using “Vitamin D” and “SLE” for finding the studies focusing on the association between vitamin D deficiency and SLE incidence and consequences. Evidences show that vitamin D plays an important role in the pathogenesis and progression of SLE and vitamin D supplementation seems to ameliorate inflammatory and hemostatic markers; so, can improve clinical subsequent.

Burden of corticosteroid use in patients with systemic lupus erythematosus: results from a Delphi panel

Corticosteroid-related adverse events (AEs) are commonly reported in systemic lupus erythematosus (SLE), but are often under-represented in claims data. The most common corticosteroid-related AEs are not necessarily the most costly. The present study aimed to examine corticosteroid-related AE rates and identify the associated cost consequences in patients with SLE from the perspective of rheumatologists treating SLE in the United States (US). A modified Delphi process and RAND Appropriateness Method was used to estimate corticosteroid-related AEs and costs based on data from SLE-treating US rheumatologists and estimates from alternative sources. The panel (n=10) participated in two web-based questionnaires, covering disease severity, corticosteroid use, corticosteroid-related AEs, and resource utilization associated with treatment of the AEs. Eight members of the panel then participated in a guided discussion by interactive teleconference, in which the costs associated with specific corticosteroid-related AEs were also discussed. Consensus was achieved in the teleconference when a single response category (consensus values from 1 to 4 [4=strongly agree, 1=strongly disagree]) accounted for ≥80% of responses. Thirteen consensus statements were developed following two Delphi rounds. Costs were estimated for eight corticosteroid-associated AEs from the panel of rheumatologists. In the patients with SLE treated by these physicians, 41.5% were considered to have mild disease, 36.5% moderate disease, and 22.0% severe disease. The number of specialist visits, corticosteroid use, and corticosteroid dose increased with disease severity. The estimated rates of all AEs (except for cataracts) were at least doubled in patients receiving corticosteroid doses>20 mg/day compared with ≤20 mg/day. The highest estimated mean total costs of an event (for the required treatment duration for one patient) were for avascular necrosis ($14,460) and serious infection ($11,660). The costs of more common AEs, such as osteoporosis, obesity, diabetes, and fractures, ranged from $1190 to $8220. Ten rheumatologists concluded that as disease severity increases, corticosteroid doses increased. Greater utilization of resources is needed to manage patients and corticosteroid-related AEs.

Safety profile and clinical activity of sifalimumab, a fully human anti-interferon α monoclonal antibody, in systemic lupus erythematosus: a phase I, multicentre, double-blind randomised study

BACKGROUND

Type I interferons (IFNs) appear to play a central role in disease pathogenesis in systemic lupus erythematosus (SLE), making them potential therapeutic targets.

METHODS

Safety profile, pharmacokinetics, immunogenicity, pharmacodynamics and clinical activity of sifalimumab, an anti-IFNα monoclonal antibody, were assessed in a phase I, multicentre, randomised, double-blind, dose-escalation study with an open-label extension in adults with moderately active SLE.

SUBJECTS

received one intravenous dose of sifalimumab (n=33 blinded phase, 0.3, 1, 3, 10 or 30 mg/kg; n=17 open-label, 1, 3, 10 or 30 mg/kg) or placebo (n=17). Each phase lasted 84 days.

RESULTS

Adverse events (AEs) were similar between groups; about 97% of AEs were grade 1 or 2. All grade 3 and 4 AEs and all serious AEs (2 placebo, 1 sifalimumab) were deemed unrelated to the study drug. No increase in viral infections or reactivation was observed. Sifalimumab caused dose-dependent inhibition of type I IFN-induced mRNAs (type I IFN signature) in whole blood and corresponding changes in related proteins in affected skin. Exploratory analyses showed consistent trends toward improvement in disease activity in sifalimumab-treated versus placebo-treated subjects. A lower proportion of sifalimumab-treated subjects required new or increased immunosuppressive treatments (12% vs 41%; p=0.03) and had fewer Systemic Lupus Erythematosus Disease Activity Index flares (3% vs 29%; p=0.014).

CONCLUSIONS

Sifalimumab had a safety profile that supports further clinical development. This trial demonstrated that overexpression of type I IFN signature in SLE is at least partly driven by IFNα, and exploratory analyses suggest that IFNα inhibition may be associated with clinical benefit in SLE. Trial registration number NCT00299819.

Bone geometry profiles in women with and without SLE

Recent studies have reported an increased risk of fracture among patients with systemic lupus erythematosus (SLE) in comparison with the general population. The aim of this study was to examine associations between SLE status and bone geometry in white and African-American women. We compared hip BMD and bone geometry parameters among SLE women and control individuals using hip structure analysis (HSA). One-hundred and fifty-three dual-energy X-ray absorptiometry (DXA) scans from the Study of Lupus Vascular and Bone Long Term Endpoints (68.7% white and 31.3% African American) and 4920 scans from the Third National Health and Nutrition Examination Survey (59.3% white and 40.7% African American) were analyzed. Linear regression was used to examine BMD and bone geometry differences by SLE status and by race/ethnicity after adjusting for age and BMI. Significant differences were detected between SLE and control women. Among white women, age-adjusted BMD (g/cm(2)), section modulus (cm(3)), and cross-sectional areas (cm(2)) were lower among SLE women than among control women at the narrow neck (0.88 versus 0.83 g/cm(2), 1.31 versus 1.11 cm(2), and 2.56 versus 2.40 cm(2), p < 0.001, p < 0.01, and p < 0.0001, respectively), whereas buckling ratio was increased (10.0 versus 10.6, p < 0.01). Likewise, BMD, section modulus, and cross-sectional areas were decreased among African-American SLE women at all subregions, whereas buckling ratios were increased. There were significant bone geometry differences between SLE and control women at all hip subregions. Bone geometry profiles among SLE women were suggestive of increased fragility.

Mediation of nonerosive arthritis in a mouse model of lupus by interferon-alpha-stimulated monocyte differentiation that is nonpermissive of osteoclastogenesis

OBJECTIVE

In contrast to rheumatoid arthritis (RA), the joint inflammation referred to as Jaccoud's arthritis that occurs in systemic lupus erythematosus (SLE) is nonerosive. Although the mechanism responsible is unknown, the antiosteoclastogenic cytokine interferon-alpha (IFNalpha), whose transcriptome is present in SLE monocytes, may be responsible. This study was undertaken to examine the effects of IFNalpha and lupus on osteoclasts and erosion in the (NZB x NZW)F(1) mouse model of SLE with K/BxN serum-induced arthritis.

METHODS

Systemic IFNalpha levels in (NZB x NZW)F(1) mice were elevated by administration of AdIFNalpha. SLE disease was marked by anti-double-stranded DNA (anti-dsDNA) antibody titer and proteinuria, and Ifi202 and Mx1 expression represented the IFNalpha transcriptome. Microfocal computed tomography was used to evaluate bone erosions. Flow cytometry for CD11b and CD11c was used to evaluate the frequency of circulating osteoclast precursors (OCPs) and myeloid dendritic cells (DCs) in blood.

RESULTS

Administration of AdIFNalpha to (NZB x NZW)F(1) mice induced osteopetrosis. (NZB x NZW)F(1) mice without autoimmune disease were fully susceptible to focal erosions in the setting of serum-induced arthritis. However, (NZB x NZW)F(1) mice with high anti-dsDNA antibody titers and the IFNalpha transcriptome were protected against bone erosions. AdIFNalpha pretreatment of NZW mice before K/BxN serum administration also resulted in protection against bone erosion (r(2) = 0.4720, P < 0.01), which was associated with a decrease in the frequency of circulating CD11b+CD11c- OCPs and a concomitant increase in the percentage of CD11b+CD11c+ cells (r(2) = 0.6330, P < 0.05), which are phenotypic of myeloid DCs.

CONCLUSION

These findings suggest that IFNalpha in SLE shifts monocyte development toward myeloid DCs at the expense of osteoclastogenesis, thereby resulting in decreased bone erosion.

Efficacy and safety of infliximab in active SLE: a pilot study

Tumour necrosis factor-alpha (TNF-alpha) plays a major role in propagating the inflammatory processes responsible for tissue damage in systemic lupus erythematosus (SLE) and is overexpressed both systemically and locally in this disease. Hence, this pilot study was carried out to assess the safety and efficacy of TNF blockade in patients with active SLE. A total of 46 individuals (27 patients with active SLE and 19 healthy control volunteers) were the subjects of this study. Nine patients with SLE were allocated to treatment arm and 18 were allocated to control arm. In addition to conventional treatment, treatment arm received infliximab infusions 3 mg/kg body weight at 0, 2, 6 weeks and then q 8 weeks for a total of 24 weeks, that is, a total of five doses. Patients were closely monitored for infection. Clinical, laboratory and treatment data were entered into a pre-designed proforma. Health status (SF-36), patient global assessment (PGA) of disease activity, disease activity scores by SLEDAI and organ damage by SLICC/ACR-DI (American College Rheumatology) were measured at baseline and end of the study. Relevant immunological studies included serum levels of TNF-alpha and soluble TNF receptors-1 (p55 srTNF-alpha) and -2 (p75 srTNF-alpha), C3 and C4 complement levels, anti-dsDNA antibody titres (IgM, IgG and IgA isotypes), anti-cardiolipin titres (IgM, IgG and IgA isotypes) and anti-beta2GPI (Glycoprotein I) antibody titres (IgM, IgG and IgA isotypes). Four patients from treatment arm dropped out due to infliximab infusion reaction and 12 patients dropped out from the control arm. The treatment group showed significantly greater improvement in Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Improvements in several SF-36 subscales, PGA and VAS-Fatigue (Visual Analogue Scale) were also greater in the treatment group but did not achieve statistical significance. The mean levels of TNF-alpha, soluble TNF receptors-1 (p55 srTNF-alpha) and -2 (p75 srTNF-alpha) were higher in the SLE group compared with the healthy controls but did not change significantly over the study period. We did not face any safety issues with infliximab in this study. In view of improvement in several SLE parameters and good safety profile of infliximab, anti-TNF-alpha therapy is an interesting candidate approach for treating SLE.

Vitamin D deficiency in patients with active systemic lupus erythematosus

We investigated the effects of disease activity on bone metabolism in 36 patients with systemic lupus erythematosus (SLE). Changes in bone remodeling were not explained by corticosteroid use. A high prevalence of 25OHD deficiency in SLE patients indicates the need for vitamin D replacement, mainly during high disease activity periods.

INTRODUCTION

We investigated the effects of SLE disease activity on bone metabolism, their relation to inflammatory cytokines and vitamin D levels.

METHODS

We performed a cross-sectional analysis of 36 SLE patients classified according to the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) in high activity (group I: 12 patients, mean age 29.6 years) or in minimal activity (group II: 24 patients, mean age 30.0 years), and compared them to normal controls (group III: 26 women, 32.8 years). Serum calcium, phosphorus, parathyroid and sex hormones, bone remodeling markers, interleukin (IL)-6, soluble IL-6 receptor (sIL-6R), IL-1, tumor necrosis factor-alpha (TNF), 25-hydroxivitamin D (25OHD), and 1,25-dihydroxyvitamin D3 were measured, plus bone mineral density.

RESULTS

All cytokines were significantly higher in SLE groups; IL-6 could differentiate SLE patients from controls. In group I, 25OHD levels were lower (P < 0.05), which was related to the SLEDAI (R = -0.65, P < 0.001). In multiple regression analysis, the 25OHD level was associated with SLEDAI, osteocalcin and bone-specific alkaline phosphatase. The SLEDAI score was positively correlated with all measured cytokines and especially TNF (R = 0.75, P < 0.001).

CONCLUSIONS

SLE patients demonstrated changes in bone remodeling strongly related to disease activity. A high prevalence of 25OHD deficiency was observed in SLE patients, indicating the need for vitamin D replacement.

Therapy Insight: osteoporosis and osteonecrosis in systemic lupus erythematosus

Survival of patients with systemic lupus erythematosus (SLE) has improved over the past decade, thanks to improved treatment of the disease, which now results in fewer fatal complications. This improvement has allowed physicians to focus their attention on the prevention of organ damage caused by this chronic, inflammatory disease, and by the medications used to control the disease. Osteoporosis is common in SLE patients; risk factors for osteoporosis include prolonged use of glucocorticoids, cyclophosphamide and possibly gonadotropin-releasing-hormone agonists. In premenopausal women with SLE, inflammation or SLE-related medications can increase bone turnover, which eventually weakens bone architecture, then reduces bone strength and increases the risk of fracture. Prevention and treatment of osteoporosis in SLE patients should entail a multifaceted approach. Levels of calcium, vitamin D and homocysteine should be evaluated, and age-appropriate supplementation instituted. The bone loss that results from systemic inflammation should be treated by reduction of the inflammation with glucocorticoids, potent anti-inflammatory agents or antiresorptive agents. The efficacy of this therapy can be monitored using bone mineral density scans. This Review briefly discusses the pathophysiology of the localized and generalized osteoporosis and osteonecrosis in SLE patients and recommends therapies to both prevent and treat these unfortunate complications of this disease.

Pathogenesis and Prevention of Bone Loss in Patients Who Have Kidney Disease and Receive Long-Term Immunosuppression

The coexistence of kidney disease with a need for immunosuppressive therapy leads to the convergence of several threats to bone. These comprise general effects of the primary disease, e.g., inflammatory state, more specific effects of acute renal failure or chronic kidney disease, and effects of therapies. Multisystem inflammatory disease that requires immunosuppression is associated frequently with kidney damage, and any reduction of kidney function that takes the patient into or beyond chronic kidney disease stage 2 for more than a short time is likely to have a negative impact on bone health. Bone mineral density frequently is low and fracture rates are high, although correlations often are poor. Chronic inflammation leads to local and systemic imbalance between bone formation and resorption. Upregulation of NF-kappabeta ligand (RANKL) and variable downregulation of osteoprotegerin are implicated, and bone health may improve in response to treatment of the inflammatory state. Certain immunosuppressive agents, especially glucocorticoids and calcineurin inhibitors, contribute further to bone loss. Antiresorptive agents such as bisphosphonates are used widely and, although able to prevent loss of bone mineral density, have uncertain effects on fracture rates. Augmentation of anabolic activity is desirable but elusive. Synthetic parathyroid hormone is untested but has potential. Manipulation of the RANKL/osteoprotegerin system now is feasible using antibodies to RANKL or synthetic osteoprotegerin. In the future, manipulation of the calcium-sensing receptor using calcimimetic or calcilytic agents may allow the anabolic effects of parathyroid hormone to be harnessed to good effect. With all of these therapies, it will be important to assess response in relation to important clinical end points such as fracture.

Pamidronate therapy for preventing steroid-induced osteoporosis in children with nephropathy

BACKGROUND

Steroid-induced osteoporosis (SIO) is a serious complication of long-term steroid therapy and is of particular concern in growing children. Recently bisphosphonates have been applied in the treatment or prevention of SIO. We investigated the efficacy of pamidronate on SIO in childhood nephropathy patients receiving long-term corticosteroid therapy.

METHODS

Forty-four children receiving high doses of steroids were enrolled in the study. There was no history of bone, liver, or endocrine disease. Patients were randomly classified into two groups, the control group and the study group. All patients received corticosteroids for 3 months. Control group took oral calcium supplements (500 mg/day) only, and the study group oral calcium and pamidronate (125 mg) for 3 months. Biochemical tests, long bone radiography, and bone mineral density (BMD) were performed in the first month and 3 months later in all patients.

RESULTS

The differences in the results of biochemical tests such as serum calcium, BUN, and creatinine level obtained in the first month and three months later were not of statistical significance in both the control and the study groups. However, the mean BMD of the lumbar spine decreased from 0.654 +/- 0.069 (g/cm2) to 0.631 +/- 0.070 (g/cm2) in the control group (p = 0.0017), while it did not in the study group from 0.644 +/- 0.189 (g/cm2) to 0.647 +/- 0.214 (g/cm2).

CONCLUSIONS

Pamidronate appears to be effective in preventing SIO in children with nephropathy requiring long-term steroid therapy. Further long-term follow-up studies regarding the efficacy and side effects appear to be necessary to set a more solid basis for such pediatric uses of bisphosphonates such as pamidronate.

High prevalence of vertebral deformity in premenopausal systemic lupus erythematosus patients

In this paper we searched for vertebral deformities in a group of 70 premenopausal systemic lupus erythematosus (SLE) patients (31.8 +/- 8.1 years old) and compared them to a matched control group of 22 healthy women (32.0 +/- 8.9 years old). Patients and controls performed spine X-ray (XR) morphometry and lumbar spine and femoral neck bone mineral density (BMD). Clinical data was obtained by a questionnaire and charts review. Thoracic or lumbar spine fracture was observed in 15 (21.4%) SLE patients, while no deformities were found in the control group (P = 0.018). BMD was not different amongst SLE patients and controls and between SLE patients with or without deformities. Although BMD could not predict what patient have deformity, seven patients (46.6%) with deformity had a lumbar spine or femoral neck Z-score less than - 1 SD [median = -0.59 (-3.72 to +0.88) and -0.20 (-4.05 to + 1.87)] respectively. In addition, we found a negative correlation between number of fracture per patient and lumbar spine and femoral neck BMD (R = 0.58, P = 0.04 and R = 0.84, P = <0.0001 respectively). No significant correlation was found between number of deformities and clinical data. This is the first study to search for vertebral deformities in SLE patients and to demonstrate a high prevalence of deformities in a relative young SLE population. These findings bring up the necessity to look for spine deformities in this group of women regardless the BMD.

Bone mineral density in postmenopausal Chinese patients with systemic lupus erythematosus

The objective was to study the bone mineral density (BMD) and its clinical determinants in a cohort of postmenopausal patients with systemic lupus erythematosus (SLE). All postmenopausal SLE patients receiving long term glucocorticoids were identified from our medical clinics. Lumbar and femoral BMDs were measured by dual X-ray absorptiometry. Clinical determinants of BMD were studied by simple and multiple linear regression. Variables evaluated were: age, body mass index, parity, duration of menopause, smoking and alcohol drinking, duration of SLE and steroid treatment, cumulative prednisone dose, clinical and serological profile, disease activity, damage index and the use of medications. In total, 34 patients were studied. The mean age was 52.9+/-4.9 years and the median duration of SLE was 75.5 months. The mean duration of menopause was 5.2+/-3.9 years and the daily maintenance dose of prednisone was 4.0+/-2.5 mg/day. At the lumbar spine, 33% of the patients were osteopenic and 48% were osteoporotic. Two patients had thoracic and lumbar vertebral compression fractures. At the nondominant femoral neck, 74% of patients were osteopenic but only 3% was osteoporotic. In a multivariate model, the current or past use of hydroxychloroquine (HCQ) was associated with a higher spinal BMD. The presence of anti-Sm and the absence of anti-Ro were associated with a higher femoral BMD. It was concluded that osteoporosis, especially at the spine, is a common and serious problem in postmenopausal Chinese SLE patients receiving long term glucocorticoid therapy. Active intervention should be considered. The protective role of HCQ has to be confirmed with further studies.

Longitudinal follow-up of bone mineral density in children with nephrotic syndrome and the role of calcium and vitamin D supplements

BACKGROUND

We previously have demonstrated that children with idiopathic nephrotic syndrome (INS) are at risk of metabolic bone disease (MBD). In this study, we report the longitudinal follow-up of these children and the role of calcium and vitamin D supplements.

METHODS

We prospectively studied 100 consecutive children with INS. They were treated with prednisone. All were subjected to a baseline clinical, biochemical and radiological evaluation. They were initiated on calcium (500 mg/day) and vitamin D3 (200 IU/day) supplements, followed by a repeat assessment. The primary outcome measure was the Deltaz score (difference between the initial and final z scores) on dual energy X-linked absorptiometry (DEXA). A univariate and multivariate analysis using stepwise linear regression was performed for factors predictive of an improved Deltaz score.

RESULTS

Of the 88 children that completed the study, the majority (n = 54) had improved bone mineral density (BMD) at the spine, and another 25 children had stable BMD on calcium and vitamin D3 supplements. The mean spinal BMD values were significantly better on follow-up (0.607+/-0.013 g/cm2) as compared with baseline values (0.561+/-0.010 g/cm2) (P<0.0001). The interval between initial and follow-up assessment was 1.5+/-0.07 years. Children who were on these supplements (n = 73) had a significantly improved z score as compared with those who did not receive them (n = 15) (P = 0.008). On multivariate analysis, the factors predictive of an improved z score were: younger age (P<0.0001), calcium and vitamin D3 supplement (P<0.0001), greater dietary calcium intake (P = 0.022) and lower interval steroid dose (P = 0.001).

CONCLUSIONS

Children with greater steroid doses were likely to have low BMD on follow-up. Calcium and vitamin D supplements may help in improving BMD in children with INS.

Secondary osteoporosis: underlying disease and the risk for glucocorticoid-induced osteoporosis

BACKGROUND

Chronic diseases of many organ systems require long-term (>or=1 year) treatment with glucocorticoids. Owing to the catabolic activity of glucocorticoid therapy, osteoporosis is a potential complication.

OBJECTIVES

This review discusses glucocorticoid-induced bone loss and the factors, including underlying disease, that increase the risk for osteoporosis. Therapeutic options for the prevention and treatment of glucocorticoid-induced osteoporosis (GIO) also are reviewed.

METHODS

A review of the English-language literature was conducted using the MEDLINE database and proceedings from scientific meetings. Search terms including glucocorticoid-induced osteoporosis, bone loss, and fracture were used to refine the search, and preference was given to studies published after 1990.

RESULTS

Long-term glucocorticoid treatment causes bone loss that is most precipitous in the first 6 months. Patients treated with glucocorticoids have additional risk factors for bone loss and osteoporosis that are associated with their primary disease. Chronic diseases can cause changes in bone metabolism, leading to bone loss in addition to that induced by glucocorticoids alone. Bone loss can be minimized through proper nutrition, weight-bearing exercise, calcium and vitamin D supplementation, and, where indicated, bisphosphonate treatment. The American College of Rheumatology Ad Hoc Committee on Glucocorticoid-Induced Osteoporosis guidelines recommend bisphosphonates for minimizing bone loss and fracture risk in patients at risk for GIO. Risedronate is indicated for the prevention and treatment of GIO, and alendronate is indicated for its treatment. Both risedronate and alendronate increase bone mineral density in patients at risk for GIO. Risedronate significantly reduces the incidence of vertebral fractures after 1 year of treatment (P<0.05). The effectiveness and tolerability of the bisphosphonates have not been established in pregnant women or pediatric patients.

CONCLUSIONS

Men and women initiating long-term glucocorticoid treatment and those with GIO should be concomitantly treated with effective osteoporosis therapy to reduce fracture risk and counseled on preventive lifestyle changes.

Are children with idiopathic nephrotic syndrome at risk for metabolic bone disease?

BACKGROUND

Children with idiopathic nephrotic syndrome (INS) may be at risk for metabolic bone disease (MBD) because of biochemical derangements caused by the renal disease, as well as steroid therapy. No large study to date has shown conclusively that these children are prone to MBD.

METHODS

We prospectively studied 100 consecutive children with INS for clinical, biochemical, and radiological evidence of MBD. These children were treated with prednisone as follows: initial episode, prednisone, 60 mg/m2/d for 6 weeks, followed by 40 mg/m2 on alternate days for 6 weeks. Relapses were treated with 60 mg/m2/d until remission for 3 days, followed by 40 mg on alternate days for 4 weeks and tapered by 10 mg/m2/wk. Osteoporosis is defined as a bone mineral density (BMD) value evaluated by dual-energy X-linked absorptiometry of the lumbar spine of a z score of 2.5 SDs less than the mean. Univariate and multivariate analyses were performed to analyze for factors predictive of low BMD z score. Children were divided into two groups: those who had received repeated courses of steroid therapy (group II: frequent relapsers (FRs), steroid dependent (SD), or steroid nonresponders (SNRs) versus those who had received infrequent courses (group I: infrequent relapsers).

RESULTS

Twenty-two of 100 children (22%) had osteoporosis. Comparing clinical features, we observed that 6 of 70 children in group II were symptomatic (hypocalcemic signs) compared with none of 30 children in group I (P = 0.10). However, children in group II had significantly lower mean BMD z scores compared with group I (-1.65 +/- 1.35 versus -1.08 +/- 1.0; P = 0.01). Also, 20 of 70 children in group II had osteoporosis compared with 2 of 30 children in group I (P = 0.012). Children in group II had been administered significantly greater doses of steroids compared with group I (P < 0.00001). On multivariate analysis, factors predictive of a low BMD score were older age at onset (P = 0.000), lower total calcium intake (P = 0.000), and greater cumulative steroid dose (P = 0.005).

CONCLUSION

Children with INS are at risk for low bone mass, especially those administered higher doses of steroids (FRs, SD, or SNRs). These children should undergo regular BMD evaluations, and appropriate therapeutic interventions should be planned.

Osteoporosis screening in systemic lupus erythematosus: impact of disease duration and organ damage

The aim of the present study was to assess the effects of disease severity and demonstrable organ damage as risk factors for the development of osteoporosis in systemic lupus erythematosus (SLE). Sixty-four SLE patients were included. Mean disease duration was 7.7 +/- 5.7 y. Thirty-two patients had persistent organ damage, defined as SLICC-ACR damage score > or = 1. Disease activity measured by SLAM-2 ranged from 3 to 27. Bone mineral density (BMD) measurements were performed with dual X-ray absorptiometry. In addition, biochemical markers of bone metabolism were studied. BMD was inversely correlated with disease duration, damage score and cumulative glucocorticoid intake, but no correlation was found for current glucocortioid use or with markers of bone metabolism. In a multivariate analysis, body weight, disease duration and damage index fitted best for the prediction of BMD at both lumbar spine and femoral neck. Seven out of 64 patients had osteoporosis according to WHO criteria. In conclusion, severe osteoporosis is uncommon in lupus patients. Disease activity and severity were no major risk factors for loss of BMD in this study, but persistent non-bone-related organ damage was significantly linked to the presence of osteoporosis measured as decreased BMD. Our data suggest that, in addition to patients receiving glucocorticoids, patients with an SLICC-ACR > or = 1 or a disease duration > or = 7 y might benefit from regular monitoring of BMD as secondary prevention of damage.

Corticosteroid osteoporosis

Corticosteroids are widely used and effective agents for the control of many inflammatory diseases, but corticosteroid osteoporosis is a common problem associated with their long term high dose use. Prevention of corticosteroid osteoporosis is preferable to treatment of established corticosteroid bone loss. Several large double-blind controlled clinical trials in patients with corticosteroid osteoporosis have recently been published that provide new insights into its treatment. Based upon available evidence, the rank order of choice for prophylaxis would be a bisphosphonate followed by a vitamin D metabolite or an oestrogen type medication. Calcium alone appears to be unable to prevent rapid bone loss in patients starting corticosteroids, especially with prednisolone doses at 10 mg a day or greater. If an active vitamin D metabolite is used, calcium supplementation should be avoided unless dietary calcium intake is low. Hormone replacement therapy should be considered if hypogonadism is present. Since vertebral fracture is a common and important complication of high dose corticosteroid therapy, these findings suggest that rapid bone loss and hence fractures, can be prevented by prophylactic treatment. Although the follow-up data is limited, it is likely that such therapy needs to be continued beyond 12 months whilst patients continue significant doses of corticosteroid therapy.

An update on glucocorticoid-induced osteoporosis

In general, bone loss from glucocorticoid treatment occurs rapidly within the first 6 months of therapy. Glucocorticoids alter bone metabolism by multiple pathways; however, the bone loss is greatest in areas rich in trabecular bone. Preventive measures should be initiated early. It is the author's opinion that all subjects initiating treatment with prednisone at 7.5 mg or greater require calcium supplementation (diet plus supplement) at a dose of 1500 mg and vitamin D at a dose of 400 to 800 IU/d. If the patient is going to remain on this dose of glucocorticoid for more than 4 weeks, an antiresorptive agent should be started (e.g., estrogen, bisphosphonate, raloxifene). If a patient has established osteoporosis and is either initiating glucocorticoid therapy or is chronically treated with prednisone at 5 mg d or greater in addition to calcium and vitamin D supplementation, a potent antiresorptive agent (bisphosphonate) should be started. A bone mineral density measurement of either the lumbar spine or the hip may be helpful is assessing an individual's risk of osteoporosis, may improve compliance with treatment, and can be used to monitor the efficacy of the prescribed therapy. There is no reason to withhold treatment for glucocorticoid-induced bone loss until a bone mass measurement is taken, however. In motivated patients, a weight-bearing and resistance exercise program should be prescribed to help retain muscle strength and prevent depression. If hypercalciuria develops with glucocorticoid use, either thiazide diuretics or sodium restriction may be helpful. In patients who continue to lose bone or experience fracture's despite antiresorptive therapy while on glucocorticoids, bone-building anabolic agents (e.g., hPTH 1-34 or PTH 1-84) may be available someday soon.