SLE and osteoporosis: dependence and/or independence on glucocorticoids

Cortical Bone Loss in a Spontaneous Murine Model of Systemic Lupus Erythematosus

Patients with systemic lupus erythematosus (SLE), a chronic inflammatory disease characterized by loss of T- and B-cell tolerance to autoantigens, are at increased risk for osteoporosis and fractures. Mice deficient in Fc gamma receptor IIb (FcγRIIB) exhibit spontaneous SLE and its restoration rescues the disease. To determine whether deleting FcγRIIB affects cortical bone mass and mechanical properties, we analyzed cortical bone phenotype of FcγRIIB knockouts at different ages. FACS analysis revealed that 6-month-old FcγRIIB^-/- mice had increased B220^lowCD138⁺ cells, markers of plasma cells, indicating active SLE disease. In contrast, 3-month-old FcγRIIB^-/- mice did not develop the active SLE disease. µCT analysis indicated that FcγRIIB deletion did not affect cortical bone in 3-month-old mutants. However, 6- and 10-month-old FcγRIIB^-/- males and females had osteopenic cortical bone and the severity of bone loss increased with disease duration. FcγRIIB deletion decreased cross-sectional area, cortical area, and marrow area in 6-month-old males. Cortical area and cortical thickness were decreased in 10-month-old FcγRIIB^-/- males. Lack of FcγRIIB decreased cortical thickness without affecting cortical area in females. However, deletion of a single FcγRIIB allele was insufficient to induce cortical bone loss. The bending strength was decreased in 6- and 10-month-old FcγRIIB-deficient males compared to WT controls. A microindentation analysis demonstrated significantly decreased hardness in both 10-month-old FcγRIIB^-/- males and females. Our data indicate that FcγRIIB contributes to the regulation of cortical bone homeostasis subsequent to SLE development and that deletion of FcγRIIB in mice leads to SLE-like disease associated with cortical bone loss and decreased bending strength and hardness.

Effect of Vitamin D and Calcium Supplementation in Patients with Systemic Lupus Erythematosus

Background:

Systemic lupus erythematosus is a chronic autoimmune disease that increases the risk of suboptimal vitamin D levels.

Aim:

To determine the effects of vitamin D and calcium supplementation on disease activity, related immune markers and bone mineral density in patients with systemic lupus erythematosus.

Subjects and Methods:

Eighty-one patients with systemic lupus erythematosus aged 20–70 years were recruited for this interventional study. Participants were enrolled into the following groups: no corticosteroid treatment (n = 21), corticosteroid treatment but without supplementation (n = 30) and corticosteroid treatment along with oral vitamin D and calcium supplementation (n = 30). Disease activity and laboratory parameters of all participants were measured at baseline and at 6 months. Bone mineral density was assessed using standardized dual-energy X-ray absorptiometry.

Results:

At baseline, none of the patients had a normal vitamin D status. There were no significant correlations between vitamin D status and the studied immune markers or disease activity values before and after supplementation. After 6 months, patients who received supplementation showed significant (P = 0.002) improvements in bone mineral density. In addition, frequency of osteopenia decreased from 40% to 16.7% and that of osteoporosis decreased from 26.7% to 13.3%.

Conclusion:

Vitamin D and calcium supplementation significantly improved the bone mineral density in vitamin D-deficient patients with systemic lupus erythematosus but did not significantly attenuate immune markers or disease activity. Further investigations are recommended with higher doses of vitamin D and longer durations to normalize the vitamin level and, possibly, achieve better disease control.

Bone geometry, volumetric bone mineral density, microarchitecture and estimated bone strength in Caucasian females with systemic lupus erythematosus. A cross-sectional study using HR-pQCT

Patients with systemic lupus erythematosus (SLE) have an increased risk of fracture. We used high resolution peripheral quantitative computed tomography (HR-pQCT) to measure bone geometry, volumetric bone mineral density (vBMD), cortical and trabecular microarchitecture and estimated bone strength by finite element analysis (FEA) at the distal radius and tibia to assess bone characteristics beyond BMD that may contribute to the increased risk of fracture. Thirty-three Caucasian women with SLE (median age 48, range 21-64 years) and 99 controls (median age 45, range 21-64 years) were studied. Groups were comparable in radius regarding geometry and vBMD, but SLE patients had lower trabecular number (-7%, p < 0.05), higher trabecular separation (13%, p < 0.05) and lower FEA-estimated failure load compared to controls (-10%, p < 0.05). In tibia, SLE patients had lower total vBMD (-11%, p < 0.01), cortical area (-14%, p < 0.001) and cortical thickness (-16%, p < 0.001) and higher trabecular area (8%, p < 0.05). In subgroup analyses of the premenopausal participants (SLE n = 21, controls n = 63), SLE patients had significantly lower trabecular bone volume fraction [(BV/TV); -17%, p < 0.01], trabecular number (-9%, p < 0.01), trabecular thickness (-9%, p < 0.05) and higher trabecular separation (13%, p < 0.01) and trabecular network inhomogeneity (14%, p < 0.05) in radius along with lower BV/TV (-15%, p < 0.01) and higher trabecular separation (11%, p < 0.05) in tibia. FEA-estimated bone strength was lower in both radius (-11%, p < 0.01) and tibia (-10%, p < 0.05). In conclusion, Caucasian women with SLE compared to controls had fewer and more widely separated trabeculae and lower estimated bone strength in radius and lower total vBMD, cortical area and thickness in tibia.

Bone disease in newly diagnosed lupus nephritis patients

Introduction

Bone loss in Lupus Nephritis (LN) patients is common and multifactorial. The aim of this study was to evaluate the bone status of newly diagnosed LN patients and their correlation with inflammatory factors involved in LN physiopathology.

Methods

We studied 15 pre-menopausal patients with ≤2 months of diagnosed SLE and LN. Patients with prior kidney or bone disease were excluded. In addition to biochemical evaluation (including 25-hydroxyvitamin D₃ [25(OH)D] and Monocyte Chemotactic Protein (MCP1) dosage), we performed bone biopsies followed by osteoblast culture, histomorphometric and immunohistochemistry analysis.

Results

LN patients presented a mean age of 29.5±10 years, a proteinuria of 4.7±2.9 g/day and an estimated glomerular filtration rate (GFR) of 37(31–87) ml/min/1,73 m². They were on glucocorticoid therapy for 34±12 days. All patients presented vitamin D insufficiency (9.9±4.4 ng/ml, range 4–20). Urinary MCP1 correlated negatively with 25(OH)D (r = −0.53, p = 0.003) and positively with serum deoxypyridinoline (r = 0.53, p = 0.004). Osteoblasts isolated from LN bone biopsies presented a significantly higher expression of MCP-1 when compared to controls (32.0.±9.1 vs. 22.9±5.3 mean fluorescence intensities, p = 0.01). LN patients presented a significantly reduced osteoid volume, osteoid thickness, osteoid surface, mineralization surface and bone formation rate, associated with an increased eroded surface and osteoclast surface. Patient’s bone specimens demonstrated a reduced immunostaining for osteoprotegerin (0.61±0.82 vs. 1.08±0.50%, p = 0.003), and an increased expression of Receptor Activator of NF-κB ligand (RANKL) (1.76±0.92 vs. 0.41±0.28%, p<0.001) when compared to controls.

Discussion

Newly diagnosed LN patients presented a significant disturbance in bone metabolism, characterized by an impaired bone formation and mineralization, associated with an increase in resorption parameters. Glucocorticoid use, vitamin D insufficiency and inflammation might be involved in the physiopathology of bone metabolism disturbance.

The applied basic research of systemic lupus erythematosus based on the biological omics

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by the production of autoantibodies directed against nuclear self-antigens and circulating immune complexes. This results in damages to various organs or systems, including skin, joints, kidneys and the central nervous system. Clinical manifestations of SLE could be diverse, including glomerulonephritis, dermatitis, thrombosis, vasculitis, seizures and arthritis. The complicated pathogenesis and varied clinical symptoms of SLE pose great challenges in the diagnosis and monitoring of this disease. Unfortunately, the etiological factors and pathogenesis of SLE are still not completely understood. It is noteworthy that recent advances in our understanding of the biological omics and emerging technologies have been providing new tools in the analyses of SLE, such as genomics, epigenomics, transcriptomics, proteomics, metabolomics and so on. In this article, we summarize our current knowledge in this field for a better understanding of the pathogenesis, diagnosis and treatment for SLE.

Osteoporosis screening, prevention, and treatment in systemic lupus erythematosus: application of the systemic lupus erythematosus quality indicators

OBJECTIVE

Osteoporosis and fragility fractures are associated with significant morbidity for patients with systemic lupus erythematosus (SLE). New quality indicators (QIs) for SLE advise bone mineral density testing, calcium and vitamin D use, and antiresorptive or anabolic treatment for specific subgroups of patients receiving high-dose steroids.

METHODS

Subjects were participants in the University of California, San Francisco Lupus Outcomes Study, an ongoing longitudinal study of patients with physician-confirmed SLE, in 2007-2008. Patients responded to an annual telephone survey and were queried regarding demographic, clinical, and other health care-related variables. Multiple logistic regression was used to predict receipt of care per the QIs described above.

RESULTS

One hundred twenty-seven patients met the criteria for the formal definitions of the denominators for QI I (screening) and QI II (calcium and vitamin D); 91 met the formal criteria for QI III (treatment). The proportions of patients receiving care consistent with the QIs were 74%, 58%, and 56% for QIs I, II, and III, respectively. In a sensitivity analysis of all steroid users (n = 427 for QI I and II and n = 224 for QI III), rates were slightly lower. Predictors of receiving care varied by QI and by denominator; however, female sex, older age, white race, and longer disease duration were associated with higher-quality care.

CONCLUSION

Bone health-related care in this community-based cohort of SLE patients is suboptimal. Quality improvement efforts should address osteoporosis prevention and care among all SLE patients, especially those receiving high-dose, prolonged steroids.

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.

Epidemiology of Osteoporosis in Rheumatic Diseases

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

Disease damage and low bone mineral density: an analysis of women with systemic lupus erythematosus ever and never receiving corticosteroids

OBJECTIVES

To evaluate the relationship between disease damage and bone mineral density (BMD) in women with systemic lupus erythematosus (SLE).

METHODS

A cross-sectional study was conducted among 307 women with SLE. Patients attended a single clinic visit that included an interview, physical examination, laboratory testing and BMD measurements (hip and/or lumbar spine). Women were stratified by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology cumulative disease damage index (SDI) > or =1 (Damage) vs SDI=0 (No Damage), and prior use of corticosteroids (CS), yielding four groups: (1) Damage/CS(+) (n=138), (2) Damage/CS(-) (n=23), (3) no Damage/CS(-) (n=100), and (4) no Damage/CS(-) (n=46).

RESULTS

Mean age at SLE diagnosis was 32.7 +/- 11.8 yr, 24.4% were African American, 65.0% were premenopausal, and mean SDI +/- S.D. was 1.3 +/- 1.8. In the unadjusted and adjusted models controlling for significant univariate risk factors for osteoporosis, the reference group (Group 1) had significantly lower mean BMD T-scores at the hip and lumbar spine than groups having no disease damage (Groups 3 and 4) independent of CS use status. Similar hip and lumbar spine mean BMD T-scores were observed in women with disease damage with and without CS exposure (Groups 1 and 2).

CONCLUSIONS

Women with SLE having disease damage and no CS use had BMD T-scores at the hip and lumbar spine similar to those of women with disease damage and prior CS use. These findings suggest an association between disease damage and lower BMD T-scores in women with SLE.

Oral pamidronate prevents high-dose glucocorticoid-induced lumbar spine bone loss in premenopausal connective tissue disease (mainly lupus) patients

Glucocorticoid (GC)-induced osteoporosis contributes to chronic damage in patients suffering from connective tissue diseases (CTD) such as systemic lupus erythematosus (SLE). In this study, performed in an highly selected cohort of premenopausal female CTD (mostly lupus) patients, given high-dose GC therapy for severe disease, we show that lumbar spine bone loss can be averted by treatment with oral disodium pamidronate combined with calcium salts and vitamin D3 supplements and not by calcium salts and vitamin D3 supplements alone. We stress the need for optimal GC-induced bone loss prevention therapy in premenopausal patients, a too often neglected issue in patients whose survival has dramatically improved over the last decades.

Frequency of osteopenia in children and young adults with childhood-onset systemic lupus erythematosus

OBJECTIVE

To determine the frequency of osteopenia in patients with childhood-onset systemic lupus erythematosus (SLE) compared with that in healthy matched controls, and to evaluate the relationship between disease-related variables and bone mineral mass.

METHODS

Bone mineral density (BMD) and bone mineral content (BMC) were measured in a cohort of 70 patients with childhood-onset SLE (mean +/- SD disease duration 10.8 +/- 8.3 years, mean +/- SD age 26.4 +/- 9.9 years) and 70 age- and sex-matched healthy controls. BMD and BMC of the femoral neck, lumbar spine, total body, and distal one-third of the radius were measured by dual x-ray absorptiometry. We investigated the relationship between BMC and the following disease variables: cumulative dose of corticosteroids, organ damage, current use of corticosteroids, use of cyclophosphamide, age at disease onset, and disease activity at the time of diagnosis. Biochemical markers of bone metabolism were also measured.

RESULTS

BMD values for the lumbar spine and femoral neck were significantly lower in patients than in healthy controls. The reduction in BMD of the lumbar spine was significantly greater than that of the total body. In multiple linear regression analyses, a higher cumulative corticosteroid dose was significantly associated with lower BMC of the lumbar spine and femoral neck. Decreased lumbar spine BMC was also related to male sex.

CONCLUSION

The frequency of osteopenia was higher in patients with childhood-onset SLE than in matched controls. The lumbar spine was the most seriously affected skeletal site, followed by the femoral neck. The cumulative dose of corticosteroids was shown to be an important explanatory variable for BMC values in the lumbar spine and femoral neck.

Prevalence and predictors of fragility fractures in systemic lupus erythematosus

OBJECTIVE

To establish the prevalence of reduced bone mineral density (BMD) and fractures, and risk factors for fractures, in a cross sectional study of a large cohort of patients with systemic lupus erythematosus (SLE).

METHODS

All SLE patients willing to take part in the study had bone densitometry in 1999/2000 and completed a questionnaire on risk factors for osteoporosis and on drugs used. Accumulated damage was scored using the SLICC/ACR damage index (SDI). Only fractures occurring since the onset of SLE and unrelated to trauma were included, and the SDI score was modified to exclude osteoporotic fractures. Statistical analysis was by chi(2) test, Fisher's exact test, and binary logistic regression.

RESULTS

242 patients were studied, median age 39.9 years (range 18 to 80), median disease duration 7.0 years (range 0 to 42). Of these, 123 (50.8%) had reduced BMD (T score <-1.0) and 25 (10.3%) were in the osteoporotic range (T score <-2.5). Fragility fractures had occurred in 22 patients (9.1%) since diagnosis of SLE. Of these, two (9.1%) had normal BMD and 20 (90.9%) had reduced BMD, while seven (31.8%) were within the osteoporotic range. Non-Afro-Caribbean race and exposure to prednisolone >10 mg daily were significantly associated with reduced BMD, while age and menopause were associated with osteoporosis. The risk factors for fractures were reduced BMD and age.

CONCLUSIONS

Reduced BMD, osteoporosis, and fragility fractures appear to be prevalent in patients with SLE. Steroids were not an independent risk factor for fractures, although their effect could be mediated through reduced bone mineral density.

Osteoporosis in systemic lupus erythematosus: factors associated with referral for bone mineral density studies, prevalence of osteoporosis and factors associated with reduced bone density

The purpose of this study was to evaluate the clinical characteristics of women with systemic lupus erythematosus (SLE) sent for a dual energy X-ray absorptiometry (DEXA) study, and to analyse the factors associated with a lower bone mineral density in these patients. Women with SLE who had a DEXA done between 1 January 1995 and 31 December 2000 were compared with those who did not have DEXA scans performed. SLE patients with osteoporosis (OP) were compared with those with a normal bone density. Of 516 women with SLE, 205 had a DEXA done. These patients had more traditional risk factors for osteoporosis, higher lupus disease activity, renal involvement, increased damage, higher mean steroid dose, increased use of immunosuppressants and occurrence of avascular necrosis. Of the 205 patients with DEXA, 18% had osteoporosis, 48.8% had osteopenia and 33.2% had normal bone mineral density. The two statistically significant predictors of a low bone density were a higher age at time of DEXA (P = 0.0003) and a higher SDI score (P = 0.0019). Osteoporosis is a significant comorbidity in SLE. Lupus patients referred for a DEXA have more traditional risk factors and use more corticosteroids. The main factors associated with a low bone density were however found to be age and increased damage. Interestingly, disease activity and corticosteroid use were not associated with osteoporosis in this study which may suggest other potential causes such as decreased physical activity associated with damage.

Differentiation of in vitro transcriptional repression and activation profiles of selective glucocorticoid modulators

The SAR at C-5 of the 10-methoxy-2,2,4-trimethylbenzopyrano[3,4-f]quinoline core leading to identification of (-) anti 1-methylcyclohexen-3-yl as the optimum substituent that imparts minimal GR mediated in vitro transcriptional activation while maintaining full transcriptional repression is described. The in vitro profile of these candidates in human cell assays relevant to the therapeutic window of glucocorticoid modulators is outlined.

Bone mineral density in systemic lupus erythematosus and its relation to age at disease onset, plasmatic estradiol and immunosuppressive therapy

OBJECTIVE

The aim of this paper was to evaluate bone mineral density (BMD) in patients with systemic lupus erythematosus (SLE), to determine the role of corticosteroids and cytotoxic drugs and to assess estrogen effect on BMD in SLE.

PATIENTS AND METHODS

BMD (DEXA) at lumbar vertebrae (L2-L4) and at femoral neck was performed in 60 pre-menopausal SLE patients and in 64 controls. Estradiol level was measured in all the individuals. Age, age at disease onset, body mass index (BMI), time of disease, disease activity (SLEDAI), prednisone dose at the evaluation, total cumulative and cumulative prednisone dose in the last year and cytotoxic drugs were assessed.

RESULTS

The mean plasmatic estradiol was 175.9 pg/ml in patients and 149.9 in controls. BMD was inferior in patients than that in controls (P < 0.0001). The mean current, cumulative and previous year prednisone doses were, respectively, 19.17 mg/d, 28.78 g and 5.33 g. There was no association between corticosteroids or cytotoxic drug used and low bone mass. The serum concentration of estradiol did not influence the bone mass. The BMI and age at disease onset exhibited an influence on BMD at L2.

CONCLUSIONS

BMD was significantly lower in SLE patients but not related to CS (Corticosteroids)or other drugs; the estradiol in these patients had no effect on BMD. Low BMI interacting with early onset of disease might influence the probability of loss of bone mass.

Can morbidity and mortality of SLE be improved?

Systemic lupus erythematosus (SLE) is the second most common autoimmune disorder (after thyroid disease) in women of childbearing age. Lupus is increasingly being recognized throughout the world's population. The incidence and prevalence of SLE varies among racial and ethnic groups. Lupus patient survival has significantly improved over the past five decades, but a three- to fivefold increased risk of death remains compared with the general population. As lupus patients survive longer, these individuals face a range of complications from the disease itself or consequent to its treatment. Emerging data from epidemiological studies underscore the importance of incorporating race and ethnicity in understanding the risk factors leading to the significant burden of mortality and morbidity associated with this disease. This chapter describes the epidemiology of lupus with a focus on racial and ethnic differences, reviews the mortality associated with the disease, discusses selected complications associated with morbidity related to the disease and highlights areas where we can improve mortality and morbidity.

Nonsteroidal selective glucocorticoid modulators: the effect of C-5 alkyl substitution on the transcriptional activation/repression profile of 2,5-dihydro-10-methoxy-2,2,4-trimethyl-1H-[1]benzopyrano[3,4-f]quinolines

The preparation and characterization of a series of selective glucocorticoid receptor modulators are described. The preliminary structure-activity relationship of nonaromatic C-5 substitution on the tetracyclic quinoline core showed a preference for small lipophilic side chains. Proper substitution at this position maintained the transcriptional repression of proinflammatory transcription factors while diminishing the transcriptional activation activity of the ligand/glucocorticoid receptor complex. The optimal compounds described in this study were the allyl analogue 18 and cyclopentyl analogue 32. These candidates showed slightly less potent, highly efficacious E-selectin repression with significantly reduced levels of glucocorticoid response element activation in reporter gene assays vs prednisolone. Allyl analogue 18 was evaluated in vivo. An oral dose of 18 showed an ED(50) = 1.7 mg/kg as compared to 1.2 mg/kg for prednisolone in the Sephadex-induced pulmonary eosinophilia model and an ED(50) = 15 mg/kg vs 4 mg/kg for prednisolone in the carrageenan-induced paw edema model.

Treatment of lupus with corticosteroids

Through direct signals to the nucleus mediated by the glucocorticoid receptor, exogenous glucocorticoids impact a broad array of cellular functions. DNA binding of the glucocorticoid receptor, depending upon the specific promoter to which the receptor binds, affects gene expression by recruiting transcription factors to the promoter or by interfering with the function of co-factors required for gene transcription. Steroid effects on the adhesion functions and release of products by phagocytic cells are prompt, occurring within hours of administration. Administration of corticosteroids results in rapid depletion of circulating T-cells due to a combination of effects including enhanced circulatory emigration, induction of apoptosis, inhibition of T-cell growth factors, and impaired release of cells from lymphoid tissues. Corticosteroid effects on B-cell function and immunoglobulin production are more delayed. The broad, generally suppressive effects of corticosteroids on the immune response render them useful for the management of most organ system manifestations of lupus. Corticosteroid toxicity in lupus is notable for greater susceptibility to infections, osteoporosis, osteonecrosis and accelerated atherogenesis. Although use of corticosteroids for patients with severe disease manifestations is associated with higher numbers of deaths from infections, overall survival appears to be improved.

Osteoporosis in systemic lupus erythematosus: prevention and treatment

The patient with systemic lupus erythematosus (SLE) is at risk of osteoporosis through several factors: the inflammatory disease itself, disease-related co-morbidity, and its treatment. Bone loss is apparent early in the disease and this may be confounded primarily by treatment with corticosteroids. Patients should be assessed for additional risk factors for osteoporosis and general lifestyle measures adopted. Bone mineral density measurement should be considered in SLE patients at high risk of osteoporosis, particularly those starting corticosteroids and in postmenopausal women. Calcium and vitamin D supplementation provide general prophylaxis and are a suitable first-line option. Hormone replacement should be used in hypogondal subjects unless contra-indicated. In subjects at high fracture risk, particularly in postmenopausal women, bisphosphonate therapy should be considered as these agents have been shown to significantly reduce vertebral fracture risk. These measures should reduce the burden of osteoporosis and fracture in patients with lupus.

Frequency of fractures in women with systemic lupus erythematosus: comparison with United States population data

OBJECTIVE

To describe the frequency of self-reported fractures in a large population-based cohort of women with lupus, to compare the frequency of self-reported fractures between lupus patients and women of similar age in the general population by use of data from the 1994 National Health Interview Survey (NHIS), and to describe the associated risk factors for fracture in women with lupus. This study is a secondary analysis of data collected to assess cardiovascular risk in women with lupus.

METHODS

Fractures and associated risk factors were ascertained by self report in this retrospective cohort study of 702 living women with lupus who were followed up for 5,951 person-years. Self-reported fractures were verified in a subset of patients. A Weibull regression model was used to assess risk factors associated with time from lupus diagnosis to fracture in the univariate and multivariate analyses. Age-specific standard morbidity ratios (SMRs) were calculated to determine whether fracture occurrence was greater than expected in women with lupus.

RESULTS

Eighty-six (12.3%) of 702 women reported at least 1 fracture following the diagnosis of lupus. The sites of the first fracture were the leg (n = 32), foot (n = 16), arm (n = 15), spine (n = 9), rib (n = 7), hip (n = 2), pelvis (n = 2), hand (n = 1), shoulder (n = 1), and finger (n = 1). Fracture risk was increased in the lupus cohort compared with women of similar age from the United States population, using weighted data from the 1994 NHIS (SMR 4.7; 95% confidence interval 3.8, 5.8). Variables in the univariate analysis that were significantly associated (P < 0.05) with time from lupus diagnosis to fracture were older age at lupus diagnosis, longer disease duration, longer duration of corticosteroid use, less use of oral contraceptives, and menopause status. In the multivariate analysis, independent determinants of time from lupus diagnosis to fracture were older age at lupus diagnosis and longer duration of corticosteroid use.

CONCLUSION

Fractures occurred in 12.3% of lupus patients who were followed up for 5,951 person-years. There was nearly a 5-fold increase in fracture occurrence in the women with lupus compared with women from the US population. Older age at lupus diagnosis and longer use of corticosteroids were associated with time from lupus diagnosis to fracture. With increased life expectancy of lupus patients, fracture occurrence is a major threat to the health of these women. Prevention strategies must be directed toward minimizing the occurrence of fractures in these patients.

Urinary excretion of the pyridinium cross-links of collagen in systemic lupus erythematosus

The aim of this study was to measure the urinary excretion of the pyridinium cross-links of collagen and to determine their usefulness as markers of reduced bone mineral density in systemic lupus erythematosus (SLE). All female SLE patients managed at a single centre were invited to participate in a cross-sectional study of urinary pyridinium cross-links excretion (HPLC), bone mineral density (DXA), and SLE-related variables. Ninety-one women with SLE were studied, 35 of whom were postmenopausal. Pyridinoline/Creatinine (Pyd/Cr) and deoxypyridinoline/Cr (Dpd/Cr) levels in postmenopausal women were significantly increased compared with premenopausal values (p = 0.010 and p = 0.004, respectively). Univariate linear regression analysis revealed a significant association of Dpd/Cr with reduced femoral neck and lumbar spine BMD (p = 0.001, p<0.001), and of Pyd/Cr with reduced femoral neck BMD (p = 0.020). In addition, the association of Pyd/Cr with reduced lumbar spine BMD approached significance (p = 0.055). Stepwise multiple linear regression analysis adjusting for other variables confirmed a significant association of Dpd/Cr with reduced lumbar spine BMD (p = 0.006), and a significant association of both Pyd/Cr and Dpd/Cr with postmenopausal status (p = 0.003, p<0.001). It was concluded that in this SLE population, the urinary excretion of Dpd/Cr was a useful marker of reduced BMD at the lumbar spine. Menopausal status was a major predictor of cross-links excretion in SLE.

Role of alfacalcidiol on bone quality and immunomodulation in autoimmune disease and organ transplantation

In autoimmune diseases, as well as in organ transplantation, corticosteroids are often an obligatory part of the treatment regimen. The deleterious effect of corticosteroids on bone metabolism is well known, although still controversial [1-3]. It is easier to maintain bone mass than to restore it. Although the treatment of choice for prevention of bone loss is hormone replacement therapy, it cannot always be applied, and for many reasons compliance is low over the world. Alternative strategies to prevent bone loss are now tried out in many centers. Calcitonin and bisphosphonates are well-known antiresorbing drugs, but costs and long-term efficiency for calcitonin and fear for bone toxicity for the bisphosphonates limits their use for prevention. An attractive strategy to prevent osteoporosis is the treatment with alfacalcidiol because it is a natural product with important effects on bone metabolism in physiological and pharmacological dosages. Calcium absorption from the gut and mineralization of the bone matrix are optimalized by alfacalcidiol. The purpose of this paper is to report on our experience with alfacalcidiol concerning bone mass and quality in corticosteroid-induced osteoporosis in experimental animals and on long-term bone quality in autoimmune diseases and organ transplantation. We have studied the effects of alfacalcidiol on bone mass and quality in ovariectomized animals with and without corticosteroids. In these fundamental studies we have found that alfacalcidiol had a profound protective and curative effect not only on bone mass but also on bone quality as tested by mechanical testing, namely, impact torsional loading test of whole bones. The combination of alfacalcidiol with estrogens was less effective than alfacalcidiol, but more effective than estrogens alone [4-6] (Fig. 1).