Are disease duration and degree of functional impairment determinants of bone loss in rheumatoid arthritis?

Bone phenotypes in rheumatology - there is more to bone than just bone

Osteoarthritis, rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis, all have one clear common denominator; an altered turnover of bone. However, this may be more complex than a simple change in bone matrix and mineral turnover. While these diseases share a common tissue axis, their manifestations in the area of pathology are highly diverse, ranging from sclerosis to erosion of bone in different regions. The management of these diseases will benefit from a deeper understanding of the local versus systemic effects, the relation to the equilibrium of the bone balance (i.e., bone formation versus bone resorption), and the physiological and pathophysiological phenotypes of the cells involved (e.g., osteoblasts, osteoclasts, osteocytes and chondrocytes). For example, the process of endochondral bone formation in chondrocytes occurs exists during skeletal development and healthy conditions, but also in pathological conditions. This review focuses on the complex molecular and cellular taxonomy of bone in the context of rheumatological diseases that alter bone matrix composition and maintenance, giving rise to different bone turnover phenotypes, and how biomarkers (biochemical markers) can be applied to potentially describe specific bone phenotypic tissue profiles.

Skeletal complications of rheumatoid arthritis

Rheumatoid arthritis (RA) is associated with local and systemic inflammation that induces many changes in the skeletal health. Locally, periarticular bone loss and juxta-articular bone erosions may occur while joint ankylosis, generalized bone loss, osteoporosis, and fractures may develop secondary to inflammation. The aim of this narrative review is to summarize the clinical evidence for abnormal skeletal health in RA, the effects of disease modifying anti-rheumatic drugs (DMARDS) on bone health, and the effects of drugs for the prevention or treatment of osteoporosis in the RA population.

Relation of interleukin-6 in rheumatoid arthritis patients to systemic bone loss and structural bone damage

IL-6 plays a key role in local and systemic manifestation of RA. IL-6 is not only a pro-inflammatory cytokine, but also interacts in complex ways with the cells involved in bone remodeling. In RA, IL-6 may indirectly promote osteoclastogenesis by increasing the release of RANK-L by osteoblasts, and it diminishes the proliferation of osteoblasts at late differentiation stages. The aims of this work were to evaluate the level of serum IL-6 and to correlate it with the activity, severity, early development of osteoporosis, and early structural bone damage in RA patients. The following parameters were investigated in 40 RA patients and 20 healthy controls: IL-6 level, BMI, ESR, CRP, CBCs, serum ionized calcium, blood urea, serum creatinine, AST, ALT, anti-CCP, and RF. Bone mineral density was measured by dual-energy X-ray absorptiometry at lumbar spines and femoral neck. Drug history was taken stressing on steroid therapy. Data were processed and analyzed using computer-based program. IL-6 was significantly positively correlated with HAQ1, PTGA, grade of pain, ESR, platelet count, blood urea, AST level, and anti-CCP level; IL-6 showed an inverse significant correlation with T-score. IL-6 was positively correlated with TGC, DAS-28 score, and RF level. No correlation was found between T-score and morning stiffness duration, BMI, CRP, RBC, serum creatinine, and ALT. There was an inverse significant correlation between T-score and HAQ1, SJC, pain grade, DAS-28 score, PTGA, ESR, RF, anti-CCP, and IL-6. Patients with RA on steroid therapy had significantly higher TJC, SJC, and DAS-28 score, anti-CCP, and IL-6 than patients with RA not on steroid therapy. Patients with RA on steroid therapy had significantly lower T-score and lower serum ionized calcium than patients with RA not on steroid therapy. IL-6 has an important role in increasing osteoclastic activity and subsequent bone resorption in the patients with RA. Blocking IL-6 by using IL-6 inhibitors and anti-RANK-L therapy may be effective in inhibiting the inflammatory process and preventing the bone complications of RA disease.

Osteoprotegerin expression in bone marrow by treatment with tocilizumab in rheumatoid arthritis

The aim of this study was to investigate histological changes of bone marrow in response to tocilizumab for rheumatoid arthritis (RA). After tocilizumab therapy, bone marrow tissues were extracted from ten RA patients at the time of total knee arthroplasty (TKA). Control samples were obtained from ten RA patients who underwent MTX mono-therapy. Histological examination of structural differences between the tocilizumab and control groups in bone marrow was performed using hematoxylin and eosin (H&E) to evaluate differences. In immunohistochemical examination, the expression of seven molecules including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), CD68, osteoprotegerin (OPG), receptor activator of nuclear kappa B ligand (RANKL), CD4 and osteopontin (OPN) were compared between two groups. NTx was significantly low at 44.5 ± 2 nM BCE/mM Cr compared with control at 73.2 ± 8 nM BCE/mM Cr. Immunohistochemical examination revealed that the bone marrow tissues of the RA patients who underwent tocilizumab therapy demonstrated significant positive OPG as compared with the control. However, immunohistochemical examinations after tocilizumab revealed that TNF-α, IL-6, CD68, CD4, OPN and RANKL were not significantly different with control of MTX in bone marrow. Therefore, treatment with tocilizumab increased the expression of OPG as the histological changes with respect to inhibit RANKL-related bone resorption of bone marrow in RA.

The utility of clinical decision tools for diagnosing osteoporosis in postmenopausal women with rheumatoid arthritis

Background

Patients with rheumatoid arthritis have a higher risk of low bone mineral density than normal age matched populations. There is limited evidence to support cost effectiveness of population screening in rheumatoid arthritis and case finding strategies have been proposed as a means to increase cost effectiveness of diagnostic screening for osteoporosis. This study aimed to assess the performance attributes of generic and rheumatoid arthritis specific clinical decision tools for diagnosing osteoporosis in a postmenopausal population with rheumatoid arthritis who attend ambulatory specialist rheumatology clinics.

Methods

A cross-sectional study of 127 ambulatory post-menopausal women with rheumatoid arthritis was performed. Patients currently receiving or who had previously received bone active therapy were excluded. Eligible women underwent clinical assessment and dual-energy-xray absorptiometry (DXA) bone mineral density assessment.

Clinical decision tools, including those specific for rheumatoid arthritis, were compared to seven generic post-menopausal tools to predict osteoporosis (defined as T score < -2.5). Sensitivity, specificity, positive predictive and negative predictive values and area under the curve were assessed. The diagnostic attributes of the clinical decision tools were compared by examination of the area under the receiver-operator-curve.

Results

One hundred and twenty seven women participated. The median age was 62 (IQR 56–71) years. Median disease duration was 108 (60–168) months. Seventy two (57%) women had no record of a previous DXA examination. Eighty (63%) women had T scores at femoral neck or lumbar spine less than -1. The area under the ROC curve for clinical decision tool prediction of T score <-2.5 varied between 0.63 and 0.76. The rheumatoid arthritis specific decision tools did not perform better than generic tools, however, the National Osteoporosis Foundation score could potentially reduce the number of unnecessary DXA tests by approximately 45% in this population.

Conclusion

There was limited utility of clinical decision tools for predicting osteoporosis in this patient population. Fracture prediction tools that include risk factors independent of BMD are needed.

Changes in bone mineral density in premenopausal women with rheumatoid arthritis during a two-year follow-up

OBJECTIVE

To ascertain changes in axial bone mineral in premenopausal women with severe rheumatoid arthritis (RA) treated with and without prednisolone (PRED), we conducted a two-year follow-up study of axial bone mineral density (BMD) and bone mineral content (BMC).

METHODS

Premenopausal RA women (n=74) attending wards in the Rheumatism Foundation Hospital, Heinola, Finland were consecutively recruited for a follow-up study of BMD. BMD measurements in the lumbar spine and left proximal femur (femoral neck) were performed using dual X-ray absorptiometry at baseline and after two years. BMD is expressed as BMC per projectional area g/cm2. The Larsen score of 0-100 was assessed at the check-ups. Two RA groups were analyzed: patients receiving prednisolone (n=48), RA with PRED group and without prednisolone (n=26), RA without PRED group. The control group (n=43) comprised age-matched, premenopausal healthy women.

RESULTS

The patients in the RA with PRED group had lower BMD values than those in the RA without PRED group at commencement of follow-up. The mean weight-adjusted BMD percentage change in the lumbar spine to two years was -1.5% in the RA with PRED group, +0.6% in the RA without PRED group and -0.6% among the controls; a significant difference (P=0.030) was found between the RA groups. The mean BMC percentage change to two years in the lumbar spine was -2.2% in the RA with PRED-group (P=0.003), +0.0 in the RA without PRED-group and -0.6% in the control group. Accordingly, the mean weight-adjusted BMD percentage change in the femoral neck to two years was -2.6% in the RA with PRED group, +0.4% in the RA without PRED group and -0.9% among the controls; the difference between the RA groups being again significant (P=0.049). The mean BMC percentage change to two years in the femoral neck was -1.9% (P=0.006), -0.4% and -0.8%, respectively. Mean BMD decreased significantly in both lumbar spine (P=0.002) and femoral neck (P<0.001) only in the RA with PRED group. However, in spite of statistical findings above, when BMD is expressed as BMC per projectional area there was no statistically significant difference between the three groups in the change in BMC or projectional area in the lumbar spine or femoral neck. There was no significant correlation between the change in BMD in lumbar spine or femoral neck and the change in Larsen score among the RA groups.

CONCLUSIONS

We conclude that according to BMC, premenopausal RA women both with and without prednisolone treatment and controls lost bone statistically similarly. It seems that the role of RA itself in the multifactorial development of axial bone mass during the first decade of severe RA is not the most essential issue. We assume that this role will be less important with better treatment of RA than our patients received. The amount of bone loss during treatment with low-grade prednisolone remains controversial.

Bone mineral density in patients with recently diagnosed, active rheumatoid arthritis

OBJECTIVES

Osteoporosis is a well-known extra-articular phenomenon in patients with uncontrolled, long-standing rheumatoid arthritis (RA). In the present study, the extent of osteoporosis and reduced bone mineral density (BMD) and the disease-related and demographic factors that are associated with osteoporosis and reduced BMD were examined in patients with recently diagnosed, active RA.

METHODS

BMD of the total hip and the lumbar spine was measured using dual-energy x ray absorptiometry in 381 patients with recently diagnosed active RA, who had never been treated with DMARDs or corticosteroids. Osteoporosis was defined as a T score <or=-2.5 SD and reduced BMD as Z score <or=-1 SD. Multivariate logistic regression analyses were performed to detect associations of osteoporosis and reduced BMD with disease activity, functional disability, joint damage (Sharp-van der Heijde score) and demographic factors.

RESULTS

Osteoporosis and reduced BMD were found in the spine and/or the hip in 11% and 25%, respectively, of the patients. Longer symptom duration and presence of rheumatoid factor (RF) were the only RA-specific markers for osteoporosis and reduced BMD. Further, postmenopausal status in women, a low body mass index, familial osteoporosis, and, remarkably, male gender, were independently associated with osteoporosis and reduced BMD.

CONCLUSION

In patients with recently diagnosed active RA who had never been treated with DMARDs or corticosteroids, BMD seems to be well-preserved and predominantly related to demographic factors. Longer symptom duration and a positive RF, but not higher disease activity or more joint damage, were related to osteoporosis and reduced BMD.

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.

The effect of low-dose prednisone on bone mineral density in Peruvian rheumatoid arthritis patients

OBJECTIVE

The aim of this study was to determine the difference between bone mineral density (BMD) of rheumatoid arthritis (RA) patients on low-dose prednisone and matched RA patients without prior systemic corticosteroid therapy.

METHODS

Ninety patients attending our clinics and receiving 10 mg/day of prednisone or less for at least the previous 3 consecutive months were studied. The control group comprised 90 selected RA patients without corticosteroid therapy matched for age, race, gender, disease duration, use of methotrexate, postmenopause, and Health Assessment Questionnaire score. The BMD was measured using dual X-ray absorptiometry.

RESULTS

Patients on prednisone had lower BMD than controls (0.94 +/- 0.17 vs 0.96 +/- 0.17 for L2-4 and 0.73 +/- 0.14 vs 0.76 +/- 0.16 for femoral neck), but these differences were not statistically significant (P > 0.05). In post hoc analysis, postmenopausal women on prednisone had more bone loss in femoral neck than controls (0.68 +/- 0.13 vs 0.74 +/- 0.15).

CONCLUSION

Bone mineral density was not significantly reduced by low-dose prednisone in this diverse group of RA patients. A reduction in hip BMD was seen in postmenopausal women on prednisone.

Osteoprotegerin protects against generalized bone loss in tumor necrosis factor-transgenic mice

OBJECTIVE

To investigate the role of tumor necrosis factor (TNF) in systemic bone loss of chronic inflammatory conditions, such as rheumatoid arthritis (RA), and to address the therapeutic potential of osteoclast blockade.

METHODS

We investigated systemic bone changes in human TNF transgenic (hTNFtg) mice, which spontaneously developed severe inflammatory arthritis.

RESULTS

Osteodensitometry revealed a significant decrease in trabecular bone mineral density (BMD) (-37%) in hTNFtg mice, and histomorphometry revealed a dramatic loss of bone volume (-85%) compared with wild-type controls. Osteoclast-covered bone surface and serum levels of deoxypyridinoline crosslinks were significantly elevated, suggesting increased osteoclast-mediated bone resorption in hTNFtg mice. Osteoprotegerin (OPG) completely blocked TNF-mediated bone loss by increasing BMD (+89%) and bone volume (+647%). Most strikingly, formation of primary spongiosa was dramatically increased (+563%) in hTNFtg mice after OPG treatment. Osteoclast-covered bone surface and serum levels of deoxypyridinoline crosslinks were significantly decreased by OPG, suggesting effective blockade of osteoclast-mediated bone resorption. OPG did not influence levels of hTNF, TNF receptor I (TNFRI), interleukin-1beta (IL-1beta), and IL-6. However, OPG decreased bone formation parameters (osteoblast-covered bone surface and serum osteocalcin levels), which were elevated in hTNFtg mice. In contrast to OPG, bisphosphonates and anti-TNF treatment did not affect generalized bone loss in hTNFtg mice. Anti-TNF, however, did not affect levels of TNF and TNFRI at the concentrations tested. These data indicate that generalized bone loss due to increased TNF can be blocked by OPG.

CONCLUSION

OPG may represent a potent tool for preventing generalized loss of bone mass in chronic inflammatory disorders, especially RA.

Bone quality and bone mass as assessed by quantitative ultrasound and dual energy x ray absorptiometry in women with rheumatoid arthritis: relationship with quadriceps strength

OBJECTIVE

To examine relationships of bone quality as assessed by quantitative ultrasound (QUS) and bone mineral density (BMD, g/cm(2)) with quadriceps strength (QS) in women with rheumatoid arthritis (RA).

METHODS

Sixty seven women with RA according to the 1987 American College of Rheumatology (ACR) criteria were examined. Mean (SD) age was 62 (13) years, mean disease duration 15 years. Most were or had been receiving glucocorticoid treatment. Calcaneal bone quality expressed as speed of sound (SOS, m/s), broadband ultrasound attenuation (BUA, dB/MHz), and stiffness was measured by QUS. BMD of the femoral neck, spine, and distal forearm was measured by dual energy x ray absorptiometry (DXA). Maximal voluntary isokinetic quadriceps strength (Nm) was assessed by isokinetic dynamometry. Pain was recorded on a visual analogue scale (VAS), disability was scored by the Stanford Health Assessment Questionnaire (HAQ), and the degree of physical impairment was expressed by the Steinbrocker index (SI).

RESULTS

In multiple regression analyses, QS predicted SOS, BUA, and stiffness (r(partial) ranging from 0.36 to 0.45, p<0.005) and femoral neck BMD (r(partial)=0.30, p<0.05) independently of age, height, weight, disease duration, HAQ, VAS, SI, and cumulative steroid dose. BMD of the spine and distal forearm was not associated with QS. After adjustment for covariates, women with subnormal BMD of the femoral neck (T score <-1), had a 20% lower QS than those with normal BMD (p<0.0001).

CONCLUSIONS

Calcaneal bone quality and femoral neck BMD were associated with QS in women with RA. This finding indicates that physical activity including muscle strengthening exercises may play a part in the prevention of bone loss in these patients.

Bone mineral density in women and men with early rheumatoid arthritis

OBJECTIVE

To study bone mineral density (BMD) in patients with early rheumatoid arthritis.

METHODS

Dual x-ray absorptiometry was performed in 227 patients, 149 women and 78 men, with rheumatoid arthritis (RA) of no more than 12 months duration.

RESULTS

Women, as well as men above 60 years of age, had a BMD at spine and hip comparable with age and sex matched reference populations. Men younger than 60 years had a tendency to lower BMD. Although the proportion of female patients with osteoporosis was not higher than in the reference, population the proportion of patients with reduced bone mass was increased, and this was found also in men. There was no significant association between BMD and disease duration, disease activity or disability.

CONCLUSION

Untreated patients with early RA have a BMD in spine and hip not significantly different from that of normal reference populations. However, an increased number of the patients had reduced bone mass already at disease onset.

Bone changes in early rheumatoid arthritis

Bone disease in rheumatoid arthritis affects the peri-articular and axial skeleton and is a major cause of disability. Recent studies have shown that pro-inflammatory cytokines stimulate the expression of osteoprotegerin ligand, a transmembrane protein of the tumour necrosis factor ligand superfamily, on synoviocytes and activated T cells. Osteoprotegerin ligand stimulates osteoclast formation and activation, membrane-bound and soluble osteoprotegerin ligand leading to osteoporosis as well as erosions. Bone densitometry using dual energy X-ray absorptiometry is an objective and precise method for monitoring this bone disease. Bone loss is more rapid in patients with early rheumatoid arthritis and correlates well with measures of inflammation and function. Data are emerging that monitoring bone loss of the hands in early rheumatoid arthritis could be an outcome measure and a prognostic indicator of future functional disability. Suppressing inflammation effectively and the use of bone active agents can reduce the rate of loss. In animal models, osteoprotegerin-a decoy receptor of osteoprotegerin ligand-blocks osteoporosis and erosions without affecting inflammation. The use of new biological agents could in future effectively prevent and treat rheumatoid bone disease.

A randomized two-year study of the effects of dynamic strength training on muscle strength, disease activity, functional capacity, and bone mineral density in early rheumatoid arthritis

OBJECTIVE

To evaluate the impact of a 2-year program of strength training on muscle strength, bone mineral density (BMD), physical function, joint damage, and disease activity in patients with recent-onset (<2 years) rheumatoid arthritis (RA).

METHODS

In this prospective trial, 70 RA patients were randomly assigned to perform either strength training (all major muscle groups of the lower and upper extremities and trunk, with loads of 50-70% of repetition maximum) or range of motion exercises (without resistance) twice a week; all were encouraged to engage in recreational activities 2-3 times a week. All patients completed training diaries (evaluated bi-monthly) and were examined at 6-month intervals. All were treated with medications to achieve disease remission. Maximum strength of the knee extensors, trunk flexors and extensors, and grip strength was measured with dynamometers. BMD was measured at the femoral neck and lumbar spine by dual x-ray densitometry. Disease activity was determined by the Disease Activity Score, the extent of joint damage by the Larsen score, and functional capacity by the Health Assessment Questionnaire (HAQ); walking speed was also measured.

RESULTS

Sixty-two patients (31 per group) completed the study. Strength training compliance averaged 1.4-1.5 times/week. The maximum strength of all muscle groups examined increased significantly (19-59%) in the strength-training group, with statistically significant improvements in clinical disease activity parameters, HAQ scores, and walking speed. While muscle strength, disease activity parameters, and physical function also improved significantly in the control group, the changes were not as great as those in the strength-training group. BMD in the femoral neck and spine increased by a mean +/- SD of 0.51 +/- 1.64% and by 1.17 +/- 5.34%, respectively, in the strength-training group, but decreased by 0.70 +/- 2.25% and 0.91 +/- 4.07% in the controls. Femoral neck BMD in the 17 patients with high initial disease activity (and subsequent use of oral glucocorticoids) remained constantly at a statistically significantly lower level than that in the other 45 patients.

CONCLUSION

Regular dynamic strength training combined with endurance-type physical activities improves muscle strength and physical function, but not BMD, in patients with early RA, without detrimental effects on disease activity.

Prospective X-ray densitometry and ultrasonography study of the hand bones of patients with rheumatoid arthritis of recent onset

OBJECTIVE

Bone demineralization observed in early rheumatoid arthritis is not easily measured. To measure bone loss and to discriminate between rheumatoid arthritis and other rheumatic diseases, we used two methods: dual-energy X-ray absorptiometry and ultrasonography.

METHODS

From a population-based recruitment, 32 patients with early peripheral polyarthritis (median disease duration: 4 months) were studied. Clinical, laboratory, functional, hand-bone assessments were made at the entry an at months 6 and 12. Bone X-ray densitometry measurements were made on 16 areas of the hand. Speed of sound was measured across the proximal phalanges of the four fingers. X-rays of both hands were scored according to the modified Sharp's score. At 12 months, patients were classified as rheumatoid arthritis (N = 15; 9 F) or as other rheumatic diseases.

RESULTS

We found: 1) significantly decreased bone mineral density (BMD) of the whole hand, in the rheumatoid arthritis group versus the other rheumatic diseases group, at 6 and 12 months (P < 0.05); 2) no significant decrease of bone mineral density (BMD) in other areas in the rheumatoid arthritis group; 3) no significant change of ultrasounds in either group; and 4) no significant correlation between the decrease of BMD in the rheumatoid arthritis group and clinical, biological or radiologic parameters, except for IFNgamma, whose production in whole blood cell culture was lower at entry in the rheumatoid arthritis group.

CONCLUSION

DEXA bone assessment in rheumatoid arthritis was able t detect bone loss in the whole hand at 6 months.

Pathogenesis of bone erosions in rheumatoid arthritis

Patients with rheumatoid arthritis are at risk for the development of a generalized form of bone loss affecting the axial and appendicular skeleton. In addition, juxta-articular osteopenia and focal erosion of marginal and subchondral bone are commonly seen. The pathogenesis of focal bone erosions is an area of active investigation. Studies of tissue sections from sites of bone erosion in rheumatoid arthritis and in animal models of inflammatory arthritis have identified multinucleated cells with the phenotype of osteoclasts in bone resorption lacunae in these sites, suggesting that osteoclasts mediate a component of this pathologic bone loss. Numerous soluble and cell-membrane factors produced by rheumatoid synovial tissues are likely to play a role in the initiation and progression of bone erosions. In addition, recent studies suggest a role for T lymphocytes and their products in osteoclast-mediated bone loss. This paper reviews the cellular mechanisms and factors implicated in bone erosions in rheumatoid arthritis, and discusses the possible therapeutic strategies suggested by these findings.

Mechanisms of bone loss in inflammatory arthritis: diagnosis and therapeutic implications

Rheumatoid arthritis represents an excellent model in which to gain insights into the local and systemic effects of joint inflammation on skeletal tissues. Three forms of bone disease have been described in rheumatoid arthritis. These include: focal bone loss affecting the immediate subchondral bone and bone at the joint margins; periarticular osteopenia adjacent to inflamed joints; and generalized osteoporosis involving the axial and appendicular skeleton. Although these three forms of bone loss have several features in common, careful histomorphometric and histopathological analysis of bone tissues from different skeletal sites, as well as the use of urinary and serum biochemical markers of bone remodeling, provide compelling evidence that different mechanisms are involved in their pathogenesis. An understanding of these distinct pathological forms of bone loss has relevance not only with respect to gaining insights into the different pathological mechanisms, but also for developing specific and effective strategies for preventing the different forms of bone loss in rheumatoid arthritis.

Secondary osteoporosis. Diagnostic considerations

This article discusses the important secondary causes of osteoporosis that contribute significantly to bone loss and that seem to increase fracture risk, including hypogonadism, endogenous and exogenous thyroxine excess, hyperparathyroidism, malignancies, gastrointestinal diseases, medications, vices, and connective tissue diseases.

Abnormalities in skeletal growth in children with juvenile rheumatoid arthritis

A review of the acquisition of peak skeletal mass in normal children and studies that have been reported for children with JRA lead to the following tentative conclusions: (1) The appendicular skeleton is predominantly the overall status of skeletal mineralization; (2) a failure to develop adequate bone mineralization is virtually universal in children with JRA and is characterized by a failure of bone formation. A failure to undergo the normal increase in bone mass during puberty is common in children with JRA and markedly decreases their potential to achieve an adequate peak skeletal mass; (3) the onset of accelerated skeletal maturation with puberty is a critical period of potential intervention in JRA. Conversely, therapeutic interventions later during adolescence offer less promise of reversal of inadequate bone mineralization; and (4) the most important therapeutic maneuver is likely to be control of the inflammation process, although there is hope, at present unsubstantiated, that supplemental dietary calcium and vitamin D, and normalization of physical activity, many lead to some "catch-up" mineralization.

Bone loss of the radius in rheumatoid arthritis. Comparison between 34 patients and 40 controls

We measured bone mineral density (BMD) in the radius by dual energy X-ray absorptiometry in 34 patients with rheumatoid arthritis (RA) and in 40 healthy controls. The BMD in RA patients in their fifties and sixties, but not in their forties and seventies, was significantly lower than that in the control subjects. The decrease in total radial BMD correlated with grip strength, RA activity and RA stage. The decrease in distal radial BMD correlated with RA activity, but not with grip strength. The levels of serum parathyroid hormone, alkaline phosphatase, and urinary hydroxyproline/creatinine were significantly higher in the patients. From these findings, we suggest that the bone loss in RA patients is affected by severity of inflammation, disuse, postmenopausal osteoporosis and secondary hyperparathyroidism.

Measurement of bone mineral density by dual-energy x-ray absorptiometry in patients with the Wisconsin hip, an uncemented femoral stem

Although qualitative evidence of femoral bone remodeling, secondary to total hip arthroplasty (THA), is apparent on radiographs, quantification of change in bone mass from radiographs is limited. Dual-energy x-ray absorptiometry overcomes many of the limitations and yields accurate and precise bone mineral density (BMD) data. In this study, regional changes in femoral BMD were examined in 89 THA patients with a 2-year follow-up period. Thirty-two patients were evaluated initially before surgery and followed through the first 2 postoperative years. A second group was comprised of 57 patients whose surgery had been performed 1 to 6 years prior to entry into the study; they were also followed for 2 years hence. Thus, both immediate and later bone responses were evaluated prospectively. Maximal bone remodeling was seen in the first 6 months after THA and with a near plateau by the end of the first year. A slow yearly decline in BMD appeared to occur as long as 8 years after THA, thus demonstrating the long-term effects of the introduction of a femoral stem. Variance in preoperative BMD was explained by disease only; no other factors (age, weight, sex) showed significant associations, and body weight was the only variable that affected rate of remodeling after THA (not age, weight, sex, prosthesis size, nor disease). All patients were healthy, relatively young individuals who were good candidates for uncemented implantation, and none showed evidence of clinical complications or surgical failure. It is therefore suggested that the patterns and results reported here be viewed as normative data, that is, the typical skeletal adaptation to THA. In future application, observation of disparate BMD results as compared with these "normal" data may be predictive of abnormal response to surgery and potential for later problems.

Bone loss in rheumatoid arthritis. Influence of disease activity, duration of the disease, functional capacity, and corticosteroid treatment

Axial and appendicular bone mass were studied in 95 patients with rheumatoid arthritis. The aims were to quantify bone mineral density (BMD) and to evaluate the importance of disease activity, duration of disease, functional capacity, and corticosteroid treatment for bone loss in patients with rheumatoid arthritis. The BMD in the lumbar spine (BMDSPINE) did not differ from age-matched healthy controls, but distal forearm BMD (BMDARM) and metacarpal BMD (BMDMCB) were significantly lower in the patients (p < 0.01 and p < 0.001, respectively). Neither BMDSPINE nor BMDMCB were related to the disease activity at the time of investigation. By contrast, BMDARM was decreased in patients with active disease. BMD in any of the three measured locations was not directly correlated to duration of the disease. However, the bone mass in the appendicular skeleton was already decreased within the first two years after the start of the disease. The overall functional capacity in terms of physical activity increased BMD in the axial skeleton. The local functional capacity in terms of grip strength was positively related to BMD in the appendicular skeleton. Patients with severe functional impairment had the lowest BMDARM. The decreased BMD in patients with rheumatoid arthritis seems primarily to be caused by an impaired physical activity which may be related to disease activity. Corticosteroids did not decrease BMD in neither the axial nor the appendicular skeleton. The antiinflammatory effect of steroids lead to clinical improvement, which may counteract the expected negative effect of these drugs on bone in rheumatoid arthritis.

Prevalence of metacarpal osteopenia in young rheumatoid arthritis patients

The aim of this study was to assess the prevalence of and diagnostic role of metacarpal osteopenia in rheumatoid arthritis (RA) and to evaluate its detectability using receiver operating characteristic (ROC) analysis. Metacarpal bone mineral density was measured in 98 patients with classical RA using a computer-assisted measure of 6 metacarpal diameters (radiogrammetry) in patients aged less than 50 years. Sensitivity and specificity of the technique in discriminating the RA patients from 85 normal controls and osteopenic RA subjects from their normopenic counterparts, was determined by standard statistical techniques. Clinical, laboratory and radiological variables were compared in their ability to explain the variance of metacarpal bone density. The prevalence of metacarpal osteopenia in RA was 55%. Prolonged disease and reduced function significantly differentiated osteopenic from non-osteopenic RA patients. Discriminant analysis of RA and control groups showed that measurement of 6 metacarpals was more accurate than the 2nd metacarpal measurement alone in predicting the RA patients. The sum of 6 metacarpal combined cortical width (CCW) had a sensitivity of 61% and specificity of 68% in discriminating the RA patients from the controls. Receiver operating characteristics curves showed, not surprisingly, that objective measurement of bone diameters was superior to clinical or laboratory measures of disease activity in correctly classifying a randomly chosen RA patient as osteopenic or not. Metacarpal osteopenia is common in RA and it may be a useful measure of the disease in young patients.

Bone mineral metabolism in children with juvenile rheumatoid arthritis

Osteopenia has emerged as a major determinant of the outcome of children with juvenile rheumatoid arthritis. Although vertebral compression fractures and fractures of long bones were recognized historically as important clinical developments in the course of disease, a decrease in skeletal mass could only be quantitated and documented early in disease by the recent introduction of bone absorptiometry. This article is limited to recent data from studies on osteopenia in juvenile rheumatoid arthritis and suggests directions of future research that have relevance to current unanswered questions in prevention or management.

Risk of vertebral fracture and relationship to bone mineral density in steroid treated rheumatoid arthritis

OBJECTIVES

To determine the prevalence of vertebral fracture in postmenopausal women with steroid treated rheumatoid arthritis (RA), and whether the risk of vertebral fracture could be predicted from measurements of bone mineral density (BMD).

METHODS

Vertebral deformities were defined from spine radiographs in 76 postmenopausal women with steroid treated RA (aged 50-79 years) and 347 age matched women from a population based group, using a morphometric technique. Lumbar spine (LS) BMD was measured by dual energy x ray absorptiometry.

RESULTS

The odds ratio for vertebral fracture in the women with RA was 6.2 (95% confidence interval 3.2 to 12.3). The decrease in LS-BMD was less than expected for the observed prevalence of vertebral fracture and, among the women with RA, LS-BMD was not lower in those with vertebral fractures.

CONCLUSIONS

We conclude that patients with steroid treated RA may have abnormal bone quality, and that LS-BMD cannot be used to predict the risk of vertebral fracture in these patients.

Osteoporosis in rheumatoid arthritis: effect of disease activity

In addition to juxtaarticular osteoporosis, which appears to reflect predominantly local disease mechanisms, more generalized bone loss can occur in rheumatoid arthritis (RA). The aim of this study was to compare bone mineral density (BMD) of the lumbar spine and proximal femur in RA patients versus controls and evaluate the influence of disease related determinants. Twenty-seven patients with RA and twenty healthy subjects were included in this study. BMD was significantly reduced in RA patients compared with the control group. BMD was correlated with duration of disease, health assessment questionnaire scores, hand grip strength and erythrocyte sedimentation rate. These results support the hypothesis that BMD may be affected by RA related determinants.

Rheumatoid arthritis and bone mineral density in elderly women. The Study of Osteoporotic Fractures Research Group

Previous studies have suggested that women with rheumatoid arthritis (RA) have decreased bone mineral density (BMD) in both the appendicular and axial skeleton. The purpose of this investigation was to determine the association of RA and BMD from a community-based sample of ambulatory Caucasian women age 65 and over. BMD was measured by dual-energy X-ray absorptiometry (DXA) at the hip and lumbar spine and by single photon absorptiometry (SPA) at the distal radius and calcaneus. Study subjects included 120 postmenopausal women with RA who were further classified according to corticosteroid use, i.e., never users, current users, and ex-users, and 7966 age-similar controls. Elderly women with RA had a lower age-adjusted bone density of the distal radius, calcaneus, hip, and lumbar spine. Women with RA who were current users of steroids had the lowest BMD at both appendicular sites and at the hip, but those who never used steroids also had a significantly decreased BMD at all sites. The BMD of women with RA who had never used steroids remained significantly decreased at the distal radius, calcaneus, and hip after adjustment for age, BMD determinants, and functional outcomes of RA. Functional outcomes of RA largely accounted for the lower BMD of women who were currently using steroids. Women with RA have lower appendicular and axial bone mass that is not attributable to the use of steroids. Those currently taking steroids have even lower appendicular and axial bone mass that may reflect their poorer functional outcome and is likely to increase the risk of fractures.(ABSTRACT TRUNCATED AT 250 WORDS)

Rheumatoid arthritis, corticosteroid therapy and hip fracture

OBJECTIVE

To identify the risk of hip fracture in patients with rheumatoid arthritis and those taking corticosteroids.

METHODS

In a population based case-control study, we compared 300 consecutive patients with hip fracture aged 50 years and over from a defined district and 600 age and sex matched community controls.

RESULTS

The risk of hip fracture was increased in patients with rheumatoid arthritis (odds ratio (OR) 2.1; 95% confidence interval (CI) 1.0 to 4.7) and those receiving corticosteroids (OR 2.7; 95% CI 1.2 to 5.8). The risk attributable to rheumatoid arthritis was markedly reduced by adjusting for functional impairment, while that for steroid use remained after adjusting for body mass index, smoking, alcohol, and functional status.

CONCLUSIONS

Hip fracture risk is approximately doubled amongst patients with rheumatoid arthritis and among those taking steroids. These risk increases are, to some extent, independent of each other. In rheumatoid arthritis, the risk was most closely associated with functional impairment, whereas steroid use did not appear to be confounded by this variable.

Measurement of hand bone mineral content by dual energy x-ray absorptiometry: development of the method, and its application in normal volunteers and in patients with rheumatoid arthritis

OBJECTIVES--To develop a method of measuring hand bone mineral content (BMC) by dual energy x ray absorptiometry (DXA); to apply this method of measuring hand BMC to normal volunteers to ascertain causes of variability; and to measure hand BMC in patients with rheumatoid arthritis (RA) of varying duration and severity. METHODS--The x ray beam of the Hologic QDR 1000 dual energy x ray absorptiometer was hardened by introducing a perspex-aluminium plate and the analysis software altered to allow for the small tissue bulk of the hand compared with the torso. Ninety five volunteers (46 men age 24-81 and 49 women age 20-83) had scans of both hands. Eight volunteers were assessed repeatedly to establish reproducibility and effect of hand position. Fifty six patients (22 men, 34 women, age range 25-86 years) with RA of differing duration and severity, had hand BMC measurement by DXA. RESULTS--The precision of BMC measurement was 2.3% with no additional variation due to hand position. Hand dominance had no significant effect on BMC. In men, hand BMC correlated with height (r = 0.57, p < 0.0001), weight (r = 0.58, p < 0.0001), forearm span (r = 0.5, p = 0.0006) and hand volume (r = 0.66, p < 0.0001). In women hand BMC correlated with height (r = 0.66, p < 0.0001), weight (r = 0.4, p = 0.003), forearm span (r = 0.3, p = 0.03) and hand volume (r = 0.49, p = 0.0008). After correcting for all these variables, male volunteers had significantly higher hand BMC than female volunteers (p = 0.01) and patients with RA had lower hand BMC than normal volunteers (total hand BMC in male volunteers 90.9 gms, 95% CI 86.9-95, in male patients 81.7 gms, 95% CI 73.7-89.6, p < 0.004, total hand BMC in female volunteers 62.2 gms 95% CI 59.8-64.5, female patients 52.3 gms, 95% CI 48.1-56.5, p < 0.005). In patients with RA, the hand BMC showed an inverse correlation with age (r = -0.44, p = 0.01), disease duration (r = -0.62, p = 0.0003), Larsen's grades (r = -0.62, p = 0.0002) and modified Sharp's method score (r = -0.69, p < 0.0001) in female patients only. CONCLUSIONS--A new, sensitive and reproducible technique of measurement of hand bone mineral content by DXA, has been developed and this method has been applied to normal volunteers and patients with RA. Hand dominance had no significant effect on hand BMC. After correcting for physical size, men have higher hand BMC than women. Hand BMC inversely correlates in women patients with disease duration and other validated methods of assessing radiological outcome in RA. Longitudinal studies are needed to establish its role in monitoring disease progression.

Bone mineral density in nonsteroid treated early rheumatoid arthritis

OBJECTIVES

To determine whether significant reduction in bone mass is detectable in early disease in patients with rheumatoid arthritis (RA) and to examine the possible influences of disease activity and physical disability on bone mineral density (BMD) of the lumbar spine (LS) and femoral neck (FN).

METHODS

LS and FN BMD values were measured and Z scores determined in a cross-sectional study of 104 patients with RA of less than five years duration. BMD values were also compared between a subgroup of 64 patients and a normal control group matched for age, sex, menopausal status and body mass. BMD values and Z scores were correlated with disease activity, measured by the Stoke Index, disability, measured by HAQ score, and disease duration.

RESULTS

Premenopausal female patients with RA had significantly reduced mean FN Z scores (-0.62, 95% CI -0.30 to -0.94) which correlated with HAQ scores (Rs 0.358, p = 0.05) and age (Rs 0.397, p = 0.03). There were no significant changes of BMD in males or postmenopausal females. Disease duration and disease activity did not correlate with BMD changes.

CONCLUSION

BMD is reduced in premenopausal female patients with early RA possibly related to the attainment of peak bone mass. No significant reduction of BMD was found in males or postmenopausal females with early disease. Physical disability but not disease activity appears to play a role in the reduction of FN bone mass.

Bone mineral density of the hand in rheumatoid arthritis

OBJECTIVE

To determine the reproducibility, accuracy, and linearity of hand bone mineral content (BMC) measurements, and to evaluate the influence of hand posture; to determine the relationship of hand bone mineral density (BMD) to generalized osteopenia in rheumatoid arthritis (RA); and to determine the relationship between hand BMD and disease severity in early RA.

METHODS

Hand BMD was measured by dual-energy x-ray absorptiometry (DXA). We studied 70 postmenopausal women with steroid-treated RA (established RA), ages 49-79, and 20 age-matched healthy controls to determine the relationship to generalized osteoporosis; we also studied 20 patients aged 23-74 years with early RA to determine the relationship between disease severity and hand BMD.

RESULTS

Reproducibility of hand BMD was to within 1%. In established RA, there was a greater decrease in juxtaarticular BMD (23% at the hand) than in generalized BMD (16% at the femoral neck, 11% at the lumbar spine, and 11% total body) compared with that in age-matched controls. Hand BMD correlated with skeletal size and BMD at other skeletal sites. In established RA, there was no effect of disease duration, disability, or steroid therapy. In early RA, hand BMD correlated with age and disease activity.

CONCLUSION

Measurement of hand BMD by DXA is accurate and precise. Hand BMD reflects BMD at other skeletal sites in patients with RA, and is a marker of disease severity in patients with early disease. It may be a sensitive marker of disease progression and response to therapeutic intervention.

Vitamin D metabolism and bone mineralization in children with juvenile rheumatoid arthritis

OBJECTIVE

To examine bone mineralization and bone mineral content in a cross-sectional population of children with juvenile rheumatoid arthritis (JRA).

METHODS

Bone mineral content was measured by single-photon absorptiometry in 44 children with JRA and 37 control children. Serum concentrations of minerals, vitamin D, parathyroid hormone, osteocalcin, bone alkaline phosphatase, and tartrate-resistant acid phosphatase, and urinary concentrations of minerals, were determined.

RESULTS

Bone mineral content was decreased in children with JRA. Significantly lower concentrations of osteocalcin (7.4 +/- 3.4 vs 12.5 +/- 2.5 micrograms/L) and bone alkaline phosphatase (78.8 +/- 36.4 vs 123.0 +/- 46.0 IU/L) suggested reduced bone formation; lower levels of tartrate-resistant acid phosphatase (10.3 +/- 4.1 vs 14.4 +/- 5.8 IU/L) and a lower urinary calcium/creatinine ratio (0.07 +/- 0.06 vs 0.12 +/- 0.09) suggested decreased bone resorption. The serum calcium concentration was significantly lower (9.3 +/- 1.0 vs 10.0 +/- 0.4 mg/dl), as was the parathyroid hormone concentration (19.8 +/- 8.6 vs 26.7 +/- 9.3 ng/L); 1,25-dihydroxyvitamin D values (30.1 +/- 10.5 vs 30.4 +/- 9.3 pg/ml) were normal.

CONCLUSION

These data suggest that decreased mineralization in JRA is related to low bone turnover; parathyroid hormone and 1,25-dihydroxyvitamin D levels may be inappropriately normal for the decreased serum calcium concentration in children with JRA.

Decreased axial bone mineral density in perimenopausal women with rheumatoid arthritis--a population based study

OBJECTIVES

Although periarticular osteoporosis is a well-recognised phenomenon in rheumatoid arthritis (RA), there is considerable controversy over whether RA is associated with more generalised osteoporosis. The aetiology of this bone loss is probably multifactorial, including both life-style risk factors and disease-related determinants. Population-based studies on bone mineral density (BMD) in RA have not previously been conducted, and the purpose of the present cross-sectional population-based study was to determine whether patients with RA are at an increased risk of having osteoporosis. Furthermore, the determinants of BMD in RA patients were investigated.

METHODS

BMD at the spine and femoral neck was measured in 143 women with RA. The control group consisted of 1611 women with no disease or taking any drugs known to affect bone metabolism. The study population was a random stratified sample from the Kuopio Osteoporosis Study, which included all perimenopausal women aged 47-56 years residing in Kuopio Province, Eastern Finland in 1989 (n = 14,220). The mean age of the patients at the time of densitometry was 53.7 years.

RESULTS

The mean (SD) spinal and femoral neck BMD was significantly lower in patients with RA compared with controls [spine: 1.067 (0.161) v 1.129 (0.157) g/cm2, p < 0.001; femoral neck: 0.851 (0.136) v 0.932 (0.123) g/cm2, p < 0.001]. Analysis of variance showed that at the spine the difference was significant only in patients having corticosteroid treatment, whereas at the femoral neck patients with non-steroid treatment also had significantly lower BMD. When confounding factors were corrected, no significant difference could be found between non-steroid and corticosteroid treated patients with RA, suggesting that the independent effect of corticosteroids on BMD is only minimal. Multiple regression analysis found age, weight and functional grade to be significant predictors of spinal BMD (R2 = 0.403, p < 0.001). In the femoral neck weight, cumulative corticosteroid dose and functional grade were significant predictors of BMD (R2 = 0.410, p < 0.001).

CONCLUSIONS

RA is associated with generalised osteoporosis. The physical impairment and body weight are the major determinants of both spinal and femoral bone mass in RA patients. The cumulative corticosteroid dose was also a significant determinant of femoral neck BMD. However, the independent effect of corticosteroids is questionable because the use of corticosteroids may be an indicator of more severe disease.

Loss of trabecular bone mineral density in systemic lupus erythematosus

OBJECTIVE

To evaluate trabecular bone mineral density (BMD) in young ambulatory female patients with systemic lupus erythematosus (SLE).

METHODS

Bone mineral density (gm/cm2) at the lumbar vertebrae (L1-L4) and at the left femur (neck, trochanter, intertrochanter, and Ward's triangle) was measured by dual x-ray absorptiometry in 46 SLE patients (mean age 31 years, mean disease duration 76 months) and in 108 healthy female controls (mean age 32 years). Twenty-two of the SLE patients were receiving corticosteroids (CS) at the time of the study.

RESULTS

Lumbar BMD in the SLE patients was less severely reduced than was BMD at the femoral sites, but the SLE group was closer to the lumbar fracture threshold of 0.812 gm/cm2 than was the control group (P = 0.0009). There were no significant differences between the SLE patients currently being treated with corticosteroids and those who were not (P > 0.3). BMD at Ward's triangle and at the femoral neck was not significantly reduced in the SLE patients. Total femoral BMD had a sensitivity of 76% and specificity of 62% in differentiating the SLE group from the controls. The positive predictive value was 61% and the negative predictive value was 89%. The prevalence of osteopenia in the SLE patients was 25%.

CONCLUSION

SLE causes significant trabecular bone loss, which is not due to corticosteroid therapy.

Application of computer-based histomorphometry to the quantitative analysis of methylprednisolone-treated adjuvant arthritis in rats

Analyses of paw edema and histomorphometry were performed on tibio-talar joints to determine arthritic pathological responses in untreated 28-day adjuvant-induced polyarthritis (AIP) rats, and to determine the drug effect on inhibiting these responses in AIP rats treated with methylprednisolone. Histomorphometric measurements were performed on regions including articular joint space, synovial tissue, articular and epiphyseal cartilage, epiphyseal and metaphyseal bone marrow, and endosteal and periosteal cortical bone surfaces. Analysis of paw edema indicated that paw volume was significantly increased in untreated AIP rats. This increase in paw volume was partially prevented in AIP rats treated with 0.3 mg methylprednisolone/kg per day, and completely prevented in AIP rats treated with the two higher dose levels (1 and 3 mg/kg per day). Histomorphometric analysis of untreated AIP tibio-talar joints showed decreased articular joint space whereas synovial tissue area increased and a minor, but significant, articular cartilage erosion area occurred. Epiphyseal growth cartilage area was decreased. Trabecular bone area in distal tibial epiphyseal and metaphyseal regions was markedly decreased whereas bone marrow area increased involving a large number of macrophages and osteoclasts. Eroded endocortical bone area was increased while cortical bone area decreased. Marked osteophyte proliferation occurred on the periosteal surface. These arthritic pathological changes were inhibited by the treatment of methylprednisolone in a dose-dependent fashion. The animals treated with the highest dose of methylprednisolone complete prevented the development of the AIP-induced pathological changes. These data confirmed qualitative histological evaluation of arthritic changes but did not correlate with the anti-edema effects of methylprednisolone (100% inhibition at 1.0 and 3.0 mg/kg, p.o.). It is suggested that quantitative histomorphometry be used to determine more precisely the AIP rat model and the effects of drugs on different histopathological features in this experimental model of arthritis in preference to paw edema which gives a more limited picture of the arthritic response.

Physical activity as a determinant of bone conservation in the radial diaphysis in rheumatoid arthritis

OBJECTIVES

To determine if increasing physical activity is protective of diaphysial (cortical) bone mass

METHODS

Fifteen patients attending two rheumatology clinics who had developed seropositive or classical rheumatoid arthritis up to 26 months previously were studied prospectively for two to three years. Rates of loss (or gain) in bone mass in the radial diaphysis and the trabecular bone of the distal radius were measured by quantitative computed tomography, and in the spine by dual photon absorptiometry. Physical activity was assessed by the Framingham physical activity index. Disease activity was followed at three-monthly clinic visits at which the haemoglobin, erythrocyte sedimentation rate, and platelet count were measured. The urinary hydroxyproline to creatinine ratio and plasma osteocalcin were measured at the beginning and end of the observation period.

RESULTS

Eleven patients required treatment with disease modifying drugs but none was given corticosteroids. Those whose physical activity did not improve lost radial diaphysial bone at about 4% annually. There was, however, a statistically significant inverse relation, accounting for 48.5% of the variance, between bone loss at this site and improvement in physical activity as assessed by the Framingham index. The other two sites showed much weaker associations. Adjusting for indices of disease activity hardly affected the first relation. Three biochemical indices related to bone turnover showed weak tendencies to decrease with increasing physical activity.

CONCLUSIONS

Peripheral cortical bone, distant from inflamed joints, is conserved more successfully in patients who achieve higher levels of physical rehabilitation. This may have implications for avoiding long bone fractures later in the disease.

Bone mineral density of the hip and of the anteroposterior and lateral dimensions of the spine in men with rheumatoid arthritis. Effects of low-dose corticosteroids

OBJECTIVE

To assess bone mineral density (BMD) in men with steroid-treated rheumatoid arthritis (RA).

METHODS

Dual-energy x-ray absorptiometry (DXA) was used to measure BMD in 40 men with RA, 20 of whom were receiving low-dose corticosteroids (< or = 10 mg prednisolone daily), and in 20 healthy, age-matched male controls.

RESULTS

BMD was significantly reduced at the femoral neck and greater trochanter in both groups of RA patients, and at the spine from the anteroposterior dimension in the steroid-treated group.

CONCLUSION

Low-dose steroid therapy may induce excess axial osteopenia in men with RA.

Bone mineral density in patients with recent onset rheumatoid arthritis: influence of disease activity and functional capacity

BACKGROUND

Generalised osteoporosis is often described in patients with rheumatoid arthritis (RA). The aim of this study was to evaluate disease related determinants of bone mineral density (BMD) in patients with RA.

METHODS

Subjects were selected from a group of 147 patients with recent onset RA. Disease activity and functional capacity were studied prospectively in this cohort. Activity of the disease was assessed once every three months by various parameters, and functional capacity was measured with a health assessment questionnaire once every six months. Ninety seven patients consented to participate in the study. Bone mineral density was assessed with dual energy x ray absorptiometry in the lumbar spine, in a combined region of interest in the hips, and in Ward's triangle. Multiple linear regression procedures were used to analyse the data.

RESULTS

Duration of RA was negatively associated with BMD at all three sites of measurement. The mean erythrocyte sedimentation rate in the six months before BMD measurement was negatively associated with BMD in the hip and in Ward's triangle. Other parameters of disease activity were not related to BMD. The mean health assessment questionnaire score in the 18 months before BMD measurement was negatively associated with BMD in the combined hip region only. Bone mineral density tended to be decreased when patients were compared with a normal reference group, especially in the femoral regions of interest.

CONCLUSIONS

It is concluded that BMD may be affected in patients with recent onset RA by disease dependent mechanisms. Several factors have been suggested elsewhere as determinants of BMD in RA. The results of this study show that disease duration, disease activity, and functional impairment may, independently of each other, contribute to bone loss, especially in the proximal femur.

Metacarpal bone mass in systemic lupus erythematosus

We report the prevalence of metacarpal cortical thinning in systemic lupus erythematosus (SLE). Fifty-eight ambulant female patients attending a lupus clinic (mean age 32.4 years), were found to have significant thinning of metacarpal cortices (p < 0.05) when compared with 63 normal females (mean age 34.1 years). However, metacarpal bone mass was within the normal range. Measurements were made at 6 metacarpals of the 2 hands using a computer-aided technique (digitized radiogrammetry). Femoral cortical width and Singh index at the left femur, as well as the vertebral index at L3 were also recorded. The trabecular indices were in the range of normality, but the SLE group had more patients in the immediately pre-osteopenic range. Metacarpal bone loss was not related to disease duration or corticosteroid therapy. The prevalence of osteopenia in SLE is probably underestimated and the pathogenesis is likely to be multifactorial.

Osteocalcin in patients with rheumatoid arthritis--effect of anatomical stages, inflammatory activity and therapy

The aim of this study was to investigate whether the degree of inflammatory activity, the anatomical stage and various treatments have an influence on bone turnover in patients with rheumatoid arthritis (RA). Osteocalcin (OC) and other parameters of bone turnover were measured in 131 patients with RA. The mean values of alkaline phosphatase (AP), but not of OC were significantly (P < 0.01) higher in our patients compared to controls. In contrast to AP, OC values increased and correlated significantly (r = +0.33, P < 0.01) with ascending anatomical stage in women not on glucocorticoid treatment. As regards therapy, we found significantly lower OC levels in women receiving steroids compared to controls (P < 0.03) and those being treated with non-steroidal anti-inflammatory drugs (NSAIDs) (P < 0.03), methotrexate (MTX) (P < 0.05), or gold (P < 0.01). Females treated with gold had higher OC levels than patients receiving no antirheumatic drugs (P < 0.03). Furthermore, there was a significantly negative correlation between OC and inflammatory activity [C-reactive protein (CRP)] (r = -0.25, P < 0.003). In conclusion, OC levels were significantly higher (P < 0.032) in patients with advanced (anatomical) stages of RA. In contrast to AP, changes in bone turnover, such as suppression of bone formation by steroids and high inflammatory activity in patients with RA, were easily detected.

Effect of calcitonin on bone histomorphometry and bone metabolism in rheumatoid arthritis

Twenty-four women (mean age +/- SD 49 +/- 13 years) with classical or definite rheumatoid arthritis (disease duration 15 +/- 8 years) were treated with synthetic salmon calcitonin (SCT) nasal spray 200 IU three times a week for 3 months. Bone biopsies from the iliac crest were taken before and after SCT treatment. Histomorphometrical quantification of undecalcified bone sections was made using the manual point-counting method. SCT decreased the resorption surface of trabecular bone (ES/BS) significantly (P less than 0.001). There was also a significant increase (P less than 0.05) in trabecular bone volume (BV/TV) after 3 months of treatment, whereas no statistically significant changes were found in osteoid parameters. There were no significant changes in biochemical analyses of bone metabolism. We conclude that SCT might be useful in the prevention of bone loss in RA.

Glucocorticoid-induced osteoporosis: a cross-sectional study

We studied 70 patients (48 women and 22 men) with either rheumatic disease (n = 25) or lung disease (n = 45) who had been treated with glucocorticoids for at least 6 months (mean cumulative dose, 24.2 +/- 27.1 g of prednisone; mean current dose, 11.0 +/- 8.6 mg/d, mean duration of therapy, 8.1 years. We measured bone mineral density (BMD) of the hip (femoral neck) and spine (L2-L4) using dual-photon absorptiometry and BMD of the distal one third radius using single-photon absorptiometry. Compared with age-matched controls, the study population had decreased BMD of the spine (87.0%), hip (87.2%), and radius (90.6%). Current dose, cumulative dose, and duration of therapy were not correlated with BMD in the spine or hip in the total study population. The most significant correlations with low bone mass at the hip and spine were short height and low weight. There was a high incidence of hypercalciuria (30%) as compared with an age- and sex-matched control group (6.4%). Glucocorticoids are known to decrease vertebral and radial bone density. We conclude that glucocorticoids also decrease hip bone density as measured at the femoral neck. The high incidence of hypercalciuria may have implications for therapy of glucocorticoid-induced osteoporosis.

Generalized osteoporosis in non-steroid treated rheumatoid arthritis

To investigate the presence of reduced bone mineral density (BMD) and to assess determinants of bone loss in rheumatoid arthritis, 45 female patients suffering from non-steroid treated rheumatoid arthritis were submitted to dual photon absorptiometry of the lumbar spine and to laboratory tests for calcium metabolism. The rheumatoid arthritis patients were divided into two groups according to anatomic grade and functional class; no abnormalities in calcium metabolism were detected whereas BMD was significantly lower in the third and fourth grade and in the third and fourth class patients (P less than 0.005 versus controls, versus grades I and II and versus classes 1 and 2). BMD was significantly correlated with age (P less than 0.001) and years postmenopausal (P less than 0.01), but not with duration of disease. By multiple linear regression we derived an equation predictive of BMD. Osteoporosis in rheumatoid arthritis is observed even in non-corticosteroid treated patients; articular lesions with subsequent reduction in physical activity appear to play an important role in axial bone loss in rheumatoid arthritis.

Abnormalities in serum osteocalcin values in children with chronic rheumatic diseases

We studied bone mineral metabolism prospectively in 113 children with chronic rheumatic diseases (juvenile arthritis, systemic lupus erythematosus, and juvenile dermatomyositis) to determine the relationship of serum levels of osteocalcin to rheumatic disease activity and corticosteroid usage, and to determine, in part, the cause of osteopenia in this population. Disease activity was quantitated by historical, clinical, and serologic means and an activity score derived. The 113 children were divided according to the expression of their disease, which was active (group 1: mean score 3.42, mean erythrocyte sedimentation rate 28 mm/hr) or inactive (group 2: score 1.7, erythrocyte sedimentation rate 15 mm/hr) (p less than 0.02 group 1 vs group 2 for each value), or which remitted during the study (group 3). We found that serum levels of osteocalcin, but not those of ionized calcium, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and parathyroid hormone, were reduced in group 1 children even before corticosteroid therapy was employed. Children in both group 2 and group 3 had normal osteocalcin levels despite the use of corticosteroids. The reduced levels of osteocalcin were predictive of a reduction in bone mass measured by photon absorptiometry in 16 of 19 children so studied. We conclude that skeletal abnormalities that result in a reduced bone mass occur in the clinical course of the majority of children with active chronic rheumatic diseases, are associated with reduced osteocalcin levels, and are not related to the use of corticosteroids. Serum osteocalcin levels may be a sensitive marker for reduced osteoblast activity and bone formation in children with chronic rheumatic diseases.

Osteopenia in rheumatoid arthritis: a biochemical, hormonal and histomorphometric study

To determine whether the osteopenia of rheumatoid arthritis (RA) is due to reduction of trabecular bone mass (TBV) and/or cortical width (CW), we evaluated these parameters by bone histomorphometry; we also measured the calciotropic hormones parathormone(PTH) and calcitonin (CT), vitamin D [25(OH)D] and the biological markers of bone remodeling in a group of patients with RA. Study subjects were divided into Group C - premenopausal patients, and Group A - menopausal patients and men of the same ages. These groups were compared to two age-matched control groups, B and D. In both A vs. B and C vs. D, TBV and CW were significantly lower in patients. There were no differences in PTH or CT, but 25(OH)D was significantly reduced, and BGP, OHP/Cr and AP were raised in patients. Patients also exhibited TBV loss in more than 55% and CW loss in more than 98%. These changes suggest that the decline in bone mass, mainly cortical, but also trabecular, is due to increased bone turnover and enhanced resorption and seem to reflect intrinsic alterations of RA.

Serum osteocalcin as an index of bone turnover in active rheumatoid arthritis and in active psoriatic arthritis

Juxtaarticular osteoporosis is a recognized clinical feature in both rheumatoid arthritis (RA) and psoriatic arthritis (PA), while generalised osteopenia seems to be characteristic of RA only. To assess differences in bone turnover in the two forms of disease, we measured serum osteocalcin levels and other parameters of bone metabolism in two groups of female, ambulant, age-matched patients suffering from active RA or active PA and never treated with steroid therapy. Serum osteocalcin levels were significantly higher in RA patients than in PA patients (13.05 +/- 1.27 ng/ml vs 4.83 +/- 0.88 ng/ml; p less than 0.001), with a significant positive correlation between osteocalcin and serum alkaline phosphatase in both groups. These data suggest that bone turnover is higher in active RA than in active PA. Juxtaarticular osteoporosis could be mediated by local disease mechanisms both in RA and in PA, while factors specifically related to active RA seem to determine a more generalized impairment of bone turnover.