The association between systemic sclerosis and bone mineral density- a meta-analysis of observational studies

Prevalence and effects of Vitamin D receptor polymorphism on bone mineral density and metabolism in patients with systemic sclerosis: a preliminary study

Patients with systemic sclerosis (SSc) have a disproportionately high prevalence of reduced bone mineral density (BMD). Polymorphisms of the vitamin D receptor (VDR) gene have been associated with osteoporosis in patients with autoimmune diseases. The aim of this study was to investigate the prevalence and possible effects of VDR polymorphism on BMD and bone metabolism in patients with SSc. In patients with SSc measurement of BMD was performed using dual-energy X-ray absorptiometry. VDR polymorphisms (FokI, BsmI) were genotyped using restriction fragment length polymorphism analysis. Markers of bone metabolism (calcium, osteocalcin, β-crosslaps) were determined. Primary endpoint was the prevalence of VDR gene polymorphisms and the association with reduced BMD. Secondary endpoints included associations between bone metabolism and VDR gene polymorphism. 79 Caucasian patients with SSc were included. Overall, 83.5% had reduced BMD (51.9% osteopenia, 31.6% osteoporosis). The prevalence of VDR gene polymorphism (73% BsmI, 77% FokI) was comparable to studies in healthy and rheumatic populations. The homozygous presence of FokI polymorphism, but not BsmI, was significantly associated with reduced axial BMD. Fokl polymorphism was significantly associated with reduced CTX levels, although changes remained within the reference limits. VDR polymorphisms can frequently be found in patients with SSc in comparable prevalence to healthy and rheumatic populations. The homozygous presence of FokI polymorphism, but not BsmI, was significantly associated with reduced axial BMD. This could be a possible contributor for the high prevalence of reduced BMD in 83.5% of patients with SSc in this study.Trial registration. DRKS00032768, date: 05.10.2023, retrospectively registered.

Relationship between ectopic calcifications and bone fragility depicted on computed tomography scan in 70 patients with systemic sclerosis

Background

A higher risk of osteoporotic fracture was described in systemic sclerosis patients than in healthy patients.

Objective

To evaluate the relation between osteoporotic fracture risk measured by the scanographic bone attenuation coefficient of the first lumbar vertebra (SBAC-L1) on computed tomography (CT) scan and the presence of ectopic calcifications: vascular, valvular and spinal.

Methods

This monocentric retrospective study was performed on patients followed between 2000 and 2014 at Nancy University Hospital. Systemic sclerosis patients, according to ACR/EULAR 2013 criteria, followed from 2000 to 2014 and who underwent, during their follow-up, a CT including the first lumbar vertebra were included. The SBAC-L1 was measured with a threshold set at 145 Hounsfield units (HU). Vascular and spinal calcifications were studied on CT. For vascular calcifications, the Agatston score was used. Valvular calcifications were studied on echocardiography.

Results

A total of 70 patients were included (mean age: 62.3 (±15.6) years, women 88.5%). The mean SBAC-L1 was 157.26 (±52.1) HU, and 35 patients (50%) presented an SBAC-L1 ⩽ 145 HU. The reproducibility of the calcification evaluation was good, with kappa coefficients varying between 0.63 and 1. In univariate analysis, spinal and vascular calcifications were associated with an SBAC-L1 ⩽ 145 HU, with ORs of 13.6 (1.6-113.3) and 8 (95%CI: 2.5-25.5), respectively. In multivariate analysis, the SBAC-L1 was not associated with the presence of any ectopic calcifications. The SBAC-L1 decreased with age (p = 0.0001).

Conclusion

Patients with systemic sclerosis with an SBAC-L1 ⩽ 145 HU were older, but they did not have more ectopic calcification.

Trial registration

The ethics committee of Nancy Hospital agreed with this study (referral file number 166). This study was designed in accordance with the general ethical principles outlined in the Declaration of Helsinki.

A meta-analysis of fracture risk and bone mineral density in patients with systemic sclerosis

INTRODUCTION

Osteoporosis and fractures are important public health issues that impose serious burdens on patients. Patients with systemic sclerosis (SSc) have low bone mineral density (BMD) and increased risk for fracture. We aimed to explore the association between SSc and BMD and fracture risk.

METHODS

For this meta-analysis, we analyzed data from articles that reported mean differences in BMD or fracture risk between patients with SSc and controls. We undertook a systematic literature search of the PubMed, Web of Science, and Cochrane Library databases. The pooled weighted mean difference (WMD) was used to estimate the mean difference in BMD between patients with SSc and controls. Pooled odds ratios (ORs; with 95% confidence intervals [95% CIs]) were used to assess the association between SSc and fracture risk.

RESULTS

Analysis of the results from 18 studies showed that patients with SSc had significantly lower BMD than controls in the following categories: whole body (WMD - 0.07, 95% CI - 0.1 to - 0.04, p < 0.00001), lumbar spine (WMD - 0.08, 95% CI - 0.11 to - 0.05, p < 0.00001), femoral neck (WMD: -0.28, 95% CI: -0.46 to -0.10, p=0.002), total hip (WMD - 0.10, 95% CI - 0.14 to - 0.06, p < 0.00001), and femoral trochanter (WMD - 0.06, 95% CI - 0.09 to - 0.03, p < 0.0001). Moreover, patients with SSc had an increased risk of vertebral fracture (OR 10.38, 95% CI 1.19 to 90.58, p = 0.03). We did not find a significant difference in the risk of osteoporotic fracture between patients with SSc and controls (OR = 2.24, 95% CI 0.58 to 8.59, p = 0.24).

CONCLUSION

Patients with SSc have a significant reduction in bone mass, and these patients have an increased risk of vertebral fracture. The early monitoring of BMD in patients with SSc is recommended for the prevention of osteoporosis and fracture.Key points• SSc patients have a significant low BMD• SSc patients also have an increased risk of vertebral fracture.

Imaging in osteoporosis in rheumatic diseases

Osteoporosis is a common comorbidity of all major rheumatic diseases, and manifests itself both systemically and locally. Systemic bone loss manifests because of several factors, primarily inflammation, immobility, and commonly used medical treatment for rheumatic diseases. Local bone loss manifests as periarticular demineralization and bone erosion due to local release of inflammatory agents and cytokines, which promote bone resorption. All these factors contribute to the phenomenon of arthritis-associated osteoporosis. This review summarized the currently available and used methods that play a role in the diagnosis and monitoring of osteoporosis and in the detection of osteoporotic fractures.

Bone Metabolism in a Large Cohort of Patients with Systemic Sclerosis

The aim of this study was to evaluate in a large size cohort of SSc patients bone mineral density (BMD) and to analyze its possible determinants. 106 consecutive outpatients affected by SSc were enrolled and completely evaluated for bone metabolism and SSc characteristics. For the statistical analysis, we preferred Z score to BMD or T score since the population was composed of patients of different ages and of both sexes. Mean neck Z score was significantly lower than 0. No significant differences were found for other sites. Female patients were shown to have a total femur and neck Z score significantly lower than 0 (p = 0.028 and p < 0.001, respectively). 13 % of patients had at least one morphometric non-clinical vertebral fracture. In univariate analysis, total femur Z score was lower in female (p = 0.050) and positively correlates with BMI (p = 0.001), neck Z score positively correlates with age (p = 0.016), and whole body Z score positively correlates with BMI (p < 0.001). No correlations were found for lumbar Z score. The multivariate analysis confirmed the positive correlation between BMI and total femur and whole body Z score and between age and neck femur Z score (p = 0.005, p < 0.001 and p = 0.040, respectively). Lung involvement was shown to correlate with a lower whole body Z score in multivariate analysis (p = 0.037). We found a modest risk of low BMD in patients with SSc and the important protective role of BMI. Patients with lung involvement showed lower whole body Z score.