Rheumatoid arthritis (RA) patients had a higher risk of developing low bone mineral density (BMD) or osteoporosis. RA patients on classic disease-modifying antirheumatic drug (c-DMARD) therapy showed significantly lower BMD than controls, while no significant differences in most parameters were found between RA patients receiving biological disease-modifying antirheumatic drugs (b-DMARDs) and controls. The 3D analysis allowed us to find changes in the trabecular and cortical compartments.

Introduction: To evaluate cortical and trabecular bone involvement of the hip in RA patients by dual-energy X-ray absorptiometry (DXA) and 3D analysis. The secondary end-point was to evaluate bone involvement in patients treated with classic (c-DMARD) or biological (b-DMARD) disease-modifying antirheumatic drug therapies and the effect of the duration of the disease and corticosteroid therapy on 3D parameters.

Methods: A cross-sectional study of 105 RA patients and 100 subjects as a control group (CG) matched by age, sex, and BMI was carried out. BMD was measured by DXA of the bilateral femoral neck (FN) and total hip (TH). The 3D analyses including trabecular and cortical BMD were performed on hip scans with the 3D-Shaper software.

Results: FN and TH BMD and trabecular and cortical vBMD were significantly lower in RA patients. The c-DMARD (n = 75) group showed significantly lower trabecular and cortical vBMD than the CG. Despite the lower values, the b-DMARD group (n = 30) showed no significant differences in most parameters compared with the CG. The trabecular and cortical 3D parameters were significantly lower in the group with an RA disease duration of 1 to 5 years than in the CG, and the trabecular vBMD was significantly lower in the group with a duration of corticosteroid therapy of 1 to 5 years than in the CG, while no significant differences were found by standard DXA in the same period.

Conclusions: RA patients had a higher risk of developing low BMD or osteoporosis than controls. RA patients receiving c-DMARD therapy showed significantly lower BMD than controls, while no significant differences in most parameters were found between RA patients receiving b-DMARDs and controls. 3D-DXA allowed us to find changes in trabecular and cortical bone compartments in RA patients.

Wnt/β-catenin signaling is important for skeletal development and health. Eleven heterozygous gain-of-function missense mutations within the first β-propeller of low-density lipoprotein receptor-related protein 5 (LRP5) are known to cause the autosomal dominant disorder called high bone mass (HBM). In 2019, different heterozygous LRP6 missense mutations were identified in two American families with the HBM phenotype but including absent lateral maxillary and mandibular incisors. We report a 19-year-old Argentinian man referred for «osteopetrosis» and nine years of generalized, medium-intensity bone pain and arthralgias of both knees. His jaw and nasal bridge were broad and several teeth were missing. Routine biochemical testing, including of mineral homeostasis, was normal. Urinary deoxypyridinoline and serum CTX were slightly increased. Radiographic skeletal survey showed diffusely increased radiodensity. DXA revealed substantially elevated BMD Z-scores. Digital orthopantomography confirmed agenesis of his maxillary and mandibular lateral incisors and his second left superior premolar. Cranial magnetic resonance imaging showed diffuse thickening of the calvarium and skull base, dilation of the sheath of the optic nerves containing increased fluid and associated with subtle stenosis of the optic canal, and narrow internal auditory canals. Mutation analyses identified a heterozygous indel mutation in exon 4 of LRP6 involving a single nucleotide change and 6-nucleotide deletion (c.678T>Adel679-684, p.His226Gln-del227-228ProPhe) leading to a missense change and 2-amino acid deletion that would compromise the first β-propeller of LRP6. Experience to date indicates LRP6 HBM is indistinguishable from LRP5 HBM without mutation analysis, although in LRP6 HBM absence of adult lateral incisors may prove to be a unique feature.

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disease that leads to joint deformity and disability, as well as muscle involvement. Sarcopenia is characterized by a progressive age-related loss of muscle mass and strength.

Aim: The aim of this study was to evaluate the prevalence of sarcopenia and possible contributing factors associated with sarcopenia in RA patients.

Patients and methods: Adult RA patients (n = 105) of both sexes and 100 subjects as control group (CG) matched by age, sex, and body mass index were included in this cross-sectional study. Whole-body composition was measured by dual-energy x-ray absorptiometry. Sarcopenia was defined according to European Working Group on Sarcopenia in Older People 2 as low muscle strength (handgrip) and low muscle mass (appendicular skeletal muscle mass [ASM] index by dual-energy x-ray absorptiometry). The association between sarcopenia and associated factors was evaluated using logistic regression analyses.

Results: Significantly lower percentage of lean mass and ASM were found in the whole RA group compared with controls. However, lower lean parameters (total lean mass, percentage of lean mass, and ASM) were observed only in female subjects. The ASM index was significantly lower in female subjects with RA (RA 31.0% vs CG 11.9%) without differences in male subjects. On the other hand, fat mass and most adipose indices were significantly higher in both female and male subjects with RA. Female RA patients had higher prevalence of sarcopenia and sarcopenic obesity. Through univariate logistic regression analysis, the time of corticoids use, cumulative corticosteroid dose, previous fragility fractures, total lean mass, and ASM were associated with sarcopenia.

Conclusions: Higher prevalence of sarcopenia and sarcopenic obesity were found in female RA patients. Sarcopenia was found in younger female subjects with RA compared with healthy control subjects. Sarcopenia was associated with previous fragility fractures in female patients with RA.

Yerba mate (Ilex paraguariensis) is a xanthine-containing beverage, which is also rich in caffeine. Because caffeine has a negative impact on bone mineral density (BMD) mainly associated with low calcium (Ca) diets, there would be expected a negative effect of yerba mate on bone. In this study, Sprague-Dawley rats were used and randomly assigned into four groups (n = 6/group): Control + Ca 0.2 g %; Control + Ca 0.9 g %; Yerba + Ca 0.2 g %; Yerba + Ca 0.9 g %. At the end of the experiment, tibias and femurs were obtained for BMD, morphometric, histomorphometric, and biomechanical analyses. While there was no difference in bone parameters between rats with and without yerba mate consumption, a negative effect of low Ca diet was observed in BMD, morphometric, histomorphometric, and biomechanical results. Interaction between Ca content in the diet and yerba mate was only found in trabecular bone volume, which would indicate that the negative effect of low Ca intake on bone volume is reversed in part by yerba mate infusion. However, yerba mate was not able to reverse the negative effect of low Ca content on biomechanical properties and trabecular connectivity. In summary, at least in our study, yerba mate would not have a negative effect on bone and would be safe for the bone health of consumers.

Rheumatoid arthritis (RA) is a chronic systemic inflammatory autoimmune disease with high prevalence of osteoporosis. Previous evidence indicates an association between vitamin D deficiency and autoimmune diseases. The aim of this study was to evaluate serum 25 hydroxyvitamin D [25(OH)D] levels, bone mineral density (BMD) and disease activity in RA patients living in Argentina. We studied 34 RA women and 41 healthy women as a control group. RA patients had lower 25(OH)D levels (20.4 ± 0.9 ng/ml) than controls (26.3 ± 1.9 ng/ml; p < 0.05). No significant differences were found in lumbar spine BMD between premenopausal (preM) or postmenopausal (postM) patients, but femoral neck BMD was significantly lower in postM RA patients (T score -2.5 ± 0.4) than in postM control subjects (T score -0.9 ± 0.3, p = 0.014). Although no linear correlation between 25(OH)D levels and disease activity (DAS-28) was found, patients with moderate-high disease activity had lower 25(OH)D levels than those with low disease activity: DAS-28 >3.2: 19.5 ± 0.88 ng/ml; DAS-28 ≤3.2: 23.7 ± 2.8 ng/ml (p = 0.047). After 1 year of vitamin D treatment 25(OH)D levels were increased while DAS-28 were decreased (n = 25; p < 0.05). We conclude that patients with RA had lower 25(OH)D levels than the control group. Low levels of 25(OH)D were associated with moderate-high disease activity suggesting the importance of optimal 25(OH)D levels in RA patients. Femoral neck BMD was lower in postM RA patients. No differences in lumbar BMD were found between preM and postM RA patients, suggesting that bone mass evaluation in RA patients should include femoral neck BMD regardless of age.