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BACKGROUND AND AIMS: Correction of calcium and protein undernutrition using milk, yoghurt, and cheese in older adults in aged care homes is associated with reduced fractures and falls. However, these foods contain potentially atherogenic fats. We aimed to determine whether this intervention that increased dairy consumption to recommended levels adversely affects serum lipid profiles. METHOD AND RESULTS: This was a sub-group analysis of a 2-year cluster-randomised trial involving 60 aged care homes in Australia. Thirty intervention homes provided additional milk, yoghurt, and cheese on menus while 30 control homes continued with their usual menus. A sample of 159 intervention and 86 controls residents (69% female, median age 87.8 years) had dietary intakes recorded using plate waste analysis and fasting serum lipids measured at baseline and 12 months. Diagnosis of cardiovascular disease and use of relevant medications were determined from medical records. Outcome measures were serum total, HDL and LDL cholesterol and ApoA-1 & B. Intervention increased daily dairy servings from 1.9 ± 1.0 to 3.5 ± 1.4 (p < 0.001) while controls continued daily intakes of ≤2 servings daily (1.7 ± 1.0 to 2.0 ± 1.0 (p = 0.028). No group differences were observed for serum total cholesterol/high-density lipoprotein-C (TC/HDL-C) ratio, Apoprotein B/Apoprotein A-1 (ApoB/ApoA-1) ratio, low-density lipoprotein-C (LDL-C), non-HDL-C, or triglycerides (TGs) at 12 months. CONCLUSION: Among older adults in aged care homes, correcting insufficiency in intakes of calcium and protein using milk, yoghurt and cheese does not alter serum lipid levels, suggesting that this is a suitable intervention for reducing the risk of falls and fractures. CLINICAL TRIAL REGISTRY: Australian New Zealand Clinical Trials Registry (ACTRN12613000228785) 2012; https://www.anzctr.org.au.
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Low serum alkaline phosphatase (ALP) was found in 9% of patients attending an osteoporosis clinic, 0.6% of hospital patients, and 2/22 with an atypical femoral fracture. Hypophosphatasia was diagnosed in 3% of osteoporosis clinic patients with low ALP. Low ALP is a screening tool for hypophosphatasia, a condition potentially aggravated by antiresorptive therapy. INTRODUCTION: Hypophosphatasia (HPP) is an inherited disorder associated with impaired primary mineralisation of osteoid (osteomalacia). HPP may be misdiagnosed as osteoporosis, a reduction in the volume of normally mineralized bone. Both illnesses may result in fragility fractures, although stress and atypical fractures are more common in HPP. Antiresorptive therapy, first-line treatment for osteoporosis, is relatively contraindicated in HPP. Misdiagnosis and mistreatment can be avoided by recognising a low serum alkaline phosphatase (ALP). Our aim was to determine the prevalence of a low ALP (< 30 IU/L) in patients attending an osteoporosis clinic, in a hospital-wide setting, and in a group of patients with atypical femoral fractures (AFF). METHODS: This was a retrospective study of patients attending an osteoporosis clinic at a tertiary hospital during 8 years (2012-2020). Patients were categorised into those with a transiently low ALP, those with low ALP on ≥ 2 occasions but not the majority of measurements, and those with a persistently low ALP. ALP levels were also assessed in hospital-wide records and a group of patients with AFF. RESULTS: Of 1839 patients attending an osteoporosis clinic, 168 (9%) had ≥ 1 low ALP, 50 (2.7%) had low ALP for ≥ 2 months, and seven (0.4%) had persistently low ALP levels. HPP was diagnosed in five patients, four of whom had persistently low ALP levels. The prevalence of HPP was 0.3% in the osteoporosis clinic and 3% in patients with ≥ 1 low ALP. Low ALP occurred in 0.6% of all hospital patients and 2/22 with AFF. CONCLUSION: Persistently low ALP in osteoporosis clinic attendees is easy to identify and signals the possibility of hypophosphatasia, a condition that may be mistaken for osteoporosis and incorrectly treated with antiresorptive therapy.
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Fracturas Óseas , Hipofosfatasia , Osteoporosis , Humanos , Hipofosfatasia/complicaciones , Hipofosfatasia/diagnóstico , Hipofosfatasia/tratamiento farmacológico , Fosfatasa Alcalina , Estudios Retrospectivos , Fracturas Óseas/complicaciones , Osteoporosis/diagnóstico , Osteoporosis/tratamiento farmacológico , Osteoporosis/epidemiologíaRESUMEN
BACKGROUND: older adults in aged care account for 30% of the population burden of hip fractures. Nutritional interventions to correct under nutrition reduce these debilitating fractures, perhaps partly by reducing falls and slowing deterioration in bone morphology. OBJECTIVE: to determine whether a nutritional approach to fracture risk reduction in aged care homes is cost-effective. DESIGN: cost-effectiveness was estimated based on results from a prospective 2-year cluster-randomised controlled trial and secondary data. Intervention residents consumed a total of 3.5 daily servings of milk, yoghurt and/or cheese, resulting in 1,142 mg of calcium and 69 g of protein compared with the daily intakes of 700 mg of calcium and 58 g of protein consumed by the control group. SETTING: fifty-six aged care homes. PARTICIPANTS: residents for 27 intervention (n = 3,313) and 29 control (n = 3,911) homes. METHODS: ambulance, hospital, rehabilitation and residential care costs incurred by fracture were estimated. The incremental cost-effectiveness ratios per fracture averted within a 2-year time horizon were estimated from the Australian healthcare perspective applying a 5% discount rate on costs after the first year. RESULTS: intervention providing high-protein and high-calcium foods reduced fractures at a daily cost of AU$0.66 per resident. The base-case results showed that the intervention was cost-saving per fracture averted, with robust results in a variety of sensitivity and scenario analyses. Scaling the benefits of intervention equates to a saving of AU$66,780,000 annually in Australia and remained cost-saving up to a daily food expenditure of AU$1.07 per resident. CONCLUSIONS: averting hip and other non-vertebral fractures in aged care residents by restoring nutritional inadequacy of protein and calcium is cost-saving.
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Calcio , Fracturas de Cadera , Humanos , Anciano , Estudios Prospectivos , Australia , Fracturas de Cadera/prevención & control , AmbulanciasRESUMEN
Bone loss during advancing age is the net result of reduced modeling-based bone formation upon the outer (periosteal) envelope and unbalanced remodeling by basic multicellular units (BMUs) upon the three (intracortical, endocortical, and trabecular) components of the inner (endosteal) bone envelope. Each BMU deposits less bone than resorbed, reducing total bone volume and deteriorating the microstructure of the diminished residual bone volume.Antiresorptive agents like bisphosphonates reduce, but do not abolish, the rate of bone remodeling - fewer BMUs remodel, "turn over," the volume of bone. Residual unbalanced remodeling continues to slowly reduce total bone volume and deteriorate bone microstructure. By contrast, denosumab virtually abolishes remodeling so the decrease in bone volume and the deterioration in microstructure cease. The less remodeled matrix remains, leaving more time to complete the slow process of secondary mineralization which reduces the heterogeneity of matrix mineralization and allows it to become glycosylated, changes that may make the smaller and microstructurally deteriorated bone volume more brittle. Neither class of antiresorptive restores bone volume or its microstructure, despite increases in bone mineral density misleadingly suggesting otherwise. Nevertheless, these agents reduce vertebral and hip fractures by 50-60% but only reduce nonvertebral fractures by 20-30%.Restoring bone volume, microstructure, and material composition, "curing" bone fragility, may be partly achieved using anabolic therapy. Teriparatide, and probably abaloparatide, produce mainly remodeling-based bone formation by acting on BMUs existing in their resorption, reversal, or formation phase at the time of treatment and by promoting bone formation in newly initiated BMUs. Romosozumab produces modeling-based bone formation almost exclusively and decreases the surface extent of bone resorption. All three anabolic agents reduce vertebral fracture risk relative to untreated controls; parathyroid hormone 1-34 and romosozumab reduce vertebral fracture risk more greatly than risedronate or alendronate, respectively. Evidence for nonvertebral or hip fracture risk reduction relative to untreated or antiresorptive-treated controls is lacking or inconsistent. Only one study suggests sequential romosozumab followed by alendronate reduces vertebral, nonvertebral, and hip fracture risk compared to continuous alendronate alone. Whether combined antiresorptive and anabolic therapy result in superior fracture risk reduction than monotherapy is untested.
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Conservadores de la Densidad Ósea , Osteoporosis , Densidad Ósea/fisiología , Remodelación Ósea/fisiología , Huesos , HumanosRESUMEN
PURPOSE OF REVIEW: Bone densitometry provides a two-dimensional projected areal apparent bone mineral density that fails to capture the heterogeneity of bone's material composition and macro-, micro-, and nano-structures critical to its material and structural strength. Assessment of the structural basis of bone fragility has focused largely on trabecular bone based on the common occurrence of fragility fractures at sites with substantial amounts of trabecular bone. This review focuses on the contribution of cortical bone to bone fragility throughout life. RECENT FINDINGS: Accurately differentiating cortical and trabecular bone loss has important implications in quantifying bone fragility as these compartments have differing effects on bone strength. Recent advances in imaging methodology have improved distinction of these two compartments by (i) recognition of a cortico-trabecular transitional zone and (ii) quantifying bone microstructure in a region of interest that is a percentage of bone length rather than a fixed point. Additionally, non-invasive three-dimensional imaging methods allow more accurate quantification of changes in the cortical, trabecular, and cortico-trabecular compartments during growth, aging, disease, and treatment. Over 75% of the skeleton is assembled as cortical bone. Of all fragility fractures, ~ 80% are appendicular and involve regions rich in cortical bone and ~ 70% of all age-related appendicular bone loss is cortical and is mainly due to unbalanced intracortical remodeling which increases cortical porosity. The failure to achieve the optimal peak bone microstructure during growth due to disease and the deterioration in cortical and trabecular bone produced by bone loss compromise bone strength. The loss of strength produced by microstructural deterioration is disproportionate to the bone loss producing this deterioration. The reason for this is that the loss of strength increases as a 7th power function of the rise in cortical porosity and a 3rd power function of the fall in trabecular density (Schaffler and Burr in J Biomech. 21(1):13-6, 1988), hence the need to quantify bone microstructure.
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Envejecimiento , Desarrollo Óseo , Hueso Esponjoso/diagnóstico por imagen , Hueso Cortical/diagnóstico por imagen , Osteoporosis/diagnóstico por imagen , Fracturas Osteoporóticas/fisiopatología , Densidad Ósea , Remodelación Ósea , Huesos/diagnóstico por imagen , Huesos/fisiopatología , Huesos/ultraestructura , Hueso Esponjoso/fisiopatología , Hueso Esponjoso/ultraestructura , Hueso Cortical/fisiopatología , Hueso Cortical/ultraestructura , Humanos , Imagenología Tridimensional , Osteoporosis/fisiopatología , PorosidadRESUMEN
Malnutrition in institutionalised elderly increases morbidity and care costs. Meat and dairy foods are high-quality protein sources so adequate intakes may reduce malnutrition risk. We aimed to determine whether inadequate intakes of meat and dairy foods contribute to malnutrition in institutionalised elderly. This cross-sectional study involved 215 elderly residents (70·2 % females, mean age 85·8 years) from twenty-one aged-care facilities in Melbourne, Australia. Dietary intake was assessed using observed plate waste. Food groups and serving sizes were based on the Australian Guide to Healthy Eating. Nutrient content was analysed using a computerised nutrient analysis software (Xyris). Malnutrition risk was assessed using the Mini Nutrition Assessment (MNA) tool; a score between 24 and 30 indicates normal nutritional status. Data were analysed using robust regression. Mean MNA score was 21·6 (sd 2·7). In total, 68 % of residents were malnourished or at risk of malnutrition (MNA score≤23·5). Protein intake was 87 (sd 28) % of the Australian recommended dietary intake (RDI). Consumption averaged 1 serving each of dairy foods and meat daily. Number of dairy and meat servings related to proportion of protein RDI (both P24 points). Provision of meat and dairy foods did not meet recommended levels. On the basis of current dietary intakes in aged-care residents, increasing consumption of dairy foods to the recommended four servings daily ensures protein adequacy and may reduce malnutrition risk in institutionalised elderly, and so reduce risk of comorbidities and costs associated with malnutrition.
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Productos Lácteos , Suplementos Dietéticos , Desnutrición/prevención & control , Anciano de 80 o más Años , Femenino , Servicios de Alimentación , Hogares para Ancianos , Humanos , Masculino , Necesidades Nutricionales , Estado NutricionalRESUMEN
BACKGROUND: Disability, mortality and healthcare burden from fractures in older people is a growing problem worldwide. Observational studies suggest that aspirin may reduce fracture risk. While these studies provide room for optimism, randomised controlled trials are needed. This paper describes the rationale and design of the ASPirin in Reducing Events in the Elderly (ASPREE)-Fracture substudy, which aims to determine whether daily low-dose aspirin decreases fracture risk in healthy older people. METHODS: ASPREE is a double-blind, randomised, placebo-controlled primary prevention trial designed to assess whether daily active treatment using low-dose aspirin extends the duration of disability-free and dementia-free life in 19â 000 healthy older people recruited from Australian and US community settings. This substudy extends the ASPREE trial data collection to determine the effect of daily low-dose aspirin on fracture and fall-related hospital presentation risk in the 16â 500 ASPREE participants aged ≥70â years recruited in Australia. The intervention is a once daily dose of enteric-coated aspirin (100â mg) versus a matching placebo, randomised on a 1:1 basis. The primary outcome for this substudy is the occurrence of any fracture-vertebral, hip and non-vert-non-hip-occurring post randomisation. Fall-related hospital presentations are a secondary outcome. DISCUSSION: This substudy will determine whether a widely available, simple and inexpensive health intervention-aspirin-reduces the risk of fractures in older Australians. If it is demonstrated to safely reduce the risk of fractures and serious falls, it is possible that aspirin might provide a means of fracture prevention. TRIAL REGISTRATION NUMBER: The protocol for this substudy is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12615000347561).
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Accidentes por Caídas/estadística & datos numéricos , Aspirina/administración & dosificación , Aspirina/farmacología , Inhibidores de la Ciclooxigenasa/administración & dosificación , Inhibidores de la Ciclooxigenasa/farmacología , Fracturas Óseas/prevención & control , Prevención Primaria , Actividades Cotidianas , Anciano , Australia/epidemiología , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Estudios Observacionales como Asunto , Prevención Primaria/métodos , Autocuidado , Estados Unidos/epidemiologíaRESUMEN
PURPOSE OF REVIEW: Trabecular bone loss and vertebral fractures are historical hallmarks of osteoporosis. During the past 70 years, this view has dominated research aiming to understand the structural basis of bone fragility. We suggest this notion needs to be revised to recognize and include the role of cortical bone deterioration as an important determinant of bone strength throughout life. RECENT FINDINGS: About 80% of the fragility fractures involve the appendicular skeleton, at regions comprising large amounts of cortical bone. Up to 70% of the age-related bone loss at these locations is the result of intracortical remodeling that cavitates cortical bone producing porosity. It is now possible to accurately quantify cortical porosity in vivo and use this information to understand the pathogenesis of bone fragility throughout life, assist in identifying patients at risk for fracture, and use this as a potential marker to monitor the effects of treatment on bone structure and strength. SUMMARY: Cortical bone has an important role in determining bone strength. The loss of strength is the result of intracortical and endocortical remodeling imbalance that produces cortical porosity and thinning. Studies are needed to determine whether porosity is an independent predictor of fracture risk and whether a reduction in porosity serves as a surrogate of antifracture efficacy.
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Densidad Ósea/fisiología , Remodelación Ósea/fisiología , Fracturas Osteoporóticas/fisiopatología , Humanos , Osteoporosis/fisiopatología , PorosidadRESUMEN
Three-dimensional (3D) characterization of cortical porosity, most of which is under 100 µm in diameter, is usually confined to measurements made in 3-4 mm diameter cylinders of bone. We used micro-computed tomography (micro-CT) scanning of entire transaxial cross sections of human proximal femoral shafts (30-35 mm diameter) to quantify regional variation in porosity within the same scan. Complete, up to 10-mm-thick, transaxial slices of femoral upper shafts from 8 female cadavers were studied (n = 3 aged 29-37 years, n = 5 aged 72-90 years). Scanning was performed using high-resolution micro-CT (8.65 µm/voxel). Micro-CT volumes (10 × 10 × 5 mm) were selected via software in the anterior, medial and lateral regions. Images were segmented with voids appearing as 3D-interconnected canals. The percent void-to-tissue volume (Vo.V/TV) and the corresponding void surface area/TV were 86-309% higher in older than younger subjects in anterior (p = 0.034), medial (p = 0.077), and lateral aspects (p = 0.034). Although not significant, void separation was reciprocally lower by 19-39%, and void diameter was 65% larger in older than younger subjects; void number tended to be 24-25% higher medially and laterally but not anteriorly. For all specimens combined, medially there was higher Vo.V/TV and void surface area/TV than anteriorly (+48%, p = 0.018; +33%, p = 0.018) and laterally (+56%, p = 0.062; +36%, p = 0.043). There is regional heterogeneity in the 3D microarchitecture of the intracortical canals of the femoral shaft. The higher void volume in advanced age appears to be due to larger, rather than more, pores. However, creation of new canals from existing canals may contribute, depending on the location. High-resolution micro-computed tomography scanning of entire bone segments enables quantification of the 3D microanatomy of the intracortical void network at multiple locations.
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Fémur/diagnóstico por imagen , Osteoporosis/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Cadáver , Femenino , Humanos , Imagenología Tridimensional/métodos , Porosidad , Microtomografía por Rayos XRESUMEN
CONTEXT: Menopause is associated with changes in musculoskeletal, body composition, and metabolic parameters that may be amplified in premenopausal women receiving estradiol suppression for breast cancer. Denosumab offsets deleterious skeletal effects of estradiol suppression and has been reported to have effects on body composition and metabolic parameters in pre-clinical and observational studies, though evidence from double-blind randomized controlled trials is limited. OBJECTIVE: To assess the effect of denosumab on body composition and metabolic parameters. METHODS: In a pre-specified secondary analysis of a 12-month randomized, double-blind, placebo-controlled trial, 68 premenopausal women with breast cancer initiating ovarian function suppression and aromatase inhibition were randomized to denosumab 60-mg or placebo administered at baseline and 6 months. Outcome measures were total and regional fat and lean mass (DXA), body mass index (BMI), waist and hip circumference, fasting glucose, HOMA-IR, and lipid profile. Using a mixed model, between-group mean adjusted differences, MAD, [95% confidence interval], over time are reported. RESULTS: Over 12 months, relative to placebo, android and gynoid fat mass decreased in the denosumab group (-266â g [95%CI -453 to -79], P = 0.02, and -452â g [95%CI -783 to -122], P = 0.03, respectively). Total fat mass and waist circumference were lower in the denosumab group but not significantly so (-1792g [95% CI -3346 to -240], P = 0.08 and (- 3.77â cm [95% CI -6.76 to -0.79], P = 0.06, respectively). No significant treatment effects were detected in lean mass, BMI, hip circumference, fasting glucose, HOMA-IR, or lipid profile. CONCLUSIONS: In premenopausal women receiving estradiol suppression, denosumab decreases some measures of fat mass with no detectable effects on other measures of body composition or metabolic parameters.
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PURPOSE: Suppression of ovarian function and aromatase inhibition (AI) increases disease-free survival in premenopausal women with estrogen receptor (ER)-positive early-stage breast cancer but accelerates bone loss. We therefore hypothesized that suppressing bone remodeling using denosumab (DMAB) would prevent bone loss in these women. METHODS: In a 12-month double-blind randomized trial, 68 women with ER-positive early-stage breast cancer commencing ovarian function suppression and AI were randomly assigned to 60 mg DMAB (n = 34) or placebo (PBO; n = 34) once every 6 months (at 0 and 6 months). Volumetric bone mineral density (BMD), microarchitecture, and estimated bone strength of the distal tibia and distal radius were measured using high-resolution peripheral quantitative computed tomography, and spine and hip BMD were measured using dual-energy X-ray absorptiometry at 0, 6, and 12 months. The primary end point and treatment effect was the mean adjusted between group difference (MAD; [95% CI]) in distal tibial total volumetric BMD over 12 months, with a single P value tested over all time points. The study is registered with the Australian New Zealand Clinical Trials Registry (anzctr.org.au; identifier: ACTRN12616001051437). RESULTS: Intention-to-treat analysis included all 68 randomly assigned women. Over 12 months, compared with PBO, DMAB prevented the decrease in distal tibial total BMD (MAD, 20.8 mg HA/cm3 [95% CI, 17.3 to 24.2]), cortical BMD (42.9 mg HA/cm3 [95% CI, 32.1 to 53.9]), trabecular BMD (3.32 mg HA/cm3 [95% CI, 1.45 to 5.20], P = .004), estimated stiffness (11.6 kN/m [95% CI, 7.6 to 15.6]), and failure load (563 N [95% CI, 388 to 736]). Findings were similar at the distal radius. Decreases in BMD at the lumbar spine (MAD, 0.13 g/cm2 [95% CI, 0.11 to 0.15]), total hip (0.08 g/cm2 [95% CI, 0.07 to 0.09], and femoral neck (0.06 g/cm2 [95% CI, 0.05 to 0.07]) were also prevented. All P < .001 unless otherwise noted. CONCLUSION: Treatment with DMAB at commencement of estradiol suppression therapy preserves BMD, bone microarchitecture, and estimated strength, and is likely to increase fracture-free survival.
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BACKGROUND: Aging increases fracture risk through bone loss and microarchitecture deterioration due to an age-related imbalance in bone resorption and formation during bone remodelling. We examined the associations between levels of phosphate, calcium, and alkaline phosphatase, and fracture risk in initially-healthy older individuals. METHODS: A post-hoc analysis of the Aspirin in Reducing Events in the Elderly (ASPREE) trial recruited 16,703 Australian participants aged ≥70 years and 2,411 US participants aged ≥65 years. Analyses were conducted on ASPREE-Fracture substudy participants from Australia with serum calcium, phosphate, and alkaline phosphatase measurement. Fracture data were collected post-randomization. Cox regression was used to calculate hazard ratios (HR) and 95% confidence intervals (CIs). Phosphate, calcium, and alkaline phosphatase were analysed in deciles (D1-D10), with deciles 4-7 (31-70%) as the reference category. Restricted cubic spline curves were used to identify nonlinear associations. RESULTS: Of the 9915 participants, 907 (9·2%) persons had incident fractures recorded over 3·9 (SD 1·4) years. In the fully adjusted model, males in the top decile (D10) of phosphate had 78% higher risk of incident fracture (HR 1·78, 95% CI 1·25-2·54). No such association was observed for females (HR 1·09, 95% CI 0·83-1·44). The population attributable fraction in men within the D10 phosphate category is 6·9%. CONCLUSION: This result confirms that, high-normal serum phosphate levels are associated with increased fracture risk in older men.
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Bone is continuously in a state of building and renewal, though the process of remodeling that takes place at many sites asynchronously throughout the skeleton, with bone formation and resorption equal at these sites (bone multicellular units). Remodeling takes place on bone surfaces, both on trabeculae and in the cortex, and serves the purposes of replacing old bone or that damaged by microfractures throughout the skeleton. The bone loss and consequent osteoporotic fractures that result from excess resorption over formation have mainly been prevented or treated by antiresorptive drugs that inhibit osteoclast formation and/or activity. Virtually all of the evidence leading to acceptance of antiresorptive drugs as treatment has depended upon their prevention of vertebral fractures. In recent decades, new prospects came of anabolic treatments that partly restore bone volume and microstructure restore bone that has been lost. The first of these was parathyroid hormone (PTH), shown by daily injection to increase markers of bone formation and prevent fractures. This field of interest enlarged with the discovery of PTH-related protein (PTHrP), so closely related in structure and action to PTH. The structural relationship between PTH and PTHrP is important in assessing their physiological and pharmacological roles, with the N-terminal domains of the 2 having virtually equal actions on target cells. Abaloparatide, a peptide analogue based on the structures of PTHrP and PTH, has been approved in some countries as a therapy for osteoporosis. Treatment through the PTH receptor activation pathway, and probably with any anabolic therapy, needs to be followed by antiresorptive treatment in order to maintain bone that has been restored. No matter how effective anabolic therapies for the skeleton become, it seems highly likely that there will be a continuing need for antiresorptive drugs.
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Densidad Ósea , Huesos , Adolescente , Adulto , Estudios Transversales , Humanos , Masculino , Fenotipo , Adulto JovenAsunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Densidad Ósea/efectos de los fármacos , Remodelación Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/tratamiento farmacológico , Fracturas Óseas/prevención & control , Insuficiencia Renal Crónica/terapia , Conservadores de la Densidad Ósea/efectos adversos , Huesos/diagnóstico por imagen , Huesos/fisiopatología , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/diagnóstico , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/etiología , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/fisiopatología , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/etiología , Fracturas Óseas/fisiopatología , Humanos , Valor Predictivo de las Pruebas , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/fisiopatología , Factores de RiesgoRESUMEN
BACKGROUND: Age-related trabecular microstructural deterioration and conversion from plate-like trabeculae to rod-like trabeculae occur because of unbalanced rapid remodeling. As denosumab achieves greater remodeling suppression and lower cortical porosity than alendronate, we hypothesized that denosumab might also preserve trabecular plate microstructure, bone stiffness and strength more effectively than alendronate. METHODS: In this post hoc analysis of a phase 2 study, postmenopausal women randomized to placebo (P, n = 74), denosumab (D, n = 72), or alendronate (A, n = 68). HR-pQCT scans of the distal radius and tibia were performed at baseline and Month-12 (M12). Trabecular compartment was subjected to Individual Trabecula Segmentation while finite element analysis was performed to estimate stiffness and strength. Percent change from baseline at M12 of each parameter was compared between patient groups. RESULTS: At the distal tibia, in the placebo group, plate surface area (pTb.S, -1.3%) decreased while rod bone volume fraction (rBV/TV, +4.5%) and number (rTb.N, +2.1%) increased. These changes were prevented by denosumab but persisted despite alendronate therapy (pTb.S: -1.7%; rBV/TV: +6.9%; rTb.N: +3.0%). Both treatments improved whole bone stiffness (D: +3.1%; A: +1.8%) and failure load (D: +3.0%; A: +2.2%); improvements using denosumab was significant compared to placebo (stiffness: p = 0.004; failure load: p = 0.003). At the distal radius, denosumab increased total trabecular bone volume fraction (BV/TV, +3.4%) and whole bone failure load (+4.0%), significantly different from placebo (BV/TV: p = 0.044; failure load: p = 0.046). Significantly different effects of either drug on plate and rod microstructure were not detected. CONCLUSIONS: Denosumab preserved trabecular plate microstructure. Alendronate did not. However, estimated strength did not differ between denosumab and alendronate treated groups.
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Alendronato , Denosumab , Alendronato/farmacología , Alendronato/uso terapéutico , Densidad Ósea , Denosumab/farmacología , Denosumab/uso terapéutico , Femenino , Humanos , Radio (Anatomía)/diagnóstico por imagen , Tibia/diagnóstico por imagenRESUMEN
INTRODUCTION: Measurement of bone mineral density (BMD) is recommended in patients with chronic kidney disease (CKD). However, most persons in the community and most patients with CKD have osteopenia, suggesting fracture risk is low. Bone loss compromises bone microarchitecture which increases fragility disproportionate to modest deficits in BMD. We therefore hypothesized that patients with CKD have reduced estimated failure load due to deterioration in microarchitecture irrespective of whether they have normal femoral neck (FN) BMD, osteopenia or osteoporosis. METHODS: We measured distal tibial and distal radial microarchitecture in 128 patients with CKD and 275 age- and sex-matched controls using high resolution peripheral quantitative computed tomography, FN-BMD using bone densitometry and estimated failure load at the distal appendicular sites using finite element analysis. RESULTS: Patients versus controls respectively had: lower tibial cortical area 219 (40.7) vs. 237 (35.3) mm2, p = 0.002, lower cortical volumetric BMD 543 (80.7) vs. 642 (81.7) mgHA/cm3 due to higher porosity 69.6 (6.19) vs. 61.9 (6.48)% and lower matrix mineral density 64.2 (0.62) vs. 65.1 (1.28)%, lower trabecular vBMD 92.2 (41.1) vs. 149 (43.0) mgHA/cm3 due to fewer and spatially disrupted trabeculae, lower FN-BMD 0.78 (0.12) vs. 0.94 (0.14) g/cm2 and reduced estimated failure load 3825 (1152) vs. 5778 (1467) N, all p < 0.001. Deterioration in microarchitecture and estimated failure load was most severe in patients and controls with osteoporosis. Patients with CKD with osteopenia and normal FN-BMD had more deteriorated tibial microarchitecture and estimated failure load than controls with BMD in the same category. In univariate analyses, microarchitecture and FN-BMD were both associated with estimated failure load. In multivariable analyses, only microarchitecture was independently associated with estimated failure load and accounted for 87% of the variance. CONCLUSIONS: Bone fragility is likely to be present in patients with CKD despite them having osteopenia or normal BMD. Measuring microarchitecture may assist in targeting therapy to those at risk of fracture.
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Enfermedades Óseas Metabólicas , Huesos , Osteoporosis , Insuficiencia Renal Crónica , Absorciometría de Fotón , Densidad Ósea , Enfermedades Óseas Metabólicas/complicaciones , Huesos/anatomía & histología , Humanos , Radio (Anatomía) , Insuficiencia Renal Crónica/complicacionesRESUMEN
Gender-affirming hormone therapy aligns physical characteristics with an individual's gender identity, but sex hormones regulate bone remodeling and influence bone morphology. We hypothesized that trans men receiving testosterone have compromised bone morphology because of suppression of ovarian estradiol production, whereas trans women receiving estradiol, with or without anti-androgen therapy, have preserved bone microarchitecture. We compared distal radial and tibial microarchitecture using high-resolution peripheral quantitative computed tomography images in a cross-sectional study of 41 trans men with 71 cis female controls, and 40 trans women with 51 cis male controls. Between-group differences were expressed as standardized deviations (SD) from the mean in age-matched cisgender controls with 98% confidence intervals adjusted for cross-sectional area (CSA) and multiple comparisons. Relative to cis women, trans men had 0.63 SD higher total volumetric bone mineral density (vBMD; both p = 0.01). Cortical vBMD and cortical porosity did not differ, but cortices were 1.11 SD thicker (p < 0.01). Trabeculae were 0.38 SD thicker (p = 0.05) but otherwise no different. Compared with cis men, trans women had 0.68 SD lower total vBMD (p = 0.01). Cortical vBMD was 0.70 SD lower (p < 0.01), cortical thickness was 0.51 SD lower (p = 0.04), and cortical porosity was 0.70 SD higher (p < 0.01). Trabecular bone volume (BV/TV) was 0.77 SD lower (p < 0.01), with 0.57 SD fewer (p < 0.01) and 0.30 SD thicker trabeculae (p = 0.02). There was 0.56 SD greater trabecular separation (p = 0.01). Findings at the distal radius were similar. Contrary to each hypothesis, bone microarchitecture was not compromised in trans men, perhaps because aromatization of administered testosterone prevented bone loss. Trans women had deteriorated bone microarchitecture either because of deficits in microstructure before treatment or because the estradiol dosage was insufficient to offset reduced aromatizable testosterone. Prospective studies are needed to confirm these findings. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
Asunto(s)
Personas Transgénero , Absorciometría de Fotón , Adulto , Densidad Ósea/fisiología , Estudios Transversales , Estradiol , Femenino , Identidad de Género , Humanos , Masculino , Minerales , Radio (Anatomía)/anatomía & histología , Testosterona , Tibia/fisiologíaRESUMEN
Importance: Falls and fractures are frequent and deleterious to the health of older people. Aspirin has been reported to reduce bone fragility and slow bone loss. Objective: To determine if daily low-dose aspirin (100 mg) reduces the risk of fractures or serious falls (fall-related hospital presentations) in healthy older men and women. Design, Setting, and Participants: This substudy of a double-blind, randomized, placebo-controlled trial studied older adult men and women in 16 major sites across southeastern Australia. The ASPREE-FRACTURE substudy was conducted as part of the Australian component of the ASPREE trial. Between 2010 and 2014 healthy (free of cardiovascular disease, dementia or physical disability), community-dwelling volunteers aged 70 years or older were recruited to participate in the ASPREE trial. Potentially eligible participants were identified by medical practitioners and trial personnel and were then sent a letter of invitation to participate. Interested participants were screened for suitability. Eligible participants with medical practitioner authorization and adherent to a 4-week run-in medication trial were randomized. Data were analyzed from October 17, 2019, to August 31, 2022. Interventions: Participants in the intervention group received a daily dose of oral 100 mg enteric-coated (low-dose) aspirin. The control group received a daily identical enteric-coated placebo tablet. Main Outcomes and Measures: The primary outcome of ASPREE-FRACTURE was the occurrence of any fracture. The secondary outcome was serious fall resulting in hospital presentation. Results: In total, 16â¯703 people with a median (IQR) age of 74 (72-78) years were recruited, and 9179 (55.0%) were women. There were 8322 intervention participants and 8381 control participants included in the primary and secondary outcome analysis of 2865 fractures and 1688 serious falls over the median follow-up of 4.6 years. While there was no difference in the risk of first fracture between the intervention and control participants (hazard ratio, 0.97; 95% CI, 0.87-1.06; P = .50), aspirin was associated with a higher risk of serious falls (total falls 884 vs 804; incidence rate ratio, 1.17; 95% CI, 1.03-1.33; P = .01). Results remained unchanged in analyses that adjusted for covariates known to influence fracture and fall risk. Conclusions and Relevance: In this substudy of a randomized clinical trial, the failure of low-dose aspirin to reduce the risk of fractures while increasing the risk of serious falls adds to evidence that this agent provides little favorable benefit in a healthy, White older adult population. Trial Registration: This substudy is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12615000347561).
Asunto(s)
Aspirina , Fracturas Óseas , Masculino , Humanos , Femenino , Anciano , Australia/epidemiología , Aspirina/uso terapéutico , Fracturas Óseas/epidemiología , Fracturas Óseas/prevención & control , Vida IndependienteRESUMEN
Peak bone mass achieved in adolescence is a determinant of bone mass in later life. In order to identify genetic variants affecting bone mineral density (BMD), we performed a genome-wide association study of BMD and related traits in 1518 children from the Avon Longitudinal Study of Parents and Children (ALSPAC). We compared results with a scan of 134 adults with high or low hip BMD. We identified associations with BMD in an area of chromosome 12 containing the Osterix (SP7) locus, a transcription factor responsible for regulating osteoblast differentiation (ALSPAC: P = 5.8 x 10(-4); Australia: P = 3.7 x 10(-4)). This region has previously shown evidence of association with adult hip and lumbar spine BMD in an Icelandic population, as well as nominal association in a UK population. A meta-analysis of these existing studies revealed strong association between SNPs in the Osterix region and adult lumbar spine BMD (P = 9.9 x 10(-11)). In light of these findings, we genotyped a further 3692 individuals from ALSPAC who had whole body BMD and confirmed the association in children as well (P = 5.4 x 10(-5)). Moreover, all SNPs were related to height in ALSPAC children, but not weight or body mass index, and when height was included as a covariate in the regression equation, the association with total body BMD was attenuated. We conclude that genetic variants in the region of Osterix are associated with BMD in children and adults probably through primary effects on growth.