ABSTRACT
ABSTRACT Objective: To evaluate changes in bone density and architecture in postmenopausal women with breast cancer (BC) and use of aromatase inhibitor (AI). Subjects and methods: Thirty-four postmenopausal women with BC, without bone metastasis, renal function impairment and who were not receiving bone-active drugs were selected from a population of 523 outpatients treated for BC. According to the presence of hormonal receptors, HER2 and Ki67, seventeen had positive hormonal receptors and received anastrozole (AI group), and seventeen were triple-negative receptors (non-AI group), previously treated with chemotherapy. Areal bone mineral density (aBMD) and vertebral fracture assessment (VFA) analyses were performed by DXA; vBMD and bone microarchitecture were evaluated by HR-pQCT. Fracture risk was estimated using the FRAX tool. Results: No patient referred previous low-impact fracture, and VFA detected one moderate vertebral fracture in a non-AI patient. AI patients showed lower aBMD and BMD T-scores at the hip and 33% radius and a higher proportion of osteoporosis diagnosis on DXA (47%) vs non-AI (17.6%). AI group had significantly lower values for vBMD at the entire, cortical and trabecular bone compartments, cortical and trabecular thickness and BV/TV. They also had a higher risk for major fractures and for hip fractures estimated by FRAX. Several HR-pQCT parameters evaluated at distal radius and distal tibia were significantly associated with fracture risk. Conclusion: AI is associated with alterations in bone density and microarchitecture of both the cortical and trabecular compartments. These findings explain the overall increase in fracture risk in this specific population.
Subject(s)
Humans , Female , Osteoporosis , Breast Neoplasms/drug therapy , Radius , Tibia , Absorptiometry, Photon , Bone Density , Aromatase Inhibitors/adverse effectsABSTRACT
To evaluate the bone strength and structure of patients with obstructive sleep apnea(OSA)by the high-resolution peripheral quantitative computed tomography(HR-pQCT)and to explore the relationship between OSA and osteoporosis. Male patients who visited the Sleep Respiratory Center of our hospital from August 2017 to January 2019 were consecutively recruited.Clinical data including the results of Epworth sleep scale(ESS)scoring and overnight polysomnography were collected.HR-pQCT was used to compare the differences in bone geometry,density,and microstructure between OSA patients and non-OSA people;also,the radius and tibia on the non-dominant side were measured to explore the relationship between OSA and osteoporosis. A total of 83 subjects were enrolled in the study.The number of patients in the mild,moderate,and severe OSA groups and non-OSA group were 21,18,34,and 10,respectively.There was no significant difference in age,blood pressure,ESS score,sleep stage,and sleep efficiency among these four groups(>0.05).Body mass index(BMI)and neck circumference were significantly different among these groups(=4.234,=0.008;=3.100,=0.031).There was no significant difference in the radius indicators(>0.05).For tibia,there were significant differences among the four groups in the cortical area(Ct.Ar)(=3.937,=0.011).There were also significant differences in the bone microstructural indicators including trabecular thickness(Tb.Th)and cortical thickness(Ct.Th)(=6.247,=0.001;=3.746,=0.014),which were significantly lower in the three OSA groups than in the control group.Pairwise comparisons showed that the Ct.Ar in the severe OSA group was significantly higher than that in the mild OSA group(=0.019)and Tb.Th in the control group was significantly higher than those in the mild and moderate OSA groups(=0.006,=0.001).Correlation analysis showed that,within a certain range,total volumetric bone mineral density(Tt.vBMD)and Tb.Th of radius and tibia were negatively correlated with age(=-0.312,=0.004;=-0.328,=0.002;=-0.265,=0.015;=-0.280,=0.010)and positively correlated with BMI(=0.240,=0.029;=0.369,=0.004;=0.299,=0.006;=0.416,=0.010).Stepwise multiple regression analysis showed that Tb.Th of radius and tibia were mostly correlated with BMI(=0.262,=0.008,=0.243,=6.270,=0.000;=0.494,=0.000,=0.186,=7.243,=0.000)and age(=-0.216,=0.030,=0.243,=6.270,=0.000;=-0.306,=0.003,=0.186,=7.243,=0.000).Tt.vBMD of radius had a certain correlation with sleep efficiency and with the decreasing nocturnal mean oxygen saturation caused by OSA(=0.312,=0.002, =-0.249,=0.012,=0.327,=7.482,=0.000). In non-elderly male populations,OSA mainly causes a decrease in Tb.Th and Ct.Th of the tibia.The changes in bone strength and structure are mainly related with age and body size and also have certain correlations with sleep efficiency and with the decreasing nocturnal mean oxygen saturation caused by OSA.
Subject(s)
Humans , Male , Bone Density , Bone and Bones , Polysomnography , Sleep Apnea, Obstructive , Tomography, X-Ray ComputedABSTRACT
Trabecular microstructure is an important factor in determining bone strength and physiological function. Normal X-ray and computed tomography (CT) cannot accurately reflect the microstructure of trabecular bone. High-resolution peripheral quantitative computed tomography (HR-pQCT) is a new imaging technique in recent years. It can qualitatively and quantitatively measure the three-dimensional microstructure and volume bone mineral density of trabecular bone . It has high precision and relative low dose of radiation. This new imaging tool is helpful for us to understand the trabecular microstructure more deeply. The finite element analysis of HR-pQCT data can be used to predict the bone strength accurately. We can assess the risk of osteoporosis and fracture with three-dimensional reconstructed images and trabecular microstructure parameters. In this review, we summarize the technical flow, data parameters and clinical application of HR-pQCT in order to provide some reference for the popularization and extensive application of HR-pQCT.
ABSTRACT
RESUMOA tomografia computadorizada quantitativa periférica de alta resolução (HR-pQCT) é uma nova tecnologia disponível comercialmente há menos de 10 anos que permite a feitura de exames in vivo para a avaliação de parâmetros ósseos. A HR-pQCT avalia a forma, o número, o volume, a densidade, a conectividade e a separação das trabéculas; a densidade e a espessura do osso cortical e o volume e a densidade total, em alta definição, o que permite a construção digital da microarquitetura óssea adicionalmente. A aplicação de cálculos matemáticos aos dados capturados, método denominado elemento finito (FE), permite a estimativa das propriedades físicas do tecido e simula cargas suportadas de forma não invasiva. Desse modo, a HR-pQCT adquire simultaneamente dados antes fornecidos separadamente pela densitometria óssea, pela ressonância magnética e pela histomorfometria e agrega estimativas biomecânicas antes só possíveis em tecidos extraídos. A reprodutibilidade do método é satisfatória, com coeficientes de variação que raramente ultrapassam os 3%. Quanto à acurácia, os parâmetros apresentam de regular a boa concordância (r2= 0,37-0,97).A principal aplicação clínica é na quantificação e no monitoramento das doenças osteometabólicas, porque avalia de modo mais completo a resistência óssea e o risco de fratura. Na artrite reumatoide permite-se a aferição do número e do tamanho das erosões e dos cistos, além do espaço articular. Na osteoartrite é possível caracterizar as áreas edema-símile que guardam correlação com a degradação da cartilagem.Restritas ainda a um instrumento de pesquisa, dado o seu elevado custo, a alta resolução e a eficiência mostram-se como vantagens em relação aos métodos atualmente usados para a avaliação óssea, com um potencial para tornar-se uma importante ferramenta na prática clínica.
ABSTRACTHigh resolution peripheral quantitative computed tomography (HR-pQCT) is a new technology commercially available for less than 10 years that allows performing in vivo assessment of bone parameters. HR-pQCT assesses the trabecular thickness, trabecular separation, trabecular number and connectivity density and, in addition, cortical bone density and thickness and total bone volume and density in high-definition mode, which additionally allows obtaining digital constructs of bone microarchitecture. The application of mathematics to captured data, a method called finite element analysis (FEA), allows the estimation of the physical properties of the tissue, simulating supported loads in a non-invasive way. Thus, HR-pQCT simultaneously acquires data previously provided separately by dual energy x-ray absorptiometry (DXA), magnetic resonance imaging and histomorphometry, aggregating biomechanical estimates previously only possible in extracted tissues. This method has a satisfactory reproducibility, with coefficients of variation rarely exceeding 3%. Regarding accuracy, the method shows a fair to good agreement (r2 = 0.37-0.97).The main clinical application of this method is in the quantification and monitoring of metabolic bone disorders, more fully evaluating bone strength and fracture risk. In rheumatoid arthritis patients, this allows gauging the number and size of erosions and cysts, in addition to joint space. In osteoarthritis, it is possible to characterize the bone marrow edema-like areas that show a correlation with cartilage breakdown.Given its high cost, HR-pQCT is still a research tool, but the high resolution and efficiency of this method reveal advantages over the methods currently used for bone assessment, with a potential to become an important tool in clinical practice.