RESUMEN
More than 70% of women sustaining fractures have osteopenia or "normal" bone mineral density (BMD). These women remain undetected using the BMD threshold of -2.5 SD for osteoporosis. As microstructural deterioration increases bone fragility disproportionate to the bone loss producing osteopenia/normal BMD, we hypothesized that the structural fragility score (SFS) of ≥70 units, a measure capturing severe cortical and trabecular deterioration, will identify these women. Distal radial images were acquired using high-resolution peripheral quantitative tomography in postmenopausal French women, mean age 67 years (range 42-96 years); 1539 women were followed for 4 years (QUALYOR) and 561 women followed for 8 years (OFELY). Women with osteopenia or normal BMD accounted for ~80% of fractures. Women ≥70 years, 29.2% of the cohort, accounted for 39.2% to 61.5% of fractures depending on follow-up duration. Women having fractures had a higher SFS, lower BMD, and a higher fracture risk assessment score (FRAX) than women remaining fracture-free. In each BMD category (osteoporosis, osteopenia, normal BMD), fracture incidence was two to three times higher in women with SFS ≥70 than <70. In multivariable analyses, associations with fractures remained for BMD and SFS, not FRAX. BMD was no longer, or weakly, associated with fractures after accounting for SFS, whereas SFS remained associated with fracture after accounting for BMD. SFS detected two-to threefold more women having fractures than BMD or FRAX. SFS in women with osteopenia/normal BMD conferred an odds ratio for fracture of 2.69 to 5.19 for women of any age and 4.98 to 12.2 for women ≥70 years. Receiver-operator curve (ROC) analyses showed a significant area under the curve (AUC) for SFS, but not BMD or FRAX for the women ≥70 years of age. Targeting women aged ≥70 years with osteopenia indicated that treating 25% using SFS to allocate treatment conferred a cost-effectiveness ratio < USD $21,000/QALY saved. Quantifying microstructural deterioration complements BMD by identifying women without osteoporosis at imminent and longer-term fracture risk. © 2019 American Society for Bone and Mineral Research.
Asunto(s)
Enfermedades Óseas Metabólicas , Fracturas Óseas , Osteoporosis , Fracturas Osteoporóticas , Adulto , Anciano , Anciano de 80 o más Años , Densidad Ósea , Enfermedades Óseas Metabólicas/diagnóstico por imagen , Enfermedades Óseas Metabólicas/epidemiología , Niño , Preescolar , Femenino , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/epidemiología , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo , Factores de RiesgoRESUMEN
Previous studies have shown that microdamage accumulates in bone as a result of physiological loading and occurs naturally in human trabecular bone. The purpose of this study was to determine the factors associated with pre-existing microdamage in human vertebral trabecular bone, namely age, architecture, hardness, mineral and organic matrix. Trabecular bone cores were collected from human L2 vertebrae (nâ=â53) from donors 54-95 years of age (22 men and 30 women, 1 unknown) and previous cited parameters were evaluated. Collagen cross-link content (PYD, DPD, PEN and % of collagen) was measured on surrounding trabecular bone. We found that determinants of microdamage were mostly the age of donors, architecture, mineral characteristics and mature enzymatic cross-links. Moreover, linear microcracks were mostly associated with the bone matrix characteristics whereas diffuse damage was associated with architecture. We conclude that linear and diffuse types of microdamage seemed to have different determinants, with age being critical for both types.
Asunto(s)
Columna Vertebral/química , Columna Vertebral/patología , Factores de Edad , Anciano , Anciano de 80 o más Años , Densidad Ósea , Calcificación Fisiológica , Colágeno/análisis , Femenino , Dureza , Humanos , Masculino , Persona de Mediana Edad , Minerales/análisis , Columna Vertebral/ultraestructuraRESUMEN
This 2-year trial evaluated the efficacy and tolerability of a monthly oral regimen of risedronate. Postmenopausal women with osteoporosis were randomly assigned to double-blind treatment with risedronate 75 mg on 2 consecutive days each month (2CDM) or 5 mg daily. The primary end point was the percentage change from baseline in lumbar spine bone mineral density (BMD) at 12 months. Secondary end points included the change in BMD of the lumbar spine and proximal femur and in bone turnover markers as well as the number of subjects with at least one new vertebral fracture over 24 months. Among 1,229 patients who were randomized and received at least one dose of risedronate, lumbar spine BMD was increased in both treatment groups: mean percentage change from baseline was 4.2 ± 0.19 and 4.3 ± 0.19 % in the 75 mg 2CDM and 5 mg daily groups, respectively, at month 24. The treatment difference was 0.17 (95 % confidence interval -0.35 to 0.68). There were no statistically significant differences between treatment groups on any secondary efficacy parameters. Both treatment regimens were well tolerated. Risedronate 75 mg 2CDM was noninferior in BMD efficacy and did not show a difference in tolerability compared to 5 mg daily after 24 months of treatment in women with postmenopausal osteoporosis. This monthly regimen may provide a more convenient dosing schedule to some patients with postmenopausal osteoporosis.
Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Ácido Etidrónico/análogos & derivados , Osteoporosis Posmenopáusica/tratamiento farmacológico , Anciano , Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Método Doble Ciego , Esquema de Medicación , Ácido Etidrónico/administración & dosificación , Femenino , Humanos , Vértebras Lumbares/efectos de los fármacos , Persona de Mediana Edad , Seguridad del Paciente , Proyectos de Investigación , Ácido Risedrónico , Fracturas de la Columna Vertebral/prevención & control , Resultado del TratamientoRESUMEN
OBJECTIVES: High resolution peripheral quantitative tomography (HR-pQCT) is used more widely to assess microarchitecture, but we are lacking comparisons between HR-pQCT and histomorphometry, which is considered the gold standard. They have only been assessed on different anatomical regions. The purpose of our study was to assess the microarchitecture and the relative contribution of cortical and trabecular bone in hip fracture with this 3D imaging technique, compared with the 2D histomorphometry. MATERIAL AND METHODS: We compared the distribution of cortical and trabecular bone in the ultradistal femoral neck samples (~3mm thick) obtained after total hip replacement in 21 hip osteoarthritis (HOA, 66±8yrs) and 20 hip fracture (HF, 79±8yrs) menopausal women by a direct 3D evaluation method (HR-pQCT: XtremeCT, Scanco Medical AG) and by histomorphometry, performed and averaged on three 10µm-thick sections 800µm apart. RESULTS: Significant correlations were found between both techniques for trabecular bone volume, number, thickness, separation and cortical thickness (0.51Asunto(s)
Huesos/anatomía & histología
, Fracturas de Cadera/patología
, Osteoartritis de la Cadera/patología
, Posmenopausia
, Anciano
, Anciano de 80 o más Años
, Huesos/patología
, Femenino
, Fracturas de Cadera/cirugía
, Humanos
, Persona de Mediana Edad
RESUMEN
The purpose of this study was to adapt various staining methods for the detection of microdamage in human bone, while preserving tetracycline labels. We describe two staining methods using calcein green and xylenol orange, first developed in ewe bone samples and validated in human trabecular bone samples. In ewe bones, we found that calcein green at 0.5 mM concentration diluted in 100% ethanol as well as xylenol orange at 5 mM were the most adequate fluorochromes both to detect microdamage and preserve the double tetracycline labeling. These results were verified in human trabecular bone (iliac crest for the tetracycline label, and vertebral bone for the double labeling). Results obtained in human bone samples were identical to those in ewes, so this combination of fluorochromes is now used in our laboratory.
Asunto(s)
Huesos/química , Colorantes Fluorescentes/química , Coloración y Etiquetado/métodos , Animales , Humanos , OvinosRESUMEN
Few studies have investigated bone microarchitecture and biomechanical properties in men. This study assessed in vivo both aspects in a population of 185 men (aged 71 ± 10 years) with prevalent fragility fractures, compared to 185 controls matched for age, height, and weight, from the Structure of the Aging Men's Bones (STRAMBO) cohort. In this case-control study, areal BMD (aBMD) was measured by DXA, bone microarchitecture was assessed by high resolution (HR)-pQCT, and finite element (µFE) analysis was based on HR-pQCT images of distal radius and tibia. A principal component (PC) analysis (PCA) was used to study the association of synthetic PCs with fracture by computing their odds ratio (OR [95%CI]) per SD change. Specific associations with vertebral fracture (n = 100), and nonvertebral fracture (n = 85) were also computed. At both sites, areal and volumetric BMD, cortical thickness and trabecular number, separation, and distribution were significantly worse in cases than in controls, with differences ranging from -6% to 15%. µFE-derived stiffness and failure load were 8% to 9% lower in fractures (p < .01). No difference in load distribution was found between the two groups. After adjustment for aBMD, only differences of µFE-derived stresses, stiffness, and failure load at the tibia remained significant (p < .05). PCA resulted in defining 4 independent PCs, explaining 83% of the total variability of bone characteristics. Nonvertebral fractures were associated with PC1, reflecting bone quantity and strength at the radius (tibia) with OR = 1.64 [1.27-2.12] (2.21 [1.60-3.04]), and with PC2, defined by trabecular microarchitecture, with OR = 1.27 [1.00-1.61]. Severe vertebral fractures were associated with PC1, with OR = 1.56 [1.16-2.09] (2.21 [1.59-3.07]), and with PC2, with OR = 1.55 [1.17-2.06] (1.45 [1.06-1.98]). In conclusion, microarchitecture and biomechanical properties derived from µFE were associated with all types of fractures in men, showing that radius and tibia mechanical properties were relatively representative of distant bone site properties.
Asunto(s)
Análisis de Elementos Finitos , Fracturas Óseas/diagnóstico por imagen , Radio (Anatomía)/diagnóstico por imagen , Radio (Anatomía)/patología , Tibia/diagnóstico por imagen , Tibia/patología , Tomografía Computarizada por Rayos X , Adulto , Anciano , Análisis de Varianza , Fenómenos Biomecánicos , Densidad Ósea , Fracturas Óseas/patología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Análisis de Componente Principal , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/patología , Fracturas de la Columna Vertebral/fisiopatología , Estrés Mecánico , Adulto JovenRESUMEN
Areal bone mineral density (aBMD) measured by dual-energy X-ray absorptiometry (DXA) identifies 20% of men who will sustain fragility fractures. Thus we need better fracture predictors in men. We assessed the association between the low-trauma prevalent fractures and bone microarchitecture assessed at the distal radius and tibia by high-resolution peripheral quantitative computed tomography (HR-pQCT) in 920 men aged 50 years of older. Ninety-eight men had vertebral fractures identified on the vertebral fracture assessment software of the Hologic Discovery A device using the semiquantitative criteria, whereas 100 men reported low-trauma peripheral fractures. Men with vertebral fractures had poor bone microarchitecture. However, in the men with vertebral fractures, only cortical volumetric density (D.cort) and cortical thickness (C.Th) remained significantly lower at both the radius and tibia after adjustment for aBMD of ultradistal radius and hip, respectively. Low D.cort and C.Th were associated with higher prevalence of vertebral fractures regardless of aBMD. Severe vertebral fractures also were associated with poor trabecular microarchitecture regardless of aBMD. Men with peripheral fractures had poor bone microarchitecture. However, after adjustment for aBMD, all microarchitectural parameters became nonsignificant. In 15 men with multiple peripheral fractures, trabecular spacing and distribution remained increased after adjustment for aBMD. Thus, in men, vertebral fractures and their severity are associated with impaired cortical bone, even after adjustment for aBMD. The association between peripheral fractures and bone microarchitecture was weaker and nonsignificant after adjustment for aBMD. Thus bone microarchitecture may be a determinant of bone fragility in men, which should be investigated in prospective studies.
Asunto(s)
Envejecimiento/patología , Huesos/patología , Fracturas Óseas/patología , Anciano , Densidad Ósea/fisiología , Estudios de Cohortes , Estudios Transversales , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/epidemiología , Fracturas Óseas/fisiopatología , Francia/epidemiología , Humanos , Masculino , Prevalencia , Radiografía , Radio (Anatomía)/diagnóstico por imagen , Radio (Anatomía)/patología , Radio (Anatomía)/fisiopatología , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/patología , Columna Vertebral/fisiopatología , Tibia/diagnóstico por imagen , Tibia/patología , Tibia/fisiopatologíaRESUMEN
PURPOSE: To determine if important geographic differences exist in treatment rates for osteoporosis and whether this variation can be explained by regional variation in risk factors. METHODS: The Global Longitudinal Study of Osteoporosis in Women is an observational study of women ≥55 years sampled from primary care practices in 10 countries. Self-administered questionnaires were used to collect data on patient characteristics, risk factors for fracture, previous fractures, anti-osteoporosis medication, and health status. RESULTS: Among 58,009 women, current anti-osteoporosis medication use was lowest in Northern Europe (16%) and highest in U.S.A. and Australia (32%). Between 48% (U.S.A., Southern Europe) and 68% (Northern Europe) of women aged ≥65 years with a history of spine or hip fracture since age 45 were untreated. Among women with osteoporosis, the percentage of treated cases was lowest in Europe (45-52% versus 62-65% elsewhere). Women with osteopenia and no other risk factors were treated with anti-osteoporosis medication most frequently in U.S.A. (31%) and Canada (31%), and least frequently in Southern Europe (12%), Northern Europe (13%), and Australia (16%). After adjusting for risk factors, U.S. women were threefold as likely to be treated with anti-osteoporosis medication as Northern European women (odds ratio 2.8; 95% confidence interval 2.5-3.1) and 1.5 times as likely to be treated as Southern European women (1.5, 1.4-1.6). Up to half of women reporting previous hip or spine fracture did not receive treatment. CONCLUSIONS: The likelihood of being treated for osteoporosis differed between regions, and cannot be explained by variation in risk factors. Many women at risk of fracture do not receive prophylaxis.
Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Osteoporosis/tratamiento farmacológico , Anciano , Australia , Canadá , Terapia de Reemplazo de Estrógeno , Europa (Continente) , Femenino , Fracturas Óseas/etiología , Fracturas Óseas/prevención & control , Estado de Salud , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Osteoporosis/complicaciones , Factores de Riesgo , Encuestas y Cuestionarios , Estados UnidosRESUMEN
The ability of a vertebra to carry load after an initial deformation and the determinants of this postfracture load-bearing capacity are critical but poorly understood. This study aimed to determine the mechanical behavior of vertebrae after simulated mild fracture and to identify the determinants of this postfracture behavior. Twenty-one human L(3) vertebrae were analyzed for bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) and for microarchitecture by micro-computed tomography (µCT). Mechanical testing was performed in two phases: initial compression of vertebra to 25% deformity, followed, after 30 minutes of relaxation, by a similar test to failure to determine postfracture behavior. We assessed (1) initial and postfracture mechanical parameters, (2) changes in mechanical parameters, (3) postfracture elastic behavior by recovery of vertebral height after relaxation, and (4) postfracture plastic behavior by residual strength and stiffness. Postfracture failure load and stiffness were 11% ± 19% and 53% ± 18% lower than initial values (p = .021 and p < .0001, respectively), with 29% to 69% of the variation in the postfracture mechanical behavior explained by the initial values. Both initial and postfracture mechanical behaviors were significantly correlated with bone mass and microarchitecture. Vertebral deformation recovery averaged 31% ± 7% and was associated with trabecular and cortical thickness (r = 0.47 and r = 0.64; p = .03 and p = .002, respectively). Residual strength and stiffness were independent of bone mass and initial mechanical behavior but were related to trabecular and cortical microarchitecture (|r| = 0.50 to 0.58; p = .02 to .006). In summary, we found marked variation in the postfracture load-bearing capacity following simulated mild vertebral fractures. Bone microarchitecture, but not bone mass, was associated with postfracture mechanical behavior of vertebrae.
Asunto(s)
Fracturas por Compresión , Vértebras Lumbares/anatomía & histología , Vértebras Lumbares/química , Fenómenos Mecánicos , Absorciometría de Fotón , Factores de Edad , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Densidad Ósea , Fuerza Compresiva , Elasticidad , Femenino , Dureza , Humanos , Masculino , Persona de Mediana Edad , Caracteres Sexuales , Microtomografía por Rayos XRESUMEN
Previous studies have shown that the mechanical properties of trabecular bone are determined by bone volume fraction (BV/TV) and microarchitecture. The purpose of this study was to explore other possible determinants of the mechanical properties of vertebral trabecular bone, namely collagen cross-link content, microdamage, and mineralization. Trabecular bone cores were collected from human L2 vertebrae (n = 49) from recently deceased donors 54-95 years of age (21 men and 27 women). Two trabecular cores were obtained from each vertebra, one for preexisting microdamage and mineralization measurements, and one for BV/TV and quasi-static compression tests. Collagen cross-link content (PYD, DPD, and PEN) was measured on surrounding trabecular bone. Advancing age was associated with impaired mechanical properties, and with increased microdamage, even after adjustment by BV/TV. BV/TV was the strongest determinant of elastic modulus and ultimate strength (r² = 0.44 and 0.55, respectively). Microdamage, mineralization parameters, and collagen cross-link content were not associated with mechanical properties. These data indicate that the compressive strength of human vertebral trabecular bone is primarily determined by the amount of trabecular bone, and notably unaffected by normal variation in other factors, such as cross-link profile, microdamage and mineralization.
Asunto(s)
Calcificación Fisiológica/fisiología , Colágeno/metabolismo , Reactivos de Enlaces Cruzados/metabolismo , Vértebras Lumbares/patología , Anciano , Anciano de 80 o más Años , Aminoácidos/metabolismo , Arginina/análogos & derivados , Arginina/metabolismo , Biomarcadores/metabolismo , Fuerza Compresiva , Femenino , Humanos , Vértebras Lumbares/metabolismo , Lisina/análogos & derivados , Lisina/metabolismo , Masculino , Persona de Mediana Edad , Estrés Mecánico , Soporte de PesoRESUMEN
Bone microarchitecture can be studied noninvasively using high-resolution peripheral quantitative computed tomography (HR-pQCT). However, this technique is not widely available, so more simple techniques may be useful. BMA is a new 2D high-resolution digital X-ray device, allowing for bone texture analysis with a fractal parameter (H(mean)). The aims of this study were (1) to evaluate the reproducibility of BMA at two novel sites (radius and tibia) in addition to the conventional site (calcaneus), (2) to compare the results obtained with BMA at all of those sites, and (3) to study the relationship between H(mean) and trabecular microarchitecture measured with an in vivo 3D device (HR-pQCT) at the distal tibia and radius. BMA measurements were performed at three sites (calcaneus, distal tibia, and radius) in 14 healthy volunteers to measure the short-term reproducibility and in a group of 77 patients with chronic kidney disease to compare BMA results to HR-pQCT results. The coefficient of variation of H(mean) was 1.2, 2.1, and 4.7% at the calcaneus, radius, and tibia, respectively. We found significant associations between trabecular volumetric bone mineral density and microarchitectural variables measured by HR-pQCT and H(mean) at the three sites (e.g., Pearson correlation between radial trabecular number and radial H(mean) r = 0.472, P < 0.001). This study demonstrated a significant but moderate relationship between 2D bone texture and 3D trabecular microarchitecture. BMA is a new reproducible technique with few technical constraints. Thus, it may represent an interesting tool for evaluating bone structure, in association with biological parameters and DXA.
Asunto(s)
Fallo Renal Crónico/complicaciones , Osteoporosis/diagnóstico por imagen , Radio (Anatomía)/diagnóstico por imagen , Tibia/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Absorciometría de Fotón/métodos , Adulto , Anciano , Anciano de 80 o más Años , Densidad Ósea/fisiología , Calcáneo/diagnóstico por imagen , Calcáneo/patología , Estudios Transversales , Femenino , Humanos , Fallo Renal Crónico/diagnóstico por imagen , Fallo Renal Crónico/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteoporosis/patología , Radio (Anatomía)/patología , Tibia/patología , Adulto JovenRESUMEN
The relationship between bisphosphonate-induced bone mineral density (BMD) gains and antifracture efficacy remains to be fully elucidated. Data from two antifracture studies were analyzed. Postmenopausal osteoporotic women received oral (2.5 mg daily, 20 mg intermittent) or intravenous (0.5 mg, 1 mg quarterly) ibandronate. Outcome measures included moving averages plots and logistic regression analyses of the relationship between BMD change and vertebral fracture rate. In moving averages plots, ibandronate-induced BMD gains were consistently associated with decreased fracture rates. In the oral study, total-hip BMD increases at years 2 and 3 and lumbar spine BMD increases at year 3 were associated with 3-year vertebral fracture rate (relative risk reduction [RRR] at year 3 for 1% change from baseline: hip, 7.9% [95% CI 2.1-13.5%, P = 0.0084]; lumbar spine, 4.7% [-0.1% to 9.3%, P = 0.0565]). In the intravenous study, total-hip BMD increases at years 1, 2, and 3 and lumbar spine BMD increases at years 2 and 3 were significantly associated with vertebral fracture rate (RRR at year 3 for 1% change from baseline: hip, 11.6% [7.0-16.0%, P < 0.0001]; lumbar spine, 6.9% [2.9-10.6%, P = 0.0008]). In a pooled analysis, changes in total-hip and lumbar spine BMD were associated with 3-year vertebral fracture risk reduction and explained a substantial proportion of the antifracture effect (23-37% at 2 and 3 years). This analysis suggests that ibandronate-induced BMD gain in postmenopausal osteoporotic women is associated with vertebral fracture risk reduction.
Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Densidad Ósea/efectos de los fármacos , Difosfonatos/uso terapéutico , Articulación de la Cadera/efectos de los fármacos , Vértebras Lumbares/efectos de los fármacos , Fracturas de la Columna Vertebral/prevención & control , Administración Oral , Anciano , Anciano de 80 o más Años , Femenino , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/metabolismo , Humanos , Ácido Ibandrónico , Inyecciones Intravenosas , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/metabolismo , Persona de Mediana Edad , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/metabolismo , Radiografía , Fracturas de la Columna Vertebral/complicaciones , Fracturas de la Columna Vertebral/metabolismoRESUMEN
OBJECTIVE: To examine several dimensions of health-related quality of life (HRQL) in postmenopausal women who report previous fractures, and to provide perspective by comparing these findings with those in other chronic conditions (diabetes, arthritis, lung disease). PATIENTS AND METHODS: Fractures are a major cause of morbidity among older women. Few studies have examined HRQL in women who have had prior fractures and the effect of prior fracture location on HRQL. In this observational study of 57,141 postmenopausal women aged 55 years and older (enrollment from December 2007 to March 2009) from 17 study sites in 10 countries, HRQL was measured using the European Quality of Life 5 Dimensions Index (EQ-5D) and the health status, physical function, and vitality questions of the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36). RESULTS: Reductions in EQ-5D health-utility scores and SF-36-measured health status, physical function, and vitality were seen in association with 9 of 10 fracture locations. Spine, hip, and upper leg fractures resulted in the greatest reductions in quality of life (EQ-5D scores, 0.62, 0.64, and 0.61, respectively, vs 0.79 without prior fracture). Women with fractures at any of these 3 locations, as well as women with a history of multiple fractures (EQ-5D scores, 0.74 for 1 prior fracture, 0.68 for 2, and 0.58 for >/=3), had reductions in HRQL that were similar to or worse than those in women with other chronic diseases (0.67 for diabetes, 0.69 for arthritis, and 0.71 for lung disease). CONCLUSION: Previous fractures at a variety of bone locations, particularly spine, hip, and upper leg, or involving more than 1 location are associated with significant reductions in quality of life.
Asunto(s)
Fracturas Óseas/psicología , Osteoporosis/complicaciones , Calidad de Vida , Factores de Edad , Anciano , Europa (Continente) , Femenino , Fracturas del Fémur/etiología , Fracturas del Fémur/psicología , Fracturas Óseas/etiología , Estado de Salud , Fracturas de Cadera/etiología , Fracturas de Cadera/psicología , Humanos , Modelos Lineales , Estudios Longitudinales , Persona de Mediana Edad , Osteoporosis/psicología , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/psicologíaRESUMEN
Low bone mineral density (BMD) is a strong risk factor for vertebral fracture risk in osteoporosis. However, many fractures occur in people with moderately decreased or normal BMD. Our aim was to assess the contributions of trabecular microarchitecture and its heterogeneity to the mechanical behavior of human lumbar vertebrae. Twenty-one human L(3) vertebrae were analyzed for BMD by dual-energy X-ray absorptiometry (DXA) and microarchitecture by high-resolution peripheral quantitative computed tomography (HR-pQCT) and then tested in axial compression. Microarchitecture heterogeneity was assessed using two vertically oriented virtual biopsies--one anterior (Ant) and one posterior (Post)--each divided into three zones (superior, middle, and inferior) and using the whole vertebral trabecular volume for the intraindividual distribution of trabecular separation (Tb.Sp*SD). Heterogeneity parameters were defined as (1) ratios of anterior to posterior microarchitectural parameters and (2) the coefficient of variation of microarchitectural parameters from the superior, middle, and inferior zones. BMD alone explained up to 44% of the variability in vertebral mechanical behavior, bone volume fraction (BV/TV) up to 53%, and trabecular architecture up to 66%. Importantly, bone mass (BMD or BV/TV) in combination with microarchitecture and its heterogeneity improved the prediction of vertebral mechanical behavior, together explaining up to 86% of the variability in vertebral failure load. In conclusion, our data indicate that regional variation of microarchitecture assessment expressed by heterogeneity parameters may enhance prediction of vertebral fracture risk.
Asunto(s)
Vértebras Lumbares/anatomía & histología , Vértebras Lumbares/fisiología , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos/fisiología , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Modelos Biológicos , Tamaño de los Órganos , Análisis de Regresión , Tomografía Computarizada por Rayos XRESUMEN
The structural basis of the antifracture efficacy of strontium ranelate and alendronate is incompletely understood. We compared the effects of strontium ranelate and alendronate on distal tibia microstructure over 2 years using HR-pQCT. In this pre-planned, interim, intention-to-treat analysis at 12 months, 88 osteoporotic postmenopausal women (mean age 63.7 +/- 7.4) were randomized to strontium ranelate 2 g/day or alendronate 70 mg/week in a double-placebo design. Primary endpoints were changes in microstructure. Secondary endpoints included lumbar and hip areal bone mineral density (aBMD), and bone turnover markers. This trial is registered with http://www.controlled-trials.com, number ISRCTN82719233. Baseline characteristics of the two groups were similar. Treatment with strontium ranelate was associated with increases in mean cortical thickness (CTh, 5.3%), cortical area (4.9%) and trabecular density (2.1%) (all P < 0.001, except cortical area P = 0.013). No significant changes were observed with alendronate. Between-group differences in favor of strontium ranelate were observed for CTh, cortical area, BV/TV and trabecular density (P = 0.045, 0.041, 0.048 and 0.035, respectively). aBMD increased to a similar extent with strontium ranelate and alendronate at the spine (5.7% versus 5.1%, respectively) and total hip (3.3% versus 2.2%, respectively). No significant changes were observed in remodeling markers with strontium ranelate, while suppression was observed with alendronate. Within the methodological constraints of HR-pQCT through its possible sensitivity to X-ray attenuation of different minerals, strontium ranelate had greater effects than alendronate on distal tibia cortical thickness and trabecular volumetric density.
Asunto(s)
Alendronato/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Compuestos Organometálicos/uso terapéutico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Tiofenos/uso terapéutico , Tibia/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Femenino , Cuello Femoral/diagnóstico por imagen , Cuello Femoral/efectos de los fármacos , Cuello Femoral/metabolismo , Fracturas Óseas/prevención & control , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/efectos de los fármacos , Articulación de la Cadera/metabolismo , Humanos , Persona de Mediana Edad , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Osteoporosis Posmenopáusica/metabolismo , Osteoporosis Posmenopáusica/patología , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/efectos de los fármacos , Columna Vertebral/metabolismo , Tibia/patología , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVES: A new high-resolution peripheral quantitative CT (HR-pQCT) system allows for in vivo assessment of bone microarchitecture and volumetric bone mineral density (vBMD) with an 82 microm isotropic resolution. With this device, the microarchitecture impairment was evaluated in patients with rheumatoid arthritis (RA) in comparison with healthy controls and measured the erosion volume at metacarpal heads (MCPs). METHODS: In this cross-sectional study, the reproducibility was first assessed by 3 HR-pQCT exams with repositioning in 14 patients with late RA and 14 healthy subjects. Then, HR-pQCT parameters were measured in a group of 93 patients with RA and 31 healthy controls. Two RA subgroups were distinguished: early RA (disease duration < or =2 years) (n=36) and late RA (n=57) and compared them to healthy controls. RESULTS: The precision of the HR-pQCT volumetric measurements as assessed with coefficient of variation ranged from 0.7% to 1.8% in patients with late RA and from 0.6% to 1.4% in healthy subjects at MCPs. Total and trabecular vBMD and trabecular thickness were significantly decreased in patients with RA compared to healthy subjects and were significantly correlated to disease activity. The erosion volume was highly correlated to a semiquantitative assessment using the Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT) scoring system applied to the HR-pQCT slices. CONCLUSIONS: This study demonstrated the good reproducibility of the HR-pQCT volumetric measurements at MCPs and confirmed the involvement of trabecular compartment in periarticular osteopoenia. Thus, HR-pQCT appears interesting to simultaneously assess differences in bone volumetric density, microarchitecture and erosions.
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Artritis Reumatoide/complicaciones , Enfermedades Óseas Metabólicas/etiología , Huesos del Metacarpo/diagnóstico por imagen , Adulto , Artritis Reumatoide/fisiopatología , Densidad Ósea , Enfermedades Óseas Metabólicas/diagnóstico por imagen , Enfermedades Óseas Metabólicas/fisiopatología , Estudios Transversales , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Huesos del Metacarpo/fisiopatología , Persona de Mediana Edad , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X , Adulto JovenRESUMEN
The FRAX tool estimates an individual's fracture probability over 10 years from clinical risk factors with or without bone mineral density (BMD) measurement. The aim of our study was to compare the predicted fracture probabilities and the observed incidence of fracture in French women during a 10-year follow-up. The probabilities of fracture at four major sites (hip, clinical spine, shoulder, or wrist) and at the hip were calculated with the FRAX tool in 867 women aged 40 years and over from the Os des Femmes de Lyon (OFELY) cohort.The incidence of fracture was observed over 10 years. Thus 82 women sustained 95 incident major osteoporotic (OP) fractures including 17 fractures at the hip. In women aged at least 65 years (n = 229), the 10-year predicted probabilities of fracture with BMD were 13% for major OP fractures and 5% for hip fractures, contrasting with 3.6% and 0.5% in women younger than 65 years (p < .0001). The predicted probabilities of both major OP and hip fractures were significantly higher in women with osteoporosis (n = 77, 18% and 10%) and osteopenia (n = 390, 6% and 2%) compared with women with normal BMD (n = 208, 3% and <1%; p < .0001. The predicted probabilities of fracture were two and five times higher in women who sustained an incident major OP fracture and a hip fracture compared with women who did not (p < .0001). Nevertheless, among women aged at least 65 years with low BMD values (T-score < or = -1; n = 199), the 10-year predicted probability of major OP fracture with BMD was 48% lower than the observed incidence of fractures (p < .01). A 10-year probability of major OP fracture higher than 12% identified more women with incident fractures than did BMD in the osteoporotic range (p < .05). In French women from the OFELY cohort, the observed incidence of fragility fractures over 10 years increased with age following a pattern similar to the predicted probabilities given by the FRAX tool. However, in women aged at least 65 years with low BMD, the observed incidence of fractures was substantially higher than the predicted probability.
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Fracturas Óseas/epidemiología , Adulto , Anciano , Estudios de Cohortes , Femenino , Francia/epidemiología , Humanos , Incidencia , Persona de Mediana Edad , ProbabilidadRESUMEN
Few data concern the relationship between bone turnover and microarchitecture in men. We investigated the association between levels of biochemical markers of bone turnover (BTM) and bone microarchitecture in 1149 men aged 19 to 85 years. Bone microarchitecture was assessed by high-resolution peripheral quantitative computed tomography at the distal radius and tibia. Bone formation was assessed by serum osteocalcin, bone alkaline phosphatase, and N-terminal extension propeptide of type I collagen. Bone resorption was assessed by serum C-terminal telopeptide of type I collagen and urinary excretion of total deoxypyridinoline. BTM levels were high in young men and decreased until age 50 years. Urinary deoxypyridinoline (DPD) increased after age 70 years, whereas other BTMs remained stable. Before 50 years of age, only cortical volumetric bone mineral density (D(cort)) correlated negatively with BTM levels. Between 50 and 70 years of age, D(cort) and some microarchitectural parameters correlated significantly with BTM at the radius and tibia. After 70 years of age, higher BTM levels were associated with lower cortical thickness and D(cort) at both the skeletal sites. At the distal radius, men in the highest BTM quartile had lower trabecular density, number (Tb.N), and thickness (Tb.Th) and more heterogeneous trabecular distribution compared with men in the lower quartiles. At the distal tibia, higher BTM levels were associated with lower Tb.N and Tb.Th in the central but not subendocortical area. Thus, in men, bone microarchitecture depends weakly on the current bone turnover rate until age 70. Thereafter, bone turnover seems to be a significant determinant of bone microarchitecture.
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Remodelación Ósea/fisiología , Huesos/anatomía & histología , Huesos/fisiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Biomarcadores/sangre , Biomarcadores/orina , Resorción Ósea/sangre , Resorción Ósea/patología , Resorción Ósea/fisiopatología , Resorción Ósea/orina , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Osteogénesis/fisiología , Radio (Anatomía)/anatomía & histología , Radio (Anatomía)/fisiopatología , Tibia/anatomía & histología , Tibia/fisiopatología , Adulto JovenRESUMEN
Inflammatory related hand bone damage in rheumatoid arthritis is characterized by erosions and periarticular osteoporosis and can lead to substantial clinical disability. So far, conventional radiograph has been considered to be the gold standard for detecting bone damage and monitoring disease progression, but it lacks sensitivity. So other techniques have been recently developed to identify erosions earlier, to be able to change therapy; if necessary. This report reviews, in its first part, the different ways of detecting erosions such as conventional radiograph, magnetic resonance imaging or imaging ultrasonography and, in its second part, the techniques used for the assessment of hand periarticular osteoporosis like dual-X-ray absorptiometry, digital-X-ray radiogrammetry or quantitative ultrasonography.
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Artritis Reumatoide/diagnóstico , Densidad Ósea , Mano , Absorciometría de Fotón , Artritis Reumatoide/fisiopatología , Artrografía , Progresión de la Enfermedad , Humanos , Imagen por Resonancia Magnética , UltrasonografíaRESUMEN
BACKGROUND: Changes in body composition underlying the association between weight loss and higher mortality are not clear. OBJECTIVE: The objective was to investigate the association between changes in body composition of the appendicular (4 limbs) and central (trunk) compartments and all-cause mortality in men. DESIGN: In men aged > or = 50 y, body composition was assessed every 18 mo for 7.5 y with a whole-body dual-energy X-ray absorptiometry scan. Mortality was assessed for 10 y. Data were analyzed by logistic regression and Cox model and adjusted for age, body mass index (BMI), educational level, lifestyle, physical performance, comorbidities, body composition, and serum concentrations of 17beta-estradiol and 25-hydroxycholecalciferol. RESULTS: Of 715 men who were followed up, 137 (19.2%) died. Mortality was higher in men with the fastest weight loss [lowest compared with middle tertile odds ratio (OR): 2.31; 99% CI: 1.05, 5.09]. Faster loss of appendicular skeletal muscle mass (ASMM) was predictive of mortality (lowest compared with middle tertile OR: 3.60; 99% CI: 1.64, 7.89). Faster loss in ASMM remained a strong predictor of mortality after adjustment for weight loss (OR: 3.41; 99% CI: 1.51, 7.71). Faster loss in ASMM was the strongest predictor of death in the stepwise procedures when it was analyzed jointly with changes in the mass of other compartments. Loss in ASMM calculated over 36 mo was also a stronger predictor of death than were changes in the mass of other compartments (hazard ratio: 1.33 per 1-SD decrease; 95% CI: 1.06, 1.66). CONCLUSION: The accelerated loss of ASMM is predictive of all-cause mortality in older men regardless of age, BMI, lifestyle, physical performance, health status, body composition, and serum 17beta-estradiol and 25-hydroxycholecalciferol.