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1.
Osteoporos Int ; 34(12): 2027-2045, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37566158

RESUMO

A large international meta-analysis using primary data from 64 cohorts has quantified the increased risk of fracture associated with a previous history of fracture for future use in FRAX. INTRODUCTION: The aim of this study was to quantify the fracture risk associated with a prior fracture on an international basis and to explore the relationship of this risk with age, sex, time since baseline and bone mineral density (BMD). METHODS: We studied 665,971 men and 1,438,535 women from 64 cohorts in 32 countries followed for a total of 19.5 million person-years. The effect of a prior history of fracture on the risk of any clinical fracture, any osteoporotic fracture, major osteoporotic fracture, and hip fracture alone was examined using an extended Poisson model in each cohort. Covariates examined were age, sex, BMD, and duration of follow-up. The results of the different studies were merged by using the weighted ß-coefficients. RESULTS: A previous fracture history, compared with individuals without a prior fracture, was associated with a significantly increased risk of any clinical fracture (hazard ratio, HR = 1.88; 95% CI = 1.72-2.07). The risk ratio was similar for the outcome of osteoporotic fracture (HR = 1.87; 95% CI = 1.69-2.07), major osteoporotic fracture (HR = 1.83; 95% CI = 1.63-2.06), or for hip fracture (HR = 1.82; 95% CI = 1.62-2.06). There was no significant difference in risk ratio between men and women. Subsequent fracture risk was marginally downward adjusted when account was taken of BMD. Low BMD explained a minority of the risk for any clinical fracture (14%), osteoporotic fracture (17%), and for hip fracture (33%). The risk ratio for all fracture outcomes related to prior fracture decreased significantly with adjustment for age and time since baseline examination. CONCLUSION: A previous history of fracture confers an increased risk of fracture of substantial importance beyond that explained by BMD. The effect is similar in men and women. Its quantitation on an international basis permits the more accurate use of this risk factor in case finding strategies.


Assuntos
Fraturas do Quadril , Osteoporose , Fraturas por Osteoporose , Masculino , Humanos , Feminino , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/complicações , Osteoporose/complicações , Fraturas do Quadril/etiologia , Fraturas do Quadril/complicações , Densidade Óssea , Fatores de Risco , Medição de Risco
2.
Osteoporos Int ; 33(10): 2103-2136, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35639106

RESUMO

We describe the collection of cohorts together with the analysis plan for an update of the fracture risk prediction tool FRAX with respect to current and novel risk factors. The resource comprises 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures. INTRODUCTION: The availability of the fracture risk assessment tool FRAX® has substantially enhanced the targeting of treatment to those at high risk of fracture with FRAX now incorporated into more than 100 clinical osteoporosis guidelines worldwide. The aim of this study is to determine whether the current algorithms can be further optimised with respect to current and novel risk factors. METHODS: A computerised literature search was performed in PubMed from inception until May 17, 2019, to identify eligible cohorts for updating the FRAX coefficients. Additionally, we searched the abstracts of conference proceedings of the American Society for Bone and Mineral Research, European Calcified Tissue Society and World Congress of Osteoporosis. Prospective cohort studies with data on baseline clinical risk factors and incident fractures were eligible. RESULTS: Of the 836 records retrieved, 53 were selected for full-text assessment after screening on title and abstract. Twelve cohorts were deemed eligible and of these, 4 novel cohorts were identified. These cohorts, together with 60 previously identified cohorts, will provide the resource for constructing an updated version of FRAX comprising 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures. For each known and candidate risk factor, multivariate hazard functions for hip fracture, major osteoporotic fracture and death will be tested using extended Poisson regression. Sex- and/or ethnicity-specific differences in the weights of the risk factors will be investigated. After meta-analyses of the cohort-specific beta coefficients for each risk factor, models comprising 10-year probability of hip and major osteoporotic fracture, with or without femoral neck bone mineral density, will be computed. CONCLUSIONS: These assembled cohorts and described models will provide the framework for an updated FRAX tool enabling enhanced assessment of fracture risk (PROSPERO (CRD42021227266)).


Assuntos
Fraturas do Quadril , Osteoporose , Fraturas por Osteoporose , Densidade Óssea , Fraturas do Quadril/complicações , Fraturas do Quadril/etiologia , Humanos , Osteoporose/complicações , Osteoporose/epidemiologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Estudos Prospectivos , Medição de Risco/métodos , Fatores de Risco
3.
Osteoporos Int ; 31(6): 1025-1048, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32335687

RESUMO

The surgeon general of the USA defines osteoporosis as "a skeletal disorder characterized by compromised bone strength, predisposing to an increased risk of fracture." Measuring bone strength, Biomechanical Computed Tomography analysis (BCT), namely, finite element analysis of a patient's clinical-resolution computed tomography (CT) scan, is now available in the USA as a Medicare screening benefit for osteoporosis diagnostic testing. Helping to address under-diagnosis of osteoporosis, BCT can be applied "opportunistically" to most existing CT scans that include the spine or hip regions and were previously obtained for an unrelated medical indication. For the BCT test, no modifications are required to standard clinical CT imaging protocols. The analysis provides measurements of bone strength as well as a dual-energy X-ray absorptiometry (DXA)-equivalent bone mineral density (BMD) T-score at the hip and a volumetric BMD of trabecular bone at the spine. Based on both the bone strength and BMD measurements, a physician can identify osteoporosis and assess fracture risk (high, increased, not increased), without needing confirmation by DXA. To help introduce BCT to clinicians and health care professionals, we describe in this review the currently available clinical implementation of the test (VirtuOst), its application for managing patients, and the underlying supporting evidence; we also discuss its main limitations and how its results can be interpreted clinically. Together, this body of evidence supports BCT as an accurate and convenient diagnostic test for osteoporosis in both sexes, particularly when used opportunistically for patients already with CT. Biomechanical Computed Tomography analysis (BCT) uses a patient's CT scan to measure both bone strength and bone mineral density at the hip or spine. Performing at least as well as DXA for both diagnosing osteoporosis and assessing fracture risk, BCT is particularly well-suited to "opportunistic" use for the patient without a recent DXA who is undergoing or has previously undergone CT testing (including hip or spine regions) for an unrelated medical condition.


Assuntos
Osteoporose , Tomografia Computadorizada por Raios X , Absorciometria de Fóton , Idoso , Densidade Óssea , Feminino , Humanos , Masculino , Medicare , Osteoporose/diagnóstico por imagem , Estados Unidos
4.
Dysphagia ; 34(6): 862-868, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30694413

RESUMO

While voice-related disorders in Parkinson's disease (PD) are commonly discussed in the literature, dysphagia in PD is less widely published. Vocal fold augmentation, including injection laryngoplasty (IL), is a well-established treatment for glottal insufficiency (Cates et al. in Otolaryngol Head Neck Surg 155(3):454-457, 2016). This study aimed to observe the effects of IL in PD patients with vocal bowing, with or without therapy, on glottic closure and patient-reported dysphagia outcomes. The study design was based on retrospectively collected database and cohort-case series. PD patients selected for retrospective review over a 2-year period were referred and evaluated in the Voice, Swallowing, and Airway multidisciplinary clinic by speech language pathologist and laryngologist, and were undergoing IL. Charts were reviewed for age, gender, Body Mass Index (BMI), onset of PD, and Movement Disorders Society-Unified Parkinson's Disease Rating Scale Part 3 (MDS-UPDRS) scoring. We compared pre/postoperatively (> 1 < 3 months) using validated patient-reported outcome tools: Reflux Symptom Index (RSI), Glottal Function Index (GFI), Eating Assessment Tool-10 (EAT), and stroboscopic examinations. The study included 14 patients undergoing 22 IL or 1.6 IL/patient: mean age 70 years (63-80), 100% male, and BMI 25.9 ± 4.3 (mean ± SD). MDS-UPDRS scoring 33 ± 20 (moderate severity), with time between PD diagnosis and IL 8 ± 10 years. All patients had pre- and post-stroboscopic examinations; however, only 4:14 underwent formal swallowing evaluation. Overall, 14 IL patients improved on patient-reported measures (ΔRSI = 4; ΔGFI = 3; ΔEAT = 4). Based on the findings of the study, we conclude that PD is a progressive neurodegenerative condition with dysphagia. The presented pilot data suggest that IL may be considered as a beneficial adjunct for PD patients with glottal insufficiency. LEVEL OF EVIDENCE: 4.


Assuntos
Transtornos de Deglutição/etiologia , Laringoplastia/métodos , Doença de Parkinson/complicações , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Distúrbios da Voz/etiologia , Distúrbios da Voz/cirurgia
5.
Osteoporos Int ; 28(11): 3283-3284, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28936598

RESUMO

We evaluated the prevalence of osteoporosis using the osteoporosis diagnostic criteria developed by the National Bone Health Alliance (NBHA), which includes qualified fractures, FRAX score in addition to BMD. The expanded definition increases the prevalence compared to BMD alone definitions; however, it may better identify those at elevated fracture risk. Recently an NBHA working Group published a paper in OI with recommendations for expanding the criteria that would constitute an osteoporosis diagnosis in postmenopausal women and in men over age 50 for use in the US - Siris et al., Osteoporosis International 25(%): 1439-1443, 2014. The recommendations have now been endorsed by NOF, ASBMR and a number of professional medical groups and appear in the NOF Clinician's Guide. The new diagnostic criteria continue to include a T-score by DXA of spine or hip that is less than or equal to -2.5, but alternatively also include a hip fracture with or without BMD testing or a vertebral, pelvis, proximal humerus and in some cases a distal forearm fracture in a person with low bone mass, or a FRAX score that meets or exceeds the NOF Guide osteoporosis treatment cut point.


Assuntos
Osteoporose/diagnóstico , Osteoporose/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/fisiopatologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/fisiopatologia , Prevalência , Medição de Risco/métodos , Estados Unidos/epidemiologia
6.
Osteoporos Int ; 28(4): 1225-1232, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27966104

RESUMO

We evaluated the prevalence of osteoporosis using the osteoporosis diagnostic criteria developed by the National Bone Health Alliance (NBHA), which includes qualified fractures, FRAX score in addition to bone mineral density (BMD). The expanded definition increases the prevalence compared to BMD alone definitions; however, it may better identify those at elevated fracture risk. PURPOSE: The purpose of this paper is to estimate the prevalence of osteoporosis in US adults ≥50 years using the NBHA osteoporosis diagnostic criteria. METHODS: Utilizing 2005-2008 data of the National Health and Nutrition Examination Survey (NHANES), we identified participants with osteoporosis with any one of the following: (1) femoral neck or lumbar spine T-score ≤ -2.5; (2) low trauma hip fracture irrespective of BMD or clinical vertebral, proximal humerus, pelvis, or distal forearm fracture with a T-score >-2.5 <-1.0; or (3) FRAX score at the National Osteoporosis Foundation intervention thresholds (≥3% for hip fracture or ≥20% for major osteoporotic fracture). We estimated the prevalence overall and by gender and age. RESULTS: Our sample included 1948 (54.3%) men and 1639 (45.7%) women. Approximately 12% were 80+ years and 21% were from racial/ethnic minority groups. We estimated that 16.0% (0.8) of men and 29.9% (1.0) of women 50+ years have osteoporosis. The prevalence increases with age to 46.3% in men and 77.1% in women 80+ years. The combination of FRAX score and fractures was the largest contributing factor defining osteoporosis in men (70-79, 88.1%; 80+, 80.1%), whereas T-score was the largest contributing factor in women (70-79, 49.2%; 80+, 43.5%). CONCLUSIONS: We found that 16% of men and 29.9% of women 50+ have osteoporosis based on the NBHA diagnostic criteria. Although the expanded definition increases the prevalence compared to BMD alone-based definitions, it may better identify those at elevated fracture risk in order to reduce the burden of fractures in older adults.


Assuntos
Osteoporose/diagnóstico , Osteoporose/epidemiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Feminino , Colo do Fêmur/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoporose/fisiopatologia , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/epidemiologia , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/fisiopatologia , Fraturas por Osteoporose/prevenção & controle , Prevalência , Medição de Risco/métodos , Distribuição por Sexo , Estados Unidos/epidemiologia
7.
Osteoporos Int ; 28(7): 2115-2128, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28391447

RESUMO

We investigated the sensitivity of distal bone density, structure, and strength measurements by high-resolution peripheral quantitative computed tomography (HR-pQCT) to variability in limb length. Our results demonstrate that HR-pQCT should be performed at a standard %-of-total-limb-length to avoid substantial measurement bias in population study comparisons and the evaluation of individual skeletal status in a clinical context. INTRODUCTION: High-resolution peripheral quantitative computed tomography (HR-pQCT) measures of bone do not account for anatomic variability in bone length: a 1-cm volume is acquired at a fixed offset from an anatomic landmark. Our goal was to evaluate HR-pQCT measurement variability introduced by imaging fixed vs. proportional volumes and to propose a standard protocol for relative anatomic positioning. METHODS: Double-length (2-cm) scans were acquired in 30 adults. We compared measurements from 1-cm sub-volumes located at the default fixed offset, and the average %-of-length offset. The average position corresponded to 4.0% ± 1.1 mm for radius, and 7.2% ± 2.2 mm for tibia. We calculated the RMS difference in bone parameters and T-scores to determine the measurement variability related to differences in limb length. We used anthropometric ratios to estimate the mean limb length for published HR-pQCT reference data, and then calculated mean %-of-length offsets. RESULTS: Variability between fixed vs. relative scan positions was highest in the radius, and for cortical bone in general (RMS difference Ct.Th = 19.5%), while individuals had T-score differentials as high as +3.0 SD (radius Ct.BMD). We estimated that average scan position for published HR-pQCT reference data corresponded to 4.0% at the radius, and 7.3% at tibia. CONCLUSION: Variability in limb length introduces significant bias to HR-pQCT measures, confounding cross-sectional analyses and limiting the clinical application for individual assessment of skeletal status. We propose to standardize scan positioning using 4.0 and 7.3% of total bone length for the distal radius and tibia, respectively.


Assuntos
Densidade Óssea/fisiologia , Rádio (Anatomia)/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos , Antropometria/métodos , Feminino , Análise de Elementos Finitos , Antebraço/anatomia & histologia , Humanos , Perna (Membro)/anatomia & histologia , Masculino , Rádio (Anatomia)/fisiologia , Reprodutibilidade dos Testes , Tíbia/fisiologia , Tomografia Computadorizada por Raios X/normas
8.
Osteoporos Int ; 28(1): 245-257, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27475931

RESUMO

In this study, we determined that operator positioning precision contributes significant measurement error in high-resolution peripheral quantitative computed tomography (HR-pQCT). Moreover, we developed software to quantify intra- and inter-operator variability and demonstrated that standard positioning training (now available as a web-based application) can significantly reduce inter-operator variability. INTRODUCTION: HR-pQCT is increasingly used to assess bone quality, fracture risk, and anti-fracture interventions. The contribution of the operator has not been adequately accounted in measurement precision. Operators acquire a 2D projection ("scout view image") and define the region to be scanned by positioning a "reference line" on a standard anatomical landmark. In this study, we (i) evaluated the contribution of positioning variability to in vivo measurement precision, (ii) measured intra- and inter-operator positioning variability, and (iii) tested if custom training software led to superior reproducibility in new operators compared to experienced operators. METHODS: To evaluate the operator in vivo measurement precision, we compared precision errors calculated in 64 co-registered and non-co-registered scan-rescan images. To quantify operator variability, we developed software that simulates the positioning process of the scanner's software. Eight experienced operators positioned reference lines on scout view images designed to test intra- and inter-operator reproducibility. Finally, we developed modules for training and evaluation of reference line positioning. We enrolled six new operators to participate in a common training, followed by the same reproducibility experiments performed by the experienced group. RESULTS: In vivo precision errors were up to threefold greater (Tt.BMD and Ct.Th) when variability in scan positioning was included. The inter-operator precision errors were significantly greater than the short-term intra-operator precision (p < 0.001). New trained operators achieved comparable intra-operator reproducibility to experienced operators and lower inter-operator reproducibility (p < 0.001). Precision errors were significantly greater for the radius than for the tibia. CONCLUSION: Operator reference line positioning contributes significantly to in vivo measurement precision and is significantly greater for multi-operator datasets. Inter-operator variability can be significantly reduced using a systematic training platform, now available online ( http://webapps.radiology.ucsf.edu/refline/ ).


Assuntos
Competência Clínica , Osteoporose/diagnóstico por imagem , Tomografia Computadorizada por Raios X/normas , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos , Feminino , Humanos , Capacitação em Serviço/métodos , Masculino , Rádio (Anatomia)/diagnóstico por imagem , Reprodutibilidade dos Testes , Design de Software , Tíbia/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
9.
Osteoporos Int ; 26(5): 1655-60, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25572049

RESUMO

UNLABELLED: Substantial variability exists in the serum 25(OH)D increase observed in response to vitamin D supplementation. Measurement of circulating cholecalciferol and 24,25(OH)2D, as indicators of vitamin D absorption and degradation, respectively, account for approximately half of the variation in serum 25(OH)D observed following supplementation. INTRODUCTION: Vitamin D supplementation produces a variable response in serum 25(OH)D. This variability likely reflects, in part, differences in vitamin D absorption and/or degradation. Despite this variation in response, virtually all expert recommendations endorse a fixed vitamin D supplementation dose, an approach also used in most prospective studies. Such utilization of a single vitamin D dose does not assure attaining any pre-specified target 25(OH)D level, thereby compromising clinical care and prospective supplementation trials. This study begins addressing this weakness by exploring the feasibility of vitamin D metabolite measurements to predict serum 25(OH)D level attained following supplementation. METHODS: Ninety-one community-dwelling postmenopausal women with baseline 25(OH)D of 10-30 ng/mL received oral vitamin D3, 2300 or 2500 IU, daily for 4-6 months. Serum 25(OH)D, cholecalciferol (D3), and 24,25(OH)2D were measured before and at the end of supplementation to determine if metabolite concentrations allow prediction of the 25(OH)D level attained. RESULTS: From baseline and follow-up data, we derived a multiple linear regression model predicting posttreatment 25(OH)D as follows: final 25(OH)D = 8.3 + (1.05*initial 25(OH)D) - (7.7*initial 24,25(OH)2D) + (0.53*final D3) + (4.2*final 24,25(OH)2D). This model has an adjusted R(2) = 0.55, thus accounting for approximately half of the observed variance in the final 25(OH)D level. CONCLUSIONS: The contributions of circulating cholecalciferol and 24,25(OH)2D to this predictive model can be considered as indicators of intestinal absorption and clearance, respectively. This paradigm requires further study; it may allow efficient "treat-to-25(OH)D-target" strategies useful in optimizing prospective studies and clinical practice.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Colecalciferol/uso terapêutico , Suplementos Nutricionais , Osteoporose Pós-Menopausa/tratamento farmacológico , 24,25-Di-Hidroxivitamina D 3/sangue , Idoso , Monitoramento de Medicamentos/métodos , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Vitamina D/análogos & derivados , Vitamina D/sangue
10.
Br J Surg ; 101(11): 1350-7; discussion 1357, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25131598

RESUMO

BACKGROUND: Abdominal aortic aneurysm (AAA) is an important cause of sudden death; however, there are currently incomplete means to predict the risk of AAA rupture. AAA peak wall stress (PWS) can be estimated using finite element analysis (FEA) methods from computed tomography (CT) scans. The question is whether AAA PWS can predict AAA rupture. The aim of this systematic review was to compare PWS in patients with ruptured and intact AAA. METHODS: The MEDLINE database was searched on 25 May 2013. Case-control studies assessing PWS in asymptomatic intact, and acutely symptomatic or ruptured AAA from CT scans using FEA were included. Data were extracted independently. A random-effects model was used to calculate standard mean differences (SMDs) for PWS measurements. RESULTS: Nine studies assessing 348 individuals were identified and used in the meta-analysis. Results from 204 asymptomatic intact and 144 symptomatic or ruptured AAAs showed that PWS was significantly greater in the symptomatic/ ruptured AAAs compared with the asymptomatic intact AAAs (SMD 0·95, 95 per cent confidence interval 0·71 to 1·18; P < 0·001). The findings remained significant after adjustment for mean systolic blood pressure, standardized at 120 mmHg (SMD 0·68, 0·39 to 0·96; P < 0·001). Minimal heterogeneity between studies was noted (I(2) = 0 per cent). CONCLUSION: This study suggests that PWS is greater in symptomatic or ruptured AAA than in asymptomatic intact AAA.


Assuntos
Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/fisiopatologia , Ruptura Aórtica/fisiopatologia , Pressão Sanguínea/fisiologia , Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/patologia , Ruptura Aórtica/patologia , Humanos , Fatores de Risco , Tamanho da Amostra , Estresse Fisiológico/fisiologia
11.
Osteoporos Int ; 25(3): 887-95, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24114401

RESUMO

SUMMARY: We isolate and characterize osteoblasts from humans without in vitro culture. These techniques should be broadly applicable to studying the pathogenesis of osteoporosis and other bone disorders. INTRODUCTION: There is currently no data regarding the expression of specific genes or pathways in human osteoblasts that have not been subjected to extensive in vitro culture. Thus, we developed methods to rapidly isolate progressively enriched osteoblast populations from humans and characterized these cells. METHODS: Needle bone biopsies of the posterior iliac crest were subjected to sequential collagenase digests. The cells from the second digest were stained with an alkaline phosphatase (AP) antibody, and the AP+ cells were isolated using magnetic cell sorting. RESULTS: Relative to AP- cells, the AP+ cells contained virtually all of the mineralizing cells and were enriched for key osteoblast marker genes. The AP+ cells were further purified by depletion of cells expressing CD45, CD34, or CD31 (AP+/CD45/34/31- cells), which represented a highly enriched human osteoblast population devoid of hematopoietic/endothelial cells. These cells expressed osteoblast marker genes but very low to undetectable levels of SOST. We next used high-throughput RNA sequencing to compare the transcriptome of the AP+/CD45/34/31- cells to human fibroblasts and identified genes and pathways expressed only in human osteoblasts in vivo, but not in fibroblasts, including 448 genes unique to human osteoblasts. CONCLUSIONS: We provide a detailed characterization of highly enriched human osteoblast populations without in vitro culture. These techniques should be broadly applicable to studying the pathogenesis of osteoporosis and other bone disorders.


Assuntos
Osteoblastos/patologia , Osteoporose/patologia , Adulto , Idoso , Fosfatase Alcalina/metabolismo , Biópsia por Agulha/métodos , Separação Celular/métodos , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Ílio/patologia , Masculino , Pessoa de Meia-Idade , Osteoblastos/metabolismo , Osteoporose/genética , Osteoporose/metabolismo , Microtomografia por Raio-X/métodos , Adulto Jovem
12.
Osteoporos Int ; 25(5): 1439-43, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24577348

RESUMO

UNLABELLED: Osteoporosis causes an elevated fracture risk. We propose the continued use of T-scores as one means for diagnosis but recommend that, alternatively, hip fracture; osteopenia-associated vertebral, proximal humerus, pelvis, or some wrist fractures; or FRAX scores with ≥3% (hip) or 20% (major) 10-year fracture risk also confer an osteoporosis diagnosis. INTRODUCTION: Osteoporosis is a common disorder of reduced bone strength that predisposes to an increased risk for fractures in older individuals. In the USA, the standard criterion for the diagnosis of osteoporosis in postmenopausal women and older men is a T-score of ≤ -2.5 at the lumbar spine, femur neck, or total hip by bone mineral density testing. METHODS: Under the direction of the National Bone Health Alliance, 17 clinicians and clinical scientists were appointed to a working group charged to determine the appropriate expansion of the criteria by which osteoporosis can be diagnosed. RESULTS: The group recommends that postmenopausal women and men aged 50 years should be diagnosed with osteoporosis if they have a demonstrable elevated risk for future fractures. This includes having a T-score of less than or equal to -2.5 at the spine or hip as one method for diagnosis but also permits a diagnosis for individuals in this population who have experienced a hip fracture with or without bone mineral density (BMD) testing and for those who have osteopenia by BMD who sustain a vertebral, proximal humeral, pelvic, or, in some cases, distal forearm fracture. Finally, the term osteoporosis should be used to diagnose individuals with an elevated fracture risk based on the World Health Organization Fracture Risk Algorithm, FRAX. CONCLUSIONS: As new ICD-10 codes become available, it is our hope that this new understanding of what osteoporosis represents will allow for an appropriate diagnosis when older individuals are recognized as being at an elevated risk for fracture.


Assuntos
Osteoporose/diagnóstico , Absorciometria de Fóton/métodos , Fatores Etários , Idoso , Algoritmos , Densidade Óssea/fisiologia , Feminino , Colo do Fêmur/fisiopatologia , Articulação do Quadril/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoporose/fisiopatologia , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/fisiopatologia , Medição de Risco/métodos
13.
Osteoporos Int ; 23(3): 1123-30, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21617991

RESUMO

UNLABELLED: Serum sclerostin levels are associated with cortical porosity, suggesting that changes in sclerostin production during growth may play a role in defining cortical structure. INTRODUCTION: Sclerostin, produced by osteocytes, is a potent inhibitor of Wnt signaling and bone formation. While sclerostin levels increase with age in adults and are higher in men compared to women, there is currently no information on changes in circulating sclerostin levels during growth in humans. METHODS: We measured serum sclerostin levels in 6- to 21-year-old girls (n = 62) and boys (n = 56) and related these to trabecular and cortical bone microarchitectural parameters using high-resolution peripheral quantitative computed tomography and to markers of bone turnover. RESULTS: Serum sclerostin levels were higher in boys as compared to girls and declined in both sexes following the onset of puberty. There was no consistent relationship between sclerostin levels and trabecular bone parameters in either sex. However, serum sclerostin levels were inversely associated with cortical volumetric bone mineral density and cortical thickness in girls and positively associated with the cortical porosity index in both girls and boys. Bone turnover markers were positively correlated with serum sclerostin levels in both sexes. CONCLUSION: The gender difference in serum sclerostin levels appears to be established during puberty, and sclerostin levels tend to decline in late puberty in both girls and boys. Serum sclerostin levels are associated with cortical porosity, suggesting that changes in sclerostin production during growth may play a role in defining cortical structure.


Assuntos
Envelhecimento/sangue , Desenvolvimento Ósseo/fisiologia , Proteínas Morfogenéticas Ósseas/sangue , Proteínas Adaptadoras de Transdução de Sinal , Adolescente , Determinação da Idade pelo Esqueleto , Envelhecimento/fisiologia , Biomarcadores/sangue , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Criança , Feminino , Marcadores Genéticos , Crescimento e Desenvolvimento/fisiologia , Humanos , Masculino , Porosidade , Puberdade/fisiologia , Caracteres Sexuais , Tomografia Computadorizada por Raios X , Adulto Jovem
14.
Osteoporos Int ; 23(1): 155-62, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22057550

RESUMO

UNLABELLED: Using combined dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography, we demonstrate that men matched with women for femoral neck (FN) areal bone mineral density (aBMD) have lower volumetric BMD (vBMD), higher bone cross-sectional area, and relatively similar values for finite element (FE)-derived bone strength. INTRODUCTION: aBMD by DXA is widely used to identify patients at risk for osteoporotic fractures. aBMD is influenced by bone size (i.e., matched for vBMD, larger bones have higher aBMD), and increasing evidence indicates that absolute aBMD predicts a similar risk of fracture in men and women. Thus, we sought to define the relationships between FN aBMD (assessed by DXA) and vBMD, bone size, and FE-derived femoral strength obtained from quantitative computed tomography scans in men versus women. METHODS: We studied men and women aged 40 to 90 years and not on osteoporosis medications. RESULTS: In 114 men and 114 women matched for FN aBMD, FN total cross-sectional area was 38% higher (P < 0.0001) and vBMD was 16% lower (P < 0.0001) in the men. FE models constructed in a subset of 28 women and 28 men matched for FN aBMD showed relatively similar values for bone strength and the load-to-strength ratio in the two groups. CONCLUSIONS: In this cohort of young and old men and women from Rochester, MN, USA who are matched by FN aBMD, because of the offsetting effects of bone size and vBMD, femoral strength and the load-to-strength ratio tended to be relatively similar across the sexes.


Assuntos
Densidade Óssea/fisiologia , Colo do Fêmur/fisiologia , Absorciometria de Fóton , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Envelhecimento/fisiologia , Antropometria/métodos , Feminino , Colo do Fêmur/anatomia & histologia , Colo do Fêmur/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/patologia , Fraturas por Osteoporose/fisiopatologia , Caracteres Sexuais , Tomografia Computadorizada por Raios X/métodos , Suporte de Carga
15.
J Laryngol Otol ; 136(12): 1249-1253, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35081997

RESUMO

BACKGROUND: There is currently limited evidence regarding the potential complications of sphenopalatine artery ligation. The post-operative outcomes at two secondary care centres over a 10-year period were reviewed. METHODS: A retrospective review was undertaken of patients undergoing emergency and elective sphenopalatine artery ligation between January 2011 and January 2021. Their demographics, peri-operative care and post-operative outcomes were recorded. The median follow-up time was 54 days (range, 0-2657 days). RESULTS: Ninety-one patients were included. Four patients (4.4 per cent) had a septal perforation at post-operative review. Nineteen patients (20.9 per cent) had post-operative bleeding that extended their in-patient stay, with five patients (5.5 per cent) requiring revision surgery. Pre-operative non-dissolvable nasal packing was used a median of 1 time (range, 0-8 times). CONCLUSION: Further research on outcomes of sphenopalatine artery ligation is needed. Pre-operative non-dissolvable nasal packing, concurrent septal surgical procedures, surgical techniques, and co-morbidities such as hypertension represent potential confounding factors that could not be further assessed in this small, retrospective study.


Assuntos
Artérias , Ligadura , Humanos , Artérias/cirurgia , Epistaxe/epidemiologia , Epistaxe/prevenção & controle , Ligadura/efeitos adversos , Estudos Retrospectivos , Centros de Cuidados de Saúde Secundários , Resultado do Tratamento , Complicações Pós-Operatórias/epidemiologia
16.
Osteoporos Int ; 22(12): 3047-54, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21308363

RESUMO

UNLABELLED: Bone strength at the ultradistal radius, quantified by micro-finite element modeling, can be predicted by variables obtained from high-resolution peripheral quantitative computed tomography scans. The specific formula for this bone strength surrogate (-555.2 + 8.1 × [trabecular vBMD] + 19.6 × [cortical area] + 4.2 × [total cross-sectional area]) should be validated and tested in fracture risk assessment. INTRODUCTION: The purpose of this study was to identify key determinants of ultradistal radius (UDR) strength and evaluate their relationships with age, sex steroid levels, and measures of habitual skeletal loading. METHODS: UDR failure load (~strength) was assessed by micro-finite element (µFE) modeling in 105 postmenopausal controls from an earlier forearm fracture case-control study. Predictors of bone strength obtained by high-resolution peripheral quantitative computed tomography (HRpQCT) in this group were then evaluated in a population-based cohort of 214 postmenopausal women. Sex steroids were measured by mass spectrometry. RESULTS: A surrogate variable (-555.2 + 8.1 × [trabecular vBMD] + 19.6 × [cortical area] + 4.2 × [total cross-sectional area]) predicted UDR strength modeled by µFE (R(2) = 0.81), and all parameters except total cross-sectional area declined with age. Evaluated cross-sectionally, the 21% fall in predicted bone strength between ages 40-49 years and 80+ years more resembled the change in trabecular volumetric bone mineral density (vBMD) (-15%) than that in cortical area (-41%). In multivariable analyses, measures of body composition and physical activity were stronger predictors of UDR trabecular vBMD, cortical area, total cross-sectional area, and predicted bone strength than were sex steroid levels, but bio-available estradiol and testosterone were correlated with body mass. CONCLUSIONS: Bone strength at the UDR, as quantified by µFE, can be predicted from variables obtained by HRpQCT. Predicted bone strength declines with age with changes in UDR trabecular vBMD and cortical area, related in turn to reduced skeletal loading and sex steroid levels. The predicted bone strength formula should be validated and tested in fracture risk assessment.


Assuntos
Antebraço/anatomia & histologia , Modelos Biológicos , Rádio (Anatomia)/anatomia & histologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Estudos de Casos e Controles , Feminino , Análise de Elementos Finitos , Antebraço/diagnóstico por imagem , Hormônios Esteroides Gonadais/análise , Humanos , Espectrometria de Massas , Pessoa de Meia-Idade , Pós-Menopausa , Rádio (Anatomia)/diagnóstico por imagem , Fatores de Risco , Fatores Sexuais , Tomografia Computadorizada por Raios X/métodos
17.
Osteoporos Int ; 22(11): 2789-98, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21509585

RESUMO

UNLABELLED: The consensus views on osteoporosis in men are reported. INTRODUCTION: A workshop was convened within a meeting on osteoporosis in men to identify areas of consensus amongst the panel (the authors) and the participants of the meeting. METHODS: A public debate with an expert panel on preselected topics was conducted. RESULTS AND CONCLUSIONS: Consensus views were reached on diagnostic criteria and several aspects on the pathophysiology and treatment of osteoporosis in men.


Assuntos
Densidade Óssea/fisiologia , Osteoporose , Absorciometria de Fóton , Acidentes por Quedas/estatística & dados numéricos , Androgênios/uso terapêutico , Índice de Massa Corporal , Feminino , Colo do Fêmur/diagnóstico por imagem , Humanos , Masculino , Osteoporose/diagnóstico , Osteoporose/epidemiologia , Osteoporose/terapia , Fraturas por Osteoporose/epidemiologia , Padrões de Referência , Fatores de Risco , Fatores Sexuais , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue , Testosterona/uso terapêutico
18.
Osteoporos Int ; 22(5): 1627-31, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20658128

RESUMO

SUMMARY: Compared to white women, lower areal bone mineral density (aBMD) in middle-aged Vietnamese immigrants is due to reduced trabecular volumetric bone mineral density (vBMD), which in turn is associated with greater trabecular separation along with lower estrogen levels. INTRODUCTION: The epidemiology of osteoporosis in Asian populations is still poorly known, but we previously found a deficit in lumbar spine aBMD among postmenopausal Southeast Asian women, compared to white women, that persisted after correction for bone size. This issue was revisited using more sophisticated imaging techniques. METHODS: Twenty Vietnamese immigrants (age, 44-79 years) were compared to 162 same-aged white women with respect to aBMD at the hip, spine and wrist, vBMD at the hip and spine by quantitative computed tomography and vBMD and bone microstructure at the ultradistal radius by high-resolution pQCT. Bone turnover and sex steroid levels were assessed in a subset (20 Vietnamese and 40 white women). RESULTS: The aBMD was lower at all sites among the Vietnamese women, but femoral neck vBMD did not differ from middle-aged white women. Significant differences in lumbar spine and ultradistal radius vBMD in the Vietnamese immigrants were due to lower trabecular vBMD, which was associated with increased trabecular separation. Bone resorption was elevated and bone formation depressed among the Vietnamese immigrants, although trends were not statistically significant. Serum estradiol was positively associated with trabecular vBMD in the Vietnamese women, but their estrogen levels were dramatically lower compared to white women. CONCLUSIONS: Although reported discrepancies in aBMD among Asian women are mainly an artifact of smaller bone size, we identified a specific deficit in the trabecular bone among a sample of Vietnamese immigrants that may be related to low estrogen levels and which needs further study.


Assuntos
Povo Asiático/estatística & dados numéricos , Densidade Óssea/fisiologia , Adulto , Idoso , Biomarcadores/sangue , Remodelação Óssea/fisiologia , Reabsorção Óssea/sangue , Reabsorção Óssea/etnologia , Reabsorção Óssea/fisiopatologia , Emigrantes e Imigrantes , Estradiol/sangue , Feminino , Colo do Fêmur/fisiologia , Humanos , Vértebras Lombares/fisiologia , Pessoa de Meia-Idade , Minnesota/epidemiologia , Peptídeo Natriurético Tipo C/sangue , Rádio (Anatomia)/fisiologia , Tomografia Computadorizada por Raios X/métodos
19.
Clin Nutr ; 40(4): 2435-2442, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33176926

RESUMO

BACKGROUND & AIMS: Accurate and reproducible biomarkers are required to allow a more personalized approach to patient care. Body composition is one such biomarker affecting outcomes in a range of surgical and oncological conditions. The aim of this study is to determine the age and sex specific distribution of body composition data, based on information gathered from computed tomography (CT). METHODS: This prospective study used healthy subjects from the medical records linkage of the Rochester Epidemiology Project, based in Minnesota, USA. Each patient had a CT scan without intravenous contrast performed between 1999 and 2001. Quantification was performed using previously validated semi-automated in-house developed software for body composition analysis. Subcutaneous adipose tissue area, visceral adipose tissue area, intermuscular adipose tissue area and skeletal muscle area were measured and indexed to subject height. Generalized Additive Models for Location, Scale and Shape were used to assess the location, scale, and shape of each variable across age, stratified by sex. Z-scores specific to sex were assessed for each of the parameters analyzed. Age-specific z-scores were calculated using the formula: Z = (Index Variable - µ)/σ or Z = (√ (Index Variable) - µ)/σ. RESULTS: There were 692 subjects enrolled in the study. The fitted model equation was offered for each variable with values presented for µ and σ. Modelling with penalized splines was performed for VAT index, IMAT index and total adipose tissue index. Scatterplots of each variable were produced with lines of Z-scores as a visual representation. CONCLUSION: This study offers comparative data to allow comparison amongst multiple populations. This will form an important reference for future research and clinical practice.


Assuntos
Tecido Adiposo/anatomia & histologia , Composição Corporal , Adulto , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Feminino , Humanos , Gordura Intra-Abdominal/anatomia & histologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/anatomia & histologia , Estudos Prospectivos , Valores de Referência , Gordura Subcutânea/anatomia & histologia , Tomografia Computadorizada por Raios X
20.
BJS Open ; 5(2)2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33839750

RESUMO

BACKGROUND: There is an unmet need for suitable ex vivo large animal models in experimental gastroenterology and intestinal transplantation. This study details a reliable and effective technique for ex vivo normothermic perfusion (EVNP) of segmental porcine small intestine. METHODS: Segments of small intestine, 1.5-3.0 m in length, were retrieved from terminally anaesthetized pigs. After a period of cold ischaemia, EVNP was performed for 2 h at 37°C with a mean pressure of 80 mmHg using oxygenated autologous blood diluted with Ringer's solution. The duration of EVNP was extended to 4 h for a second set of experiments in which two segments of proximal to mid-ileum (1.5-3.0 m) were retrieved from each animal and reperfused with whole blood (control) or leucocyte-depleted blood to examine the impact of leucocyte depletion on reperfusion injury. RESULTS: After a mean cold ischaemia time of 5 h and 20 min, EVNP was performed in an initial group of four pigs. In the second set of experiments, five pigs were used in each group. In all experiments bowel segments were well perfused and exhibited peristalsis during EVNP. Venous glucose levels significantly increased following luminal glucose stimulation (mean(s.e.m.) basal level 1.8(0.6) mmol/l versus peak 15.5(5.8) mmol/l; P < 0.001) and glucagon-like peptide 1 (GLP-1) levels increased in all experiments, demonstrating intact absorptive and secretory intestinal functions. There were no significant differences between control and leucocyte-depleted animals regarding blood flow, venous glucose, GLP-1 levels or histopathology at the end of 4 h of EVNP. CONCLUSIONS: This novel model is suitable for the investigation of gastrointestinal physiology, pathology and ischaemia reperfusion injury, along with evaluation of potential therapeutic interventions.


Assuntos
Intestino Delgado/irrigação sanguínea , Intestino Delgado/transplante , Preservação de Órgãos/métodos , Perfusão/métodos , Animais , Intestino Delgado/patologia , Pós-Condicionamento Isquêmico , Precondicionamento Isquêmico , Masculino , Suínos
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