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1.
J Endocrinol Invest ; 45(5): 1039-1044, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35079976

RESUMO

OBJECTIVE: Although calcitriol is essential for bone healing, its serum concentrations are low after hip surgery, and they continue to decline during bone healing. This study aimed to test the hypothesis of an association of changes in calcitriol production with the status of fibroblast growth factor 23 (FGF23) and iron deficiency after elective hip replacement for coxarthrosis. METHODS: In this prospective study, we measured the biomarkers of 17 patients undergoing elective hip replacement on admission, on the first day after surgery, and at the regular check-up after 48 ± 8 days. The serum concentrations of 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, transferrin, ferritin, parathyroid hormone, intact plasma FGF23 (iFGF23) and C-terminal FGF23 (cFGF23) were determined. RESULTS: In our patients who underwent elective hip replacement, significant correlations existed between the percent change in the conversion rate of 25(OH)D to 1,25(OH)2D, plasma intact to C-terminal FGF23 ratio, and serum iron. CONCLUSIONS: The production of calcitriol is compromised after elective hip replacement surgery, leading to reduced levels of active vitamin D in the serum. Significant correlations between the percent change in the conversion rate of 25(OH)D to 1,25(OH)2D, plasma intact to C-terminal FGF23 ratio, and serum iron on the first day as well as 7 weeks after surgery could inspire future studies to determine whether and how calcitriol deficiency should be corrected, especially in fracture cases.


Assuntos
Calcitriol , Fatores de Crescimento de Fibroblastos , Humanos , Ferro , Hormônio Paratireóideo , Estudos Prospectivos , Vitamina D
2.
J Endocrinol Invest ; 44(9): 1847-1855, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33492601

RESUMO

OBJECTIVE: To assess the decrease in serum calcitriol concentrations after hip fracture. METHODS: Serum concentrations of calcitriol, 25(OH)D, parathyroid hormone (PTH), directly measured free 25(OH)D, and indices of bone formation were measured in elderly patients with hip fracture (HF) and patients with elective hip replacement (EHR) at admission and after 7 weeks. RESULTS: A total of 45 patients with HF and 17 patients with EHR completed this prospective study. Baseline serum calcitriol levels were ≤ 60 pmol/l in 26% of the HF patients. After 7 weeks, they significantly decreased (p < 0.001). In patients with EHR, serum calcitriol was within the reference range in all but one patient and did not change during the 7-week recovery phase. Seven weeks after HF, a significant positive relationship was observed between the change in calcitriol and serum 25(OH)D concentration (r = 0.385, p = 0.009) and free 25(OH)D (r = 0.296, p = 0.048), and a decrease in calcitriol during recovery was associated with a decrease in serum PTH (p = 0.038). Seven weeks after HF, changes in both serum PTH and serum 25(OH)D concentrations contributed to the prediction of changes in serum calcitriol (R2 = 0.190, p = 0.012). CONCLUSIONS: Unlike patients with EHR, subjects with HF had low serum 25(OH)D and low free 25(OH)D concentrations at admission, while their serum 1,25D levels were relatively elevated. Decreases in circulating calcitriol levels in the 7 weeks following hip surgery were associated with a resolution of secondary hyperparathyroidism and low availability of free 25(OH)D.


Assuntos
Calcitriol/sangue , Consolidação da Fratura/fisiologia , Fraturas do Quadril/sangue , Vitamina D/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril , Feminino , Humanos , Masculino , Osteogênese , Hormônio Paratireóideo/sangue , Estudos Prospectivos , Valores de Referência , Vitamina D/sangue
3.
Osteoporos Int ; 31(10): 1935-1942, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32474650

RESUMO

FRAX® calculates the 10-year probability of major osteoporotic fractures (MOF), which are considered to have a greater clinical impact than other fractures. Our results suggest that, in postmenopausal women with severe osteoporosis, those treated with teriparatide had a 60% lower risk of FRAX®-defined MOF compared with those treated with risedronate. INTRODUCTION: The VERO trial was an active-controlled fracture endpoint clinical trial that enrolled postmenopausal women with severe osteoporosis. After 24 months, a 52% reduction in the hazard ratio (HR) of clinical fractures was reported in patients randomized to teriparatide compared with risedronate. We examined fracture results restricted to FRAX®-defined major osteoporotic fractures (MOF), which include clinical vertebral, hip, humerus, and forearm fractures. METHODS: In total, 1360 postmenopausal women (mean age 72.1 years) were randomized to receive subcutaneous daily teriparatide (20 µg) or oral weekly risedronate (35 mg). Patient cumulative incidence of ≥ 1 FRAX®-defined MOF and of all clinical fractures were estimated by Kaplan-Meier analyses, and the comparison between treatments was based on the stratified log-rank test. Additionally, an extended Cox model was used to estimate HRs at different time points. Incidence fracture rates were estimated at each 6-month interval. RESULTS: After 24 months, 16 (2.6%) patients in the teriparatide group had ≥ 1 low trauma FRAX®-defined MOF compared with 40 patients (6.4%) in the risedronate group (HR 0.40; 95% CI 0.23-0.68; p = 0.001). Clinical vertebral and radius fractures were the most frequent FRAX®-defined MOF sites. The largest difference in incidence rates of both FRAX®-defined MOF and all clinical fractures between treatments occurred during the 6- to 12-month period. There was a statistically significant reduction in fractures between groups as early as 7 months for both categories of clinical fractures analyzed. CONCLUSION: In postmenopausal women with severe osteoporosis, treatment with teriparatide was more efficacious than risedronate, with a 60% lower risk of FRAX®-defined MOF during the 24-month treatment period. Fracture risk was statistically significantly reduced at 7 months of treatment. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov Identifier: NCT01709110 EudraCT Number: 2012-000123-41.


Assuntos
Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Fraturas por Osteoporose , Idoso , Densidade Óssea , Conservadores da Densidade Óssea/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/prevenção & controle , Ácido Risedrônico/uso terapêutico , Teriparatida/uso terapêutico
4.
Bone ; 95: 41-46, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27826025

RESUMO

Prospective, controlled clinical trials in postmenopausal osteoporosis typically compare effects of an active drug with placebo in addition to vitamin D and calcium supplementation in both treatment arms. While clinical benefits are documented, the effect of this supplementation in the placebo arm and in clinical practice on bone material composition properties is unknown. The purpose of the present study was to evaluate these bone quality indices (specifically mineral/matrix, nanoporosity, glycosaminoglycan content, mineral maturity/crystallinity, and pyridinoline content) in patients that either received long-term vitamin D (400-1200IU) and calcium (1.0-1.5g) supplementation, or did not. We have analyzed by Raman microspectroscopy the bone forming trabecular surfaces of iliac crest in pre-treatment samples of a teriparatide study and the endpoint biopsies of the control arm obtained from the HORIZON trial. In general, the mineral/matrix ratio and the glycosaminoglycan (GAG) content was higher while nanoporosity, (a surrogate for tissue water content), the mineral maturity/crystallinity (MMC) and the pyridinoline (Pyd) content was lower in patients without long-term supplementation. Moreover, all indices were significantly dependent on tissue age. In conclusion, vitamin D and calcium supplementation is associated with altered mineral and organic matrix properties.


Assuntos
Matriz Óssea/metabolismo , Calcificação Fisiológica/efeitos dos fármacos , Cálcio/uso terapêutico , Suplementos Nutricionais , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/fisiopatologia , Vitamina D/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Aminoácidos/metabolismo , Análise de Variância , Matriz Óssea/efeitos dos fármacos , Cálcio/farmacologia , Feminino , Glicosaminoglicanos/metabolismo , Humanos , Nanopartículas/química , Porosidade , Análise Espectral Raman , Vitamina D/farmacologia
5.
Osteoporos Int ; 27(8): 2395-410, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26902094

RESUMO

Teriparatide (TPTD) is the only currently available therapeutic agent that increases the formation of new bone tissue and can provide some remediation of the architectural defects in the osteoporotic skeleton. The use of teriparatide clinically is limited to 24 months. We review clinical findings during daily teriparatide treatment over time. Teriparatide appears to increase bone formation more than bone resorption as determined biochemically and histologically. Teriparatide exerts its positive effects on bone formation in two distinct fashions. The first is direct stimulation of bone formation that occurs within active remodeling sites (remodeling-based bone formation) and on surfaces of bone previously inactive (modeling-based bone formation). The second is an increase in the initiation of new remodeling sites. Both processes contribute to the final increase in bone density observed by non-invasive tools such as DXA. Remodeling is the repair process by which skeletal tissue is maintained in a young healthy state, and when stimulated by TPTD is associated with a positive bone balance within each remodeling cavity. It seems likely therefore that this component will contribute to the anti-fracture efficacy of TPTD. Teriparatide reduces the risk of fracture, and this effect appears to increase with longer duration of therapy. The use of novel treatment regimens, including shorter courses, should be held in abeyance until controlled clinical trials are completed to define the relative fracture benefits of such approaches in comparison to the 24-month daily use of the agent. Summary In patients with osteoporosis at high risk for fracture, the full continuous 24-month course with teriparatide results in improved skeletal health and outcomes than shorter time periods.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osteoporose/tratamento farmacológico , Teriparatida/uso terapêutico , Densidade Óssea , Osso e Ossos/efeitos dos fármacos , Humanos
6.
Osteoporos Int ; 25(12): 2709-19, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25037600

RESUMO

UNLABELLED: The results of the present study, involving analysis of biopsies from patients who received teriparatide for 2 years and were previously either treatment-naïve or on long-term alendronate therapy, suggest that prior alendronate use does not blunt the favorable effects of teriparatide on bone quality. INTRODUCTION: Examine the effect of 2 years of teriparatide (TPTD) treatment on mineral and organic matrix properties of the newest formed bone in patients who were previously treatment-naïve (TN) or on long-term alendronate (ALN) therapy. METHODS: Raman and Fourier transform infrared microspectroscopic analyses were used to determine the mineral/matrix (M/M) ratio, the relative proteoglycan (PG) content, and the mineral maturity/crystallinity (MMC; determined by three methods: carbonate content, full width at half height of the v 1 PO4 band [FWHH], and wavelength at maxima of the v 1 PO4 band), as well as collagen maturity (ratio of pyridinoline/divalent cross-links), in paired iliac crest biopsies at trabecular, endosteal, and osteonal surfaces of newly formed bone in postmenopausal osteoporotic women who were previously either TN (n = 16) or receiving long-term ALN treatment (n = 24). RESULTS: Trabecular M/M ratio increased and matrix content decreased significantly in the ALN pretreated group. Collagen maturity decreased in both patient groups. Endosteal M/M ratio increased significantly in the TN group. Trabecular M/M ratio was higher at endpoint in the ALN pretreated group than in the TN group. Overall, no changes from baseline were observed in PG content, except that PG content was higher in the ALN pretreated group than in the TN group at endosteal surfaces at endpoint. The ability of TPTD treatment to reduce MMC in both patient groups and at the different bone surfaces depended on the measurement tool (relative carbonate content or wavelength at maxima of the v 1 PO4 band). None of the changes in MMC were different between the two patient groups. CONCLUSIONS: The results suggest some favorable impact of TPTD on bone mineral and organic matrix properties of in situ forming bone in terms of increased initial mineralization and decreased MMC and collagen maturity. Moreover, prior long-term ALN administration may have only limited influence on these properties in bone newly formed after 2 years of TPTD treatment.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Teriparatida/farmacologia , Idoso , Alendronato/administração & dosagem , Alendronato/uso terapêutico , Biópsia , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/uso terapêutico , Matriz Óssea/efeitos dos fármacos , Esquema de Medicação , Substituição de Medicamentos , Feminino , Humanos , Ílio/efeitos dos fármacos , Ílio/patologia , Ílio/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/patologia , Osteoporose Pós-Menopausa/fisiopatologia , Análise Espectral Raman/métodos , Teriparatida/administração & dosagem , Teriparatida/uso terapêutico
7.
Osteoporos Int ; 23(12): 2735-48, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22684497

RESUMO

Postmenopausal osteoporosis is mainly caused by increased bone remodeling resulting from estrogen deficiency. Indications for treatment are based on low areal bone mineral density (aBMD, T-score ≤ -2.5), typical fragility fractures (spine or hip), and more recently, an elevated 10-year fracture probability (by FRAX®). In contrast, there is no clear definition of osteoporosis nor intervention thresholds in younger individuals. Low aBMD in a young adult may reflect a physiologically low peak bone mass, such as in lean but otherwise healthy persons, whereas fractures commonly occur with high-impact trauma, i.e., without bone fragility. Furthermore, low aBMD associated with vitamin D deficiency may be highly prevalent in some regions of the world. Nevertheless, true osteoporosis in the young can occur, which we define as a T-score below -2.5 at spine or hip in association with a chronic disease known to affect bone metabolism. In the absence of secondary causes, the presence of fragility fractures, such as in vertebrae, may point towards genetic or idiopathic osteoporosis. In turn, treatment of the underlying condition may improve bone mass as well. In rare cases, a bone-specific treatment may be indicated, although evidence is scarce for a true benefit on fracture risk. The International Osteoporosis Foundation (IOF) convened a working group to review pathophysiology, diagnosis, and management of osteoporosis in the young, excluding children and adolescents, and provide a screening strategy including laboratory exams for a systematic approach of this condition.


Assuntos
Osteoporose/fisiopatologia , Adolescente , Densidade Óssea/fisiologia , Feminino , Predisposição Genética para Doença , Humanos , Osteoporose/diagnóstico , Osteoporose/etiologia , Osteoporose/terapia , Fraturas por Osteoporose/diagnóstico , Fraturas por Osteoporose/etiologia , Gravidez , Complicações na Gravidez/fisiopatologia , Adulto Jovem
8.
Osteoporos Int ; 23(12): 2885-91, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22426952

RESUMO

UNLABELLED: A 12-month morning teriparatide (TPTD) administration resulted in a larger increase in the lumbar spine bone mineral density (BMD) than the evening application. The results indicate that the response of bone cells to teriparatide treatment depends on dosing time. INTRODUCTION: The aim of this study was to assess the long-term effects of the morning vs. the evening teriparatide administration on BMD and bone turnover markers (BTMs) in postmenopausal osteoporosis. METHODS: Fifty women with established postmenopausal osteoporosis were randomized to 12-month treatment with 20 µg of TPTD, administered daily in the morning or in the evening. The BMD and serum concentrations of C-terminal telopeptide of type I collagen, N-terminal propeptide of type I procollagen (PINP), and tartrate-resistant acid phosphatase isoform 5b (TRAP 5b) were measured at baseline, after 6 and 12 months. General linear model-repeated measurements were used to analyze the data. RESULTS: After 12 months, the lumbar spine BMD grew markedly (p < 0.001) with a significantly greater increase in the morning arm compared to the evening arm (9.1% vs. 4.8%, respectively, p < 0.05). The BMD at the distal radius significantly decreased (p < 0.001), with no differences between the arms. The BMD at proximal femur did not change significantly. After 6 months, the BTMs were significantly increased compared with baseline (p < 0.001). The increases in the evening arm vs. the morning arm, however, were more pronounced in PINP (+358% vs. +215%, respectively) and in TRAP 5b (+70% vs. +37%, respectively) (both p < 0.05). CONCLUSION: 12-month morning administration of TPTD resulted in a larger increase in the lumbar spine BMD than the evening application. The timing of TPTD administration may be important for its efficacy.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Teriparatida/administração & dosagem , Fosfatase Ácida/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/uso terapêutico , Cálcio/sangue , Colágeno Tipo I/sangue , Esquema de Medicação , Feminino , Humanos , Injeções Subcutâneas , Isoenzimas/sangue , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/fisiopatologia , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Fosfatos/sangue , Pró-Colágeno/sangue , Fosfatase Ácida Resistente a Tartarato , Teriparatida/uso terapêutico
9.
Osteoporos Int ; 21(12): 2027-36, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20135094

RESUMO

SUMMARY: The level of increased bone formation after 24 months of treatment with teriparatide (rhPTH (1-34), TPTD) is similar in patients who were either treatment-naïve (TN) or had lower bone turnover initially due to previous alendronate (ALN) therapy. INTRODUCTION: Bone anabolic effects of TPTD in postmenopausal women with osteoporosis may be blunted during the initial phase after switching from ALN to TPTD. To explore the long-term implications, we examined histomorphometric and biochemical markers of bone turnover of patients on TPTD therapy after long-term ALN treatment. METHODS: Paired biopsies were obtained after tetracycline double labeling at baseline and after 24 months of TPTD treatment from 29 ALN-pretreated (64.5 ± 16.4 months) and 16 TN patients. Biochemical markers were measured at baseline, during the treatment, or at study end. RESULTS: Compared with the baseline, after 24-month TPTD, activation frequency (Ac.F.) and osteoid surface (OS) increased in both groups: 0.11-0.34 cycles per year, 3.96-9.8% in the ALN-pretreated group and 0.19-0.33 cycles per year, 6.2-11.3% (p < 0.05) in the TN group, respectively. Biochemical and histomorphometric markers correlated positively both at baseline and endpoint. Serum amino terminal propeptide of type I procollagen (PINP) correlated with Ac.F. (r = 0.57, p < 0.001 and r = 0.48, p < 0.01) and OS (r = 0.51, p < 0.01 and r = 0.56, p < 0.01) at baseline and endpoint, respectively. Following 3 months of treatment, increases in biochemical markers like PINP predicted the increase in Ac.F. (r = 0.52, p < 0.01) and OS (r = 0.54, p < 0.01) after 24 months. CONCLUSIONS: The increased level of formation is similar in patients who were either TN or had lower bone turnover initially due to previous ALN therapy. Elevated bone formation in postmenopausal women with osteoporosis was sustained over a 24-month period by TPTD. Biochemical markers of bone formation are a good surrogate for the assessment of TPTD effects.


Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológico , Teriparatida/uso terapêutico , Adulto , Idoso , Biomarcadores/sangue , Biópsia , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Substituição de Medicamentos , Feminino , Colo do Fêmur/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteogênese/efeitos dos fármacos , Osteoporose Pós-Menopausa/patologia , Osteoporose Pós-Menopausa/fisiopatologia , Resultado do Tratamento
10.
Bone ; 40(3): 662-73, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17175209

RESUMO

INTRODUCTION: While the determinants of BMD change have been studied in women, there have been few longitudinal studies in men. As part of the Network in Europe for Male Osteoporosis (NEMO) study, data were analysed from 1337 men and 1722 women aged 50-86y (mean=67 years) from 13 centres across Europe to assess determinants of BMD change and between-gender contrasts. METHODS: BMD was measured at the femoral neck, trochanter and/or L2-L4 spine on 2 occasions 0.8-8 years apart (mean=3.5 years) using DXA densitometers manufactured by Hologic (n=6), Lunar (n=5) and Norland (n=2). Each was cross-calibrated using the European Spine Phantom and annual rates of BMD change (g/cm(2)/year) were calculated from the standardised paired BMD values. The EPOS risk factor questionnaire was administered at baseline. RESULTS: In multivariate linear regression models, there were large between centre differences in the mean rates of BMD change in all 3 sites for both genders (P<0.0001) with the standard deviation of the between centre heterogeneity in the adjusted means being 0.005 g/cm(2)/year at the femoral neck. The overall adjusted mean annual rates of BMD change in g/cm(2)/year (95% CI) pooled across centres by random effects meta-analysis in men were: femoral neck -0.005 (-0.009, -0.001); trochanter -0.003 (-0.006, -0.001); and spine 0.000 (-0.004, 0.004). In women the respective estimates were: -0.007 (-0.009, -0.005); -0.004 (-0.006, -0.003); and -0.005 (-0.008, -0.001). The I(2) statistic for heterogeneity was between 81% and 94%, indicating strong evidence of between centre heterogeneity. Higher baseline BMD value was associated with subsequent greater decline in BMD (P<0.001). Preserved BMD was associated with higher baseline body weight in all 3 sites in men (P<0.012) but not in women. Weight gain preserved BMD (P<0.039) in all 3 sites for both genders, except the male spine. Increasing age was associated with faster BMD decline at the trochanter in both genders (P<0.026) and with a slower rate of decline at the female spine (P=0.002). Effects of lifestyle, physical activity, medications, and reproductive factors were not consistent across sites or between genders. CONCLUSION: These results show major geographic variations in rates of BMD change in men and women over 50 years of age across diverse European populations and demonstrate that body weight and weight gain are key determinants of BMD change in men.


Assuntos
Densidade Óssea/fisiologia , Quadril/fisiologia , Osteoporose/epidemiologia , Coluna Vertebral/fisiologia , Aumento de Peso/fisiologia , Absorciometria de Fóton , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Peso Corporal/fisiologia , Europa (Continente)/epidemiologia , Feminino , Fêmur/fisiologia , Humanos , Vértebras Lombares/fisiologia , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Inquéritos e Questionários
11.
Osteoporos Int ; 17(9): 1369-81, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16821002

RESUMO

INTRODUCTION: Vertebral fracture is a strong risk factor for future spine and hip fractures; yet recent data suggest that only 5-20% of subjects with a spine fracture are identified in primary care. We aimed to develop easily applicable algorithms predicting a high risk of future spine fracture in men and women over 50 years of age. METHODS: Data was analysed from 5,561 men and women aged 50+ years participating in the European Prospective Osteoporosis Study (EPOS). Lateral thoracic and lumbar spine radiographs were taken at baseline and at an average of 3.8 years later. These were evaluated by an experienced radiologist. The risk of a new (incident) vertebral fracture was modelled as a function of age, number of prevalent vertebral fractures, height loss, sex and other fracture history reported by the subject, including limb fractures occurring between X-rays. Receiver Operating Characteristic (ROC) curves were used to compare the predictive ability of models. RESULTS: In a negative binomial regression model without baseline X-ray data, the risk of incident vertebral fracture significantly increased with age [RR 1.74, 95% CI (1.44, 2.10) per decade], height loss [1.08 (1.04, 1.12) per cm decrease], female sex [1.48 (1.05, 2.09)], and recalled fracture history; [1.65 (1.15, 2.38) to 3.03 (1.66, 5.54)] according to fracture site. Baseline radiological assessment of prevalent vertebral fracture significantly improved the areas subtended by ROC curves from 0.71 (0.67, 0.74) to 0.74 (0.70, 0.77) P=0.013 for predicting 1+ incident fracture; and from 0.74 (0.67, 0.81) to 0.83 (0.76, 0.90) P=0.001 for 2+ incident fractures. Age, sex and height loss remained independently predictive. The relative risk of a new vertebral fracture increased with the number of prevalent vertebral fractures present from 3.08 (2.10, 4.52) for 1 fracture to 9.36 (5.72, 15.32) for 3+. At a specificity of 90%, the model including X-ray data improved the sensitivity for predicting 2+ and 1+ incident fractures by 6 and 4 fold respectively compared with random guessing. At 75% specificity the improvements were 3.2 and 2.4 fold respectively. With the modelling restricted to the subjects who had BMD measurements (n=2,409), the AUC for predicting 1+ vs. 0 incident vertebral fractures improved from 0.72 (0.66, 0.79) to 0.76 (0.71, 0.82) upon adding femoral neck BMD (P=0.010). CONCLUSION: We conclude that for those with existing vertebral fractures, an accurately read spine X-ray will form a central component in future algorithms for targeting treatment, especially to the most vulnerable. The sensitivity of this approach to identifying vertebral fracture cases requiring anti-osteoporosis treatment, even when X-rays are ordered highly selectively, exceeds by a large margin the current standard of practice as recorded anywhere in the world.


Assuntos
Algoritmos , Osteoporose/complicações , Osteoporose/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologia , Coluna Vertebral/diagnóstico por imagem , Fatores Etários , Idoso , Antropometria/métodos , Estatura , Densidade Óssea , Métodos Epidemiológicos , Europa (Continente)/epidemiologia , Feminino , Fêmur/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Radiografia , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/fisiopatologia , Coluna Vertebral/fisiopatologia
12.
Ann Rheum Dis ; 65(5): 654-61, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16339289

RESUMO

BACKGROUND: Reducing bisphosphonate dosing frequency may improve suboptimal adherence to treatment and therefore therapeutic outcomes in postmenopausal osteoporosis. Once-monthly oral ibandronate has been developed to overcome this problem. OBJECTIVE: To confirm the 1 year results and provide more extensive safety and tolerability information for once-monthly dosing by a 2 year analysis. METHODS: MOBILE, a randomised, phase III, non-inferiority study, compared the efficacy and safety of once-monthly ibandronate with daily ibandronate, which has previously been shown to reduce vertebral fracture risk in comparison with placebo. RESULTS: 1609 postmenopausal women were randomised. Substantial increases in lumbar spine bone mineral density (BMD) were seen in all treatment arms: 5.0%, 5.3%, 5.6%, and 6.6% in the daily and once-monthly groups (50 + 50 mg, 100 mg, and 150 mg), respectively. It was confirmed that all once-monthly regimens were at least as effective as daily treatment, and in addition, 150 mg was found to be better (p<0.001). Substantial increases in proximal femur (total hip, femoral neck, trochanter) BMD were seen; 150 mg produced the most pronounced effect (p<0.05 versus daily treatment). Independent of the regimen, most participants (70.5-93.5%) achieved increases above baseline in lumbar spine or total hip BMD, or both. Pronounced decreases in the biochemical marker of bone resorption, sCTX, observed in all arms after 3 months, were maintained throughout. The 150 mg regimen consistently produced greater increases in BMD and sCTX suppression than the 100 mg and daily regimens. Ibandronate was well tolerated, with a similar incidence of adverse events across groups. CONCLUSIONS: Once-monthly oral ibandronate is at least as effective and well tolerated as daily treatment. Once-monthly administration may be more convenient for patients and improve therapeutic adherence, thereby optimising outcomes.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológico , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Fêmur/fisiopatologia , Articulação do Quadril/fisiopatologia , Humanos , Ácido Ibandrônico , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/fisiopatologia , Resultado do Tratamento
13.
Bone ; 36(3): 387-98, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15777673

RESUMO

We have previously shown that center- and sex-specific fall rates explained one-third of between-center variation in upper limb fractures across Europe. In this current analysis, our aim was to determine how much of the between-center variation in fractures could be attributed to repeated falling, bone mineral density (BMD), and other risk factors in individuals, and to compare the relative contributions of center-specific BMD vs. center-specific fall rates. A clinical history of fracture was assessed prospectively in 2451 men and 2919 women aged 50-80 from 20 centers participating in the European Prospective Osteoporosis Study (EPOS) using standardized questionnaires (mean follow-up = 3 years). Bone mineral density (BMD, femoral neck, trochanter, and/or spine) was measured in 2103 men and 2565 women at these centers. Cox regression was used to model the risk of incident fracture as a function of the person-specific covariates: age, BMD, personal fracture history (PFH), family hip fracture history (FAMHIP), time spent walking/cycling, number of 'all falls' and falls not causing fracture ('fracture-free') during follow-up, alcohol consumption, and body mass index. Center effects were modeled by inclusion of multiplicative gamma-distributed random effects, termed center-shared frailty (CSF), with mean 1 and finite variance theta (theta) acting on the hazard rate. The relative contributions of center-specific fall risk and center-specific BMD on the incidence of limb fractures were evaluated as components of CSF. In women, the risk of any incident nonspine fracture (n = 190) increased with age, PFH, FAMHIP, > or =1 h/day walking/cycling, and number of 'all falls' during follow-up (all P < 0.074). 'Fracture-free' falls (P = 0.726) and femoral neck BMD did not have a significant effect at the individual level, but there was a significant center-shared frailty effect (theta = 0.271, P = 0.001) that was reduced by 4% after adjusting for mean center BMD and reduced by 19% when adjusted for mean center fall rate. Femoral trochanter BMD was a significant determinant of lower limb fractures (n = 53, P = 0.014) and the center-shared frailty effect was significant for upper limb fractures (theta = 0.271, P = 0.011). This upper limb fracture center effect was unchanged after adjusting for mean center BMD but was reduced by 36% after adjusting for center mean fall rates. In men, risk of any nonspine fracture (n = 75) increased with PFH, fall during follow-up (P < 0.026), and with a decrease in trochanteric BMD [RR 1.38 (1.08, 1.79) per 1 SD decrease]. There was no center effect evident (theta = 0.081, P = 0.096). We conclude that BMD alone cannot be validly used to discriminate between the risk of upper limb fractures across populations without taking account of population-specific variations in fall risk and other factors. These variations might reflect shared environmental or possibly genetic factors that contribute quite substantially to the risk of upper limb fractures in women.


Assuntos
Acidentes por Quedas , Densidade Óssea , Fraturas Ósseas/epidemiologia , Osteoporose/epidemiologia , Acidentes por Quedas/estatística & dados numéricos , Idoso , Densidade Óssea/fisiologia , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Valor Preditivo dos Testes , Estudos Prospectivos
14.
Calcif Tissue Int ; 76(2): 98-106, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15570400

RESUMO

To compare the ability of the bone mineral density (BMD) at the distal forearm, collagen I alpha 1 (COLIA1) polymorphism, and ultrasound stiffness to identify individuals with increased risk of wrist fracture, we studied 183 postmenopausal Czech women with a wrist fracture and 178 postmenopausal controls, ages 45-70 years. The genotypes "Ss" and "ss" were significantly overrepresented among fracture cases. The BMD measurements at the femoral neck, total femur, and distal forearm as well as ultrasound stiffness of the heel, broadband ultrasound attenuation (BUA), and speed of sound (SOS) were significantly lower in the fracture cohort. BMD of the distal forearm was the main determinant of susceptibility to the wrist fracture. Weight, the COLIA1 genotype, and ultrasound SOS further strengthened the predictive value of BMD. However, we found interaction between weight and both the COLIA1 Sp1 polymorphism and ultrasound parameters. Presence of the "s" allele as well as low SOS acted as significant predictors of wrist fracture only in heavier women, (> or =62 kg) but not in women with a body weight of less than 62 kg. In heavier women, both the COLIA1 Sp1 polymorphism and ultrasound parameters acted as independent markers that contributed to BMD to enhance fracture prediction. However, the COLIA1 enabled a higher specificity (specificity 72.4%, sensitivity 44.2%), whereas SOS enabled a higher sensitivity (sensitivity 73.9%, specificity, 45.7%). We conclude that BMD at total forearm, the COLIA1 polymorphism, and ultrasound SOS are independent predictors of wrist fracture in postmenopausal women. The effect of the COLIA1 Sp1 polymorphism and SOS on wrist fracture risk is more pronounced in patients with a higher body weight.


Assuntos
Peso Corporal , Calcâneo/diagnóstico por imagem , Colágeno Tipo I/genética , Fratura de Colles/genética , Fraturas Espontâneas/genética , Predisposição Genética para Doença , Polimorfismo Genético , Idoso , Densidade Óssea , Calcâneo/metabolismo , Estudos de Coortes , Colágeno Tipo I/metabolismo , Fratura de Colles/epidemiologia , Fratura de Colles/metabolismo , Feminino , Antebraço , Fraturas Espontâneas/epidemiologia , Fraturas Espontâneas/metabolismo , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/diagnóstico por imagem , Osteoporose Pós-Menopausa/epidemiologia , Osteoporose Pós-Menopausa/genética , Pós-Menopausa , Medição de Risco , Ultrassonografia
15.
Calcif Tissue Int ; 74(4): 377-81, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15255075

RESUMO

To elucidate the role of endogenous calcitonin (CT) in the regulation of bone resorption, we evaluated the acute effects of an intravenous calcium load in nine patients after total thyroidectomy (aged 29.2 +/- 8 years) compared with nine healthy subjects. After overnight fasting, intravenous infusions of elemental calcium 1.7 mg/kg body weight were given over a 10-minute period. Blood samples for measurements of serum ionized calcium (S-iCa), plasma intact CT, parathyroid hormone (PTH), and plasma type I collagen cross-linked C-terminal telopeptide (beta-CTX) were obtained 3 minutes before and at 13, 30, 60, 90, and 150 minutes after the start of the infusion. At baseline, parameters of calcium and bone metabolism were similar in both groups. A similar increase in S-iCa and decrease in plasma PTH levels were observed in both groups. However, the plasma CT increased significantly by 13 minutes (P < 0.05) and beta-CTX decreased significantly as early as 30 minutes (P < 0.05) (decrease by 36% as compared with the baseline) only in the group consisting of healthy individuals. In the thyroidectomized group, the plasma beta-CTX did not decrease significantly during the first 60 minutes (decrease by only 8% as compared with the baseline) and response to the calcium load was significantly diminished throughout the study period as compared with that of the healthy subjects (P < 0.01). In conclusion, the results indicate that the increased CT secretion is responsible for the rapid initial decrease in the bone resorption following an acute intravenous calcium load.


Assuntos
Reabsorção Óssea/tratamento farmacológico , Calcitonina/metabolismo , Cálcio/farmacologia , Osteoclastos/efeitos dos fármacos , Tireoidectomia , Adolescente , Adulto , Reabsorção Óssea/metabolismo , Calcitonina/sangue , Cálcio/administração & dosagem , Cálcio/sangue , Colágeno/sangue , Colágeno Tipo I , Feminino , Humanos , Infusões Intravenosas , Masculino , Osteoclastos/metabolismo , Hormônio Paratireóideo/sangue , Peptídeos/sangue
16.
Osteoporos Int ; 15(9): 760-5, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15138664

RESUMO

Vertebral fractures are associated with back pain and disability. There are, however, few prospective data looking at back pain and disability following identification of radiographic vertebral fracture. The aim of this analysis was to determine the impact of radiographically identified vertebral fracture on the subsequent occurrence of back pain and disability. Women aged 50 years and over were recruited from population registers in 18 European centers for participation in the European Prospective Osteoporosis Study. Participants completed an interviewer-administered questionnaire which included questions about back pain in the past year and various activities of daily living, and they had lateral spine radiographs performed. Participants in these centers were followed prospectively and had repeat spine radiographs performed a mean of 3.7 years later. In addition they completed a questionnaire with the same baseline questions concerning back pain and activities of daily living. The presence of prevalent and incident vertebral fracture was defined using established morphometric criteria. The data were analyzed using logistic regression with back pain or disability (present or absent) at follow-up as the outcome variable with adjustment made for the baseline value of the variable. The study included 2,260 women, mean age 62.2 years. The mean time between baseline and follow-up survey was 5.0 years. Two hundred and forty participants had prevalent fractures at the baseline survey, and 85 developed incident fractures during follow-up. After adjustment for age, center, and the baseline level of disability, compared with those without baseline prevalent fracture, those with a prevalent fracture (odds ratio [OR] = 1.4; 95% confidence interval [CI] 1.0 to 2.0) or an incident fracture (OR = 1.7; 95% CI, 0.9 to 3.2) were more likely to report disability at follow-up, though the confidence intervals embraced unity. Those with both a prevalent and incident fracture, however, were significantly more likely to report disability at follow-up (OR = 3.1; 95% CI, 1.4 to 7.0). After adjustment for age, center, and frequency of back pain at baseline, compared with those without baseline vertebral fracture, those with a prevalent fracture were no more likely to report back pain at follow-up (OR = 1.2; 95% CI, 0.8 to 1.7). There was a small increased risk among those with a preexisting fracture who had sustained an incident fracture during follow-up (OR = 1.6; 95% CI, 0.6 to 4.1) though the confidence intervals embraced unity. In conclusion, although there was no significant increase in the level of back pain an average of 5 years following identification of radiographic vertebral fracture, women who suffered a further fracture during follow-up experienced substantial levels of disability with impairment in key physical functions of independent living.


Assuntos
Dor nas Costas/etiologia , Avaliação da Deficiência , Fraturas da Coluna Vertebral/diagnóstico por imagem , Atividades Cotidianas , Idoso , Dor nas Costas/diagnóstico por imagem , Dor nas Costas/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Radiografia , Autoavaliação (Psicologia) , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/epidemiologia , Fatores de Tempo
17.
Ann Rheum Dis ; 62(10): 969-75, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12972476

RESUMO

OBJECTIVE: To investigate the efficacy, safety, and dose response of three doses of ibandronate, given intermittently by intravenous (IV) injection every three months, in preventing postmenopausal osteoporosis. PATIENTS AND METHODS: 629 postmenopausal women, categorised according to time since menopause and baseline lumbar spine (L1-4) bone mineral density (BMD), were enrolled into a multicentre, double blind, placebo controlled trial. They were randomly allocated to receive IV ibandronate 0.5 mg, 1 mg or 2 mg, or placebo every three months. All women received daily calcium supplementation. RESULTS: One year's treatment with intermittent IV ibandronate injections produced a dose dependent gain in mean (SD) lumbar spine BMD from baseline of 2.5 (2.5)%, 1.8 (2.6)%, and 1.0 (2.8)% in the groups receiving 2 mg, 1 mg, and 0.5 mg ibandronate, respectively, compared with a loss of BMD of 0.4 (2.4)% in the women in the placebo group; p=0.0001 for each ibandronate dose v placebo. Highest BMD gains occurred in women with osteopenia receiving 2 mg ibandronate. Similarly, at the hip, all three doses of ibandronate produced significantly better gains in BMD than placebo (p<0.05), with the greatest gains in the women with osteopenia receiving the 2 mg dose. Ibandronate concomitantly and dose dependently suppressed markers of bone turnover in comparison with placebo, and injections were well tolerated. CONCLUSION: IV ibandronate injections, given every three months, may be an effective alternative to oral bisphosphonates and hormonal therapy in the prevention of bone loss in postmenopausal women.


Assuntos
Difosfonatos/administração & dosagem , Osteoporose Pós-Menopausa/prevenção & controle , Fosfatase Alcalina/sangue , Biomarcadores/sangue , Biomarcadores/urina , Densidade Óssea , Colágeno/sangue , Colágeno/urina , Colágeno Tipo I , República Tcheca , Difosfonatos/uso terapêutico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Ácido Ibandrônico , Injeções Intravenosas , Vértebras Lombares , Pessoa de Meia-Idade , Noruega , Osteocalcina/sangue , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/fisiopatologia , Hormônio Paratireóideo/sangue , Peptídeos/sangue , Peptídeos/urina , Federação Russa , Estatísticas não Paramétricas
18.
J Bone Miner Res ; 18(9): 1664-73, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12968676

RESUMO

UNLABELLED: More severe vertebral fractures have more personal impact. In the European Prospective Osteoporosis Study, more severe vertebral collapse was predictable from prior fracture characteristics. Subjects with bi-concave or crush fractures at baseline had a 2-fold increase in incident fracture size and thus increased risk of a disabling future fracture. INTRODUCTION: According to Euler's buckling theory, loss of horizontal trabeculae in vertebrae increases the risk of fracture and suggests that the extent of vertebral collapse will be increased in proportion. We tested the hypothesis that the characteristics of a baseline deformity would influence the size of a subsequent deformity. METHODS: In 207 subjects participating in the European Prospective Osteoporosis Study who suffered an incident spine fracture in a previously normal vertebra, we estimated loss of volume (fracture size) from plane film images of all vertebral bodies that were classified as having a new fracture. The sum of the three vertebral heights (anterior, mid-body, and posterior) obtained at follow-up was subtracted from the sum of the same measures at baseline. Each of the summed height loss for vertebrae with a McCloskey-Kanis deformity on the second film was expressed as a percentage. RESULTS AND CONCLUSIONS: In univariate models, the numbers of baseline deformities and the clinical category of the most severe baseline deformity were each significantly associated with the size of the most severe incident fracture and with the cumulated sum of all vertebral height losses. In multivariate modeling, age and the clinical category of the baseline deformity (crush > bi-concave > uni-concave > wedge) were the strongest determinants of both more severe and cumulative height loss. Baseline biconcave and crush fractures were associated at follow-up with new fractures that were approximately twice as large as those seen with other types of deformity or who previously had undeformed spines. In conclusion, the characteristics of a baseline vertebral deformity determines statistically the magnitude of vertebral body volume lost when a subsequent fracture occurs. Because severity of fracture and number of fractures are determinants of impact, the results should improve prediction of the future personal impact of osteoporosis once a baseline prevalent deformity has been identified.


Assuntos
Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/patologia , Coluna Vertebral/patologia , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/metabolismo , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/metabolismo , Prognóstico , Estudos Prospectivos , Fraturas da Coluna Vertebral/metabolismo , Coluna Vertebral/metabolismo
20.
Osteoporos Int ; 14(1): 19-26, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12577181

RESUMO

The aim of this analysis was to determine the influence of lifestyle, anthropometric and reproductive factors on the subsequent risk of incident vertebral fracture in men and women aged 50-79 years. Subjects were recruited from population registers from 28 centers across Europe. At baseline, they completed an interviewer-administered questionnaire and had lateral thoraco-lumbar spine radiographs performed. Repeat spinal radiographs were performed a mean of 3.8 years later. Incident vertebral fractures were defined morphometrically and also qualitatively by an experienced radiologist. Poisson regression was used to determine the influence of the baseline risk factor variables on the occurrence of incident vertebral fracture. A total of 3173 men (mean age 63.1 years) and 3402 women (mean age 62.2 years) contributed data to the analysis. In total there were 193 incident morphometric and 224 qualitative fractures. In women, an age at menarche 16 years or older was associated with an increased risk of vertebral fracture (RR = 1.80; 95%CI 1.24, 2.63), whilst use of hormonal replacement was protective (RR = 0.58; 95%CI 0.34, 0.99). None of the lifestyle factors studied including smoking, alcohol intake, physical activity or milk consumption showed any consistent associations with incident vertebral fracture. In men and women, increasing body weight and body mass index were associated with a reduced risk of vertebral fracture though, apart from body mass index in men, the confidence intervals embraced unity. For most variables the strengths of the associations observed were similar using the qualitative and morphometric approaches to fracture definition. In conclusion our data suggest that modification of other lifestyle risk factors is unlikely to have a major impact on the population occurrence of vertebral fractures. The important biological mechanisms underlying vertebral fracture risk need to be explored using new investigational strategies.


Assuntos
Osteoporose/complicações , Fraturas da Coluna Vertebral/etiologia , Distribuição por Idade , Idoso , Antropometria/métodos , Índice de Massa Corporal , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/epidemiologia , Estudos Prospectivos , História Reprodutiva , Fatores de Risco , Distribuição por Sexo , Fraturas da Coluna Vertebral/epidemiologia
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