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1.
Curr Osteoporos Rep ; 17(6): 465-473, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31741221

RESUMO

PURPOSE OF REVIEW: The goal of the review is to assess the appropriateness of menopausal hormone therapy (MHT) for the primary prevention of bone loss in women at elevated risk in the early years after menopause. RECENT FINDINGS: Estrogen alone or combined with progestin to protect the uterus from cancer significantly reduces the risk of osteoporosis-related fractures. MHT increases type 1 collagen production and osteoblast survival and maintains the equilibrium between bone resorption and bone formation by modulating osteoblast/osteocyte and T cell regulation of osteoclasts. Estrogens have positive effects on muscle and cartilage. Estrogen, but not antiresorptive therapies, can attenuate the inflammatory bone-microenvironment associated with estrogen deficiency. However, already on second year of administration, MHT is associated with excess breast cancer risk, increasing steadily with duration of use. MHT should be considered in women with premature estrogen deficiency and increased risk of bone loss and osteoporotic fractures. However, MHT use for the prevention of bone loss is hindered by increase in breast cancer risk even in women younger than 60 years old or who are within 10 years of menopause onset.


Assuntos
Osso e Ossos/metabolismo , Neoplasias da Mama/epidemiologia , Terapia de Reposição de Estrogênios/métodos , Estrogênios/uso terapêutico , Osteoporose Pós-Menopausa/prevenção & controle , Fraturas por Osteoporose/prevenção & controle , Progestinas/uso terapêutico , Reabsorção Óssea , Colágeno Tipo I/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Osteoblastos , Osteoclastos , Osteócitos , Osteogênese , Osteoporose Pós-Menopausa/metabolismo , Medição de Risco , Linfócitos T , Resultado do Tratamento
2.
BMC Musculoskelet Disord ; 17: 308, 2016 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-27448601

RESUMO

BACKGROUND: Femoral neck fractures are a common occurrence in patients suffering from osteoporosis, while intracapsular hip fracture is rare in cases of osteoarthritis of the hip. Previous histomorphometric studies have emphasized the association between bone microarchitecture and the risk of low-impact fractures in osteoarthritis and osteoporosis patients. However, the strength of bone material is also a function of composition of organic bone matrix. In order to compare tissue material properties in these two clinical conditions, serum and bone pentosidine, a non-enzymatic collagen crosslinking element, was measured in patients who suffered a low-impact fracture, and in patients with advanced osteoarthritis. METHODS: The patient population consisted of 70 patients who underwent hemiarthroplasty surgery for a femoral neck fracture, and 41 patients with advanced hip joint osteoarthritis without a history of low- impact fracture, who were indicated for total hip joint replacement. Pentosidine content was analyzed in bone samples and in serum obtained from fracture and osteoarthritis patients using high performance liquid chromatography. RESULTS: Serum and bone concentrations of pentosidine were higher in subjects with hip fractures compared with osteoarthritis after adjustment for age, sex, weight, serum creatinine, and diabetes. A significant positive correlation was found between bone and serum pentosidine in fractured cases. A comparable relationship was also demonstrated for pentosidine levels in serum and bone relative to differentiation of fracture and osteoarthritis cases. CONCLUSIONS: Serum pentosidine can be considered a potential biomarker for identification of subjects with impaired bone quality and bone strength.


Assuntos
Arginina/análogos & derivados , Fraturas do Colo Femoral/sangue , Fêmur/química , Lisina/análogos & derivados , Osteoartrite do Quadril/sangue , Idoso , Idoso de 80 Anos ou mais , Arginina/sangue , Artroplastia de Quadril , Biomarcadores/sangue , Biópsia , Densidade Óssea , Cromatografia Líquida de Alta Pressão , Feminino , Fraturas do Colo Femoral/cirurgia , Fêmur/patologia , Humanos , Lisina/sangue , Masculino , Pessoa de Meia-Idade
3.
BMC Musculoskelet Disord ; 15: 51, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24558956

RESUMO

BACKGROUND: The study is aimed to evaluate body composition and bone status in adolescent and adult patients with active juvenile idiopathic arthritis (JIA) untreated with tumor necrosis factor alpha inhibitors. METHODS: Adult patients (12 male and 19 female) with active JIA and 84 healthy age- and gender- matched controls were enrolled into the study. Body composition (tissue mass in grams, lean mass, fat mass and bone mineral content as a fraction of tissue mass) and areal bone mineral density parameters (aBMD) at the lumbar spine, proximal femur, femoral neck, distal radius and total body were assessed using dual energy x-ray absorptiometry (DXA), and correlated with clinical characteristics of the disease and physical performance tests. Disease activity was assessed using high-sensitivity C-reactive protein (hsCRP) and disease activity score 28 (DAS 28). Differences between the groups were tested by t-test, and One-way ANOVA. Correlations were assessed using the Pearson correlation coefficients and multiple linear regression analysis. Significances were counted at the 0.05 level. RESULTS: In patients with clinically active JIA (DAS 28, 6.36 ± 0.64, hsCRP, 18.36 ± 16.95 mg/l), aBMD at all measured sites, bone mineral content (BMC) and lean mass were reduced, and fat mass was increased as compared with healthy controls. Significant negative correlations were observed between BMC and disease duration, use of glucocorticoids (GCs), and fat mass, respectively. A positive correlation was found between BMC and lean mass, and between the body fat fraction and the use of GCs. Using multiple linear regression analysis, lean mass was the only significant predictor of BMC of total body both in men and women, and of BMC of legs (only in men). Lean mass was also the only predicting factor of total proximal femur BMD and femoral neck BMD. No significant correlations have been determined among the body composition parameters and DAS 28 or hsCRP endpoints. CONCLUSIONS: In adult patients with long-term active JIA, lean mass was the main determining factor of total body and leg BMC, and total proximal femur and femoral neck aBMD.


Assuntos
Artrite Juvenil/patologia , Composição Corporal , Densidade Óssea , Absorciometria de Fóton , Adiposidade , Adolescente , Adulto , Idade de Início , Artrite Juvenil/metabolismo , Doenças Ósseas Metabólicas/etiologia , Proteína C-Reativa/análise , Estudos de Casos e Controles , Feminino , Fêmur/química , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Humanos , Perna (Membro) , Vértebras Lombares/química , Masculino , Atrofia Muscular/etiologia , Atrofia Muscular/patologia , Tamanho do Órgão , Especificidade de Órgãos , Aptidão Física , Rádio (Anatomia)/química , Adulto Jovem
4.
Calcif Tissue Int ; 92(4): 354-61, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23247536

RESUMO

The aim of this study was to investigate the acute effects of oral glucocorticoids in doses used in clinical practice on biochemical indices of the function of osteoclasts, osteoblasts, and osteocytes. In 17 adult patients suffering from various medical pathologies requiring systemic steroid therapy that were never before treated with glucocorticoids, glucocorticoid treatment was initiated (mean prednisolone equivalent dose of 23.1 ± 12.7 mg/day, range 10-50). Fasting morning serum concentrations of osteocalcin (OC), amino-terminal propeptide of type I procollagen (PINP), type 1 collagen cross-linked C-telopeptide (ßCTX), soluble receptor activator of nuclear factor kappaB ligand (sRANKL), osteoprotegerin (OPG), sclerostin, Dickkopf-1 (Dkk-1), and high-sensitivity C-reactive protein (hsCRP) were measured at baseline and on three consecutive days. Significant reductions in serum OC, PINP, OPG, sclerostin, and hsCRP were observed during 96 h of glucocorticoid administration, while serum ßCTX showed a significant percentual increase. A significant positive correlation was found between serum concentrations of Dkk-1 and ßCTX after 96 h of treatment with glucocorticoids. A significant drop in serum sclerostin, OPG, and OC observed in this study may reflect the rapid glucocorticoid-induced apoptosis of osteocytes.


Assuntos
Glucocorticoides/uso terapêutico , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteócitos/metabolismo , Doenças Reumáticas/sangue , Doenças Reumáticas/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Proteínas Morfogenéticas Ósseas/sangue , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Colágeno Tipo I/sangue , Relação Dose-Resposta a Droga , Feminino , Marcadores Genéticos , Glucocorticoides/farmacologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Masculino , Pessoa de Meia-Idade , Osteoblastos/efeitos dos fármacos , Osteocalcina/sangue , Osteoclastos/efeitos dos fármacos , Osteócitos/efeitos dos fármacos , Osteoprotegerina/sangue , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue , Estudos Prospectivos , Ligante RANK/sangue , Doenças Reumáticas/patologia
5.
J Bone Miner Metab ; 31(6): 606-12, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23925392

RESUMO

Strontium ranelate is a medicine with evidenced effects on the risk of fractures. The heterogeneity of strontium distribution in bone, quality of bone mineral crystals in young bone packets on bone surfaces formed during strontium ranelate administration, and activation of the calcium sensing receptor may, at least partially, explain the beneficial effects of SrR on reducing the risk of fractures. In this review, the concept of the dual action of strontium ranelate is also discussed. However, sufficient evidence for the bone anabolic effect of SrR does not exist in humans. The knowledge of the mechanism of action of SrR is important not only for the explanation of the effects of SrR upon the skeleton, but also for the safety of treatment for other tissues.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Fraturas Ósseas/induzido quimicamente , Tiofenos/efeitos adversos , Animais , Humanos
6.
Rheumatol Int ; 33(8): 2001-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23370856

RESUMO

Juvenile idiopathic arthritis (JIA) is an inflammatory disease associated with bone loss and low bone mineral density (BMD). The treatment involves disease-modifying antirheumatic drugs, glucocorticoids (GCs) and biological agents. The aim of this study was to evaluate effects of 12-month therapy with the anti-tumor necrosis factor alpha (anti-TNFα) preparations on bone mineral density (BMD) and biochemical turnover markers (BTM) in adult patients with JIA who were previously either treated or not treated with glucocorticoids (GC) and to assess effects of the discontinuation of GCs on their bone status. Nineteen adult patients (12 women, 7 men) aged 18-33 years with active JIA were prospectively enrolled to receive the anti-TNFα therapy (infliximab, etanercept or adalimumab). BMD and BTMs were determined at baseline and 1-year follow-up. The anti-TNFα therapy resulted in a significant reduction in disease activity score 28 (DAS28) and C-reactive protein (CRP) and a significant increase in BMD at the lumbar spine and total body and in serum N-terminal propeptide of type I procollagen (PINP, marker of bone formation). No significant changes in serum beta C-terminal telopeptide of type I collagen (ßCTX, marker of osteoclastic bone resorption) and osteocalcin (marker of bone remodeling) were found. A significant negative correlation was observed between the change in the DAS28, CRP and serum PINP. The change in serum PINP concentrations positively correlated with the change in lumbar spine BMD. A significant increase in serum PINP was observed only in patients discontinuing GCs during the anti-TNFα treatment. After the initiation of the anti-TNFα therapy in young adults with JIA, the increase in new bone formation can be explained by discontinuation of GCs administration as the patients with the largest reduction in DAS28 and CRP probably are the ones most likely to stop GC.


Assuntos
Antirreumáticos/farmacologia , Artrite Juvenil/tratamento farmacológico , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab , Adolescente , Adulto , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Juvenil/sangue , Artrite Juvenil/diagnóstico por imagem , Biomarcadores/sangue , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/diagnóstico por imagem , Proteína C-Reativa/metabolismo , Colágeno Tipo I/sangue , Etanercepte , Feminino , Humanos , Imunoglobulina G/farmacologia , Imunoglobulina G/uso terapêutico , Infliximab , Masculino , Osteocalcina/sangue , Pró-Colágeno/sangue , Radiografia , Receptores do Fator de Necrose Tumoral/uso terapêutico , Resultado do Tratamento
7.
Front Endocrinol (Lausanne) ; 14: 1139056, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033235

RESUMO

Aims: Ovarian hormone deficiency is one of the main risk factors for osteoporosis and bone fractures in women, and these risks can be mitigated by menopausal hormone therapy. Recent evidence suggests that gut microbiota may link changes in estrogen levels and bone metabolism. This study was conducted to investigate the potential relationship between hormonal and bone changes induced by oophorectomy and subsequent hormonal therapy and shifts in gut microbiota composition. Methods: We collected 159 stool and blood samples in several intervals from 58 women, who underwent bilateral oophorectomy. Changes in fecal microbiota were assessed in paired samples collected from each woman before and after oophorectomy or the start of hormone therapy. Bacterial composition was determined by sequencing the 16S rRNA gene on Illumina MiSeq. Blood levels of estradiol, FSH, biomarkers of bone metabolism, and indices of low-grade inflammation were measured using laboratory analytical systems and commercial ELISA. Areal bone mineral density (BMD) of the lumbar spine, proximal femur, and femur neck was measured using dual-energy X-ray absorptiometry. Results: We found no significant changes in gut microbiota composition 6 months after oophorectomy, despite major changes in hormone levels, BMD, and bone metabolism. A small decrease in bacterial diversity was apparent 18 months after surgery in taxonomy-aware metrics. Hormonal therapy after oophorectomy prevented bone loss but only marginally affected gut microbiota. There were no significant differences in ß-diversity related to hormonal status, although several microbes (e.g., Lactococcus lactis) followed estrogen levels. Body mass index (BMI) was the most significantly associated with microbiota variance. Microbiota was not a suitable predictive factor for the state of bone metabolism. Conclusions: We conclude that neither the loss of estrogens due to oophorectomy nor their gain due to subsequent hormonal therapy is associated with a specific gut microbiota signature. Sources of variability in microbiota composition are more related to interindividual differences than hormonal status.


Assuntos
Estradiol , Colo do Fêmur , Humanos , Feminino , Estudos Prospectivos , RNA Ribossômico 16S , Estrogênios
8.
Calcif Tissue Int ; 90(5): 365-72, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22399225

RESUMO

The aim of this study was to calculate rates of hospitalization for hip fracture and the incidence of hip fractures in the Czech Republic over a period of 29 years. A second aim was to use the most recent data to populate a FRAX(®) model for the assessment of fracture probability in individual patients. Data on hospitalizations for hip fracture (1981-2009) and number of women and men with hip fractures (2000-2009) were obtained, and incidences were computed for the entire population ≥50 years of age. Incidence of hospitalization for hip fracture in the Czech population aged ≥50 years increased progressively by calendar year. Age-standardized incidence of hip fractures increased to 2004 but leveled off thereafter and decreased after 2005. Data for hip fracture risk in 2008 and 2009 and the death hazard were used to populate a Czech-specific FRAX model for the computation of 10-year fracture probability. The customized FRAX model, using the verified epidemiological data, will be used to identify patients at increased fracture risk.


Assuntos
Fraturas do Quadril/epidemiologia , Idoso , Densidade Óssea/fisiologia , República Tcheca/epidemiologia , Feminino , Fraturas do Quadril/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/epidemiologia , Fatores de Risco
9.
Front Endocrinol (Lausanne) ; 13: 864299, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634507

RESUMO

Objective: Osteoporosis is associated with an impaired balance between bone resorption and formation, which in turn leads to bone loss and fractures. Many recent studies have underlined the regulatory role of microRNAs (miRNAs) in bone remodeling processes and their potential as biomarkers of osteoporosis. The purpose of this study was to prospectively examine the association of circulating miRNAs and bone biomarkers with estrogen status in women before and after oophorectomy, as well as in oophorectomized women on estrogen therapy. Methods: In this prospective study, we included 11 women before oophorectomy and hysterectomy and at 201 ± 24 days after the surgery. Another 11 women were evaluated 508 ± 127 days after oophorectomy and hysterectomy and after an additional 203 ± 71 days of estradiol treatment. Serum miRNAs were profiled by sequencing. Estrogen status and biomarkers of bone metabolism were quantified. Bone mineral density was assessed in the lumbar spine. Results: Our analysis revealed 17 miRNAs associated with estrogen levels. Of those miRNAs that were upregulated with estrogen deficiency and downregulated after estrogen therapy, miR-422a correlated with serum beta-carboxy-terminal type I collagen crosslinks (ß-CTX) and procollagen 1 N-terminal propeptide (P1NP); and miR-1278 correlated with serum ß-CTX, P1NP, osteocalcin, sclerostin, and Dickkopf-1(Dkk1). In contrast, we found an inverse association of miR-24-1-5p with estrogen status and a negative correlation with serum ß-CTX, P1NP, osteoprotegerin, and sclerostin levels. Conclusion: The reported miRNAs associated with estrogen status and bone metabolism could be potential biomarkers of bone pathophysiology and would facilitate studies on the prevention of postmenopausal osteoporosis. Our findings require validation in an extended cohort.


Assuntos
MicroRNAs , Osteoporose , Biomarcadores , Estrogênios , Feminino , Humanos , Menopausa , MicroRNAs/genética , Estudos Prospectivos
10.
Clin Chem Lab Med ; 50(2): 333-5, 2011 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-22080821

RESUMO

BACKGROUND: To investigate the mechanism by which strontium ranelate (SrR) inhibits the bone resorption, this study compared the effects of SrR and calcium on parathyroid hormone (PTH) and the biochemical marker of bone resorption (serum type 1 collagen cross-linked C-telopeptide, ßCTX). METHODS: In 10 healthy young subjects, after overnight fasting, 1000 mg of elemental calcium and 2000 mg of SrR containing 600 mg Sr²âº were administered consecutively with a 1 week washout period. During the control period no drug was given. Fasting blood samples were drawn at baseline and throughout the next 5-h period. RESULTS: After the ingestion of either calcium or SrR, there was a significant increase in serum calcium and strontium concentrations, and a decrease in serum ßCTX and intact PTH concentrations as compared to the baseline values (p<0.05). In the fasting subjects, no significant differences in the variable were found as compared to the baseline values. CONCLUSIONS: The decrease in PTH and the marker of bone resorption observed after the SrR administration is comparable to the decrease observed after the calcium administration in young adults.


Assuntos
Biomarcadores/sangue , Reabsorção Óssea/sangue , Cálcio/farmacologia , Colágeno Tipo I/sangue , Regulação da Expressão Gênica/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Hormônio Paratireóideo/sangue , Peptídeos/sangue , Tiofenos/farmacologia , Administração Oral , Adulto , Cálcio/sangue , Jejum , Feminino , Humanos , Masculino , Compostos Organometálicos/sangue , Padrões de Referência , Tiofenos/sangue , Adulto Jovem
11.
Arch Osteoporos ; 14(1): 10, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-30659410

RESUMO

PURPOSE: Using data from the 2-year, randomized, double-dummy VERO trial, we examined the changes in 25-hydroxy-vitamin D (25[OH]D) concentrations over time, and whether the fracture risk reduction of teriparatide versus risedronate varies by baseline 25(OH)D sufficiency category. METHODS: Postmenopausal women with established osteoporosis received subcutaneous daily teriparatide 20 µg or oral weekly risedronate 35 mg, with concomitant 500-1000 mg of elemental calcium and 400-800 IU/day of vitamin D supplements. Fracture endpoints were analyzed by predefined subgroups of 25(OH)D insufficient and sufficient patients. Heterogeneity of the treatment effect on fractures was investigated by logistic and Cox proportional hazards regression models. RESULTS: At baseline, mean serum 25(OH)D was 31.9 ng/mL in the teriparatide group and 31.5 ng/mL in the risedronate group, and 16.8% and 17.9% of patients, respectively, were 25(OH)D insufficient. At month 6, the mean serum 25(OH)D concentration decreased in teriparatide-treated patients to 24.5 ng/mL (by approximately 23%) but remained relatively constant in risedronate-treated patients (32.2 ng/mL) (p < 0.001). Proportions of 25(OH)D insufficient patients at month 6 were 26.7% and 5.6%, respectively (p < 0.001). The risk reduction with teriparatide versus risedronate for any of the fracture endpoints did not significantly differ between subgroups by 25(OH)D sufficiency status at baseline, with nonsignificant (p > 0.1) treatment-by-25(OH)D interactions in all fracture analyses. CONCLUSIONS: Serum 25(OH)D concentration decreases during teriparatide treatment. Fracture risk reduction with teriparatide versus risedronate did not significantly differ between the two groups of patients defined by baseline 25(OH)D. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01709110 EudraCT Number: 2012-000123-41.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osteoporose Pós-Menopausa/sangue , Fraturas por Osteoporose/etiologia , Ácido Risedrônico/uso terapêutico , Teriparatida/uso terapêutico , Vitamina D/análogos & derivados , Idoso , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/tratamento farmacológico , Vitamina D/sangue
12.
Bone ; 43(2): 332-339, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18519175

RESUMO

UNLABELLED: We collected population-based young normal hip and spine BMD data from 17 centres across Europe to assess between centre differences and to compare reference values with the US NHANES-III data. There was strong evidence of between country heterogeneity, but not between centres within countries. Hip BMD mean values were lower in European women, but SD's differed little from the NHANES-III USA results in both sexes. It may be necessary to adjust NHANES-III based T-scores by adding/subtracting a country-specific adjustment factor. INTRODUCTION: It remains unclear whether young normal BMD reference values specific to an American population can be validly used for T-score calculation in Europeans. METHODS: We collected population based BMD data from 1163 men and 329 women aged 19-29 years from 17 centres across Europe to compare mean and SD values with the NHANES-III study USA results. BMD(g/cm2) was measured at the hip and spine using DXA densitometers cross-calibrated with the European Spine Phantom (ESP). The only exclusions were for technically inadequate scans. A linear regression model was used to derive reference values. To allow for direct comparison with published NHANES III study data, the cross-calibrated BMD values were converted using the ESP equations to Hologic QDR 1000 units. RESULTS: In men, the overall mean(SD) BMD values expressed in Hologic-QDR1000 units of measurement, were: femoral neck 0.912(0.132); trochanter 0.793(0.124); and L2-L4 spine 1.027(0.123). The respective estimates in women were: 0.826(0.115); 0.670(0.093); and 0.983(0.107). However the I2 statistic for heterogeneity indicated moderate to strong evidence of between-centre heterogeneity. There was, however, no significant heterogeneity observed between centres within countries, suggesting that this variation arose from national differences. Compared to the NHANES III population-based US data, the mean values in women were significantly lower at both sites due to some lower national European means. However, at all sites and in both sexes the SD's were very similar between the US and Europe. There was some evidence that recruiting volunteers resulted in biased values in women. CONCLUSION: Our T-score normal values for the lumbar spine (L2-L4) should be more reliable for spine-specific risk assessment than some non-representative normal ranges, and should be evaluated for that purpose in Europe. If T-scores are to be used to compare individual data with ranges seen in normal young subjects of the same nationality, it may be necessary to adjust femoral NHANES III-based T-scores by adding (or subtracting) a country-specific adjustment factor. In risk assessment it is probably sufficient to use NHANES III-based hip T-scores, as supplied for the hip by densitometer manufacturers, interpreting them in light of recent international meta-analysis data on the relationship between BMD and fracture risk.


Assuntos
Absorciometria de Fóton , Densidade Óssea/fisiologia , Geografia , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Caracteres Sexuais , População Branca , Adulto , Estudos de Coortes , Intervalos de Confiança , Europa (Continente)/epidemiologia , Feminino , Colo do Fêmur/fisiopatologia , Inquéritos Epidemiológicos , Humanos , Masculino , Imagens de Fantasmas , Valores de Referência
13.
J Bone Miner Res ; 33(12): 2230-2235, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30102789

RESUMO

Teriparatide increases bone mass primarily through remodeling of older or damaged bone and abundant replacement with new mineralizing bone. This post hoc analysis investigated whether dual-energy X-ray absorptiometric (DXA) areal bone mineral density (aBMD) measurement adequately reflects changes of mineral and organic matrix content in cortical and trabecular bone. Paired biopsies and aBMD measurements were obtained before and at end of 2 years of teriparatide treatment from postmenopausal women with osteoporosis who were either alendronate pretreated (mean, 57.5 months) or osteoporosis-treatment naive. Biopsies were assessed by micro-computed tomography (µCT) to calculate mean cortical width (Ct.Wi), cortical area (Ct.Ar), and trabecular bone volume fraction (BV/TV). Fourier transformed infrared imaging (pixel size ∼6.3 × 6.3 µm2 ) was utilized to calculate mineral and organic matrix density (mean absorption/pixel), as well as total mineral and organic contents of cortical and cancellous compartments (sum of all pixels in the compartment). Effect of pretreatment over time was analyzed using mixed model repeated measures. µCT derived Ct.Wi and BV/TV increased, accompanied by similar increases in the overall mineral contents of their respective bone compartments. Mineral density did not change. Marked increases in the total content of both mineral and organic matrix associated with volumetric growth in both compartments consistently exceeded those of aBMD. Increases in organic matrix exceeded increases in mineral content in both cortical and trabecular compartments. For percent changes, only change in Ct.Wi correlated to change in femoral neck aBMD (r = .38, p = 0.043), whereas no other significant correlations of Ct.Wi or BV/TV with lumbar spine, total hip, or femoral neck aBMD were demonstrable. These data indicate that 2 years of teriparatide treatment leads to an increased bone organic matrix and mineral content in the iliac crest. The magnitude of these increases in the iliac crest were not detected with conventional aBMD measurements at other skeletal sites. © 2018 American Society for Bone and Mineral Research.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osso Esponjoso/diagnóstico por imagem , Osso Cortical/diagnóstico por imagem , Ílio/diagnóstico por imagem , Raios Infravermelhos , Teriparatida/farmacologia , Idoso , Osso Esponjoso/efeitos dos fármacos , Osso Cortical/efeitos dos fármacos , Feminino , Humanos , Ílio/efeitos dos fármacos , Imageamento Tridimensional , Pessoa de Meia-Idade , Tamanho do Órgão
14.
J Bone Miner Res ; 33(5): 783-794, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29329484

RESUMO

The 2-year, randomized, double-blind, active-controlled fracture endpoint VERO study included postmenopausal women with established osteoporosis, who had at least 2 moderate or 1 severe baseline vertebral fractures (VFx), and bone mineral density (BMD) T-score ≤-1.5. Patients were treated with either s.c. daily teriparatide 20 µg or oral weekly risedronate 35 mg. As previously reported, the risk of new VFx and clinical fractures (a composite of clinical VFx and nonvertebral fragility fractures [NVFFx]) was statistically significantly reduced with teriparatide compared with risedronate. Here we present the prospectively planned subgroup analyses of fracture data across subgroups, which were predefined by the following baseline characteristics: age, number and severity of prevalent VFx, prevalent nonvertebral fractures (NVFx), glucocorticoid use, prior osteoporosis drugs, recent bisphosphonate use, clinical VFx in the year before study entry, and baseline BMD. Heterogeneity of the treatment effect on the primary endpoint (new VFx), and the four key secondary endpoints (including clinical fractures and NVFFx) were investigated by logistic and Cox proportional hazards regression models. A total of 1360 women were randomized and treated (680 per group). Mean age was 72.1 years, mean (SD) number of prevalent VFx was 2.7 (2.1), 55.4% had a BMD T-score <-2.5, 36.5% had a recent clinical VFx, 28.3% had a prior major NVFx, 43.2% were osteoporosis drug-naïve, 39.3% were recent bisphosphonate users, and 9.3% were taking glucocorticoids at a prednisone-equivalent dose of >5 mg/d. For most fracture endpoints, the risk reduction of teriparatide versus risedronate did not significantly differ in any of the subgroups analyzed (treatment-by-subgroup interaction p > 0.1), with most subgroups mirroring results from the total study population. In conclusion, in postmenopausal women with severe osteoporosis, the antifracture efficacy of teriparatide compared with risedronate was consistent in a wide range of patient settings, including treatment-naïve and previously treated patients. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.


Assuntos
Osteoporose/tratamento farmacológico , Pós-Menopausa , Ácido Risedrônico/administração & dosagem , Fraturas da Coluna Vertebral/tratamento farmacológico , Teriparatida/administração & dosagem , Idoso , Método Duplo-Cego , Feminino , Humanos , Osteoporose/metabolismo , Osteoporose/patologia , Fatores de Risco , Fraturas da Coluna Vertebral/metabolismo , Fraturas da Coluna Vertebral/patologia
15.
Bone ; 41(3): 378-85, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17597017

RESUMO

Marked suppression of bone turnover by bisphosphonates is associated with increased bone microdamage accumulation in animal models. The purpose of this study was to test the hypothesis that long-term treatment with alendronate (ALN) results in accumulation of microdamage in bone in women after menopause. Sixty-six postmenopausal women with osteoporosis (mean age of 68.0 years and mean BMD T-score of -1.7 at total hip and -2.8 at lumbar spine; 62% with prevalent fractures) were evaluated in this cross-sectional analysis. Thirty-eight had been treated previously with ALN (10 mg/day or 70 mg/week for a mean duration of 63.6 months) while twenty-eight were treatment naive (TN). Without adjustments, crack surface density (Cr.S.Dn) and crack density (Cr.Dn) were not different between ALN and TN patients. After adjustment for potential confounders (age, prevalent fractures, femoral neck BMD, activation frequency and center), Cr.Dn was elevated in ALN patients (P=0.028 and P=0.069 for Cr.S.Dn). In ALN patients only, lower femoral neck BMD (Cr.S.Dn, r=-0.58, P=0.003; Cr.Dn, r=-0.54, P=0.005) and increased age (Cr.S.Dn, r=0.43, P=0.03; Cr.Dn, r=0.43, P=0.03) were associated with microdamage accumulation. Among potential confounders, femoral neck BMD was the only independent predictor for these correlations (P=0.04 for Cr.Dn and P=0.03 for Cr.S.Dn). We conclude that increased microdamage accumulation may occur in low BMD patients treated with alendronate.


Assuntos
Alendronato/efeitos adversos , Conservadores da Densidade Óssea/efeitos adversos , Densidade Óssea/fisiologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Osteoporose Pós-Menopausa/tratamento farmacológico , Fatores Etários , Idoso , Densidade Óssea/efeitos dos fármacos , Estudos Transversais , Feminino , Humanos , Pós-Menopausa
16.
Arch Osteoporos ; 12(1): 49, 2017 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-28812252

RESUMO

Despite individual recommendations on osteoporosis management in patients after hip fracture surgery, addressed by orthopedic surgeons to Czech general practitioners, the patients remained undiagnosed and untreated because of provider-level barriers to post-fracture secondary prevention. PURPOSE: The goal of the study was to assess whether an individual recommendation on osteoporosis treatment addressed to a hip fracture patient's GP would lead to better osteoporosis management. METHODS: Two groups of patients who suffered hip fractures and were treated at the Orthopedic Department were evaluated. In 111 patients, general recommendations on osteoporosis treatment and fracture prevention were provided in a discharge report addressed to the GP. In the second group, 96 patients were provided individually with a detailed written set of recommendations on osteoporosis examination, treatment, and fracture prevention, which was also provided in the discharge report. A questionnaire to assess the provided care was mailed to the patients 5.3 ± 1.2 months of discharge. Those patients who did not return the questionnaires were contacted by phone. RESULTS: The questionnaires were received from 44% and 49% of patients from the general and detailed recommendation groups, respectively. Along with the phone call, we were able to contact 78 (70.3%) and 68 (70.8%) patients from the general and detailed recommendation groups, respectively. GPs secured osteoporosis evaluation in 14.6% of the patients. Calcium supplementation and vitamin D supplementation were newly provided in 42.7 and 36.4% of the patients, respectively. Anti-resorptive therapy was newly provided in 8.3% of the patients. No significant differences between the groups were observed in osteoporosis evaluation, calcium and vitamin D supplementation, and anti-osteoporosis treatments. Out of 207 patients, further examination or treatment was requested by 45 patients (21.7%); 75 patients (36.2%) declared no interest in further care. CONCLUSION: Recommendations on osteoporosis management addressed to Czech GPs after surgical fracture management had little effect on treatment. As the anti-osteoporotic preparations can only be prescribed by specialists, the availability of necessary examinations and treatment is limited by the motivation of GPs. Consequently, the implementation of Fracture Liaison Services to help close the care gap may be limited in the absence of participation by Czech GPs.


Assuntos
Medicina Geral/métodos , Fraturas do Quadril/cirurgia , Osteoporose/terapia , Fraturas por Osteoporose/prevenção & controle , Prevenção Secundária/métodos , Idoso , Comportamento Cooperativo , República Tcheca , Suplementos Nutricionais/estatística & dados numéricos , Feminino , Fraturas do Quadril/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Período Pós-Operatório , Inquéritos e Questionários
17.
J Bone Miner Res ; 32(5): 1040-1051, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28019683

RESUMO

We present final results of a study comparing teriparatide 20 µg every day (QD) with risedronate 35 mg once per week (QW) started within 2 weeks after surgery for a pertrochanteric hip fracture. Patients with BMD T-score ≤ -2.0 and 25OHD ≥9.2 ng/mL were randomized to receive 26-week double-dummy treatment plus calcium and vitamin D, followed by 52-week open-label treatment with the same assigned active drug. Primary endpoint was change from baseline in lumbar spine (LS) BMD at 78 weeks. Secondary and exploratory endpoints were change in BMD at the proximal femur, function, hip pain (Charnley score and 100 mm Visual Analog Scale [VAS]), quality of life (Short Form-36), radiology outcomes, and safety. Data were analyzed with mixed models for repeated measures (MMRM) and logistic regression. Totally, 224 patients were randomized; 171 (teriparatide: 86) contributed to the efficacy analyses (mean ± SD age: 77 ± 7.7 years, 77% females). Mean baseline LS, femoral neck (FN), and total hip (TH) T-scores were -2.16, -2.63, and -2.51, respectively. At 78 weeks, BMD increased significantly more with teriparatide compared to risedronate at the LS (+11.08% versus +6.45%; p < 0.001) and FN (+1.96% versus -1.19%; p = 0.003), with no significant between-group difference in TH BMD. Timed up-and-go (TUG) test was significantly faster with teriparatide at 6, 12, 18, and 26 weeks (differences: -3.2 to -5.9 s; p = 0.045 for overall difference). Hip pain during TUG test by 100 mm VAS was significantly lower with teriparatide at 18 weeks (adjusted difference: -11.3 mm, p = 0.033; -10.0 and -9.3 mm at 12 and 26 weeks, respectively; p = 0.079 for overall difference). Other secondary and exploratory outcomes were not different. Teriparatide group showed two new hip fractures versus seven with risedronate (p = 0.171) and more frequent hypercalcemia and hyperuricemia. In conclusion, 78-week treatment with teriparatide showed significantly greater increases in LS and FN BMD, less pain, and a faster TUG test versus risedronate. © 2016 American Society for Bone and Mineral Research.


Assuntos
Fraturas do Quadril/tratamento farmacológico , Ácido Risedrônico/administração & dosagem , Teriparatida/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Fraturas do Quadril/sangue , Fraturas do Quadril/patologia , Humanos , Estudos Prospectivos , Ácido Risedrônico/efeitos adversos , Teriparatida/efeitos adversos , Fatores de Tempo
18.
Bone ; 94: 124-134, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27777119

RESUMO

BACKGROUND: Hip fractures are mainly caused by accidental falls and trips, which magnify forces in well-defined areas of the proximal femur. Unfortunately, the same areas are at risk of rapid bone loss with ageing, since they are relatively stress-shielded during walking and sitting. Focal osteoporosis in those areas may contribute to fracture, and targeted 3D measurements might enhance hip fracture prediction. In the FEMCO case-control clinical study, Cortical Bone Mapping (CBM) was applied to clinical computed tomography (CT) scans to define 3D cortical and trabecular bone defects in patients with acute hip fracture compared to controls. Direct measurements of trabecular bone volume were then made in biopsies of target regions removed at operation. METHODS: The sample consisted of CT scans from 313 female and 40 male volunteers (158 with proximal femoral fracture, 145 age-matched controls and 50 fallers without hip fracture). Detailed Cortical Bone Maps (c.5580 measurement points on the unfractured hip) were created before registering each hip to an average femur shape to facilitate statistical parametric mapping (SPM). Areas where cortical and trabecular bone differed from controls were visualised in 3D for location, magnitude and statistical significance. Measures from the novel regions created by the SPM process were then tested for their ability to classify fracture versus control by comparison with traditional CT measures of areal Bone Mineral Density (aBMD). In women we used the surgical classification of fracture location ('femoral neck' or 'trochanteric') to discover whether focal osteoporosis was specific to fracture type. To explore whether the focal areas were osteoporotic by histological criteria, we used micro CT to measure trabecular bone parameters in targeted biopsies taken from the femoral heads of 14 cases. RESULTS: Hip fracture patients had distinct patterns of focal osteoporosis that determined fracture type, and CBM measures classified fracture type better than aBMD parameters. CBM measures however improved only minimally on aBMD for predicting any hip fracture and depended on the inclusion of trabecular bone measures alongside cortical regions. Focal osteoporosis was confirmed on biopsy as reduced sub-cortical trabecular bone volume. CONCLUSION: Using 3D imaging methods and targeted bone biopsy, we discovered focal osteoporosis affecting trabecular and cortical bone of the proximal femur, among men and women with hip fracture.


Assuntos
Fraturas do Quadril/etiologia , Osteoporose/complicações , Idoso , Área Sob a Curva , Biópsia , Osso Cortical/patologia , Feminino , Colo do Fêmur/patologia , Fraturas do Quadril/patologia , Humanos , Masculino , Razão de Chances , Osteoporose/patologia , Curva ROC
19.
J Clin Endocrinol Metab ; 91(3): 870-7, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16352692

RESUMO

OBJECTIVE: The aim of this study was to compare bone mineral density (BMD) and biochemical markers of bone turnover in patients receiving long-term alendronate therapy who continued alendronate, were switched to raloxifene, or discontinued antiresorptive therapy. DESIGN, PATIENTS, AND INTERVENTIONS: Ninety-nine ambulatory women who were diagnosed with postmenopausal osteoporosis and treated with alendronate (10 mg/d) for a mean period of 43 months were randomized to double-blind raloxifene (60 mg/d; n = 33), placebo (n = 33), or continuation of open-label alendronate (n = 33) for 12 months. Patients continued their assigned treatment in a subsequent 12-month, open-label extension phase. All patients received supplemental calcium (500 mg/d) and vitamin D (800 IU/d). MAIN OUTCOME MEASURES: BMD (lumbar spine, total femur, femoral neck, distal forearm, and total body) and biochemical markers (serum intact amino-terminal propeptide of type I procollagen, type 1 collagen cross-linked C-telopeptide, and osteocalcin) were measured at baseline and follow-up visits. RESULTS: Discontinuation of alendronate therapy resulted in a decrease in lumbar spine BMD at 12 months (-2.66%; P < 0.05), but did not change total femur BMD (+0.35%; nonsignificant). Raloxifene and alendronate, compared with discontinuation, prevented lumbar spine BMD loss (-0.75% and -0.54% at 12 months, respectively; P < 0.05). Raloxifene and alendronate caused a similar increase in total femur BMD at 12 months (1.45% and 1.56%; both P < 0.05 vs. baseline; nonsignificant vs. discontinuation). Patients, who discontinued alendronate therapy experienced an increase in bone turnover. Bone turnover increases were less pronounced in patients taking raloxifene and were absent in those who continued alendronate. Of the three groups, mean bone turnover in raloxifene patients was the closest to premenopausal mean values. CONCLUSIONS: BMD preservation and increase were most pronounced in patients continuing alendronate. Raloxifene treatment, compared with placebo, demonstrated beneficial effects on BMD and bone turnover after discontinuation of long-term alendronate therapy.


Assuntos
Alendronato/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológico , Cloridrato de Raloxifeno/uso terapêutico , Alendronato/administração & dosagem , Conservadores da Densidade Óssea/uso terapêutico , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Placebos , Cloridrato de Raloxifeno/administração & dosagem
20.
Bone ; 89: 16-24, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27185100

RESUMO

An increase in procollagen type I amino-terminal propeptide (PINP) early after teriparatide initiation was shown to correlate with increased lumbar spine areal BMD and is a good predictor of the anabolic response to teriparatide. Few data exist correlating PINP and bone microstructure, and no data exist in patients on teriparatide following prior potent antiresorptive treatment. This exploratory analysis aimed to investigate the effects of teriparatide on cancellous bone microstructure and correlations of bone markers with microstructure in alendronate-pretreated patients. This was a post hoc analysis of changes in bone markers and three-dimensional indices of bone microstructure in paired iliac crest biopsies from a prospective teriparatide treatment study in postmenopausal women with osteoporosis who were either treatment-naïve (TN, n=16) or alendronate-pretreated (ALN, n=29) at teriparatide initiation. Teriparatide (20µg/day) was given for 24months; biopsies were taken at baseline and endpoint, and serum concentrations of PINP and type 1 collagen cross-linked C-telopeptide (ßCTX) were measured at intervals up to 24months. In the TN and ALN groups, respectively, mean (SD) increases in three-dimensional bone volume/tissue volume were 105 (356)% (P=0.039) and 55 (139)% (P<0.005) and trabecular thickness 30.4 (30)% (P<0.001) and 30.8 (53)% (P<0.001). No significant changes were observed in trabecular number or separation. In the ALN patients, 3-month change of neither PINP nor ßCTX correlated with indices of cancellous bone microstructure. However, 12-month changes in biochemical bone markers correlated significantly with improvements in bone volume/tissue volume, r=0.502 (P<0.01) and r=0.378 (P<0.05), trabecular number, r=0.559 (P<0.01) and r=0.515 (P<0.01), and reduction of trabecular separation, r=-0.432 (P<0.05) and r=-0.530 (P<0.01), for PINP and ßCTX, respectively. We conclude that cancellous bone microstructure improved with teriparatide therapy irrespective of prior antiresorptive use.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Osso Esponjoso/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Teriparatida/uso terapêutico , Idoso , Alendronato/uso terapêutico , Remodelação Óssea/efeitos dos fármacos , Colágeno Tipo I/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue
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