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1.
Eur J Endocrinol ; 189(3): 346-354, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37633255

RESUMO

OBJECTIVE: To determine mechanisms contributing to impaired bone health in youth 24 months following sleeve gastrectomy (SG). DESIGN: Twenty-four-month longitudinal observational study. METHODS: Participants included 23 youth undergoing SG and 30 non-surgical controls (NS) 13-25 years old with moderate-to-severe obesity. Subjects underwent fasting labs for bone turnover markers (N-terminal propeptide of type 1 procollagen, C-telopeptide (CTX)), sex hormones, sex hormone binding globulin (SHBG), and enteric peptides, DXA for areal bone mineral density (aBMD) and body composition, high-resolution peripheral quantitative CT for volumetric BMD (vBMD) at the distal radius and tibia, and microfinite element analysis for strength estimates. RESULTS: Groups did not differ for mean age or BMI z-scores. Over 24 months, compared to NS, SG had greater reductions in BMI z-scores, and spine, hip, and femoral neck aBMD Z-scores (P ≤ .012), greater increases in serum CTX and SHBG (P ≤ .039), and greater decreases in estrone and ghrelin (P ≤ .021). Among females, estrone and free androgen index (FAI) decreased (P ≤ .022) in SG vs NS groups. After controlling for age and sex, decreases in BMI and lean mass were associated with decreases in total hip and femoral neck aBMD Z-scores, and decreases in radial total and trabecular vBMD and failure load, and tibial total and trabecular vBMD. Among females, after controlling for age, decreases in estrone were associated with decreases in spine aBMD Z-scores and radial total and trabecular vBMD, and decrease in FAI with decreases in radial failure load. CONCLUSION: Reductions in BMI, lean mass, and sex steroids over 24 months post-SG are associated with bone loss and could be targeted for preventative or therapeutic interventions. Clinical trial registration number: The study is registered in ClinicalTrials.gov (NCT02557438).


Assuntos
Estrona , Coluna Vertebral , Feminino , Adolescente , Humanos , Adulto Jovem , Adulto , Densidade Óssea , Composição Corporal , Gastrectomia
2.
Cytokine ; 148: 155685, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34411988

RESUMO

The progression of chronic kidney disease (CKD) in children is associated with deregulated parathyroid hormone (PTH), growth retardation, and low bone accrual. PTH can cause both catabolic and anabolic impact on bone, and the activating transcription factor 4 (ATF4), a downstream target gene of PTH, is related to its anabolic effect. Osteoprotegerin (OPG) and receptor activator of NF-κB ligand (RANKL) are PTH-dependent cytokines, which may play an important role in the regulation of bone remodeling. This study aimed to evaluate the impact of endogenous PTH and the bone RANKL/OPG system on bone growth, cross-sectional geometry and strength utilizing young, nephrectomized rats. The parameters of cross-sectional geometry were significantly elevated in rats with CKD during the three-month experimental period compared with the controls, and they were strongly associated with serum PTH levels and the expression of parathyroid hormone 1 receptor (PTH1R)/ATF4 genes in bone. Low bone soluble RANKL (sRANKL) levels and sRANKL/OPG ratios were also positively correlated with cross-sectional bone geometry and femoral length. Moreover, the analyzed geometric parameters were strongly related to the biomechanical properties of femoral diaphysis. In summary, the mild increase in endogenous PTH, its anabolic PTH1R/ATF4 axis and PTH-dependent alterations in the bone RANKL/OPG system may be one of the possible mechanisms responsible for the favorable impact on bone growth, cross-sectional geometry and strength in young rats with experimental CKD.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Desenvolvimento Ósseo , Osso e Ossos/patologia , Osteoprotegerina/metabolismo , Hormônio Paratireóideo/sangue , Ligante RANK/metabolismo , Receptores de Hormônios Paratireóideos/metabolismo , Insuficiência Renal Crônica/sangue , Fator 4 Ativador da Transcrição/genética , Animais , Fenômenos Biomecânicos , Osso e Ossos/metabolismo , Fêmur/patologia , Fêmur/fisiopatologia , Regulação da Expressão Gênica , Hormônio Paratireóideo/genética , Ratos , Receptores de Hormônios Paratireóideos/genética , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/fisiopatologia , Solubilidade
3.
Bone ; 134: 115290, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32084562

RESUMO

BACKGROUND: Sleeve gastrectomy is the most commonly performed weight loss surgery in adolescents with moderate-to-severe obesity. While studies in adults have reported on the deleterious effects of gastric bypass surgery on bone structure and strength estimates, data are lacking for the impact of sleeve gastrectomy on these measures in adolescents. OBJECTIVE: To evaluate the impact of sleeve gastrectomy on bone outcomes in adolescents and young adults over 12 months using dual energy X-ray absorptiometry (DXA) and high resolution peripheral quantitative computed tomography (HRpQCT). PARTICIPANTS AND METHODS: We enrolled 44 youth 14-22 years old with moderate to severe obesity; 22 underwent sleeve gastrectomy and 22 were followed without surgery (16 females and 6 males in each group). At baseline and 12 months, DXA was used to assess areal bone mineral density (aBMD), HRpQCT of the distal radius and tibia was performed to assess bone geometry, microarchitecture and volumetric BMD (vBMD), and finite element analysis to assess strength estimates (stiffness and failure load). These analyses were adjusted for age, sex, race and the bone measure at baseline. Fasting blood samples were assessed for calcium, phosphorus, and 25(OH) vitamin D (25OHD) levels. RESULTS: Over 12-months, the surgical group lost 27.2% of body weight compared to 0.1% in the non-surgical (control) group. Groups did not differ for changes in 25OHD levels (p = 0.186). Compared to controls, the surgical group had reductions in femoral neck and total hip aBMD Z-scores (p ≤ 0.0006). At the distal tibia, compared to controls, the surgical group had reductions in cortical area and thickness and trabecular number, and increases in trabecular area and separation (p ≤ 0.026). At the distal radius, the surgical group had greater reductions in trabecular vBMD, than controls (p = 0.010). The surgical group had an increase in cortical vBMD at both sites (p ≤ 0.040), possibly from a decrease in cortical porosity (p ≤ 0.024). Most, but not all, differences were attenuated after adjusting for 12-month change in BMI. Groups did not differ for changes in strength estimates over time, except that increases in tibial stiffness were lower in the surgical group (p = 0.044) after adjusting for 12-month change in BMI. CONCLUSIONS: Over 12 months, weight loss associated with sleeve gastrectomy in adolescents had negative effects on areal BMD and certain HRpQCT parameters. However, bone strength estimates remained stable, possibly because of a simultaneous decrease in cortical porosity and increase in cortical volumetric BMD. Additional research is necessary to determine the relative contribution(s) of weight loss and the metabolic effects of surgery on bone outcomes, and whether the observed effects on bone stabilize or progress over time.


Assuntos
Densidade Óssea , Gastrectomia , Obesidade , Rádio (Anatomia) , Absorciometria de Fóton , Adolescente , Feminino , Humanos , Masculino , Obesidade/cirurgia , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/cirurgia , Tíbia , Adulto Jovem
4.
Orthop Traumatol Surg Res ; 104(7): 997-1001, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30243675

RESUMO

BACKGROUND: The posterior condylar angle (PCA) is formed by the posterior condylar line (PCL) and the clinical (or anatomic) transepicondylar line (TEL). The primary objective of this study was to compare the distribution of PCA values in Caucasians and Asians free of knee osteoarthritis. The secondary objectives were to assess PCA variability according to age, gender, and side. HYPOTHESIS: PCA values differ between Caucasians and Asians. METHODS: The study included the computed tomography scans of 515 healthy femurs, 259 from Asians in China and 256 from Caucasians in France. PCA values were determined based on four landmarks, namely, the two femoral epicondyles and the most prominent point of each condyle at the posterior aspect of the knee. The Mann-Whitney test was chosen to compare PCA values according to ethnic group, gender, and side and Spearman's correlation coefficient to assess correlations with age. Inter-observer and intra-observer variability of PCA measurements was assessed. RESULTS: Mean PCA was 6.0°±2.5° (range, 0°-14°) overall, 6.4° (range, 0.31°-14.1°) in the Asians, and 5.5° (range, 0°-13.1°) in the Caucasians (p<0.0001). Chinese femurs are significantly more internally rotated. No differences in PCA values were found according to age (p=0.4307), gender (p=0.7113), or side (p=0.4304). Inter-observer and intra-observer variability was limited for each of the landmarks, indicating that PCA measurement was reliable. CONCLUSION: PCA varies not only across individuals as reported previously, but also across ethnic groups. This finding further supports routine PCA measurement on imaging studies before total knee arthroplasty. LEVEL OF EVIDENCE: III, comparative retrospective study.


Assuntos
Povo Asiático , Fêmur/anatomia & histologia , Fêmur/diagnóstico por imagem , População Branca , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos , Anatomia Comparada , China , Feminino , França , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Retrospectivos , Fatores Sexuais , Tomografia Computadorizada por Raios X , Adulto Jovem
5.
J Nutr Health Aging ; 22(2): 216-221, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29380848

RESUMO

OBJECTIVES: Previous studies found that tea consumption was related to a reduction in the risks of some chronic diseases, but limited data are available on bone health. This study aimed to examine the associations of tea consumption with hip bone strength in Chinese women. DESIGN: Cross-sectional study. SETTING: The participants were from the ongoing Guangzhou Nutrition and Health Study. This was a cohort study started in 2008. The examination data conducted between June 2010 and December 2013 were used. PARTICIPANTS: A total of 1,495 Chinese women aged more than 40 years were included. MEASUREMENTS: Tea consumption, socio-demographic information and lifestyle habits were collected by a face-to-face questionnaire. Hip bone mineral density (BMD) and geometric parameters, i.e. cross-sectional area (CSA), section modulus (Z) and buckling ratio (BR), were generated by dual-energy X-ray absorptiometry. The associations of tea consumption with bone phenotypes were detected by analysis of covariance and multiple linear regression models after adjusting for age, body mass index, years since menopause, physical activity, dietary-protein intake, dietary-calcium intake, calcium tablet intake, drinking status and smoking status. RESULTS: Tea drinkers (n = 732) had approximately 1.9% higher BMD (p < 0.05) and 3.6% lower BR (p < 0.05) than non-tea drinkers (n = 763). The dose-response relationships of BMD, BR or CSA with total tea consumption were identified (p-trend < 0.05). Tea drinking was found to be a significant and independent predictor of BMD (ß = 0.068, p < 0.05) or BR (ß = -0.079, p < 0.05). CONCLUSION: Tea consumption was associated with increased bone strength in middle-aged and elderly Chinese women.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osteoporose/prevenção & controle , Chá/química , Povo Asiático , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade
6.
J Cachexia Sarcopenia Muscle ; 8(4): 598-606, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28474432

RESUMO

BACKGROUND: Ageing is associated with sarcopenia, osteoporosis, and increased fall risk, all of which contribute to increased fracture risk. Mechanically, bone strength adapts in response to forces created by muscle contractions. Adaptations can be through changes in bone size, geometry, and bending strength. Muscle mass is often used as a surrogate for muscle force; however, force can be increased without changes in muscle mass. Increased fall risk with ageing has been associated with a decline in muscle power-which is a measure of mobility. The aims of this study were as follows: (i) to investigate the relationship between muscle parameters in the upper and lower limbs with age in UK men and the influence of ethnicity on these relationships; (ii) to examine the relationships between jump force/grip strength/cross-sectional muscle area (CSMA) with bone outcomes at the radius and tibia. METHODS: White European, Black Afro-Caribbean, and South Asian men aged 40-79 years were recruited from Manchester, UK. Cortical bone mineral content, cross-sectional area, cortical area, cross-sectional moment of inertia, and CSMA were measured at the diaphysis of the radius and tibia using peripheral quantitative computed tomography. Lower limb jump force and power were measured from a single two-legged jump performed on a ground-reaction force platform. Grip strength was measured using a dynamometer. Associations between muscle and bone outcomes was determined using linear regression with adjustments for age, height, weight, and ethnicity. RESULTS: Three hundred and one men were recruited. Jump force was negatively associated with age; for every 10 year increase in age, there was a 4% reduction in jump force (P < 0.0001). There was a significant age-ethnicity interaction for jump power (P = 0.039); after adjustments, this was attenuated (P = 0.088). For every 10 year increase in age, grip strength decreased by 11%. Jump force was positively associated with tibial bone outcomes: a 1 standard deviation greater jump force was associated with significantly higher cortical bone mineral content 3.1%, cross-sectional area 4.2%, cortical area 3.4%, and cross-sectional moment of inertia 6.8% (all P < 0.001). Cross-sectional muscle area of the lower leg was not associated with tibial bone outcomes. Both grip strength and CSMA of the arm were positively associated, to a similar extent, with radius diaphyseal bone outcomes. CONCLUSIONS: Jump force and power are negatively associated with age in UK men. In the lower limb, the measurement of jump force is more strongly related to bone outcomes than CSMA. It is important to consider jump force and power when understanding the aetiology of bone loss and mobility in ageing men.


Assuntos
Osso e Ossos/anatomia & histologia , Força da Mão/fisiologia , Força Muscular/fisiologia , Músculos/anatomia & histologia , Adulto , Idoso , Anatomia Transversal , Densidade Óssea/fisiologia , Etnicidade , Exercício Físico/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Tíbia/anatomia & histologia , Reino Unido/epidemiologia
7.
Osteoporos Int ; 28(7): 2177-2186, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28365850

RESUMO

Bone health is critical for lower limb amputees, affecting their ability to use a prosthesis and their risk of osteoporosis. We found large losses in hip bone mineral density (BMD) and in amputated bone strength in the first year of prosthesis use, suggesting a need for load bearing interventions early post-amputation. INTRODUCTION: Large deficits in hip areal BMD (aBMD) and residual limb volumetric BMD (vBMD) occur after lower limb amputation; however, the time course of these bone quality changes is unknown. The purpose of this study was to quantify changes in the amputated bone that occur during the early stages post-amputation. METHODS: Eight traumatic unilateral amputees (23-53 years) were enrolled prior to surgery. Changes in total body, hip, and spine aBMD (dual-energy X-ray absorptiometry); in vBMD, stress-strain index (SSI), and muscle cross-sectional area (MCSA) (peripheral QCT); and in bone turnover markers were assessed after amputation prior to prosthesis fitting (pre-ambulatory) and at 6 and 12 months walking with prosthesis. RESULTS: Hip aBMD of the amputated limb decreased 11-15%, which persisted through 12 months. The amputated bone had decreases (p < 0.01) in BMC (-26%), vBMD (-21%), and SSI (-25%) from pre-ambulatory to 6 months on a prosthesis, which was maintained between 6 and 12 months. There was a decrease (p < 0.05) in the proportion of bone >650 mg/cm3 (58 to 43% of total area) or >480 mg/cm3 (65% to 53%), suggesting an increase in cortical porosity after amputation. Bone alkaline phosphatase and sclerostin were elevated (p < 0.05) at pre-ambulatory and then decreased towards baseline. Bone resorption markers were highest at surgery and pre-ambulatory and then progressively decreased (p < 0.05). CONCLUSIONS: Rapid and substantial losses in bone content and strength occur early after amputation and are not regained by 12 months of becoming ambulatory. Early post-amputation may be the most critical window for preventing bone loss.


Assuntos
Amputação Cirúrgica/efeitos adversos , Densidade Óssea/fisiologia , Extremidade Inferior/lesões , Osteoporose/etiologia , Absorciometria de Fóton , Adulto , Membros Artificiais , Feminino , Seguimentos , Humanos , Extremidade Inferior/cirurgia , Masculino , Pessoa de Meia-Idade , Osteoporose/fisiopatologia , Porosidade , Período Pós-Operatório , Tomografia Computadorizada por Raios X , Adulto Jovem
8.
Bone ; 99: 14-19, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28323146

RESUMO

INTRODUCTION: Both hypogonadism and type 2 diabetes mellitus (T2D) are associated with increased fracture risk. Emerging data support the negative effect of low testosterone on glucose metabolism, however, there is little information on the bone health of hypogonadal men with diabetes. We evaluated the bone mineral density (BMD), bone geometry and bone turnover of hypogonadal men with T2D compared to hypogonadal men without diabetes. MATERIALS AND METHODS: Cross-sectional study, men 40-74years old, with average morning testosterone (done twice) of<300ng/dl. Areal BMD (aBMD) was measured by DXA; volumetric BMD (vBMD) and bone geometry by peripheral-quantitative-computed-tomography; serum C-telopeptide (CTX), osteocalcin, sclerostin and sex hormone-binding globulin (SHBG) by ELISA, testosterone and 25-hydroxyvitamin D (25OHD) by automated immunoassay and estradiol by liquid-chromatography/mass-spectrometry. Groups were compared by ANOVA adjusted for covariates. RESULTS: One-hundred five men, 49 with and 56 without diabetes were enrolled. Adjusted vBMD at 38% tibia was higher in diabetic than non-diabetic men (857.3±69.0mg/cm3 vs. 828.7±96.7mg/cm3, p=0.02). Endosteal (43.9±5.8mm vs. 47.1±7.8mm, p=0.04) and periosteal (78.4±5.0mm vs. 81.3±6.5mm, p=0.02) circumferences and total area (491.0±61.0mm2 vs. 527.7±87.2mm2, p=0.02) at 38% tibia, were lower in diabetic men even after adjustments for covariates. CTX (0.25±0.14ng/ml vs. 0.40±0.19ng/ml, p<0.001) and osteocalcin (4.8±2.8ng/ml vs. 6.8±3.5ng/ml, p=0.006) were lower in diabetic men; there were no differences in sclerostin and 25OHD. Circulating gonadal hormones were comparable between the groups. CONCLUSION: Among hypogonadal men, those with T2D have higher BMD, poorer bone geometry and relatively suppressed bone turnover. Studies with larger sample size are needed to verify our findings and possible even greater risk for fractures among hypogonadal diabetic men.


Assuntos
Remodelação Óssea/fisiologia , Osso e Ossos/anatomia & histologia , Osso e Ossos/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Adulto , Idoso , Densidade Óssea/fisiologia , Colágeno Tipo I/sangue , Estudos Transversais , Humanos , Hipogonadismo/sangue , Hipogonadismo/metabolismo , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue , Peptídeos/sangue , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue , Vitamina D/análogos & derivados , Vitamina D/sangue
9.
Arch Osteoporos ; 12(1): 19, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28197890

RESUMO

In pre-pubertal girls, nutrient intakes and non-aquatic organized activity were evaluated as factors in vertebral body bone mass, structure, and strength. Activity, vitamin B12, and dietary fiber predicted bone outcomes most consistently. Exercise and vitamin B12 appear beneficial, whereas high fiber intake appears to be adverse for vertebral body development. PURPOSE: Childhood development sets the baseline for adult fracture risk. Most studies evaluate development using postero-anterior (PA) dual-energy X-ray absorptiometry (DXA) areal bone mineral density, bone mineral content, and bone mineral apparent density. In a prior analysis, we demonstrated that PA DXA reflects posterior element properties, rather than vertebral body fracture sites, such that loading is associated with subtle differences in vertebral body geometry, not 3D density. The current analysis is restricted to pre-pubertal girls, for a focused exploration of key nutrient intakes and physical activity as factors in dual plane indices of vertebral body geometry, density, and strength. METHODS: This cross-sectional analysis used paired PA and supine lateral (LAT) lumbar spine DXA scans to assess "3D" vertebral body bone mineral apparent density (PALATBMAD), "3D" index of structural strength in axial compression (PALATIBS), and fracture risk index (PALATFRI). Diet data were collected using the Youth/Adolescent Questionnaire (YAQ, 1995); organized physical activity was recorded via calendar-based form. Pearson correlations and backward stepwise multiple linear regression analyzed associations among key nutrients, physical activity, and bone outcomes. RESULTS: After accounting for activity and key covariates, fiber, unsupplemented vitamin B12, zinc, carbohydrate, vitamin C, unsupplemented magnesium, and unsupplemented calcium intake explained significant variance for one or more bone outcomes (p < 0.05). After adjustment for influential key nutrients and covariates, activity exposure was associated with postero-anterior (PA) areal bone mineral density, PA bone mineral content, PA width, lateral (LAT) BMC, "3D" bone cross-sectional area (coronal plane), "3D" PALATIBS, and PALATFRI benefits (p < 0.05). CONCLUSIONS: Physical activity, fiber intake, and unsupplemented B12 intake appear to influence vertebral body bone mass, density, geometry, and strength in well-nourished pre-pubertal girls; high fiber intakes may adversely affect childhood vertebral body growth.


Assuntos
Densidade Óssea/fisiologia , Desenvolvimento Infantil/fisiologia , Fibras na Dieta/metabolismo , Exercício Físico/fisiologia , Coluna Vertebral , Vitamina B 12/metabolismo , Absorciometria de Fóton/métodos , Adolescente , Adrenarca/fisiologia , Criança , Estudos Transversais , Dieta , Fibras na Dieta/efeitos adversos , Feminino , Humanos , Modelos Lineares , Avaliação Nutricional , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/crescimento & desenvolvimento
10.
Osteoporos Int ; 28(4): 1365-1376, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28032184

RESUMO

Many female athletes are energy and/or estrogen deficient, but the independent effects on bone health have not been isolated. Energy deficiency was detrimental at the tibia while estrogen deficiency was detrimental at the radius. Nutrition must be considered alongside menstrual recovery when addressing compromised bone health in female athletes. INTRODUCTION: The purpose of this study was to describe volumetric bone mineral density (vBMD), bone geometry, and estimated bone strength in exercising women (n = 60) grouped according to energy status (energy replete (EnR: n = 30) vs. energy deficient (EnD: n = 30)) and estrogen status (estrogen replete (E2R: n = 33) vs. estrogen deficient (E2D: n = 27)), resulting in four distinct groups: EnR + E2R (n = 17), EnR + E2D (n = 13), EnD + E2R (n = 16), EnD + E2D (n = 14). METHODS: Energy status was determined using the ratio of measured to predicted resting energy expenditure (mREE/pREE). Estrogen status was based on self-reported menstrual status confirmed by daily evaluation of urinary estrone-1-glucoronide (E1G), pregnanediol glucuronide (PdG), and luteinizing hormone (LH). Eumenorrheic women were considered E2R, amenorrheic women were E2D, and oligomenorrheic women were categorized based on history of menses in the past year. Bone was assessed using peripheral quantitative computed tomography (pQCT). RESULTS: EnD women exhibited lower total vBMD, trabecular vBMD, cortical area, and BSI at the distal tibia and lower total vBMD, smaller cortical area and cortical thickness, and larger endosteal circumference at the proximal tibia compared to EnR women (p < 0.042). E2D women had lower total and cortical vBMD, larger total and trabecular area, and lower BSI at the distal radius and lower cortical vBMD at the proximal radius compared to E2R women (p < 0.023). Energy and estrogen interacted to affect total and trabecular area at the distal tibia (p < 0.021). CONCLUSIONS: Efforts to correct energy deficiency, which in turn may promote reproductive health, are warranted in order to address the unique contributions of energy status versus estrogen status to bone health.


Assuntos
Densidade Óssea/fisiologia , Metabolismo Energético/fisiologia , Estrogênios/deficiência , Exercício Físico/fisiologia , Adolescente , Adulto , Antropometria/métodos , Estudos Transversais , Feminino , Humanos , Ciclo Menstrual/fisiologia , Rádio (Anatomia)/fisiologia , Tíbia/fisiologia , Tomografia Computadorizada por Raios X , Adulto Jovem
11.
Bone ; 83: 104-110, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-26518742

RESUMO

Subclinical hyperthyroidism has been reported to increase the fracture risk. However, the effect of thyroid stimulating hormone (TSH) suppressive therapy on bone geometry in the hip area of patients with differentiated thyroid carcinoma (DTC) is still unclear. The aim of this study was to investigate the effect of TSH suppression on bone geometry in the hip area of pre- and postmenopausal women with DTC. We conducted a retrospective cohort study including 99 women with DTC (25 pre- and 74 postmenopausal) who had received TSH suppressive therapy for at least 3years and 297 control subjects (75 and 222, respectively) matched for sex and age. Bone mineral density (BMD) in the spine and hip area and bone geometry at the femoral neck measured by dual energy X-ray absorptiometry (DXA) were compared between patients and controls. The association between thyroid hormone and bone parameters was investigated. All analyses of bone parameters were adjusted for age, body mass index, and serum calcium levels. In premenopausal subjects, TSH suppressive therapy was not associated with poor bone parameters. In postmenopausal subjects, patients with DTC undergoing TSH suppression showed lower cross-sectional moment of inertia (CSMI), cross-sectional area, and section modulus and thinner cortical thickness at the femoral neck than those of control subjects, whereas their femoral neck BMD was comparable with controls. Total hip BMD was lower in postmenopausal patients than in controls. CSMI and section modulus at the femoral neck were independently associated with serum free T4 levels in postmenopausal patients. The difference in femoral neck bone geometry between patients and controls was only apparent in postmenopausal DTC patients with free T4 >1.79ng/dL (23.04pmol/l), and not in those with free T4 levels ≤1.79ng/dL (23.04pmol/l). TSH suppression in postmenopausal DTC patients was associated with decreased bone strength by altering bone geometry rather than BMD in the hip area, especially the femoral neck. This alteration in bone quality was observed only in patients with free T4 levels above the upper normal limit.


Assuntos
Quadril/patologia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Tireotropina/uso terapêutico , Estudos de Casos e Controles , Feminino , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias da Glândula Tireoide/sangue , Tiroxina/sangue
12.
Calcif Tissue Int ; 97(6): 551-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26232103

RESUMO

Aromatase inhibitors (AIs), the standard therapy for estrogen receptor- or progesterone receptor-positive breast cancer in postmenopausal women, lead to increased hip fractures in breast cancer patients. To investigate the mechanism of increased incidence of hip fractures in breast cancer patients treated with AIs, we evaluated bone mineral density (BMD) in the cortical and trabecular compartments and assessed femoral geometry using quantitative computed tomography (QCT) in breast cancer patients. In total, 249 early breast cancer patients who underwent QCT in their fifties (mean age 54.3 years) were retrospectively analyzed. Proximal femoral BMD and geometrical parameters were compared. In all regions of the proximal femur, cortical areal BMDs were lower in the AI group than in the non-AI group (p < 0.05). Cortical thickness of the femoral neck, trochanter, and total hip was significantly lower in the AI group compared with the non-AI group (p < 0.05). Analysis of the narrowest section of the femoral neck showed significantly thinner cortical bone and smaller cortical area in the AI group than in the non-AI group (p < 0.05), especially in the superoposterior quadrant. Bone strength parameters in the femoral neck, such as the section modulus and cross-sectional moment of inertia, were significantly lower in the AI group than in the non-AI group (p < 0.05). In conclusion, AI treatment in breast cancer patients is associated with deterioration of femoral cortical BMD and geometry, which could contribute in site-specific weakened bone strength and increased incidence of hip fractures.


Assuntos
Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Colo do Fêmur/efeitos dos fármacos , Colo do Fêmur/diagnóstico por imagem , Densidade Óssea/efeitos dos fármacos , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Tomografia Computadorizada por Raios X
13.
Bone ; 78: 122-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25959415

RESUMO

PURPOSE: Chronic heavy alcohol consumption is associated with bone density loss and increased fracture risk, while low levels of alcohol consumption have been reported as beneficial in some studies. However, studies relating alcohol consumption to bone geometry, volumetric bone mineral density (vBMD) and bone microarchitecture, as assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT), are lacking. METHODS: Here we report an analysis from the Hertfordshire Cohort Study, in which we studied associations between HR-pQCT measures at the distal radius and tibia and alcohol consumption in 376 participants (198 men and 178 women) aged 72.1-81.4 years. RESULTS: A total of 30 (15.2%), 90 (45.5%) and 78 (39.4%) men drank minimal/none (<1 unit/week), low (≥1 unit/week and <11 units/week) and moderate/high (≥11 units/week) amounts of alcohol respectively. These figures were 74 (41.8%), 80 (45.2%) and 23 (13.0%) respectively in women for minimal/none (<1 unit/week), low (≥1 unit/week and <8 units/week) and moderate/high (≥8 units/week). At the distal radius, after adjustment for confounding factors (age, BMI, smoking status, dietary calcium intake, physical activity and socioeconomic status and years since menopause and HRT use for women), men that drank low alcohol had lower cortical thickness (p=0.038), cortical vBMD (p=0.033), and trabecular vBMD (p=0.028) and higher trabecular separation (p=0.043) than those that drank none/minimal alcohol. Similar differences were shown between minimal/none and moderate/high alcohol although these only reached statistical significance for the cortical parameters. Interestingly, after similar adjustment, women showed similar differences in the trabecular compartment between none/minimal alcohol and low alcohol at the distal tibia. However, women that drank moderate/high alcohol had significantly higher trabecular vBMD (p=0.007), trabecular thickness (p=0.026), and trabecular number (p=0.042) and higher trabecular separation (p=0.026) at the distal radius than those that drank low alcohol. CONCLUSIONS: Our results suggest that alcohol consumption (low and moderate/high) may have a detrimental impact on bone health in men in both the cortical and trabecular compartments at the distal radius with similar results in women in the trabecular compartment between none/minimal alcohol and low alcohol at the distal tibia suggesting that avoidance of alcohol may be beneficial for bone health.


Assuntos
Consumo de Bebidas Alcoólicas , Rádio (Anatomia)/patologia , Tíbia/patologia , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Estudos de Coortes , Feminino , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/patologia , Humanos , Masculino , Rádio (Anatomia)/diagnóstico por imagem , Análise de Regressão , Tíbia/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Reino Unido
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