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1.
Osteoporos Int ; 25(8): 2027-33, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24803329

RESUMO

UNLABELLED: In this longitudinal case-control study, acute fracture was associated with low serum testosterone, which was transient in 43% of men. While assessment of gonadal status is part of the assessment of bone fragility, measurement of testosterone in the early period after fracture may overestimate the prevalence of androgen deficiency. INTRODUCTION: Measurement of circulating testosterone is recommended in the evaluation of bone fragility in men. Since acute illness can transiently decrease circulating testosterone, we quantified the association of acute fracture and serum testosterone levels. METHODS: A case-control study was conducted involving 240 men with a radiologically confirmed minimal trauma fracture presenting to a tertiary referral hospital and 89 age-matched men without a history of minimal trauma fracture serving as controls. Follow-up testosterone levels 6 months after baseline were available for 98 cases and 27 controls. Results were expressed as the median and interquartile (IQR) range. RESULTS: Compared to controls, cases had lower total testosterone [TT, 7.2 (3.5, 10.8) vs 13.6 (10.9, 17.1) nmol/L, p < 0.001]. The 143 cases treated as inpatients had lower testosterone levels than the 97 cases treated as outpatients [TT 4.7 (2.3, 8.1) vs 10.3 (7.5, 12.7) nmol/L, p < 0.001]. Group differences in calculated free testosterone (cFT) were comparable to the group differences in TT. At follow-up, in 98 cases, median TT increased from 6.5 nmol/L (3.2, 8.5) to 9.6 nmol/L (6.9, 12.0) p < 0.0001, and SHBG remained unchanged. Of cases with low testosterone, 43% with TT <10 nmol/L and/or cFT <230 pmol/L at presentation were reclassified as androgen sufficient at follow-up. TT was unchanged in the controls. CONCLUSIONS: Low testosterone levels in men presenting with an acute fracture may, at least in part, be due to an acute, fracture-associated, stress response. To avoid over diagnosis, evaluation for testosterone deficiency should be deferred until recovery from the acute event.


Assuntos
Fraturas por Osteoporose/sangue , Testosterona/sangue , Absorciometria de Fóton/métodos , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Estudos de Casos e Controles , Comorbidade , Seguimentos , Articulação do Quadril/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/fisiopatologia , Testosterona/deficiência
2.
Osteoporos Int ; 23(10): 2461-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22215183

RESUMO

UNLABELLED: Sunlight deprivation results in vitamin D deficiency but serum vitamin D levels can be maintained above 50 nmol/L when supplemented with 50,000 IU at least every alternate month. INTRODUCTION: Antarctic expeditioners are exposed to prolonged sunlight deprivation resulting in vitamin D deficiency. We hypothesised that monthly dosing of 50,000 IU vitamin D (~1,600 IU daily) will increase serum 25-hydroxyvitamin D (25(OH)D), suppress parathyroid hormone (PTH) and improve bone mineral density (BMD), 50,000 IU alternate months (~800 IU daily) will maintain these measures, while a single 50,000 IU dose pre-departure (~1,00 IU daily) will not be protective. METHODS: This was a randomised double-blind study involving 110 healthy adults: 91 males, mean age 41 years (range 24-65 years) working in Antarctica for up to 12 months, who we administered 50,000 IU vitamin D3 monthly, alternate months or a single dose pre-departure. Serum 25(OH)D, PTH, osteocalcin, CTx and calcium were assessed at baseline, mid- and end of expedition. Proximal femur and lumbar spine BMD were assessed pre- and post-expedition. RESULTS: Baseline 25(OH)D was 59 ± 14 nmol/L. By mid-expedition, 25(OH)D increased by 7 nmol/L in those supplemented monthly (p < 0.05) and remained unchanged in those supplemented in alternate months. In those given a single dose pre-departure, 25(OH)D decreased by 8 nmol/L (p < 0.05) and PTH increased by 27% (p < 0.09). Serum osteocalcin increased by ~22% in all groups but BMD remained unchanged. If serum 25(OH)D was >50 nmol/L at baseline, 25(OH)D was maintained above this level with all regimens. If 25(OH)D was <50 nmol/L at baseline, monthly or alternate month regimens were needed to achieve levels >50 nmol/L, the single pre-departure dose was ineffective. CONCLUSION: During sunlight deprivation of up to 12 months, serum 25(OH)D levels can be maintained above 50 nmol/L when expeditioners are provided with 50,000 I U at least every alternate month.


Assuntos
Suplementos Nutricionais , Expedições , Deficiência de Vitamina D/prevenção & controle , Vitamina D/uso terapêutico , Adulto , Idoso , Regiões Antárticas , Cálcio/sangue , Método Duplo-Cego , Esquema de Medicação , Feminino , Fêmur/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue , Hormônio Paratireóideo/sangue , Luz Solar , Vitamina D/administração & dosagem , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/fisiopatologia , Adulto Jovem
3.
Osteoporos Int ; 20(9): 1523-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19151911

RESUMO

UNLABELLED: Serum 25(OH)D levels decline without sunlight exposure. We studied 120 expeditioners to Antarctica to determine the skeletal and hormonal responses to sunlight deprivation. With emerging vitamin D insufficiency, serum calcium decreased, PTH increased, and bone loss at the proximal femur was observed. Baseline serum 25(OH)D levels >100 nmol/L prevented vitamin D insufficiency. INTRODUCTION: Vitamin D stores deplete without adequate sunlight exposure unless supplementation is provided. We studied 120 healthy adults who spent a year in Antarctica as a model for sunlight deprivation to define the timing and magnitude of the skeletal and hormonal responses to emerging vitamin D insufficiency. METHODS: Fasting blood samples were assessed at baseline, 6 and 12 months for serum 25-hydroxyvitamin D (25(OH)D), osteocalcin (OC), bone formation (P1NP) and resorption (CTx), PTH and calcium. Lumbar spine and proximal femur BMD was measured using DXA. Differences over time were determined using repeated measures ANOVA. Percent changes were expressed as (Delta value/(value A + value B)/2) x 100. Relationships between outcome measures were determined using Spearman's correlations. RESULTS: Vitamin D insufficiency (<50 nmol/L) was observed in 85% of expeditioners by 6 months when serum calcium decreased and PTH increased (p < 0.01). By 12 months, OC increased by 7.4 +/- 3.0% (p < 0.05), and BMD decreased by 1.0 +/- 2.0% at the total proximal femur (p < 0.05). For those with vitamin D sufficiency at baseline (>50 nmol/L), sunlight deprivation produced vitamin D insufficiency within 4 months unless baseline values were >100 nmol/L. CONCLUSION: Supplementation may be necessary for expeditioners with limited access to UV light.


Assuntos
Osso e Ossos/metabolismo , Osteocalcina/sangue , Luz Solar , Deficiência de Vitamina D/sangue , Vitamina D/análogos & derivados , Vitamina D/sangue , Adulto , Análise de Variância , Regiões Antárticas/epidemiologia , Biomarcadores/sangue , Reabsorção Óssea/epidemiologia , Reabsorção Óssea/etiologia , Suplementos Nutricionais , Jejum/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Estudos Prospectivos , Vitamina D/biossíntese , Deficiência de Vitamina D/complicações , Adulto Jovem
4.
J Nutr Health Aging ; 13(8): 693-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19657552

RESUMO

BACKGROUND: Most studies reporting malnutrition in the elderly relate to high-level care. However, one third of Australians in aged care reside in low-level care facilities. Data is limited on their nutritional status. OBJECTIVE: To investigate the nutritional status of elderly in low-level care facilities. DESIGN: A cross sectional study design. SETTING: 14 low-level aged care facilities in metropolitan Melbourne. PARTICIPANTS: Convenience sample of 103 ambulatory elderly (86 +/- 6.6 years (mean +/- SD), 76% female, comprising 15% of the hostel population) able to perform daily functions of living. MEASUREMENTS: Nutritional intake assessed by three-day weighed food records, and nutritional status by haematological and biochemical markers and body composition (dual energy X-ray absorptiometry). RESULTS: FOOD served did not supply the estimated average requirements (EAR) for 5 of the 14 nutrients analysed. Compared with EAR, 34% of participants were protein malnourished and 62% had energy intake deficits. Micronutrient intake was low for calcium, magnesium, folate, zinc (for men) and dietary fibre. Vitamin D deficiency (serum 25OH Vitamin D < 50 nmol/L) was present in 58% of residents. More men than women had low haemoglobin (P < 0.000), low red blood cells (P < 0.000), and a raised white blood cell count (P = 0.004). Forty three percent of men and 21% women had sarcopenia, 28% of men and 44% women had excess body fat (> 28% and >40%, respectively) and 14% of men and 12 % of women were sarcopenic-obese. Only 12% showed no sign of undernutrition using seven different nutritional indicators. Around 65% had two or more indicators of undernutrition. CONCLUSION: These findings highlight the need for the supply of more, better quality, nutrient dense food to residents and better detection of undernutrition in aged care facilities. Maintenance of nutritional status has the potential to reduce morbidity and delay the transition to high-level care.


Assuntos
Anemia/epidemiologia , Deficiências Nutricionais/epidemiologia , Estado Nutricional , Obesidade/epidemiologia , Desnutrição Proteico-Calórica/epidemiologia , Sarcopenia/epidemiologia , Atividades Cotidianas , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Contagem de Células Sanguíneas , Estudos Transversais , Dieta/normas , Ingestão de Energia , Feminino , Humanos , Institucionalização , Masculino , Micronutrientes/administração & dosagem , Necessidades Nutricionais , Fatores Sexuais , Deficiência de Vitamina D/epidemiologia
5.
Osteoporos Int ; 17(12): 1794-800, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17019522

RESUMO

INTRODUCTION AND HYPOTHESIS: Calcium supplementation enhances bone mass accrual during administration, with a sustained benefit observed using milk-based calcium but not calcium salts. We tested the hypothesis that calcium from milk minerals but not calcium carbonate will be sustained after supplementation was discontinued. METHODS: Ninety-nine pre-pubertal boys and girls aged 5-11 years were followed for 12 months after being randomized to receive 800 mg/day of calcium from milk minerals (MM) or calcium carbonate (CC), or a placebo (Pla) in a 10-month double blind study. Total body and regional BMC, and femoral shaft bone dimensions were measured using dual energy x-ray absorptiometry. Group differences were determined using ANCOVA. RESULTS: In the intention to treat analysis of the entire sample, no group differences were observed in increments in BMC or bone dimensions during or after supplementation. In those children who remained pre-pubertal, greater gains in pelvis BMC in the milk mineral group than controls were sustained (37.9 versus 29.3% respectively, p<0.02). CONCLUSION: In healthy children consuming about 800 mg calcium daily, calcium supplementation with milk minerals or calcium carbonate does not appear to be produce biologically meaningful benefits to skeletal health. A benefit of calcium supplementation in pre-pubertal was evident, but inconclusive, with the biological significance of the effect of calcium supplementation at the pelvis, and the longevity of this effect to be determined.


Assuntos
Desenvolvimento Ósseo/fisiologia , Cálcio da Dieta/administração & dosagem , Animais , Densidade Óssea/fisiologia , Carbonato de Cálcio/química , Criança , Desenvolvimento Infantil/fisiologia , Pré-Escolar , Método Duplo-Cego , Feminino , Fêmur/crescimento & desenvolvimento , Humanos , Masculino , Leite/química , Ossos Pélvicos/crescimento & desenvolvimento
6.
Am J Hum Biol ; 13(1): 1-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11466961

RESUMO

Height, weight, and tissue accrual were determined in 60 male and 53 female adolescents measured annually over six years using standard anthropometry and dual-energy X-ray absorptiometry (DXA). Annual velocities were derived, and the ages and magnitudes of peak height and peak tissue velocities were determined using a cubic spline fit to individual data. Individuals were rank ordered on the basis of sex and age at peak height velocity (PHV) and then divided into quartiles: early (lowest quartile), average (middle two quartiles), and late (highest quartile) maturers. Sex- and maturity-related comparisons in ages and magnitudes of peak height and peak tissue velocities were made. Males reached peak velocities significantly later than females for all tissues and had significantly greater magnitudes at peak. The age at PHV was negatively correlated with the magnitude of PHV in both sexes. At a similar maturity point (age at PHV) there were no differences in weight or fat mass among maturity groups in both sexes. Late maturing males, however, accrued more bone mineral and lean mass and were taller at the age of PHV compared to early maturers. Thus, maturational status (early, average, or late maturity) as indicated by age at PHV is inversely related to the magnitude of PHV in both sexes. At a similar maturational point there are no differences between early and late maturers for weight and fat mass in boys and girls.


Assuntos
Composição Corporal/fisiologia , Constituição Corporal/fisiologia , Estatura/fisiologia , Peso Corporal/fisiologia , Puberdade/fisiologia , Adolescente , Análise de Variância , Criança , Exercício Físico/fisiologia , Feminino , Humanos , Estilo de Vida , Estudos Longitudinais , Masculino , Estado Nutricional , Saskatchewan , Caracteres Sexuais , Fatores de Tempo
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