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1.
Arch Intern Med ; 168(1): 103-8, 2008 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-18195202

RESUMEN

BACKGROUND: Ergocalciferol (vitamin D(2)) supplementation plays a role in fall prevention, but the effect in patients living in the community in sunny climates remains uncertain. We evaluated the effect of ergocalciferol and calcium citrate supplementation compared with calcium alone on the risk of falls in older women at high risk of falling. METHODS: A 1-year population-based, double-blind, randomized controlled trial of 302 community-dwelling ambulant older women aged 70 to 90 years living in Perth, Australia (latitude, 32 degrees S), with a serum 25-hydroxyvitamin D concentration of less than 24.0 ng/mL and a history of falling in the previous year. Participants were randomized to receive ergocalciferol, 1000 IU/d, or identical placebo (hereinafter, ergocalciferol and control groups, respectively). Both groups received calcium citrate, 1000 mg/d. Fall data were collected every 6 weeks. RESULTS: Ergocalciferol therapy reduced the risk of having at least 1 fall over 1 year after adjustment for baseline height, which was significantly different between the 2 groups (ergocalciferol group, 53.0%; control group, 62.9%; odds ratio [OR], 0.61; 95% confidence interval [CI], 0.37-0.99). When those who fell were grouped by the season of first fall or the number of falls they had, ergocalciferol treatment reduced the risk of having the first fall in winter and spring (ergocalciferol group, 25.2%; control group, 35.8%; OR, 0.55; 95% CI, 0.32-0.96) but not in summer and autumn, and reduced the risk of having 1 fall (ergocalciferol group, 21.2%; control group, 33.8%; OR, 0.50; 95% CI, 0.28-0.88) but not multiple falls. CONCLUSION: Patients with a history of falling and vitamin D insufficiency living in sunny climates benefit from ergocalciferol supplementation in addition to calcium, which is associated with a 19% reduction in the relative risk of falling, mostly in winter.


Asunto(s)
Accidentes por Caídas/prevención & control , Conservadores de la Densidad Ósea/administración & dosificación , Citrato de Calcio/administración & dosificación , Ergocalciferoles/administración & dosificación , Anciano , Anciano de 80 o más Años , Suplementos Dietéticos , Método Doble Ciego , Femenino , Humanos , Resultado del Tratamiento , Deficiencia de Vitamina D/tratamiento farmacológico
2.
Am J Clin Nutr ; 87(1): 175-80, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18175753

RESUMEN

BACKGROUND: Nutrition is important for the development and maintenance of bone structure and for the prevention of osteoporosis and fracture. The relation of chocolate intake with bone has yet to be investigated. OBJECTIVE: We investigated the relation of chocolate consumption with measurements of whole-body and regional bone density and strength. DESIGN: Randomly selected women aged 70-85 y (n=1460) were recruited from the general population to a randomized controlled trial of calcium supplementation and fracture risk. We present here a cross-sectional analysis of 1001 of these women. Bone density and strength were measured with the use of dual-energy X-ray absorptiometry, peripheral quantitative computed tomography, and quantitative ultrasonography. Frequency of chocolate intake was assessed with the use of a questionnaire and condensed into 3 categories: <1 time/wk, 1-6 times/wk, >or=1 time/d. RESULTS: Higher frequency of chocolate consumption was linearly related to lower bone density and strength (P<0.05). Daily (>or=1 times/d) consumption of chocolate, in comparison to <1 time/wk, was associated with a 3.1% lower whole-body bone density; with similarly lower bone density of the total hip, femoral neck, tibia, and heel; and with lower bone strength in the tibia and the heel (P<0.05, for all). Adjustment for covariates did not influence interpretation of the results. CONCLUSIONS: Older women who consume chocolate daily had lower bone density and strength. Additional cross-sectional and longitudinal studies are needed to confirm these observations. Confirmation of these findings could have important implications for prevention of osteoporotic fracture.


Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Densidad Ósea/efectos de los fármacos , Cacao , Calcio de la Dieta/administración & dosificación , Dulces , Osteoporosis Posmenopáusica/prevención & control , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Densidad Ósea/fisiología , Cacao/efectos adversos , Dulces/efectos adversos , Estudios Transversales , Suplementos Dietéticos , Femenino , Humanos , Modelos Lineales , Estudios Prospectivos , Factores de Riesgo , Encuestas y Cuestionarios
3.
J Clin Endocrinol Metab ; 93(3): 743-9, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18089701

RESUMEN

CONTEXT: Effects of long-term calcium, with or without vitamin D, on hip bone mineral density (BMD) and bone turnover in sunny climates have not been reported. OBJECTIVE: The aim was to evaluate the effect of vitamin D added to calcium supplementation on hip dual-energy x-ray absorptiometry BMD and calcium-related analytes. DESIGN, SETTING, AND PARTICIPANTS: The study was a 5-yr randomized, controlled, double-blind trial of 120 community-dwelling women aged 70-80 yr. INTERVENTIONS: The interventions were 1200 mg/d calcium with placebo vitamin D (Ca group) or with 1000 IU/d vitamin D2 (CaD group), or double placebo (control). MAIN OUTCOME MEASURES: Hip BMD, plasma 25-hydroxyvitamin D, biomarkers of bone turnover, PTH, and intestinal calcium absorption were measured. RESULTS: Hip BMD was preserved in CaD (-0.17%) and Ca (0.19%) groups but not controls (-1.27%) at yr 1 and maintained in the CaD group only at yr 3 and 5. The beneficial effects were mainly in those with baseline 25-hydroxyvitamin D levels below the median (68 nmol/liter). At yr 1, compared with controls, the Ca and CaD groups had 6.8 and 11.3% lower plasma alkaline phosphatase, respectively (P

Asunto(s)
Calcio/administración & dosificación , Suplementos Dietéticos , Vitamina D/administración & dosificación , Anciano , Anciano de 80 o más Años , Atención Ambulatoria , Densidad Ósea , Calcio/metabolismo , Método Doble Ciego , Femenino , Humanos , Absorción Intestinal , Hormona Paratiroidea/sangre , Cooperación del Paciente , Vitamina D/análogos & derivados , Vitamina D/sangre
4.
Am J Clin Nutr ; 86(4): 1243-7, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17921409

RESUMEN

BACKGROUND: Impaired hip structure assessed by dual-energy X-ray absorptiometry (DXA) areal bone mineral density (aBMD) is an independent predictor for osteoporotic hip fracture. Some studies suggest that tea intake may protect against bone loss. OBJECTIVE: Using both cross-sectional and longitudinal study designs, we examined the relation of tea consumption with hip structure. DESIGN: Randomly selected women (n = 1500) aged 70-85 y participated in a 5-y prospective trial to evaluate whether oral calcium supplements prevent osteoporotic fractures. aBMD at the hip was measured at years 1 and 5 with DXA. A cross-sectional analysis of 1027 of these women at 5 y assessed the relation of usual tea intake, measured by using a questionnaire, with aBMD. A prospective analysis of 164 women assessed the relation of tea intake at baseline, measured by using a 24-h dietary recall, with change in aBMD from years 1 to 5. RESULTS: In the cross-sectional analysis, total hip aBMD was 2.8% greater in tea drinkers (x: 806; 95% CI: 797, 815 mg/cm(2)) than in non-tea drinkers (784; 764, 803 mg/cm(2)) (P < 0.05). In the prospective analysis over 4 y, tea drinkers lost an average of 1.6% of their total hip aBMD (-32; -45, -19 mg/cm(2)), but non-tea drinkers lost 4.0% (-13; -20, -5 mg/cm(2)) (P < 0.05). Adjustment for covariates did not influence the interpretation of results. CONCLUSION: Tea drinking is associated with preservation of hip structure in elderly women. This finding provides further evidence of the beneficial effects of tea consumption on the skeleton.


Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Densidad Ósea/efectos de los fármacos , Calcio de la Dieta/administración & dosificación , Fracturas de Cadera/prevención & control , Osteoporosis Posmenopáusica/prevención & control , , Absorciometría de Fotón/métodos , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Bebidas , Densidad Ósea/fisiología , Estudios Transversales , Femenino , Fracturas de Cadera/diagnóstico por imagen , Fracturas de Cadera/epidemiología , Humanos , Estudios Longitudinales , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/diagnóstico por imagen , Osteoporosis Posmenopáusica/epidemiología , Estudios Prospectivos , Encuestas y Cuestionarios , Té/química
5.
Arch Intern Med ; 166(8): 869-75, 2006 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-16636212

RESUMEN

BACKGROUND: Increased dietary calcium intake has been proposed as a population-based public health intervention to prevent osteoporotic fractures. We have examined whether calcium supplementation decreases clinical fracture risk in elderly women and its mechanism of action. METHODS: Five-year, double-blind, placebo-controlled study of 1460 women recruited from the population and older than 70 years (mean age, 75 years) who were randomized to receive calcium carbonate, 600 mg twice per day, or identical placebo. The primary end points included clinical incident osteoporotic fractures, vertebral deformity, and adverse events ascertained in 5 years. Bone structure was also measured using dual x-ray absorptiometry of the hip and whole body, quantitative ultrasonography of the heel, and peripheral quantitative computed tomography of the distal radius. RESULTS: Among our patients, 16.1% sustained 1 or more clinical osteoporotic fractures. In the intention-to-treat analysis, calcium supplementation did not significantly reduce fracture risk (hazard ratio, 0.87; 95% confidence interval, 0.67-1.12). However, 830 patients (56.8%) who took 80% or more of their tablets (calcium or placebo) per year had reduced fracture incidence in the calcium compared with the placebo groups (10.2% vs 15.4%; hazard ratio, 0.66; 95% confidence interval, 0.45-0.97). Calcium-treated patients had improved quantitative ultrasonography findings of the heel, femoral neck and whole-body dual x-ray absorptiometry data, and bone strength compared with placebo-treated patients. Of the 92 000 adverse events recorded, constipation was the only event increased by the treatment (calcium group, 13.4%; placebo group, 9.1%). CONCLUSION: Supplementation with calcium carbonate tablets supplying 1200 mg/d is ineffective as a public health intervention in preventing clinical fractures in the ambulatory elderly population owing to poor long-term compliance, but it is effective in those patients who are compliant.


Asunto(s)
Carbonato de Calcio/uso terapéutico , Suplementos Dietéticos , Fracturas Óseas/prevención & control , Absorciometría de Fotón , Anciano , Densidad Ósea , Carbonato de Calcio/administración & dosificación , Método Doble Ciego , Femenino , Cuello Femoral/diagnóstico por imagen , Estudios de Seguimiento , Fracturas Óseas/diagnóstico , Fracturas Óseas/epidemiología , Talón/diagnóstico por imagen , Humanos , Incidencia , Persona de Mediana Edad , Osteoporosis/diagnóstico por imagen , Osteoporosis/prevención & control , Pacientes Ambulatorios , Radio (Anatomía)/diagnóstico por imagen , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Ultrasonografía , Australia Occidental/epidemiología
6.
Am J Chin Med ; 31(1): 87-101, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12723758

RESUMEN

For many decades, the Chinese have been using herbal medications to treat bone diseases. To examine effects of an extract of ten medicinal herbs on estrogen deficiency bone loss, ten-month-old female rats were randomly divided into three groups: ovariectomized (OVX), OVX treated with herbs (OVX-M) 4 ml/day by gavage, and OVX treated with estrogen (OVX-E) 10 mg subcutaneously (s.c.) twice per week. The bone mineral density (BMD) of the left femur (fBMD), spine (sBMD) and global body (gBMD) were measured at baseline and at 4, 8 and 12 weeks using a Hologic QDR 2000 dual-energy X-ray densitometer. Tibial strength was tested using the Instron Model 5566 electro-mechanical testing machine. The urinary pyridinoline creatinine ratio (Pyd/Cr), deoxypyridinoline creatinine ratio (Dpd/Cr), plasma alkaline phosphatase (ALP), calcium (CA), phosphorus (P) and albumin (ALB) were also determined. Uterine weight was determined at 12 weeks. The results showed that percent changes of fBMD in the OVX (n = 9), OVX-E (n = 8) and OVX-M (n = 8) rats at the 12-week time point were -11.8 +/- 4.6(c), 1.8 +/- 3.1(a), -7.6 +/- 1.9(abc) (p < 0.05-0.001, a: vs. OVX, b: vs. OVX-E, c: vs. baseline); sBMD were -10.7 +/- 4.6(c), -0.3 +/- 5.5(a), -5.9 +/- 3.5(abc); and gBMD were -4.8 +/- 2.3(c), 0.1 +/- 2.4(a), -2.7 +/- 2.6(abc), respectively. Further, the tibia maximum breaking stress and flexural modulus of elasticity in OVX-M rats (295 +/- 33(a), 18,194 +/- 3,264(a)) were significantly higher (p < 0.005-0.001) than that in OVX rats (189 +/- 83, 10,309 +/- 4,930), and similar to OVX-E rats (298 +/- 35(a), 18,766 +/- 2,620(a)). Additionally, the herbal extract reduced the urinary Pyd/Cr, Dpd/Cr and plasma ALP increment followed OVX and was not associated with a rise in uterine weight. In conclusion, the herbal extract demonstrated a therapeutic effect to inhibit bone resorption and to reduce estrogen-dependent bone loss without uterine stimulation. It may have potential as a new approach in treating and preventing postmenopausal osteoporosis (PMOP).


Asunto(s)
Densidad Ósea/efectos de los fármacos , Remodelación Ósea/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Fosfatasa Alcalina/sangre , Aminoácidos/orina , Animales , Biomarcadores/orina , Creatinina/orina , Estrógenos/farmacología , Femenino , Fémur/fisiología , Tamaño de los Órganos , Ovariectomía , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Columna Vertebral/fisiología , Tibia/fisiología , Útero/anatomía & histología
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