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INTRODUCTION: Oxidative stress induced by reactive oxygen species (ROS) is associated with the risk of osteoporosis, and can be reduced by certain dietary antioxidants. Lycopene is an antioxidant known to decrease the risk of age-related chronic diseases, such as cancer. However, the role of lycopene in osteoporosis has not yet been investigated. MATERIALS AND METHODS: In a cross-sectional study, 33 postmenopausal women aged 50-60 years provided seven-day dietary records and blood samples. Serum samples were used to measure serum lycopene, lipid peroxidation, protein thiols, bone alkaline phosphatase (BAP), and cross-linked N-telopeptides of type I collagen (NTx). The serum lycopene per kilogram body weight of the participants was grouped into quartiles and associated with the above serum parameters using one-way ANOVA and the Newman-Keuls post-test. RESULTS: The results showed that groups with higher lycopene intake, as determined from the dietary records, had higher serum lycopene (p<0.02). A higher serum lycopene was found to be associated with a low NTx (p<0.005). Similarly, groups with higher serum lycopene had lower protein oxidation (p<0.05). DISCUSSION: In conclusion, these results suggest that the dietary antioxidant lycopene reduces oxidative stress and the levels of bone turnover markers in postmenopausal women, and may be beneficial in reducing the risk of osteoporosis.
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Antioxidantes/administración & dosificación , Resorción Ósea/prevención & control , Carotenoides/administración & dosificación , Estrés Oxidativo/efectos de los fármacos , Antioxidantes/metabolismo , Composición Corporal/fisiología , Peso Corporal/fisiología , Carotenoides/sangre , Cromatografía Líquida de Alta Presión/métodos , Estudios Transversales , Registros de Dieta , Femenino , Humanos , Peroxidación de Lípido/efectos de los fármacos , Licopeno , Persona de Mediana Edad , Osteoporosis Posmenopáusica/prevención & controlRESUMEN
AIM: The purpose of this investigation was to determine and compare positional characteristics (physical and physiological) of Division I college female soccer players. METHODS: Sixty-four university soccer players volunteered to participate and were evaluated at the end of their spring season. Test items included height and body mass, acceleration (9.14 m), speed (18.28 and 36.58 m), agility (Pro-agility and Illinois), lower body power (countermovement jump), and estimated aerobic capacity (20 meter beep test). RESULTS: Mean (+/-SD) height and body mass were 168.4+/-5.9 cm and 64.8+/-5.9 kg, respectively. No significant differences were observed between positions, however defenders and keepers tended to be taller and heavier compared to forwards and midfielders. Positional differences did not appear for any of the other performance tests. Yet, defenders tended to show slightly slower times for the speed and agility tests while keepers tended to be slower on the agility tests compared to forwards and midfielders. Aerobic capacity was similar across the four positions. CONCLUSIONS: Similar physical and physiological characteristics were found within this sample of Division I female college soccer players.
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Destreza Motora/fisiología , Fútbol/fisiología , Aceleración , Adulto , Estatura/fisiología , Peso Corporal/fisiología , Femenino , Humanos , Extremidad Inferior/fisiología , Fuerza Muscular/fisiología , Consumo de Oxígeno/fisiologíaRESUMEN
The prevalence of osteoporosis in men is higher than previously assumed; consequently, numerous therapies are being investigated to treat these patients. The Canadian Database of Osteoporosis and Osteopenia patients (CANDOO) was analyzed to examine changes in bone mineral density (BMD) in consecutively seen osteoporotic men administered alendronate, etidronate or no bone-active drugs (control) over 1 year. A total of 244 men attending six Canadian osteoporosis clinics were included in the study (42 alendronate, 102 etidronate and 100 control). Multiple imputation was used to model missing data to provide a more robust statistical model. The imputed datasets (five) were analyzed using multivariable linear regression to determine differences between groups in the percent change of lumbar spine (LS) and femoral neck (FN) BMD from baseline to 1 year. Differences in the percent change in BMD from baseline were most notable at the LS in favor of alendronate (4.3%; 95% CI: 2.1, 6.6 ) and etidronate (2.1%; 95% CI: 0.3, 4.0) therapy when compared with controls. At the LS, alendronate therapy led to significantly greater (2.2%; 95% CI: 0.2, 4.2) gains in BMD as compared to etidronate therapy. Compared to controls, there were no significant differences in FN BMD with alendronate (2.1%; 95% CI: -0.4, 4.7) or etidronate therapy (0.9%; 95% CI: -1.1, 2.8), nor were there significant differences between bisphosphonate groups (1.3%; 95% CI: -1.1, 3.6, in favor of alendronate). While both alendronate and etidronate significantly increased LS BMD in osteoporotic men after 1 year in real-world settings, alendronate therapy resulted in significantly superior gains in LS BMD. The effect of these two bisphosphonates on fractures and FN BMD in osteoporotic men is likely positive, but requires further study.
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Alendronato/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Ácido Etidrónico/uso terapéutico , Osteoporosis/tratamiento farmacológico , Estatura/fisiología , Peso Corporal/fisiología , Densidad Ósea/fisiología , Cuello Femoral/fisiopatología , Fracturas Óseas/etiología , Fracturas Óseas/fisiopatología , Humanos , Estilo de Vida , Vértebras Lumbares/fisiopatología , Masculino , Persona de Mediana Edad , Osteoporosis/fisiopatología , Estudios Prospectivos , Análisis de Regresión , Resultado del TratamientoRESUMEN
We have shown that osteoblastic cells derived from trabecular bone explants of osteoporotic subjects (OP cells) exhibited an altered alkaline phosphatase (ALP) response to 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] compared to control (CON) cells. Our hypothesis that OP cells have other intrinsic abnormalities was investigated using our cell models representing two different stages of differentiation. OP and CON cells were cultured in the absence (-DEX) or presence (+DEX) of 10 nM dexamethasone (DEX) in 10% fetal calf serum (FCS) prior to exposure to serum-free medium containing 1 nM of PTH and/or 17-beta estradiol (E2). Both OP and CON cells responded to DEX with a two-fold increase in basal ALP activity. While E2 or PTH+E2 had no effect on OP cells, both treatments inhibited ALP activity in CON cells (p<0.05). OP and CON cells grown in DEX also expressed PTH-stimulated adenylate cyclase (AC) activities higher than those of (-DEX) cells. OP+DEX cells, however, exhibited activities which were 8-fold higher than those of CON+DEX cells (p<0.001). In OP+DEX cells, E2 stimulated basal AC activity (p<0.05) but did not affect PTH-stimulated activity. In contrast, in CON+DEX cells, E2 had no effect on basal activity but inhibited PTH-stimulated AC activity (p<0.001). Osteocalcin production was 4-fold lower in OP+DEX cells compared to OP-DEX and CON cells (p<0.05) while osteocalcin mRNA levels were significantly lower in OP+DEX and CON+/-DEX cells compared to OP-DEX cells (p<0.05). E2 did not affect osteocalcin protein or mRNA levels in either OP or CON cells. No differences in mRNA levels were found for estrogen receptor-alpha (ER-a) in OP+/-DEX cells whereas these levels were significantly higher in CON+DEX compared to CON-DEX cells (p<0.05). These results indicate that DEX amplified the differences between OP and CON cells and confirm the presence of intrinsic osteoblastic abnormalities in patients with osteoporosis that persist in culture.
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Dexametasona/farmacología , Osteoblastos/efectos de los fármacos , Osteoblastos/patología , Osteoporosis/patología , Adenilil Ciclasas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Fosfatasa Alcalina/metabolismo , Calcitriol/farmacología , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Estradiol/farmacología , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoblastos/enzimología , Osteocalcina/genética , Osteocalcina/metabolismo , Osteoporosis/enzimología , Osteoporosis/genética , Hormona Paratiroidea/farmacología , Fenotipo , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Receptor de Hormona Paratiroídea Tipo 1/genética , Receptor de Hormona Paratiroídea Tipo 1/metabolismo , Factores de TiempoRESUMEN
Osteoporotic fractures can be a major cause of morbidity. It is important to determine the impact of fractures on health-related quality of life (HRQL). A total of 3,394 women and 1,122 men 50 years of age and older, who were recruited for the Canadian Multicentre Osteoporosis Study (CaMos), participated in this cross-sectional study. Minimal trauma fractures of the hip, pelvis, spine, lower body (included upper and lower leg, knee, ankle, and foot), upper body (included arm, elbow, sternum, shoulder, and clavicle), wrist and hand (included forearm, hand, and finger), and ribs were studied. Participants with subclinical vertebral deformities were also examined. The Health Utilities Index Mark II and III Systems were used to assess HRQL. Past osteoporotic fractures varied in prevalence from 1.2% (pelvis) to 27.8% (lower body) in women and 0.3% (pelvis) to 29.3% (wrist) in men. Multivariate linear regression analyses [parameter estimates and corresponding 95% confidence intervals (CI)] indicated that minimal trauma fractures were negatively associated with HRQL and that this relationship depends on fracture type and gender. The multi-attribute scores for the Mark II system were negatively related to hip (-0.05; 95% CI: -0.09, -0.01), lower body (-0.02; 95% CI: -0.03, -0.000), and subclinical vertebral fractures (-0.02; 95% CI: -0.03, -0.00) for women. The multi-attribute scores for the Mark III system were negatively related to hip (-0.09; 95% CI: -0.14, -0.03) and rib fractures (-0.06; 95% CI: -0.11, -0.00) for women, and rib fractures (-0.06; 95% CI: -0.12, -0.00) for men. In conclusion, this study demonstrates a negative association between osteoporotic fractures and quality of life in both women and men.
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Fracturas Óseas/etiología , Fracturas Óseas/rehabilitación , Osteoporosis/complicaciones , Calidad de Vida , Anciano , Estudios Transversales , Femenino , Indicadores de Salud , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Osteoporosis Posmenopáusica/complicacionesRESUMEN
This cross-sectional cohort study of 5566 women and 2187 men 50 years of age and older in the population-based Canadian Multicentre Osteoporosis Study was conducted to determine whether reported past diseases are associated with bone mineral density or prevalent vertebral deformities. We examined 12 self-reported disease conditions including diabetes mellitus (types 1 or 2), nephrolithiasis, hypertension, heart attack, rheumatoid arthritis, thyroid disease, breast cancer, inflammatory bowel disease, neuromuscular disease, Paget's disease, and chronic obstructive pulmonary disease. Multivariate linear and logistic regression analyses were performed to determine whether there were associations among these disease conditions and bone mineral density of the lumbar spine, femoral neck, and trochanter, as well as prevalent vertebral deformities. Bone mineral density measurements were higher in women and men with type 2 diabetes compared with those without after appropriate adjustments. The differences were most notable at the lumbar spine (+0.053 g/cm2), femoral neck (+0.028 g/cm2), and trochanter (+0.025 g/cm2) in women, and at the femoral neck (+0.025 g/cm2) in men. Hypertension was also associated with higher bone mineral density measurements for both women and men. The differences were most pronounced at the lumbar spine (+0.022 g/cm2) and femoral neck (+0.007 g/cm2) in women and at the lumbar spine (+0.028 g/cm2) in men. Although results were statistically inconclusive, men reporting versus not reporting past nephrolithiasis appeared to have clinically relevant lower bone mineral density values. Bone mineral density differences were -0.022, -0.015, and -0.016 g/cm2 at the lumbar spine, femoral neck, and trochanter, respectively. Disease conditions were not strongly associated with vertebral deformities. In summary, these cross-sectional population-based data show that type 2 diabetes and hypertension are associated with higher bone mineral density in women and men, and nephrolithiasis may be associated with lower bone mineral density in men. The importance of these associations for osteoporosis case finding and management require further and prospective studies.
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Densidad Ósea , Osteoporosis/epidemiología , Columna Vertebral/anomalías , Anciano , Anciano de 80 o más Años , Canadá/epidemiología , Estudios de Cohortes , Estudios Transversales , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Hipertensión/complicaciones , Cálculos Renales/complicaciones , Masculino , Persona de Mediana Edad , Osteítis Deformante/complicaciones , Osteoporosis/complicacionesRESUMEN
BACKGROUND: The identification of new methods of evaluating patients with osteoporotic fracture should focus on their usefulness in clinical situations such that they are easily measured and applicable to all patients. Thus, the purpose of this study was to examine the association between iliocostal distance and vertebral and non-vertebral fractures in patients seen in a clinical setting. METHODS: Patient data were obtained from the Canadian Database of Osteoporosis and Osteopenia (CANDOO). A total of 549 patients including 508 women and 41 men participated in this cross-sectional study. There were 142 women and 18 men with prevalent vertebral fractures, and 185 women and 21 men with prevalent non-vertebral fractures. RESULTS: In women multivariable regression analysis showed that iliocostal distance was negatively associated with the number of vertebral fractures (-0.18, CI: -0.27, -0.09; adjusted for bone mineral density at the Ward's triangle, epilepsy, cerebrovascular disease, inflammatory bowel disease, etidronate use, and calcium supplement use) and for the number of non-vertebral fractures (-0.09, CI: -0.15, -0.03; adjusted for bone mineral density at the trochanter, cerebrovascular disease, inflammatory bowel disease, and etidronate use). However, in men, multivariable regression analysis did not demonstrate a significant association between iliocostal distance and the number of vertebral and non-vertebral fractures. CONCLUSIONS: The examination of iliocostal distance may be a useful clinical tool for assessment of the possibility of vertebral fractures. The identification of high-risk patients is important to effectively use the growing number of available osteoporosis therapies.
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The International Society for Clinical Densitometry (ISCD) is a multidisciplinary nonprofit global organization formed to ensure excellence in densitometry imaging, interpretation, and application. The Canadian panel of the ISCD represents ISCD in Canada and oversees Canadian bone densitometry certification programs. The standards of care from the Canadian panel of the ISCD have been developed in order to establish the minimum level of acceptable performance for the practice of bone densitometry in Canada. A variety of techniques are available for skeletal assessment of bone mineral density, which vary in accuracy, precision, and clinical utility as well as availability. This article focuses on central dual X-ray absorptiometry in adults and does not address densitometry in the pediatric population. Other technologies will be addressed in a subsequent article.
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Absorciometría de Fotón/normas , Canadá , Competencia Clínica , Contraindicaciones , Cadera/fisiología , Vértebras Lumbares/fisiología , Control de Calidad , Medición de RiesgoRESUMEN
BACKGROUND: Positive and negative effects on bone mineral density (BMD) have been described as a result of the premenopausal use of oral contraceptives (OCs); increased fracture rates have also been reported. This study assessed the relation between OC use and BMD in a population-based, 9-centre, national sample of women aged 25-45 years. METHODS: Premenopausal women who had been enrolled in the Canadian Multicentre Osteoporosis Study were classified as having ever been OC users (> or = 3 months) or as having never been OC users (0 to < 3 months). Data were obtained through extensive questionnaires and measuring of participants' weight, height and the BMD of lumbar vertebrae and the proximal femur. RESULTS: Of the sample of 524 women, whose mean age was 36.3 (standard deviation [SD] 5.9) years, 454 had used OCs; their mean age when they started using OCs was 19.8 (SD 3.5) years and the mean duration of use was 6.8 (SD 4.8) years. Women who had ever and those who had never used OCs showed no differences in age, age at menarche, parity, current calcium intake, exercise, body mass index (BMI), education, past irregular cycles or amenorrhea. OC users reported more alcohol and cigarette use and more use of medications to create regular cycles. Mean BMD values (adjusted for age, BMI and height) were 0.02-0.04 g/cm2 (that is, 2.3%-3.7%) lower in OC users, and were significantly lower in the spine and trochanter. The BMD of the spine in OC users was 1.03 (SD 0.12) g/cm2 versus 1.07 (SD 0.12) g/cm2 (95% confidence interval [CI] of difference -0.07 to -0.001) in those who had never used OCs. BMD was neither related to the duration of OC use nor to gynecological age at first use. Current and past users had similar BMD values. INTERPRETATION: National, population-based data show lower BMD values for the trochanter and spine in premenopausal women who have used OCs compared with those who have never used OCs.
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Densidad Ósea/efectos de los fármacos , Anticonceptivos Orales/farmacología , Premenopausia/fisiología , Absorciometría de Fotón , Adulto , Canadá/epidemiología , Estudios Transversales , Femenino , Fémur/efectos de los fármacos , Fémur/fisiología , Humanos , Modelos Logísticos , Vértebras Lumbares/efectos de los fármacos , Vértebras Lumbares/fisiología , Persona de Mediana Edad , Premenopausia/efectos de los fármacos , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
CONTEXT: Identification of women with low bone mineral density (BMD) is an important strategy in reducing the incidence of osteoporotic fractures. However, screening all women is not recommended. OBJECTIVES: To assess the diagnostic properties of 4 decision rules--Simple Calculated Osteoporosis Risk Estimation (SCORE), Osteoporosis Risk Assessment Instrument (ORAI), Age, Body Size, No Estrogen (ABONE), and body weight less than 70 kg (weight criterion)--for selecting women for dual-energy x-ray absorptiometry (DXA) testing and to compare results with recommendations made in the National Osteoporosis Foundation (NOF) practice guidelines. DESIGN AND SETTING: Analysis of data from the Canadian Multicentre Osteoporosis Study, a population-based community sample, collected from 9 study centers across Canada between February 1996 and September 1997. PARTICIPANTS: Postmenopausal women aged 45 years or older (N = 2365) without bone disease who had DXA data for the femoral neck, data to apply selection criteria, and who were not currently taking estrogens or who had been taking hormone replacement therapy for 5 or more years. MAIN OUTCOME MEASURES: Sensitivity, specificity, and area under the receiver operating characteristic (AUROC) curve of each of the 4 decision rules and the NOF guidelines for identifying women with a BMD T score of less than -1.0 SD, less than -2.0 SD, and no more than -2.5 SD at the femoral neck, and percentages of women recommended for testing, stratified by BMD level and age. RESULTS: The percent of women with a BMD T score less than -1, less than -2, and no more than -2.5 were 68.3%, 25.4%, and 10.0%, respectively. The AUROC curves were greatest using SCORE and ORAI. The sensitivity for identifying women with a BMD T score of less than -2.0 was 93.7% (95% confidence interval [CI], 91.8%-95.6%) using the NOF guidelines and was 97.5% (95% CI, 96.3%-98.8%), 94.2% (95% CI, 92.3%-96.1%), 79.1% (95% CI, 75.9%-82.3%), and 79.6% (95% CI, 76.4%-82.8%), respectively, using the SCORE, ORAI, ABONE, and weight criterion. However, the NOF guidelines also resulted in 74.4% (95% CI, 71.3%-77.6%) of women with a normal BMD (T score of -1.0 or higher) being tested compared with 69.2% (95% CI, 65.9%-72.5%), 56.3% (95% CI, 52.7%-59.8%), 35.8% (95% CI, 32.4%-39.2%), and 38.1% (95% CI, 34.6%-41.6%), respectively, using the 4 decision rules. Assessments suggest that ABONE and weight criterion are not useful case-finding approaches. CONCLUSION: The SCORE and ORAI decision rules are better than the NOF guidelines at targeting BMD testing in high-risk patients. The acceptability of these rules in clinical practice merits further investigation given their potential effect on the use of densitometry services.
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Absorciometría de Fotón , Densidad Ósea , Técnicas de Apoyo para la Decisión , Osteoporosis/prevención & control , Derivación y Consulta/normas , Anciano , Femenino , Cuello Femoral/diagnóstico por imagen , Humanos , Persona de Mediana Edad , Posmenopausia , Guías de Práctica Clínica como Asunto , Medición de Riesgo , Sensibilidad y EspecificidadRESUMEN
It is now well established that estrogen inhibits bone resorption. However, its effect on bone formation remains controversial. We studied the effect of 17beta-estradiol (E2) on mineralized bone nodule formation in long-term cultures of osteosarcoma SaOS-2 cells. We showed that SaOS-2 cells formed mineralized nodules which under electron microscopy revealed a bone structure with active osteoblasts, entrapped osteocytes, extracellular collagen fibrils and hydroxyapatite deposits, making this system a valid model to study bone formation in vitro. Intermittent addition of E2 for 6 hours during a 48-hour cycle of changes of medium, starting from day 3, resulted in a dose-dependent stimulation of mineralized bone nodule number and area, as well as alkaline phosphatase activity. In conclusion, we report for the first time a stimulatory effect of E2 on mineralized bone nodule formation in human osteoblasts in culture.
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Calcificación Fisiológica/efectos de los fármacos , Estradiol/farmacología , Fosfatasa Alcalina/efectos de los fármacos , Análisis de Varianza , Neoplasias Óseas/patología , Relación Dosis-Respuesta a Droga , Humanos , Microscopía Electrónica , Osteoblastos/efectos de los fármacos , Osteosarcoma/patología , Coloración y Etiquetado , Células Tumorales Cultivadas/efectos de los fármacosRESUMEN
We compared the effects of 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] and its analog, 1alpha,25-dihydroxy-16-ene-vitamin D3 [1alpha,25(OH)2-16-ene-D3], as well as their interactions with 17-beta estradiol (E2) on osteoblastic function in our human normal (HOB) and osteosarcoma SaOS-2 cell models representing two different stages of differentiation, the more differentiated HOB+DEX cells and SaOS+DEX cells, and the corresponding less differentiated HOB-DEX and SaOS-DEX cells. The differential effects of 1alpha,25(OH)2D3 and 1alpha,25(OH)2-16-ene-D3 and the modulation by E2 on ALP activity in HOB-DEX and HOB+DEX cells were small but significant. The most significant effects were seen in SaOS+DEX cells, in which 1alpha,25(OH)2-16-ene-D3 was 100-fold more potent than 1alpha,25(OH)2D3, the maximal enhancement being exerted at 0.1 nM and 10 nM, respectively. E2 enhanced the stimulatory effects of both compounds, with ALP being increased 2-fold at 0.1 nM (p<0.001). Osteocalcin (OC) production in HOB-DEX cells was stimulated 1.3 to 1.4-fold by 1alpha,25(OH)2D3 and 1alpha,25(OH)2-16-ene-D3 at a concentration of 0.01 nM, with E2 inhibiting the effect of 1alpha,25(OH)2-16-ene-D3. In SaOS-DEX and SaOS+DEX cells, 1alpha,25(OH)2D3 and 1alpha,25(OH)2-16-ene-D3 stimulated OC production 1.6-fold at 0.1 nM with E2 slightly enhancing the effect of 1alpha,25(OH)2D3. Western blot analysis of 1alpha,25(OH)2D3 receptor (VDR) levels showed that in SaOS+DEX cells, the effect of 1alpha,25(OH)2D3 was larger than that of 1alpha,25(OH)2-16-ene-D3. These results show that 1alpha,25(OH)2-16-ene-D3 is biologically active in human osteoblasts.
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Neoplasias Óseas/patología , Calcitriol/farmacología , Estradiol/farmacología , Osteoblastos/efectos de los fármacos , Osteosarcoma/patología , Adulto , Fosfatasa Alcalina/metabolismo , Western Blotting , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Masculino , Osteocalcina/biosíntesis , Células Tumorales CultivadasRESUMEN
BACKGROUND: The Medical Outcomes Study 36-item Short Form (SF-36) is a widely used measure of health-related quality of life. Normative data are the key to determining whether a group or an individual scores above or below the average for their country, age or sex. Published norms for the SF-36 exist for other countries but have not been previously published for Canada. METHODS: The Canadian Multicentre Osteoporosis Study is a prospective cohort study involving 9423 randomly selected Canadian men and women aged 25 years or more living in the community. The sample was drawn within a 50-km radius of 9 Canadian cities, and the information collected included the SF-36 as a measure of health-related quality of life. This provided a unique opportunity to develop age- and sex-adjusted normative data for the Canadian population. RESULTS: Canadian men scored substantially higher than women on all 8 domains and the 2 summary component scales of the SF-36. Canadians scored higher than their US counterparts on all SF-36 domains and both summary component scales and scored higher than their UK counterparts on 4 domains, although many of the differences are not large. INTERPRETATION: The differences in the SF-36 scores between age groups, sexes and countries confirm that these Canadian norms are necessary for comparative purposes. The data will be useful for assessing the health status of the general population and of patient populations, and the effect of interventions on health-related quality of life.
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Indicadores de Salud , Estado de Salud , Calidad de Vida , Actividades Cotidianas , Adulto , Distribución por Edad , Anciano , Canadá/epidemiología , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Salud Mental , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Estudios Prospectivos , Valores de Referencia , Distribución por Sexo , Factores Socioeconómicos , Encuestas y Cuestionarios , Reino Unido/epidemiología , Estados Unidos/epidemiología , Salud UrbanaRESUMEN
The Canadian Multicentre Osteoporosis Study (CaMos) is a prospective cohort study which will measure the incidence and prevalence of osteoporosis and fractures, and the effect of putative risk factors, in a random sample of 10,061 women and men aged > or = 25 years recruited in approximately equal numbers in nine centers across Canada. In this paper we report the results of studies to establish peak bone mass (PBM) which would be appropriate reference data for use in Canada. These reference data are used to estimate the prevalence of osteoporosis and osteopenia in Canadian women and men aged > or = 50 years. Participants were recruited via randomly selected household telephone listings. Bone mineral density (BMD) of the lumbar spine and femoral neck were measured by dual-energy X-ray absorptiometry using Hologic QDR 1000 or 2000 or Lunar DPX densitometers. BMD results for lumbar spine and femoral neck were converted to a Hologic base. BMD of the lumbar spine in 578 women and 467 men was constant to age 39 years giving a PBM of 1.042 +/- 0.121 g/cm2 for women and 1.058 +/- 0.127 g/cm2 for men. BMD at the femoral neck declined from age 29 years. The mean femoral neck BMD between 25 and 29 years was taken as PBM and was found to be 0.857 +/- 0.125 g/cm2 for women and 0.910 +/- 0.125 g/cm2 for men. Prevalence of osteoporosis, as defined by WHO criteria, in Canadian women aged > or = 50 years was 12.1% at the lumbar spine and 7.9% at the femoral neck with a combined prevalence of 15.8%. In men it was 2.9% at the lumbar spine and 4.8% at the femoral neck with a combined prevalence of 6.6%.
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Osteoporosis/epidemiología , Absorciometría de Fotón , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Densidad Ósea , Canadá/epidemiología , Femenino , Cuello Femoral/fisiología , Cuello Femoral/fisiopatología , Humanos , Vértebras Lumbares/fisiología , Vértebras Lumbares/fisiopatología , Masculino , Persona de Mediana Edad , Osteoporosis/fisiopatología , Osteoporosis Posmenopáusica/epidemiología , Osteoporosis Posmenopáusica/fisiopatología , Prevalencia , Estudios Prospectivos , Valores de ReferenciaRESUMEN
Bone densitometry using dual energy X-ray absorptiometry (DXA) is the 'gold standard' for osteoporosis diagnosis. However, mass screening for osteoporosis has not been recommended, and no consensus has been reached regarding specific targeted screening programs. Recently, the Simple Calculated Osteoporosis Risk Estimation (SCORE) was developed to identify postmenopausal women likely to have low BMD (< or > -2.0 SD of the young adult normal), who may be selected for DXA testing. This instrument uses a case-selective approach to screen for osteoporosis by summing a score based on: age, race, rheumatoid arthritis, history of nontraumatic fracture over 45 years of age, estrogen use, and weight. In our study, SCORE was validated using 398 postmenopausal women at least 45 years of age residing within 50 km of Toronto, Ontario, Canada (one of 9 centers of the Canadian Multicentre Osteoporosis Study, a national population-based study). At the recommended threshold of 6, SCORE had a sensitivity of 90%, specificity of 32% and a positive predictive value of 64%. From receiver operating characteristic (ROC) analysis, no threshold identified SCORE as a useful instrument in our population; area under the ROC curve was 0. 71. Specificity of the SCORE is poor; at the recommended threshold of 6, 68% of those with normal bone mineral density (BMD) would be selected for bone densitometry. Development and validation of SCORE by Lydick and colleagues may have been confounded by the nature of the study sample; sampling from specialty clinics; and by the choice of outcome, combining data from different DXA machines, and using only data from the femoral neck to identify low BMD. A simple and effective approach to select patients for bone densitometry has yet to be established.
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Densidad Ósea , Osteoporosis Posmenopáusica/diagnóstico , Selección de Paciente , Absorciometría de Fotón , Anciano , Estudios de Evaluación como Asunto , Femenino , Humanos , Persona de Mediana Edad , Curva ROC , Medición de Riesgo , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: To determine the prevalence and seasonal variation of vitamin D deficiency among older residents of long-term care facilities. DESIGN: Cross-sectional survey with 6-month follow-up. SETTING: Three long-term care facilities in Toronto. PATIENTS: Persons more than 65 years old, medically stable, who had resided in the facility for at least 6 months and had no conditions known to interfere with vitamin D metabolism. MEASUREMENTS: Information regarding demographics, past health, and medication use was collected. Mental and functional status were assessed by questionnaire. Venous blood samples were analyzed for alkaline phosphatase, calcium profile, albumin, intact parathyroid hormone, 25 hydroxyvitamin D (25OHD), and vitamin D binding protein in September 1994 and March 1995. In a subgroup of patients, bone specific alkaline phosphatase was measured, and dietary intake of vitamin D was assessed. RESULTS: A total of 155 subjects completed the study. The mean age of the subjects was 83.2 years (SD 7.1), and 47% were female. The mean 25OHD level in the March sample (39.9 nmol/L, SD 19.7) was significantly lower than the mean 25OHD level in the September sample (44.9 nmol/L, SD 16.9) (P = .001). The prevalence of vitamin D deficiency in the osteomalacic range (25OHD < 25 nmol/L) increased from 9% in the fall sample to 18% after the winter (chi 2 = 4.65, P = .03). The prevalence of borderline deficiency or hypovitaminosis D (25OHD < 40 nmol/L) increased from 38% in the fall sample to 60% in the spring sample (chi 2 = 14.9, P < .001). Dependence in transfers was associated with an increased risk of hypovitaminosis D, odds ratio 2.08 (95% confidence interval 1.08-4.01), dependence in ambulation 2.57 (1.26-5.23), and regular use of a wheelchair 2.17 (1.09-4.31). When entered into a forward conditional logistic regression model, only dependence in ambulation remained significant, with an adjusted odds ratio of 2.57 (95% CI: 1.26-5.18). CONCLUSIONS: Vitamin D deficiency and borderline vitamin D status are common among older residents of long-term care facilities in Canada. Even though this population has limited outdoor exposure, seasonal variation in the prevalence of deficiency remains significant. Evaluation of interventions to improve the status of vitamin D nutrition in this population is needed.
Asunto(s)
Casas de Salud , Deficiencia de Vitamina D/epidemiología , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Hogares para Ancianos , Humanos , Masculino , Ontario/epidemiología , Prevalencia , Estaciones del Año , Deficiencia de Vitamina D/sangreRESUMEN
With these thoughts in mind, a realistic, systematic approach can be designed to better develop and interpret cephalometric tracings. After all landmarks are traced and located, connect Sella to Nasion to D point. The triangle formed by connecting these landmarks without other planar values interfering will facilitate evaluation of these three landmarks to each other. With the apex of the triangle formed at D point, the angle formed by Sella-D point and D Axis should be anterior to an iscosoles triangle position. If not, the patient is likely to evidence a vertical growth and mandibular retrognathism, or the Sella-Nasion pattern plane has a severely flat cant. In cases where this same apex (SDN) is severely anterior to an "iscosoles angle," this patient is likely to have either mandibular prognathism or a steep cant of the Sella-Nasion Plane (see Figs. 11 and 12). To determine the relative cant of Sella-Nasion, locate and trace the desired planar position of Frankfurt Horizontal using one of the three choices listed previously. If the Sella-Nasion Plane is 10 degrees or more greater than the cant of Frankfurt Horizontal, the Sella-Nasion plane will be inaccurate as a reference plane for A point, B point and D point gnathic relations, as well as Occlusal Plane to Sella-Nasion. Once it has been established which horizontal reference plan is to be used, the relative positions of the remaining planar values can be traced and compared. In so doing, more accurate interpretation of cephalometric data can be achieved without the puzzling conflicts with other analysis values that might otherwise occur.
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Cefalometría/métodos , Maloclusión/diagnóstico , Huesos Faciales/anatomía & histología , Humanos , Ortodoncia/métodos , Valores de Referencia , Reproducibilidad de los Resultados , Cráneo/anatomía & histologíaRESUMEN
We compared the separate effects of 1alpha,25-dihydroxyvitamin D3 (1alpha,25(OH)2D3) and its analog, 1alpha,25-dihydroxy-16ene,23yne-vitamin D3 (1alpha25(OH)2-16ene,23yne-D3), as well as their interactions with 17-beta estradiol (E2) in our human osteosarcoma SaOS-2 cell models representing two stages of differentiation, the SaOS+DEX and SaOS-DEX cells. SaOS+DEX cells have been previously shown to express higher PTH-stimulated adenylate cyclase (PTH-AC) and basal alkaline phosphatase (ALP) activities compared with SaOS-DEX cells. ALP: In SaOS+DEX cells, 0.1 nmol/L analog, but not 1alpha,25(OH)2D3, increased ALP activity 1.7-fold (p < 0.05). Instead, 1 nmol/L 1alpha,25(OH)2D3 increased ALP 1.4-fold (p < 0.05). In these cells, E2 enhanced 1alpha,25(OH)2D3-stimulated ALP activity (ANOVA, F = 51.22, p <0.0001), while inhibiting the effect of the analog. [3H]-Thymidine uptake: In SaOS+DEX cells, 1alpha,25(OH)2D3 had biphasic effects (ANOVA, F = 13.08, p < 0.0001), which were not altered by E2. In contrast, the analog was stimulatory only with E2 (ANOVA, F = 3.59, p < 0.025). Osteocalcin (OC): 1alpha,25(OH)2D3 and its analog stimulated OC production in SaOS-DEX cells with smaller effects in SaOS+DEX cells. In SaOS-DEX cells, E2 enhanced the effect of 1alpha,25(OH)2D3, but not that of the analog. PTH-AC: In SaOS-DEX cells, 100 nmol/L analog inhibited PTH-AC activities by 50% (p < 0.01), whereas 1alpha,25(OH)2D3 had little effect. In SaOS+DEX cells, both compounds inhibited PTH-AC approximately 35%. E2 inhibited the effect of the analog in SaOS-DEX cells, but enhanced the effects of both compounds in SaOS+DEX cells. These results show that the analog 1alpha,25(OH)2-16ene,23yne-D3 was effective in regulating osteoblastic function; its effects were modulated by E2 and dependent upon the stage of osteoblast differentiation.
Asunto(s)
Calcitriol/análogos & derivados , Dihidroxicolecalciferoles/farmacología , Estradiol/farmacología , Osteoblastos/efectos de los fármacos , Adenilil Ciclasas/metabolismo , Fosfatasa Alcalina/metabolismo , Calcitriol/farmacología , Diferenciación Celular , Humanos , Osteoblastos/metabolismo , Osteocalcina/biosíntesis , Osteocalcina/efectos de los fármacos , Osteosarcoma , Hormona Paratiroidea/farmacología , Timidina/metabolismo , Células Tumorales CultivadasRESUMEN
OBJECTIVE: To recommend appropriate levels of calcium intake in light of the most recent studies. OPTIONS: Dietary calcium intake, calcium supplementation, calcium and vitamin D supplementation; ovarian hormone therapy in postmenopausal women. OUTCOMES: Fracture and loss of bone mineral density in osteoporosis; increased bone mass, prevention of fractures and improved quality of life associated with osteoporosis prevention. EVIDENCE: Relevant clinical studies and reports were examined, in particular those published since the 1988 Osteoporosis Society of Canada position paper on calcium nutrition. Only studies in humans were considered, including controlled, randomized trials and prospective studies, using bone mass and fractures as end-points. Studies in early and later phases of skeletal growth were noted. The analysis was designed to eliminate menopause as a confounding variable. VALUES: Preventing osteoporosis and maximizing quality of life were given a high value. BENEFITS, HARMS AND COSTS: Adequate calcium nutrition increases bone mineral density during skeletal growth and prevents bone loss and osteoporotic fractures in the elderly. Risks associated with high dietary calcium intake are low, and a recent study extends this conclusion to the risk of kidney stones. Lactase-deficient patients may substitute yogurt and lactase-treated milk for cow's milk. True milk allergy is probably rare; its promotion of diabetes mellitus in susceptible people is being studied. RECOMMENDATIONS: Current recommended intakes of calcium are too low. Revised intake guidelines designed to reduce bone loss and protect against osteoporotic fractures are suggested. Canadians should attempt to meet their calcium requirements principally through food sources. Pharmaceutical calcium supplements and a dietician's advice should be considered where dietary preferences or lactase deficiency restrict consumption of dairy foods. Further research is necessary before recommending the general use of calcium supplements by adolescents. Calcium supplementation cannot substitute for hormone therapy in the prevention of postmenopausal bone loss and fractures. Adequate amounts of vitamin D are necessary for optimal calcium absorption and bone health. Elderly people and those who use heavy sun screens should have a dietary intake of 400 to 800 IU of vitamin D per day.