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1.
Hormone replacement therapy (HRT) prevents bone loss in postmenopausal women. Up to 20% of women demonstrate no increase in bone mineral density (BMD) on HRT. We examined whether early changes in serum bone alkaline phosphatase (B-ALP) predict long-term BMD changes in postmenopausal women on HRT. Ninety women within 1 year of menopause were randomly assigned to continuous or sequential estrogen/progestin (beta estradiol/norethisterone acetate) if naturally postmenopausal, or beta estradiol if within 1 month of surgical menopause. Spine, femoral neck BMD (DXA), and B-ALP were determined over 2 years. The mean percent BMD changes were 3.8%, 2.9%, 1.6% in the spine and 2.4%, 4.0%, 1.1% in the femoral neck in sequential, continuous, and estrogen alone treatment groups, respectively, significantly different from zero except for femoral neck BMD change in the estrogen alone group. HRT was associated with spine and femoral neck BMD loss in 17.4% and 25.3% of women, respectively. In estrogen/progestin-treated women, baseline B-ALP correlated with spine BMD change (r = 0.42, P < 0.01). At 3 months, B-ALP dropped significantly in the estrogen/progestin-groups with a maximal decrease at 12 months, but no change from baseline in the estrogen alone group. Using quartile analysis, women with the greatest drop in B-ALP (≥50%) at 6 months demonstrated the greatest gain in spine BMD at 2 years. A 40% decrease at 6 months in B-ALP had a 56% sensitivity, 83% specificity, 95% positive predictive value for spine BMD gain at 2 years. The decrease in B-ALP can be used to monitor BMD response to HRT. Received: 6 January 1999 / Accepted: 13 August 1999  相似文献   

2.
Total and regional bone mineral density (BMD) by dual-energy-X-ray absorptiometry (DXA) and bone turnover were tested in 50 highly trained women athletes and 21 sedentary control women (18–69 years; BMI < 25 kg/m2). VO2max (ml · kg−1· min−1) and lean tissue mass (DXA) were significantly higher in the athletes versus controls (both P < 0.0001). Total body BMD did not decline significantly with age in the athletes whereas lumbar spine (L2–L4) BMD approached statistical significance (r =−0.26; P= 0.07). Significant losses of the femoral neck (r =− 0.42), Ward's triangle (r =−0.53), and greater trochanter BMD (r =−0.33; all P < 0.05) occurred with age in the athletes. In the athletes, total body BMD, L2–L4 BMD, and BMD of all sites of the femur were associated with lean tissue mass (r = 0.32 to r = 0.57, all P < 0.05) and VO2max (r = 0.29 to r = 0.48, all P < 0.05). Femoral neck and greater trochanter BMD were higher in the athletes than in controls (both P < 0.05) and lumbar spine and Ward's triangle BMD approached statistical significance (both P= 0.07). Bone turnover was assessed by serum bone-specific alkaline phosphatase (B-ALP), urinary deoxypyridinoline cross-links (Dpd), and urinary aminoterminal cross-linked telopeptides (NTX). There were no relationships between B-ALP or Dpd with age whereas NTX increased with age (r = 0.46, P < 0.05) in the entire group. Levels of B-ALP and NTX were negatively associated with total body, L2–L4, femoral neck, Ward's triangle, and greater trochanter BMD (P < 0.05). B-ALP and Dpd were not significantly different between athletes and controls whereas NTX was lower in the athletes than in controls (P < 0.001). The high levels of physical activity observed in women athletes increase aerobic capacity and improve muscle mass but are not sufficient to prevent the loss of bone with aging. Received: 28 November 1997 / Accepted: 8 April 1998  相似文献   

3.
Bone loss before and around the time of menopause is not well characterized by longitudinal studies. We measured bone mineral density at various skeletal sites – total body, femoral neck, trochanter, anteroposterior (AP) and lateral spine, and forearm – with dual-energy X-ray absorptiometry in a large prospective cohort of 272 untreated pre- and perimenopausal women aged 31–59 years, at 1 year intervals for 3 years. Sex steroids and the following markers of bone remodeling were measured: serum osteocalcin (OC), procollagen I carboxyterminal extension peptide, bone alkaline phosphatase (BAP) and urinary crosslinks (CTX and NTX). Seventy-six women were classified as perimenopausal and 196 as premenopausal. Over the 3 years, premenopausal women had no significant bone loss at any site and a small but significant increase in bone mineral density at the trochanter, total hip, AP spine and radius. Perimenopausal women significantly lost bone from cancellous and cortical sites, i.e., the femoral neck, trochanter and lumbar spine. In perimenopausal women with increased follicle stimulating hormone, the rate of bone loss at the femoral neck correlated negatively with OC and BAP. In perimenopausal women, serum estradiol levels decreased during the 3 years of follow-up and bone loss from the trochanter and the AP spine was correlated with serum estradiol after 3 years. In conclusion, among premenopausal women there is no bone loss. In contrast, there is a rapid and diffuse bone loss in perimenopausal women, related to decreased estrogen secretion. Bone markers may be useful to identify these women losing bone. Received: 13 October 1997 / Accepted: 19 October 1998  相似文献   

4.
We conducted a population-based cohort study in 7598 white healthy women, aged 75 years and over, recruited from the voting lists. We measured at baseline bone mineral density (BMD g/cm2) of the proximal femur (neck, trochanter and Ward's triangle) and the whole body, as well as fat and lean body mass, by dual-energy X-ray absorptiometry (DXA). One hundred and fifty-four women underwent a hip fracture during an average 2 years follow-up. Each standard deviation decrease in BMD increased the risk of hip fracture adjusted for age, weight and centre by 1.9 (95% CL 1.5, 2.3) for the femoral neck, 2.6 times (2.0, 3.3) for the trochanter, 1.8 times (1.4, 2.2) for Ward's triangle, 1.6 times (1.2, 2.0) for the whole body, and 1.3 times (1.0, 1.5) for the fat mass. The areas under the receiver operating characteristic (ROC) curves were not significantly different between trochanter and femoral neck BMD, whereas ROC curves of femoral neck and trochanter BMD were significantly better than those for Ward's triangle and whole-body BMD. emsp;Women who sustained an intertrochanteric fracture were older (84 ± 4.5 years) than women who had a cervical fracture (81 ± 4.5 years) and trochanter BMD seemed to be a stronger predictor of intertrochanteric ([RR = 4.5 (3.1, 6.5)] than cervical fractures ([RR = 1.8 (1.5, 2.3]). emsp;In very elderly women aged 80 years and more, hip BMD was still a significant predictor of hip fracture but the relative risk was significantly lower than in women younger than 80 years. emsp;In the 48% of women who had a femoral neck BMD T-score less than –2.5, the relative risk of hip fracture was increased by 3, and the unadjusted incidence of hip fracture was 16.4 per 1000 woman-years compared with 1.1 in the population with a femoral neck BMD T-score 5–1. Received: 19 May 1997 / Accepted: 16 October 1997  相似文献   

5.
Fractures due to osteoporosis are one of the major complications after heart transplantation, occurring mostly during the first 6 months after the graft, with an incidence ranging from 18% to 50% for vertebral fractures. Bone mineral density (BMD) decreases dramatically following the graft, at trabecular sites as well as cortical sites. This is explained by the relatively high doses of glucocorticoids used during the months following the graft, and by a long-term increase of bone turnover which is probably due to cyclosporine. There is some evidence for a beneficial effect on BMD of antiresorptive treatments after heart transplantation. The aim of this study was to assess prospectively the effect on BMD of a 3-year treatment of quarterly infusions of 60 mg of pamidronate, combined with 1 g calcium and 1000 U vitamin D per day, in osteoporotic heart transplant recipients, and that of a treatment with calcium and vitamin D in heart transplant recipients with no osteoporosis. BMD of the lumbar spine and the femoral neck was measured by dual-energy X-ray absorptiometry in all patients every 6 months for 2 years and after 3 years. Seventeen patients, (1 woman, 16 men) aged 46 ± 4 years (mean ± SEM) received only calcium and vitamin D. A significant decrease in BMD was observed after 6 months following the graft, at the lumbar spine (−6.6%) as well as at the femoral neck (−7.8%). After 2 years, BMD tended to recover at the lumbar spine, whereas the loss persisted after 3 years at the femoral neck. Eleven patients (1 woman and 10 men) aged 46 ± 4 years (mean ± SEM) started treatment with pamidronate on average 6 months after the graft, because they had osteoporosis of the lumbar spine and/or femoral neck (BMD T-score below −2.5 SD). Over the whole treatment period, a continuous increase in BMD at the lumbar spine was noticed, reaching 18.3% after 3 years (14.3% compared with the BMD at the time of the graft). BMD at the femoral neck was lowered in the first year by −3.4%, but recovered totally after 3 years of treatment. In conclusion, a 3-year study of treatment with pamidronate given every 3 months to patients with existing osteoporosis led to a significant increase in lumbar spine BMD and prevented loss at the femoral neck. However, since some of these patients were treated up to 14 months after the transplant, they may already have passed through the phase of most rapid bone loss. In patients who were not osteoporotic at baseline, treatment with calcium and vitamin D alone was not able to prevent the rapid bone loss that occurs immediately after transplantation. Received: 31 June 2000 / Accepted: 23 August 2000  相似文献   

6.
The width of long bone diaphyses apparently increase with age, a phenomenon that is suggested to have some positive impact on bone strength. On the other hand, these changes in size that are site-specific may cause a deterioration in the local mechanical integrity of the whole bone. Physical activity and calcium intake are known to be able to modify bone mass and size. It is, however, not known whether these lifestyle habits can modify the postulated disproportionate changes in bone size. To address this question, bone mineral content (BMC)-derived estimates of cross-sectional areas (CSA) of femur and radius in 158 premenopausal (mean age 43, standard deviation 2 years) and 134 postmenopausal (63 (2) years), clinically healthy women with contrasting long-term histories in physical activity and calcium intake were determined from dual-energy X-ray absorptiometry (DXA) data. The DXA-obtained BMC correlated strongly with the actual CSA (r= 0.94) determined with peripheral quantative computed tomography. The ratios between functionally interrelated CSA data (i.e., (radial shaft CSA/distal radius CSA), (trochanter CSA/femoral neck CSA), (femoral shaft CSA/trochanter CSA) and (femoral shaft CSA/femoral neck CSA)) were considered primary outcome variables. Neither physical activity nor calcium intake separately or interactively were associated with any CSA ratio. Age showed no interaction with physical activity or calcium intake but was independently associated with all CSA ratios, except the ratio of femoral shaft CSA to trochanteric CSA. This study indicated clearly that a preferential reduction in the cross-sectional area occupied by bone mineral occurs disproportionately at the long bone ends as compared with diaphyseal sites, and this apparently inherent, age-associated relative loss seems not to be prevented by physical activity or calcium intake. In particular, given the utmost clinical relevance of the proximal femur region, an observed loss in femoral neck CSA of about 10% in contrast to about a 5% loss in trochanteric CSA warrants further investigation regarding its potential role as a predictor for hip fracture. Not only the local differences in bone composition but also the biomechanical aspects are important factors underlying these apparent changes in CSA at the studied skeletal sites. Received: 10 September 1998 / Accepted: 17 March 1999  相似文献   

7.
In a 12-month randomized, double-blind, placebo-controlled trial, we have studied the effects of intranasal salmon calcitonin (SCT) on bone mineral density (BMD) and biochemical markers of bone turnover. Twenty-eight men with idiopathic osteoporosis aged 27-74 years (mean, 52.4 years) were randomized to receive either nasal SCT (200 IU) or a nasal placebo daily for a period of 1 year. All the men received a daily supplement of 0.5 g of calcium. The men who received SCT had a mean (+/-SEM) increase in BMD of 7.1 +/- 1.7% at the lumbar spine. In contrast, the men who received the placebo had an increase of 2.4 +/- 1.5% (p > 0.05) for the comparison with baseline. The increase in lumbar BMD in the calcitonin group was significantly greater than that in the placebo group (p < 0.05). There were no significant changes in the femoral neck, trochanter, or Ward's triangle relative to both baseline and placebo after 12 months. Treatment with nasal SCT resulted in a significantly pronounced suppression of bone resorption markers (urinary deoxypyridinoline [DPD], type I cross-linked N-telopeptide [NTX], and type I cross-linked C-telopeptide [CTX]) and to a lesser extent in bone formation markers (serum bone-specific alkaline phosphatase [BALP], osteocalcin [OC], serum C-terminal procollagen type I extension peptides [PICP], and serum N-termnal procollagen type I extension peptides [PINP]), whereas the placebo did not. Therapy was tolerated well and there were no treatment-related adverse events. We conclude that intranasal SCT (200 IU daily) is safe and effective in increasing lumbar BMD and reducing bone turnover in men with idiopathic osteoporosis.  相似文献   

8.
Altogether 92 initially 25- to 30-year-old women of 132 original subjects participated in this 4-year follow-up study, which evaluated the influence of physical activity and calcium intake on the bone mineral content (BMC) of premenopausal women. The subjects were originally selected for a cross-sectional study according to their level of physical activity (high PA+ and low PA) and calcium intake (high Ca+ and low Ca), and the original groups were maintained in this follow-up study. The mean loss of BMC (95% CI) in the pooled data was 1.5% (0.7% to 2.4%) at the femoral neck, 0.6% (–0.8% to 1.9%) at the trochanter and 6.0% (4.5% to 7.4%) at the distal radius during the 4-year follow-up. According to repeated measures analyses of covariance neither physical activity nor physical fitness at baseline was associated with the rate of bone loss from the proximal femur. High calcium intake and the maintenance of body weight were both associated with a lower rate of bone loss from the proximal femur and distal radius. In addition, a long duration of breast feeding was associated with a higher rate of bone loss from the distal radius. Received: 1 June 2001 / Accepted: 29 August 2001  相似文献   

9.
The natural isoflavone phytoestrogen genistein has been shown to stimulate osteoblastic bone formation, inhibit osteoclastic bone resorption, and prevent bone loss in ovariectomized rats. However, no controlled clinical trial has been performed so far to evaluate the effects of the phytoestrogen on bone loss in postmenopausal women. We performed a randomized double-blind placebo-controlled study to evaluate and compare with hormone-replacement therapy (HRT) the effect of the phytoestrogen genistein on bone metabolism and bone mineral density (BMD) in postmenopausal women. Participants were 90 healthy ambulatory women who were 47-57 years of age, with a BMD at the femoral neck of <0.795 g/cm2. After a 4-week stabilization on a standard fat-reduced diet, participants of the study were randomly assigned to receive continuous HRT for 1 year (n = 30; 1 mg of 17beta-estradiol [E2] combined with 0.5 mg of norethisterone acetate), the phytoestrogen genistein (n = 30; 54 mg/day), or placebo (n = 30). Urinary excretion of pyridinoline (PYR) and deoxypyridinoline (DPYR) was not significantly modified by placebo administration either at 6 months or at 12 months. Genistein treatment significantly reduced the excretion of pyridinium cross-links at 6 months (PYR = -54 +/- 10%; DPYR = -55 +/- 13%; p < 0.001) and 12 months (PYR = -42 +/- 12%; DPYR = -44 +/- 16%; p < 0.001). A similar and not statistically different decrease in excretion of pyridinium cross-links was also observed in the postmenopausal women randomized to receive HRT. Placebo administration did not change the serum levels of the bone-specific ALP (B-ALP) and osteocalcin (bone Gla protein [BGP]). In contrast, administration of genistein markedly increased serum B-ALP and BGP either at 6 months (B-ALP = 23 +/- 4%; BGP = 29 +/- 11%; p < 0.005) or at 12 months (B-ALP = 25 +/- 7%; BGP = 37 +/- 16%; p < 0.05). Postmenopausal women treated with HRT had, in contrast, decreased serum B-ALP and BGP levels either at 6 months (B-ALP = -17 +/- 6%; BGP = -20 +/- 9%; p < 0.001) or 12 months (B-ALP = -20 +/- 5%; BGP = -22 +/- 10%; p < 0.001). Furthermore, at the end of the experimental period, genistein and HRT significantly increased BMD in the femur (femoral neck: genistein = 3.6 +/- 3%, HRT = 2.4 +/- 2%, placebo = -0.65 +/- 0.1%, and p < 0.001) and lumbar spine (genistein = 3 +/- 2%, HRT = 3.8 +/- 2.7%, placebo = -1.6 +/- 0.3%, and p < 0.001). This study confirms the genistein-positive effects on bone loss already observed in the experimental models of osteoporosis and indicates that the phytoestrogen reduces bone resorption and increases bone formation in postmenopausal women.  相似文献   

10.
The purpose of this study was to determine if differences exist in premenopausal women between z-scores for lumbar spine and proximal femoral bone mineral densities (BMD). Participants were 237 women ranging in age from 20 to 45 years. BMDs of the lumbar spine and proximal femur (femoral neck, Ward's area, and trochanter) were assessed using dual-energy X-ray absorptiometry (Lunar DPX). Mean (±SD) age, height, and weight of the participants were 29.4 ± 6.9 years, 164.4 ± 6.1 cm, and 64.9 ± 12.1 kg, respectively. Lumbar spine BMD and BMD at the femoral neck, Ward's area, and trochanter were significantly correlated with large SEEs (r = 0.59–0.65; SEE = 0.09–0.11). No positive correlation with age and BMD at any site was seen in this population but a significant negative correlation with age was seen in the proximal femur beginning at age 30. Twenty to 24% of the 20–29-year-olds exhibited a difference in z-scores of greater than 1 between the spine and sites in the proximal femur. This percentage increased to 32–46% in the 30–45-year-olds but the nature of the observed differences changed. The differences in spine and proximal femoral z-scores that are seen in the older age group appear to be the result of the earlier onset of bone loss in the proximal femur rather than an initial difference in peak bone mass which has been maintained. Received: 28 August 1996 / Accepted: 25 April 1997  相似文献   

11.
Organ transplantation is associated with relevant bone loss. Bone loss of up to 20% of pretransplant bone mineral density (BMD) values within the first year after kidney, liver, heart and lung transplantation has been reported. Patients undergoing transplantation of hematopoietic stem cells provide an interesting model to study transplantation-induced bone loss, especially because most patients do not have pre-existing bone disease. A longitudinal study was performed in 81 patients undergoing bone marrow or peripheral blood stem cell transplantation. BMD was determined by dual-energy X-ray absorptiometry before transplantation, at discharge from the hospital, and at 6 and 12 months after transplantation in all 81 patients. In 35 patients BMD was re-evaluated 24 months after transplantation. Vitamin D and parathyroid hormone, bone alkaline phosphatase as a marker of bone formation, and N-terminal telopeptide of type I collagen as a marker of bone resorption were assessed before transplantation and in the short-term follow-up 14 and 28 days after transplantation. The majority of patients (72%) showed normal BMD before transplantation. However, lower BMD was observed in patients who had received high-dose cytoreductive chemotherapy before transplantation compared with those who had received no chemotherapy or only hydroxyurea. Despite supplementation with elemental calcium (1000 mg/day) and vitamin D (1000 IU/day), the mean rate of bone loss during the first year was 7.2 ± 6.3% at the lumbar spine, 11.9 ± 8.1% at the femoral neck and 3.8 ± 2.5% at the total body compartment. Evaluation of the pattern of bone loss during the first year demonstrated that the amount of bone loss was largest within the first 40 days after transplantation and small during the second half of the first year after transplantation. The majority of patients showed vitamin D deficiency and secondary hyperparathyroidism. Bone formation was normal before and after transplantation, whereas bone resorption was dramatically increased before and after transplantation. Exposure to glucocorticoids was associated with higher bone loss at spine and femoral neck but not at the total body compartment. Our data demonstrate rapid bone loss in patients undergoing transplantation of hematopoietic stem cells. Bone turnover is characterized by biochemical uncoupling of bone resorption and bone formation, changes interestingly pre-existing before transplantation. The observed alterations in bone mass and metabolism emphasize the importance of clinical trials with antiresorptive agents to prevent and treat post-transplantation osteoporosis in this group of patients. Received: 30 March 1999 / Accepted: 10 October 1999  相似文献   

12.
Bone loss and osteoporotic fractures are common in cardiac transplant recipients. To compare two prophylactic medical regimens after heart transplantation, 26 consecutive heart transplant recipients were randomized to receive either continuous oral calcitriol (0.5 μg/day) combined with nasal salmon calcitonin (200 U/day) for the first 3 months (group A) or intermittent intravenous pamidronate (0.5 mg/kg body weight) every third month (group B). Bone mineral density (BMD) and biochemical indices of bone turnover were measured at baseline and 3, 6, 12, and 18 months after transplantation. The mean pretransplant BMD, measured by dual energy X-ray absorptiometry (DXA) was significantly lower in the patients compared with age-matched healthy controls. During the first year of treatment, rates of bone loss at the lumbar spine and femoral neck were slightly but significantly slower in the patients treated with pamidronate, but there was no longer a significant difference between the two groups after 18 months of heart transplantation. Irrespective of the mode of osteoporosis prevention, osteocalcin levels increased whereas urinary deoxypyridinoline decreased after transplantation, and significant bone loss was observed in both treatment groups. We found no relationship between initial BMD, markers of bone turnover, cumulative glucocorticoid dose, or cyclosporine levels and the rate of bone loss after cardiac transplantation. In summary, we found that the rapid and severe bone loss following heart transplantation could be attenuated by two preventive measures, pamidronate or calcitriol with calcitonin. Received: 26 December 1997 / Accepted: 10 February 2000  相似文献   

13.
After liver transplantation there is a high incidence of fractures, with important rates of bone loss during the first months. However, the long-term evolution of bone mass and metabolism parameters have been scarcely studied. In order to determine the incidence and risk factors involved in the development of skeletal fractures and to analyze the long-term evolution of bone mass, bone turnover and hormonal status after liver transplantation, a 3-year prospective study was performed in 45 patients following liver transplantation. Serum osteocalcin, parathyroid hormone (PTH), 25-hydroxyvitamin D (25-OH D) and testosterone levels (men), and bone mass at the lumbar spine and femur were measured before and sequentially at different time points during 3 years. Spinal X-rays were obtained during the first year. Histomorphometric analysis of bone biopsies obtained in 24 patients within the first 12 hours after surgery and 6 months after transplantation was performed. Fifteen patients (33%) developed fractures after liver transplantation, and pre- transplant risk factors for fractures were age and low bone mass (odd”s ratio for osteoporosis, 95% confidence interval: 5.69, 1.32–24.53). Serum PTH, osteocalcin, 25-OH D, testosterone and creatinine levels increased after transplantation. Moreover, PTH correlated with creatinine and osteocalcin values. Bone mass decreased during the first 6 months and reached baseline values at the lumbar spine the second year, with posterior significant recovery at the femoral neck. Long term evolution of femoral neck BMD correlated with PTH levels. Six months after transplantation bone histomorphometric data showed an increase in bone formation parameters. After liver transplantation there is a high incidence of fractures, specially in elderly patients and those with osteoporosis. Bone mass decreased in the short-term period and improved, initially at the lumbar spine and later at the femur, according to histomorphometric evidences of an increase in bone formation. The increase in creatinine values induces a secondary hyperparathyroidism that influences the changes in femoral bone mass. Treatment of osteoporosis shortly after liver transplantation may be important in the prevention of bone fractures, particularly in patients with low bone mass. Received: June 2000 / Accepted: November 2000  相似文献   

14.
Bone loss characterizes both primary hyperparathyroidism (PHPT) and osteoporosis (OP) but with a different histologic pattern, and this could partially explain the different fracture incidence in these two populations. Quantitative ultrasound (QUS), influenced by bone structural parameters other than bone mineral density (BMD), could evidence these differences, opening new perspectives in the evaluation of patients with metabolic bone diseases. The aim of the present study was to investigate the usefulness of QUS graphic trace parameters, assessed at the phalanx, in discriminating between PHPT bone disease and osteoporosis. We studied 34 patients with PHPT (mean age 59.7 ± 12.7 years), 35 patients with OP (mean age 60.6 ± 7.1 years) and 34 healthy subjects as controls (mean age 59.1 ± 9.4 years). In all subjects QUS measurements were performed at the phalanx with a Bone Profiler (IGEA, Italy), obtaining the amplitude-dependent speed of sound (AD-SoS), fast wave amplitude (FWA), signal dynamic (SDy), bone transmission time (BTT) and ultrasound bone profile index (UBPI). Moreover, serum calcium, phosphorus, parathyroid hormone (PTH), bone isoenzyme of alkaline phosphatase (B-ALP) and ionized calcium were measured in all subjects in the morning under fasting conditions. In PHPT patients BTT was correlated with PTH, ionized calcium and B-ALP levels (r=–0.47, –0.57 and –0.44, respectively; p <0.01), whereas FWA, SDy and UBPI correlated only with B-ALP (r=–0.43, –0.46 and –0.50, respectively; p <0.01). Moreover, FWA, SDY and UBPI were significantly (p<0.01) lower and BTT significantly (p<0.001) higher in OP than in PHPT patients. UBPI, BTT, FWA and the BTT/FWA ratio, but not SDy, were able to discriminate between the two groups (area under the curve =0.66, 0.69, 0.67 and 0.81, respectively).  Our findings show that ultrasound signal parameters are differently influenced by bone changes characterizing primary hyperparathyroidism or osteoporosis. This suggests that the QUS signal could be a useful instrument in discriminating and studying some of the bone alterations typical of metabolic bone diseases. Received: 15 February 2001 / Accepted: 27 August 2001  相似文献   

15.
The aim of this study was to evaluate the effect of intermittent calcitonin on femoral bone quality in adult ewes from the time of ovariectomy. Six months after the start of the experiment, bone density measurements and mechanical testing (torsion and resonant frequency analysis of the diaphysis and compression of an excised trabecular bone cylinder from the femoral neck) were performed in sham-control and ovariectomized (OVX) ewes treated with placebo or salmon calcitonin (50 or 100 units, 3 times/week). Crystallinity of bone was evaluated by measuring X-ray diffraction line broadening. After OVX, a nonsignificant bone loss was found at all measured sites in the femur (−3 to −9%) together with a decreased biomechanical competence in the trabecular bone (compressive strain −28%, P < 0.05). Treatment with salmon calcitonin, 50 or 100 IU subcutaneously three times a week from the time of ovariectomy, resulted in a significant dose-dependent preservation of bone strength in the trabecular bone of the femoral neck compared with OVX. No adverse effects of calcitonin were observed on bone crystal composition as assessed by diffractiometry. We conclude that in adult ewes intermittent calcitonin treatment from the time of OVX was associated with a significant preservation of cancellous bone strength and strain in trabecular bone of the femoral neck, without affecting crystalline properties of bone. Received: 20 October 1995 / Accepted: 19 February 1996  相似文献   

16.
The symmetry and effect of side dominance on the bone mineral density (BMD) of proximal femur was evaluated in 266 normal Chinese women with a dual photon absorptiometer (DPA, Norland 2600). The BMDs of the femoral neck, trochanter, and Ward's triangle at the proximal femur in the dominant leg (BMDd) were compared with those of the nondominant side (BMDn). The linear regression of BMDd and BMDn of the corresponding regions at the proximal femur showed a good correlation (r = 0.893–0.941, SEE = 0.052–0.062 g/cm2). The paired difference of proximal femoral BMD was −0.002 ± 0.062 g/cm2 for the femoral neck, 0.003 ± 0.054 g/cm2 for the trochanter, and 0.008 ± 0.062 g/cm2 for the Ward's triangle. The ratio of asymmetry for femoral neck BMD was mean ± SD =−0.4 ± 7.8%, for trochanter 0.6 ± 8.1%, and for the Ward's triangle 1.3 ± 9.7%. Both paired difference and ratio of asymmetry between BMDd and BMDn were approximately normally distributed, with a mean ± 2 SD ranging from −0.126 to 0.122 g/cm2 for paired difference and −16.0% to 15.2% for the ratio of asymmetry in the femoral neck. These data revealed that dominance had little effect on the proximal femur BMDs. However, the wide range of paired difference and ratio of asymmetry of the proximal femur BMD in the normal individuals should be considered in the interpretation of the proximal femoral BMD. Received: 26 July 1996 / Accepted: 23 April 1997  相似文献   

17.
In the present study, we assessed the ability of increasing doses of intranasal calcitonin to suppress urinary deoxypyridinoline cross-link (DPD), a specific biochemical marker of bone resorption, in early postmenopausal women. Subjects consisted of 30 healthy Thai women within 5 years of postmenopause, randomly assigned to 50, 100, or 200 IU of intranasal calcitonin 5 days/week for 3 months. Calcium supplementation by calcium carbonate capsules at 750 mg of elemental calcium per day was given to all subjects. Twenty four-hour urine for DPD and creatinine assays was collected at baseline, 1 month, and 3 months after treatment. All DPD values were corrected with urinary creatinine before analyses. Data were expressed as mean ± SEM. DPD decreased significantly 1 month after intranasal calcitonin treatment (P < 0.01). However, at 3 months, DPD increased when compared with the values at 1 month (P < 0.01), suggesting that there may be a reduction in the suppression of bone resorption after prolonged calcitonin therapy. Using a stepwise multiple regression model to address whether dosage and DPD at baseline influence the response to intranasal calcitonin, it was found that DPD suppression after intranasal calcitonin was not related to dosage but was strongly associated with baseline DPD (P < 0.0001). Suppression of bone resorption in early postmenopausal women by intranasal calcitonin is determined more by the state of bone turnover at baseline than the dosage of calcitonin. Received: 10 March 1997 / Accepted: 14 November 1997  相似文献   

18.
Long-term use of high-dose corticosteroids often results in bone loss, which may lead to osteoporosis-related fractures. This was a multicenter, double-blind study in which 290 ambulatory men and women receiving high-dose oral corticosteroid therapy (prednisone > or = 7.5 mg/day or equivalent) for 6 or more months were randomized to receive placebo, risedronate 2.5 mg/day, or risedronate 5 mg/day for 12 months. All patients received calcium 1 g and vitamin D 400 IU daily. The primary endpoint was lumbar spine bone mineral density (BMD) at month 12. Additional measurements included BMD at the femoral neck and trochanter and the incidence of vertebral fractures. Overall, there were statistically significant treatment effects on BMD at 12 months at the lumbar spine (p < 0.001), femoral neck (p = 0.004), and trochanter (p = 0.010). Risedronate 5 mg increased BMD at 12 months by a mean (SEM) of 2.9% (0.49%) at the lumbar spine, 1.8% (0.46%) at the femoral neck, and 2.4% (0.54%) at the trochanter, whereas BMD was maintained only in the control group. Although not powered to show fracture efficacy, we observed a reduction in the incidence of vertebral fractures of 70% in the combined risedronate treatment groups, relative to placebo (p = 0.042). Risedronate was well tolerated, had a good safety profile, and was not associated with gastrointestinal adverse events. We conclude that risedronate increases BMD and potentially reduces the incidence of vertebral fractures in patients with corticosteroid-induced osteoporosis.  相似文献   

19.
Diurnal Variation of Bone Mineral Turnover in Elderly Men and Women   总被引:5,自引:0,他引:5  
The diurnal variation of markers of bone mineral metabolism have been documented in pre- and early postmenopausal women. Such rhythms have clinical implications for timing of sample collection and assessment of therapeutic intervention. To examine the diurnal variation of bone turnover in the elderly, we examined markers of bone formation [serum osteocalcin (OC) and bone-specific alkaline phosphatase (B-ALP)]; a marker of bone resorption (urinary N-telopeptide cross-linked collagen type 1 [NTX]); and serum calcium and parathyroid hormone (PTH) over 24 hours. Subjects were healthy community-dwelling elderly who were on no medications known to significantly alter bone mineral metabolism. Subjects included 14 women [74 ± 6 years (mean ± SD)] and 14 men (80 ± 5 years). Over the 24-hour sampling period, mean serum OC, B-ALP, and calcium values were similar in elderly men and women. However, mean serum PTH was significantly higher in elderly men compared with women (P < 0.05). The magnitude of the diurnal variation of urinary NTX was significantly higher in women compared with men (P < 0.05). There was a significant diurnal variation for serum OC, B-ALP, calcium, PTH, and urinary NTX in both elderly men and women. The magnitude of the diurnal variation was approximately 10–20% of mean value for OC and B-ALP, 30% for PTH, and up to 40% for urinary NTX. We conclude that there is significant diurnal variation in the markers of bone mineral metabolism for elderly men and women. The peak value, which on average would be 20% higher than the mean value for urinary NTX, highlights the importance of the timing of sample collection for appropriate interpretation of therapeutic response. In addition, gender-related differences, including relatively higher levels of serum PTH and lower levels of urinary NTX in elderly men, may help explain differences in rates of bone loss in this age group. Received: 21 June 1996 / Accepted: 18 October 1996  相似文献   

20.
The effect of oral pamidronate on bone mineral density and its adverse effect profile was investigated by a double-masked placebo-controlled study of 122 patients aged 55–75 years with established vertebral osteoporosis. Patients on active therapy received disodium pamidronate 300 mg/day (group A) for 4 weeks every 16 weeks, 150 mg/day (group B) for 4 weeks every 8 weeks or placebo (group C). All patients additionally received 500 mg of calcium and 400 IU vitamin D daily. Dual-energy X-ray absorptiometry measurements of the spine, hip, forearm and total body were performed at baseline and 6-monthly for 2 years using a Hologic QDR 1000 device at two sites. Serum osteocalcin and urinary deoxypyridinoline were measured at the above visits and at 3 months. The percentage change (SEM) in spine bone mineral density (BMD) at 2 years based on intention-to-treat analysis was 4.64 (1.01) in group A, 6.10 (0.87) in group B and 1.13 (1.32) in group C. Analysis of variance showed significant increases in group A and B compared with placebo (p<0.01). There were also significant rises in femoral neck BMD for group A (p = 0.005), trochanter BMD for groups A and B (p<0.01) and total-body BMD for groups A and B (p<0.001). There was a significant reduction in serum osteocalcin and urinary deoxypyridinoline for groups A and B (p<0.01). There was an excess of gastrointestinal side-effects in the treated groups, particularly group A. We conclude that intermittent pamidronate therapy can prevent bone loss at both the lumbar spine and femoral neck in patients with established vertebral osteoporosis, although due to gastrointestinal side-effects the 300 mg dose in particular does not appear suitable for clinical usage. Received: 12 January 1999 / Accepted: 30 August 1999  相似文献   

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