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1.
Subjects exposed to environmental tobacco smoke have been found to be at increased risk for several health problems. Whether exposure to passive tobacco smoke is associated with reduced bone mineral density (BMD) is unknown. In order to examine this, we measured BMD in 154 healthy premenopausal women (age range 40–45 years). BMD of the total hip, femoral neck, lumbar spine and total body was measured by dual-energy X-ray absorptiometry (DXA). Data were collected on exposure to household tobacco smoke from age 10 years to the present as well as on other lifestyle factors related to bone mass. We found that 67.5% of the subjects had a history of household tobacco smoke exposure. Subjects exposed to household tobacco smoke had a mean adjusted BMD that was significantly lower at the total hip (p= 0.021) and femoral neck (p= 0.018) compared with subjects who were not exposed. In addition, duration of household tobacco smoke exposure was negatively associated with BMD at the total hip (p = 0.010), femoral neck (p= 0.004), lumbar spine (p = 0.037) and total body (p = 0.031). Subjects exposed to household tobacco smoke for 15 years or more had mean adjusted BMD that was 4% lower at the total body, and more than 8% lower at the total hip, femoral neck and lumbar spine, compared with subjects who were not exposed. In conclusion, household tobacco smoke exposure during adolescence and young adulthood was found to be negatively associated with BMD at the total hip and femoral neck, and duration of exposure was negatively associated with BMD at the total hip, femoral neck, lumbar spine and total body in premenopausal women. Received: 17 December 2001 / Accepted: 16 February 2002  相似文献   

2.
Bone Density in an Immigrant Population from Southeast Asia   总被引:9,自引:0,他引:9  
The epidemiology of bone loss in populations of Asian heritage is still poorly known. This study compared the skeletal status of a convenience sample of 396 Southeast Asian immigrants (172 Vietnamese, 171 Cambodians and 53 Laotians) residing in Rochester, Minnesota in 1997 with 684 white subjects previously recruited from an age-stratified random sample of community residents. Areal bone mineral density (BMD, g/cm2) and volumetric bone mineral apparent density (BMAD, g/cm3) were determined for lumbar spine and proximal femur using the Hologic QDR 2000 instrument for the white population and the QDR 4500 for Southeast Asian subjects; the machines were cross-calibrated from data on 20 volunteers. Lumbar spine BMD was 7% higher in white than Southeast Asian women ( p < 0.001), and similar results were observed for the femoral neck; lumbar spine BMD was 12% higher in white than nonwhite men ( p < 0.001). Race-specific discrepancies were reduced by calculating BMAD: for premenopausal women, lumbar spine and femoral neck differences between whites and Southeast Asians were eliminated; for postmenopausal women the lumbar spine differences persisted ( p < 0.0001), while femoral neck BMAD was actually higher for Southeast Asians. There were no race-specific differences in femoral neck BMAD among men of any age ( p= 0.312), but lumbar spine BMAD was less for younger ( p= 0.042) but not older ( p= 0.693) Southeast Asian men. There were differences among the Southeast Asian subgroups, but no clear pattern emerged. Predictors of lumbar spine BMAD in Southeast Asian women were age ( p < 0.001), weight ( p= 0.015) and gravidity ( p= 0.037). Even after adjusting for bone size using BMAD, 32% and 9% of Southeast Asian women and men, respectively, would be considered to have osteoporosis at the femoral neck and 25% and 4%, respectively, at the lumbar spine. These findings indicate a need for culturally sensitive educational interventions for Southeast Asians and for physicians to pursue diagnosis and treatment to prevent osteoporosis-related disabilities in this population. Received: 12 October 2000 / Accepted: 15 February 2001  相似文献   

3.
The aim of this study was to determine possible associations between bone mineral density (BMD), 25-hydroxyvitamin D (25(OH)D) and intact parathyroid hormone (PTH). In a retrospective study we examined the case notes of free-living postmenopausal women living in our city (34° S). We also report a low prevalence of vitamin D deficiency (25(OH)D <25 nmol/l, 5.6%) and of secondary hyperparathyroidism (intact PTH >65 pg/ml, 7.5%). Age was correlated with BMD at the lumbar spine (r=−0.25, p = 0.00038) and femoral neck (r=−0.252, p = 0.0003). Body mass index (BMI) was correlated with BMD at the femoral neck (r= 0.177, p = 0.021) but not at the lumbar spine. 25(OH)D was positively correlated with BMD at the femoral neck (r = 0.149, p=0.036) but not at the lumbar spine. PTH was positively correlated with age (r= 0.279, p = 0.012) and negatively correlated with 25(OH)D (r=−0.322, p = 0.0036). PTH was also negatively correlated with BMD at the lumbar spine (r=−0.258, p=0.02) and the femoral neck (r=−0.282, p = 0.011). Forward stepwise multiple regression showed that BMI, age and 25(OH)D made significant contributions to BMD at the femoral neck. PTH also showed a significant contribution to BMD at both sites. In conclusion, weak correlations found between PTH and 25(OH)D and BMD suggest these biochemical variables, among other factors, contribute to lumbar spine and femoral neck BMD. Received: 19 February 2000 / Accepted: 20 June 2000  相似文献   

4.
In two recent case–control studies premature greying of the hair was associated with a lowering of bone mineral density (BMD) and osteopenia, suggesting that this might be a clinically useful risk marker for osteoporosis. We report a further re-examination of this proposal in 52 prematurely grey-haired women from East Yorkshire who responded to an advertisement inviting them for bone densitometry. Thirty-five had no clinical or drug history that could influence bone density. All were Caucasian with a mean age of 52.8 years. In the group as a whole the mean BMD values at the lumbar spine and femoral neck were no different from those of a young adult, but there was a trend toward a greater than average BMD than that of the local age-matched population (p= 0.097 and 0.218, respectively). Twenty women were premenopausal, with an average age of 45.3 years. Mean BMD values at the lumbar spine and femoral neck in this group were no different from those of young adults. There was, however, a trend toward a BMD greater than that of the local age-matched population at the femoral neck (p= 0.117). Fifteen women were postmenopausal with an average age of 62.9 years and an average age at menopause of 51.1 years. Mean BMD values at both the lumbar spine and femoral neck in this group were lower than those of young adults, but no different from those of the local age-matched population. In conclusion, our group of prematurely grey-haired women had average BMD for their age, and we are therefore unable to support the proposed clinical usefulness of premature greying as a risk marker for osteoporosis. Received: 1 December 1998 / Accepted: 11 March 1999  相似文献   

5.
We assessed the clinical usefulness of bone density measurements at the os calcis as a screening tool to identify patients with low bone density at the lumbar spine and femoral neck. Bone mineral density (BMD) was recorded in 443 women (mean age 60 years) referred to a bone densitometry service. Measurements were made at the lumbar spine and femoral neck using a Lunar DPXL and at the right os calcis using a Peripheral Instantaneous X-ray Imaging (PIXI) dual-energy X-ray absorptiometry system. Average T-scores derived using the manufacturer”s data were: 1.59 for the lumbar spine, −1.41 for the femoral neck and −0.87 for the os calcis. The prevalence of osteoporosis using WHO criteria (T-scores of −2.5 or less) was 36% for the lumbar spine or femoral neck but only 9.7% for the os calcis. BMD of the os calcis correlated with that at the lumbar spine (r= 0.69, p<0.001) and femoral neck (r= 0.67, p<0.001). The area under the receiver operator characteristics curve was 0.836 (standard error 0.020) for the os calcis related to osteoporosis at the lumbar spine or femoral neck. Optimal accuracy was obtained at a T-score of ≤−1.3 (BMD 0.39 g/cm2) when the sensitivity was 69.6% (95% confidence interval 65.3, 73.9%) and specificity 82.6% (95% confidence interval 79.1, 86.1%). However, the probability of diagnosing low bone density from a given BMD at the os calcis varied by age and site scanned. Accordingly, for informing management strategies, the choice of a single cutoff BMD at the os calcis may not be appropriate and several thresholds may be adopted based on age, the site of interest (lumbar spine or femoral neck) and consideration of associated clinical features. Thus, the use of heel bone density scanners could reduce the number of axial bone density measurements required. The advantages of portability, low cost and shorter scan times should reduce the cost of detection and provide a greater opportunity for identification of women at risk of fracture. Received: 18 June 1999 / Accepted: 30 March 2000  相似文献   

6.
Bone mineral density (BMD), the major determinant of fracture risk, is under strong genetic control. Although polymorphisms of the vitamin D receptor (VDR) gene have been suggested to account for some of the genetic variation in bone mass, the influence of VDR genotypes on osteoporosis remains controversial. Previous published studies have focused mainly on women, but the pattern of response in men has not been determined. Using the BsmI restriction enzyme, we studied the influence of the different VDR genotypes on bone mass, bone loss and the prevalence of vertebral fractures in a population-based sample of both sexes (n = 326). BMD was measured at the lumbar spine and femoral neck, with a 4-year interval, using dual-energy X-ray absorptiometry. Vertebral fractures were assessed by two lateral radiographs at the beginning and end of the study. The prevalence of the three possible VDR genotypes was similar to those in other Caucasian populations and no differences were found between men and women. Women with the favorable bb genotype showed significantly higher BMD values at the lumbar spine and femoral neck, and a positive rate of BMD change at the femoral neck compared with women with the BB and Bb genotypes. Moreover, women with the bb genotype showed a trend toward a lower prevalence and incidence of vertebral fractures (p= 0.07). We have not found any differences between VDR genotypes in men. In conclusion, VDR gene polymorphisms are related to bone mass and bone loss in women; also a trend in the prevalence of vertebral fractures was observed in postmenopausal women but not in men. Received: 8 June 1998 / Accepted: 7 December 1998  相似文献   

7.
Alendronate significantly increases bone mass and reduces hip and spine fractures in postmenopausal women. To determine whether forearm densitometry could be used to monitor the efficacy of alendronate, we examined changes in bone mineral density (BMD) at the forearm (one-third distal, mid-distal, ultradistal radius) versus changes at the hip (femoral neck, total hip) and spine (posteroanterior and lateral) in a double-masked, randomized, placebo-controlled clinical trial of 120 elderly women (mean age 70 ± 4 years) treated with alendronate for 2.5 years. We found that among women in the treatment group, BMD increased by 4.0–12.2% at the hip and spine sites (all p<0.001), whereas BMD increased only nominally at the one-third distal radius (1.3%, p<0.001) and mid-radius (0.8%, p<0.05), and remained stable at the ultradistal radius. At baseline, forearm BMD correlated with that of the hip (r= 0.55–0.64, p<0.001), femoral neck (r= 0.54–0.61, p<0.001) and posteroanterior spine (r= 0.56–0.63, p<0.001). Changes in radial BMD after 1 year of therapy were not correlated with changes in hip and spine BMD after 2.5 years of therapy. In contrast, short-term changes in total hip and spine BMD were generally positively associated with long-term changes in total hip, femoral neck and spine BMD (r= 0.30–0.71, p<0.05). Furthermore, long-term BMD changes at the forearm did not correlate with long-term hip and spine BMD changes, in contrast to the moderate correlations seen between spine and hip BMD at 2.5 years (r= 0.38–0.45, p<0.01). We conclude that neither short- nor long-term changes in forearm BMD predict long-term changes in overall BMD for elderly women on alendronate therapy, suggesting that measurements of clinically relevant central sites (hip and spine) are necessary to assess therapeutic efficacy. Received: 18 February 1999 / Accepted: 20 May 1999  相似文献   

8.
Variations in Bone Density among Persons of African Heritage   总被引:3,自引:0,他引:3  
The epidemiology of bone loss in populations of African heritage is still poorly known. We compared a convenience sample of 47 African-American (AA) residents of Rochester, Minnesota (32 women, 15 men) and 66 recent immigrants from Somalia (all women) with 684 white subjects (349 women, 335 men) previously recruited from an age-stratified random sample of community residents. Areal bone mineral density (BMD, g/cm2) and volumetric bone mineral apparent density (BMAD, g/cm3) were determined for lumbar spine and proximal femur using the Hologic QDR 2000 for white subjects and the QDR 4500 for the others; the instruments were cross-calibrated from data on 20 volunteers. Lumbar spine BMD was 18% higher in AA (p<0.001) and 4% lower in Somali (p= 0.147) than white women. Femoral neck BMD was 27% higher in AA women but also 11% greater in Somali women (both p<0.001) compared with whites. Lumbar spine BMD was 6% higher (p= 0.132) and femoral neck BMD 21% higher (p<0.001) in AA than white men. No Somali men were studied. After correcting for bone size differences, both lumbar spine (p<0.01) and femoral neck BMAD (p<0.001) were greater for Somali than white women, but the difference between Somali and AA women persisted. Lumbar spine and femoral neck BMAD values also remained significantly greater for AA women (both p<0.001) and men (p<0.05; p<0.001) compared with whites. Weight was associated with BMAD at both skeletal sites in all groups, but adjustment for differences in weight did not reduce the discrepancy in BMAD values between Somali and AA women or between the latter group and whites. This heterogeneity among different ethnic groups of African heritage may provide an opportunity for research to better explain race-specific differences in bone metabolism. Received: 4 September 2001 / Accepted: 11 January 2002  相似文献   

9.
To determine the physiologic and habitual factors that may modulate changes in bone mineral density (BMD) postpartum, dual-energy X-ray absorptiometry was performed at the lumbar spine, right femoral neck and dominant distal radius immediately after delivery, after resumption of menses, and 1 year thereafter in a cohort of 41 healthy postpartum Finnish women aged 31.5 (SD 4.6) years. Mean durations of lactation and postpartum amenorrhea (PPA) were 7.7 (3.7) and 5.9 (2.9) months, respectively. After PPA, significant bone losses of 2%–4% were observed at the lumbar spine and femoral neck. Duration of PPA and different lactational variables explained (adjusted R 2) from 21% to 27% of the variability in changes in BMD during PPA. A recovery to postpregnancy BMD levels was observed at the lumbar spine; in contrast BMD at the femoral neck showed only a partial recovery. The duration of unsupplemented lactation was weakly (adjusted R 2= 0.13) associated with recovery at the lumbar spine, while a long duration of total lactation also showed a weak association (adjusted R 2= 0.02) with delayed recovery at the femoral neck. In conclusion, a systematic bone loss occurs during PPA, and after resumption of menstruation BMD recovers despite continued lactation. However, the time of bony recovery back to postpregnancy level seems to be modulated slightly by lactation habits. It is obvious that the control of postpartum BMD changes is a multifactorial process that may be specific to the skeletal site of interest. Received: 7 June 1999 / Accepted: 5 January 2000  相似文献   

10.
The aim of the study was to investigate the effects of regular aerobic exercise training on bone mineral density (BMD) in middle-aged men. A population based sample of 140 men (53–62 years) was randomly assigned into the exercise and reference groups. BMD and apparent volumetric BMD (BMDvol) of the proximal femur and lumbar spine (dual-energy X-ray absorptiometry, DXA) and anthropomorphic measurements were performed at the randomization and 2 and up to 4 years later. The participation rate was 97% and 94% at the second and third BMD measurements, respectively. As another indication of excellent adherence and compliance, the cardiorespiratory fitness (aerobic threshold) increased by 13% in the exercise group. The 2% decrease in the reference group is regarded as an age-related change in cardiorespiratory fitness. Regardless of the group, there was no association between the increase in aerobic threshold and change in BMD. In the entire group, age-related bone loss was seen in the femoral neck BMD and BMDvol (p<0.01). BMD and BMDvol values increased with age in L2–L4 (p<0.004). An increased rate of bone loss at the femoral neck was observed in men with a low energy-adjusted calcium intake (p = 0.003). Men who increased their alcohol intake during the intervention showed a decrease in the rate of bone loss at the femoral neck (p = 0.040). A decrease in body height associated with decreased total femoral BMD (r= 0.19, p = 0.04) and the change in body height was a predictor of bone loss in the femoral neck (β= 0.201). Long-term regular aerobic physical activity in middle-aged men had no effect on the age-related loss of femoral BMD. On the other hand, possible structural alterations, which are also essential for the mechanical strength of bone, can not be detected by the DXA measurements used in this study. The increase seen in lumbar BMD reflects age-related changes in the spine, thus making it an unreliable site for BMD follow-up in men. Received: August 2000 / Accepted: November 2000  相似文献   

11.
The aim of the study was to evaluate whether computed digital absorptiometry (CDA) of the hand might be a useful screening technique for identifying patients with postmenopausal osteoporosis and to compare the results of CDA with those of dual-energy X-ray absorptiometry (DXA) of the lumbar spine and femoral neck. We studied 230 postmenopausal women (mean age 58.4 ± 7.9 years). For CDA, bone mineral density (BMD) was measured with an AccuDEXA Schick densitometer in the third middle phalanx of the nondominant hand. For DXA, BMD of the lumbar spine and upper femur was assessed using a DXA Hologic QDR-1000 densitometer. We did a comparative analysis (ANOVA) and linear correlation tests. Sensitivity and specificity of CDA and receiver operating characteristic (ROC) curves for the diagnosis of osteoporosis were calculated. The mean BMD with CDA was 0.445 ± 0.084 (T-score: −1.27 ± 1.29). The mean BMD (g/cm2) with DXA at the lumbar spine was 0.877 ± 0.166 (T-score: −1.52 ± 1.59) and 0.708 ± 0.127 at the femoral neck (T-score: −1.12 ± 1.25). BMD at the lumbar spine and femoral neck correlated positively with CDA of the hand (r= 0.66 and r= 0.65 respectively, p<0.001). When using as cut-off a T-score of −2.5, according to WHO criteria, 76 women (33%) had osteoporosis of the lumbar spine and/or femoral neck with DXA and 42 (18%) with CDA (p<0.001). The kappa score for osteoporosis was 0.33 for CDA versus spinal DXA and 0.35 for CDA versus femoral DXA. With the cut-off level used, sensitivity and specificity of CDA in detecting osteoporosis at the lumbar spine were 0.39 and 0.90, respectively; sensitivity and specificity of CDA in identifying osteoporosis at the femoral neck were 0.58 and 0.87, respectively. The positive predictive value of CDA for osteoporosis was 69% and the negative predictive value was 75%. The area under the ROC curve for osteoporosis was 0.822 ± 0.028. We conclude that: (a) CDA assessment has a moderate correlation with BMD measured by DXA at the lumbar spine and femoral neck; (b) CDA has a low sensitivity for the diagnosis of osteoporosis compared with spinal and femoral DXA; and (c) predictive values for osteoporosis at both the lumbar spine and femoral neck are acceptable. Received: September 2000 / Accepted: January 2001  相似文献   

12.
Osteoporosis is a common disorder with a strong genetic component. Our aim was to evaluate the correlation of the vitamin D receptor gene intron 8 BsmI polymorphism with bone mineral density (BMD) and their relationship to osteoporosis. We determined the vitamin D receptor gene intron 8 BsmI polymorphism using polymerase chain reaction-based restriction analysis in 171 postmenopausal Chinese women in Taiwan. The polymorphism was detected using the restriction enzyme BsmI, where the B allele indicated absence of the cuttable site and the b allele its presence. BMD of the lumbar spine and proximal femur were measured using dual-energy X-ray absorptiometry. The allelic frequencies for postmenopausal Chinese women in Taiwan were 12.3% for B and 87.7% for b in BsmI restriction fragment length polymorphisms. The prevalence of each genotype in the study population was: 6.4% BB, 11.7% Bb and 81.9% bb. The three genotypic groups differed significantly in BMD at the lumbar spine and the femoral neck. These differences corresponded to significant gene-dose effects at the lumbar spine and femoral neck (p<0.001 for both sites). The relative risk for the development of osteoporosis was about 2–3 times as great as that predicted by the differences between genotypes in BMD, and remained significant even after adjustment for age, height and weight. The vitamin D receptor gene intron 8 BsmI polymorphism is associated with reduced BMD and predisposes women to osteoporosis. Received: 21 February 2001 / Accepted: 31 May 2001  相似文献   

13.
Hormone replacement therapy (HRT) prevents postmenopausal bone loss and fractures. However, the occurrence of women with no bone response to HRT has not been widely examined. We identified the densitometric nonresponders to long-term HRT and investigated some characteristics and biochemical variables as possible predictors of densitometric nonresponse in postmenopausal women. The study population was a subsample of the Kuopio Osteoporosis Study (n= 14.220). A total of 464 early postmenopausal women were randomized into four treatment groups: (1) HRT (sequential combination of 2 mg estradiol valerate and 1 mg cyproterone acetate); (2) vitamin D3; (3) HRT + Vitamin D3 combined; and (4) placebo. In this study, the data from HRT and placebo groups were analyzed. Lumbar (L2–4) and femoral neck bone mineral density (BMD) were determined by dual-energy X-ray absorptiometry (DXA) at baseline and after 5 years of treatment. A densitometric nonresponder was defined as a woman whose 5-year BMD change was similar to the mean BMD change (+ 95% CI) of the placebo group or worse. Altogether, 74 women in the HRT group and 104 women in the placebo group complied with the treatment. According to spinal BMD analysis, 11% of the women were classified as densitometric nonresponders; the corresponding proportion for femoral BMD analysis was 26%. Both smoking (p= 0.003) and low body weight (p= 0.028) were significant risk factors for densitometric nonresponse to HRT. After 6 months of treatment the densitometric nonresponders (hip) had a significantly higher mean serum follicle stimulating hormone (FSH) level (p= 0.038) and lower increases in serum estradiol levels (p= 0.006) than the densitometric responders. The mean changes in serum FSH and alkaline phosphatase levels were significantly lower among the densitometric nonresponders (spine) than responders (p= 0.043 and 0.017, respectively). In conclusion, this prospective study shows that especially current smokers and women with low body weight are at increased risk of poor bone response to HRT. Repeated serum FSH, estradiol and alkaline phosphatase measurements during the first months of long-term HRT may be helpful in identifying the women with no bone response to HRT. Received: 29 January 1999 / Accepted: 2 August 1999  相似文献   

14.
The objective of this study was to assess the long-term effects of tibolone 2.5 mg daily (Livial1; Organon) on bone mineral density in recently postmenopausal women. An 8-year, open, nonrandomized, prospective study was designed to compare the effects of tibolone 2.5 mg daily (n= 59) with an untreated control group (n= 51). The subjects of this study were 110 recently postmenopausal women (6–36 months since last menstrual period). The main outcome measures were bone mineral density of the spine and femur, measured by dual-energy X-ray absorptiometry, and assessment of biochemical markers of bone metabolism. After 8 years of tibolone use, the mean (± SEM) increase in bone mineral density compared with baseline was 4.1%± 0.8% (p<0.0001) in the spine and 4.6%± 1.8% (p= 0.015) in the femoral neck. Over the same period, bone mineral density in the control group decreased in the spine by –7.5%± 1.1%, (p<0.0001) and in the femur by –6.7%± 1.2% (p<0.0001). The bone resorption marker, calcium/creatinine ratio, decreased in the tibolone group but not in the control group. Serum bone formation markers decreased (alkaline phosphatase) or stayed approximately the same (osteocalcin) in the tibolone group. Adherence was high, with 58% (34 of 59) of the tibolone group continuing treatment for 8 years. We conclude that tibolone 2.5 mg daily prevents bone loss in the lumbar spine and femoral neck over 8 years and adherence to treatment is high. The greater bone density compared with untreated women would be expected to reduce the risk of bone fractures. Received: September 2000 / Accepted: December 2000  相似文献   

15.
Alendronate has been reported to increase bone mineral density (BMD) and reduce fracture risk in women with osteoporosis. As there are no proven safe and effective treatments available for men with osteoporosis, we compared the effects of alendronate (10 mg/day) on BMD, measured using dual-energy X-ray absorptiometry, in a 12-month prospective, controlled, open label study involving (i) men with primary (n= 23) or secondary osteoporosis (n= 18), (ii) postmenopausal women with primary (n= 18) or secondary (n= 21) osteoporosis, and (iii) 29 male and 14 female untreated controls matched by age, height and weight. The patients had one or more vertebral fractures and ranged in age from 34.6 to 85.1 years. BMD was detectably increased relative to baseline by 6 months, and increased by comparable amounts in males and females with primary or secondary osteoporosis. At 12 months, lumbar spine BMD was 5.4%± 1.1% to 7.0%± 2.2% higher in the treated groups compared with baseline and controls (p<0.05 to 0.0001). Trochanteric BMD increased by 2.6%± 1.5% and 3.7%± 1.7% in treated men with primary and secondary osteoporosis, respectively (p = 0.06 to 0.08), and by 3.9%± 1.3% in treated women with primary osteoporosis (p<0.01) after 12 months. No significant changes were detected at the femoral neck or Ward’s triangle. BMD remained unchanged in controls. We infer that alendronate has comparable incremental effects on BMD in men and women with primary and secondary osteoporosis within 12 months of treatment. The changes are in the order of 0.5 SD – effects associated with a clinically worthwhile reduction in fracture risk. The data provide room for optimism regarding the role of alendronate in the treatment of osteoporosis in men. Randomized, double-masked and placebo-controlled trials are needed to confirm these preliminary findings and demonstrate antifracture efficacy using vertebral and nonvertebral fracture rates as the primary endpoint. Received: 23 February 1999 / Accepted: 2 June 1999  相似文献   

16.
Recently a polymorphism was found in the human osteocalcin gene, and its association with bone mass was investigated in healthy postmenopausal Japanese women. The osteocalcin gene allelic variant HH was found to be overrepresented in women with osteopenia. The purpose of this study was to investigate whether the previously demonstrated polymorphism of the osteocalcin gene was related to bone mineral density (BMD; g/cm2) or osteopenia in a group of 97 healthy Caucasian adolescent females (aged 16.9 ± 1.2 years, mean ± SD). BMD of the left humerus, right femoral neck, lumbar spine and total body was measured using dual-energy X-ray absorptiometry. The relation between the allelic variants and bone density was analyzed as presence or absence of the H allele. Presence of the H allele was found to be related to a lower BMD of the humerus (0.97 vs 1.02, p = 0.03). There was also a strong tendency towards significance at the femoral neck (p = 0.06) and total body (p = 0.11). Using a multiple linear regression and including physical activity, weight, height and years since menarche, presence of the H allele was found to be an independent predictor of humerus BMD (β=−0.21, p<0.05) and femoral neck BMD (β=−0.23, p<0.01). Using logistic regression, presence of the H allele was also independently associated with a 4.5 times increased risk of osteopenia (p = 0.03) in the whole group. Osteopenia was defined as at least 1 SD lower bone density than the mean for the whole group of at least one of the BMD sites measured. We have demonstrated that the osteocalcin HindIII genotype is independently related to bone density in healthy adolescent females. The present study also suggests that presence of the H allele is predictive of osteopenia at an early age. Received: 31 January 2000 / Accepted: 25 April 2000  相似文献   

17.
An analysis of trabecular bone texture based on fractal mathematics, when applied to trabecular bone images on plain radiographs, can be considered as a reflection of trabecular bone microarchitecture. It has been shown to be able to distinguish postmenopausal osteoporosis cases from controls. This cross-sectional study was carried out to investigate the influence of age, time since menopause and hormone replacement therapy (HRT) on the fractal dimension of trabecular bone texture at the calcaneus in a sample of 537 healthy women. Fractal analysis of texture was performed on calcaneus radiographs and the result expressed as the Hmean parameter (H = 2–fractal dimension). Total hip, femoral neck and lumbar spine bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. There was a statistically significant Hmean parameter decrease with age (p<0.0001) but the degree of correlation was low (r=–0.2) compared with the correlation between age and BMD (r=–0.36 to –0.61 according to the BMD site). We found a weak but statistically significant correlation between time since menopause and Hmean (r=–0.14, p= 0.03) in the 241 postmenopausal women included in the study. Hmean was significantly lower in a group of postmenopausal women without HRT (n= 110) compared with a group of age-matched postmenopausal women with HRT (n = 110): respectively 0.683 ± 0.043 and 0.695 ± 0.038 (p= 0.03). In conclusion, this study suggests that there is a menopause- and age-related decrease in the Hmean parameter and that HRT interferes with the results of the fractal analysis of trabecular bone texture on calcaneus radiographs. Received: 2 March 2001 / Accepted: 2 October 2001  相似文献   

18.
Raloxifene, a selective estrogen receptor modulator (SERM), has been shown to improved bone mineral density (BMD) and serum lipid profiles in healthy postmenopausal women. The objective of this study was to examine the effects of raloxifene on BMD, biochemical markers of bone metabolism and serum lipids in postmenopausal women with low bone density or osteoporosis. This Phase II, multicenter, 24-month, double-masked study assessed the efficacy and safety of raloxifene in 129 postmenopausal women (mean age ± SD: 60.2 ± 6.7 years) with osteoporosis or low bone density (baseline mean lumbar spine BMD T-score: −2.8). Women were randomly assigned to one of three treatment groups: placebo, 60 mg/day raloxifene-HCl (RLX 60) or 150 mg/day raloxifene-HCl (RLX 150) and concomitantly received 1000 mg/day calcium and 300 U/day vitamin D3. At 24 months, BMD was significantly increased in the lumbar spine (+3.2%), femoral neck (+2.1%), trochanter (+2.7%) and total hip (+1.6%) in the RLX 60 group compared with the placebo group (p<0.05). The RLX 150 group had increases in BMD similar to those observed with RLX 60. A greater percentage of raloxifene-treated patients, compared with those receiving placebo, had increased BMD (p<0.05). Serum bone-specific alkaline phosphatase activity, serum osteocalcin, and urinary type I collagen:creatinine ratio were significantly decreased in the RLX-treated groups, compared with the placebo group (p<0.01). RLX 60 treatment significantly decreased serum levels of triglycerides, and total- and LDL-cholesterol levels (p<0.01). The rates of patient discontinuation and adverse events were not significantly different among groups. In this study, raloxifene increased bone density, decreased bone turnover, and improved the serum lipid profile with minimal adverse events, and may be a safe and effective treatment for postmenopausal women with osteoporosis or low bone density. Received: 26 December 1998 / Accepted: 31 March 1999  相似文献   

19.
This double-masked, placebo-controlled study was undertaken to determine the efficacy and safety of oral clodronate in the prevention of bone loss in early postmenopausal women with vertebral osteopenia. Altogether 610 women with a mean age of 53 years were recruited for the study. They were 1–5 years postmenopausal and their lumbar spine bone mineral density (BMD) was at least 1 standard deviation below the mean of premenopausal women (T-score ≤−1). The subjects were randomized into five study groups to receive either placebo, clodronate 65 mg, 400 mg or 800 mg daily, or intermittent clodronate in 3 month cycles with 400 mg daily for 15 days followed with no treatment for 75 days for 3 years. One hundred and eighty-seven of 509 women who completed the primary study continued in the extension study of 2 years in which previous placebo users were switched to clodronate 800 mg daily, while previous users of 400 mg or 800 mg of clodronate used either placebo or 800 mg of clodronate daily. In the primary study clodronate was administered in the evening, and in the extension 1 h before breakfast on an empty stomach. In the primary study mean changes in lumbar spine BMD were −3.4% in the placebo group and +0.4% in 800 mg clodronate group [difference between groups at 3 years 3.8% (95% CI 2.7% to 4.9%, p<0.0001)], and in the trochanter area BMD −1.1% in the placebo group, and + 0.4% in the 800 mg clodronate group [difference between groups at 3 years 1.5% (95% CI 0.05% to 2.9%)]. During the extension study mean changes in lumbar spine BMD were +1.5% in the clodronate group and −0.2 % in the placebo group [difference between groups 1.7% (CI 0.4% to 3.0%, p = 0.010)] and in trochanter BMD were +2.5% in the clodronate group and no change in the placebo group [difference between groups 2.1% (CI 0.3% to 3.9%, p = 0.007)]. No statistically significant differences between the placebo and 800 mg clodronate groups were found in the femoral neck BMD. In the primary study the urinary excretion of type I collagen aminoterminal telopeptide (NTX) decreased by 44% (p<0.0001 compared with placebo) and that of deoxypyridinoline by 18% (p<0.0001) in the clodronate 800 mg group. In the extension study urinary NTX decreased by 51% (p<0.0001) in those who were switched to 800 mg of clodronate and increased by 67% (p<0.0001) in those who stopped using that dose. There was no difference in the frequency of gastrointestinal complaints between clodronate- and placebo-treated patients in the primary study, but they were more common among women who received clodronate in the extension phase. Clodronate in daily doses of 400–800 mg caused a slight elevation of aminotransferase levels, usually within the reference range. In bone biopsies no defect in mineralization was found. In conclusion, clodronate in a daily dose of 800 mg prevents early postmenopausal bone loss at the sites of the skeleton in which cancellous bone predominates. It effectively reduces bone resorption and bone turnover rate. Antifracture efficacy of clodronate remains to be established by prospective, placebo-controlled trials. Received: 4 March 2002 / Accepted: 9 July 2002  相似文献   

20.
The purpose of this study was to test the ability of early changes in markers of bone turnover to predict subsequent changes in bone mineral density (BMD) induced by parathyroid hormone fragment, PTH (1–34), in postmenopausal osteoporotic women treated with estrogen and glucocorticoids. Forty-nine postmenopausal women with chronic, inflammatory diseases and BMD T-scores ≤–2.5 at the lumbar spine or femoral neck who were concurrently treated with estrogen ≥ 1 year and prednisone 5–20 mg/day for ≥ 1 year participated. Subjects were randomized to treatment with human PTH (1–34) 400 IU/day or to a control group for 1 year and followed for an additional year. Serum and urine were collected at baseline and 1, 3, 6, 9, 12, 18 and 24 months for measurement of bone alkaline phosphatase (BAP), osteocalcin (OC) and deoxypyridinoline (DPD). We constructed an Uncoupling Index (UI) from all three markers (UI = [Z BAP+Z OC]/2 –Z DPD, where the Z-score for each marker in each subject was calculated from the mean and standard deviation of the study population at baseline). BMD of the lumbar spine and hip was measured at baseline and every 6 months thereafter by dual-energy X-ray absorptiometry (DXA) and annually by quantitative computed tomography (QCT; spine only). BMD of the spine, but not hip (total, femoral neck or trochanter), and levels of all three markers increased significantly as a result of PTH treatment (p<0.01 compared with controls). The resorption response lagged behind that of formation as evidenced by a significant increase (p<0.05) in the UI for the first 9 months of treatment. The UI values and changes from baseline to 1, 3 and 6 months in BAP, OC and DPD were correlated with the 12- and 24-month changes in spine BMD measured both with QCT and with DXA (Spearman’s rank coefficients ≤0.76; p<0.05). Most PTH-treated subjects could be identified as biochemical responders by least significant change analysis. Following 1 month of therapy, BAP and OC identified 65% and 81% as responders, respectively. The responder rates were 79%, 79% and 75% for BAP, OC and DPD, respectively by 6 months. Responders exhibited a high level of diagnostic accuracy for predicting a gain in BMD (areas under the receiver operating characteristic curves exceeding 0.79 for QCT and 0.70 for DXA), but not the magnitude of the gain. These data suggest that serial bone marker measurements may be useful in identifying skeletal responders to an anabolic therapy, such as PTH, in estrogen-replete postmenopausal women with glucocorticoid-induced osteoporosis. Received: 27 July 1999 / Accepted: 2 November 1999  相似文献   

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