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Effects of levonorgestrel-releasing subdermal contraceptive implants on bone density and bone metabolism.

A prospective, randomized clinical trial observed the effects of Norplant long-term contraceptive implants and domestic implants similar to Norplant on bone mineral density and bone metabolism in female acceptors for 1 year. Bone mineral density (BMD) and bone mineral content (BMC) of lumbar 2-4 and proximal femur of 61 normal women of child-bearing age were measured by dual energy x-ray absorptiometry (DEXA) before and 12 months after implants insertion in both groups. BMD and BMC of lumbar 2-4 in both groups 12 months after implant insertion significantly increased (p < 0.01); with an average increase of 2.40% and 3.34%, respectively in the Norplant implant group, and 2.75% and 4.47%, respectively in the domestic implant group. Urine hydroxyproline and creatinine ratio (Hop/Cr) in the domestic implant group significantly decreased (p < 0.01). There was no significant differences in the effects on BMD and BMC of lumbar spine and femur and on bone metabolism between the two groups of contraceptive implants (p > 0.05). Levonorgestrel releasing contraceptive subdermal implants were not deleterious to the skeleton in women of child-bearing age. There was no significant effect on achieving maximum bone mass in young women.

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Effect of age on bone density and bone turnover in men.

OBJECTIVE: Little is known about the pattern of age-related bone loss in men, and although androgens are required for optimum bone mass it is not clear whether the fall in bone mass with age in men is related to falling androgens. DESIGN: Cross-sectional measurement of bone density, at five sites, and markers of bone resorption and formation in 147 normal volunteers aged 20-83 years. SUBJECTS: Healthy laboratory workers, hospital staff, their relatives, and husbands of women attending our osteoporosis clinic. MEASUREMENTS: Forearm density (fat corrected), spine L2-L4, femoral neck, Ward's triangle and trochanter density; serum procollagen I C-terminal extension peptide, osteocalcin, bone alkaline phosphatase and collagen I C-terminal telopeptide; fasting urine hydroxyproline/creatinine, pyridinoline/creatinine and deoxy-pyridinoline/creatinine; and free androgen index (FAI), measured as serum testosterone/sex hormone binding globulin. RESULTS: Bone loss accelerated at most sites after age 50. There was a significant fall in FAI from the third decade onwards. The levels of all bone markers fell with age. CONCLUSIONS: Bone loss in men appears to accelerate from age 50 and is associated with decreased bone formation which may be associated with falling levels of free androgen.

Adult↗

Differences in bone mineral density, bone mineral content, and bone areal size in fracturing and non-fracturing women, and their interrelationships at the spine and hip.

Osteoporotic fractures are a major public health problem, particularly in women. Bone mineral density (BMD), bone mineral content (BMC), and bone size have been regarded as important determinants of osteoporotic fractures. In 1449 women over age 30 years, we studied the detailed relationship, at the spine and hip, between BMD, BMC, and bone areal size (all measured by dual-energy X-ray absorptiometry) and compared their relative magnitudes in fracturing and non-fracturing individuals. We find that, (1) BMD and BMC are significantly higher at the spine and hip in non-fracturing women. Bone areal size is significantly larger at the spine in non-fracturing women; however, the significance disappears when adjustment is made for the significant difference of height (stature) between fracturing and non-fracturing women. In contrast to the spine, bone areal size is always significantly largerin fracturing women at the hip. (2) The relationship among BMD, BMC, and bone areal size is different at the spine and hip. Specifically, at the spine, BMD increases with bone areal size linearly. At the hip, BMD has a quadratic relationship with bone areal size, so that BMD increases at lower bone areal sizes, then (after an intermediate zone of values) decreases with increasing bone areal size. However, BMD adjusted for BMC always decreases with increasing bone areal size, as expected by the definition of BMD. With no adjustment for BMC, the increase in BMD with bone areal size is due to a more rapid increase of BMC than increasing bone areal size, thus explaining the observations of association of both larger BMD and larger bone areal size with stronger bone. (3) At the spine, 86.2% of BMD variation is attributable to BMC and 12.6% to bone areal size. At the hip, 98.0% of BMD variation is due to BMC and 1.1% due to bone areal size. The current study may be important in understanding the relationship among BMD, BMC, and bone size as risk determinants of osteoporotic fractures.

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Effects of cyclical etidronate with alfacalcidol on lumbar bone mineral density, bone resorption, and back pain in postmenopausal women with osteoporosis.

The purpose of the present open-labeled, randomized, prospective study was to compare the effects of cyclical etidronate combined with alfacalcidol with those of cyclical etidronate alone on lumbar bone mineral density (BMD), bone resorption, and back pain in postmenopausal women with osteoporosis. Forty postmenopausal women with osteoporosis, 60-86 years of age, without any vertebral fractures in the lumbar spine, were randomly divided into two groups with 20 patients in each group. One group was treated with cyclical etidronate (oral etidronate 200 mg daily for 2 weeks every 3 months) and the other was given cyclical etidronate combined with alfacalcidol (cyclical etidronate plus alfacalcidol 1 Ig daily continuously). The BMD of the lumbar spine (L1-L4) measured by dual-energy X-ray absorptiometry, urinary crosslinked N-terminal telopeptides of type I collagen (NTX) measured by an enzyme-linked immunosorbent assay, and back pain evaluated by the face scale score were assessed at baseline, 6 months, and 12 months. There were no significant differences in baseline characteristics including age, body mass index, years since menopause, lumbar BMD, urinary NTX level, and face scale score between the two treatment groups. Both treatments significantly reduced the urinary NTX level and back pain. Cyclical etidronate combined with alfacalcidol significantly increased the lumbar BMD with a more significant reduction in the urinary NTX level than cyclical etidronate alone, but cyclical etidronate alone did not significantly increase the lumbar BMD. Alleviation of back pain was similar in the two groups. These results suggest that cyclical etidronate combined with alfacalcidol appears to be more useful than cyclical etidronate alone for increasing the lumbar BMD by more markedly suppressing bone resorption in postmenopausal women with osteoporosis.

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Effects of alendronate on metacarpal and lumbar bone mineral density, bone resorption, and chronic back pain in postmenopausal women with osteoporosis.

The purpose of this study was to investigate the effect of alendronate on metacarpal and lumbar bone mineral density (BMD), bone resorption, and chronic back pain in postmenopausal women with osteoporosis. Eighty postmenopausal women with osteoporosis, 59-88 years of age, were divided into two groups of 40 each according to the site of BMD measurement: the metacarpus (M) and the lumbar spine (L). All of them were treated with alendronate (5 mg/day) for 12 months. Metacarpal or lumbar BMD was measured by computed X-ray densitometry or dual-energy X-ray absorptiometry in the M or the L group, respectively, at baseline and every 6 months. Urinary cross-linked N-terminal telopeptides of type I collagen (NTX) were measured by enzyme-linked immunosorbent assay, and chronic back pain was evaluated by face scale score at baseline and every 6 months in both groups. There were no significant differences in baseline characteristics, including age, body mass index, years since menopause, urinary NTX level, face scale score, or number of prevalent vertebral fractures per patient between the two groups. Urinary NTX level was reduced and chronic back pain was improved similarly in both groups. Whereas metacarpal BMD did not significantly change in the M group (0.20% increase), lumbar BMD increased by 8.15% in the L group. These results suggest that although alendronate increases BMD of the lumbar spine, which is rich in cancellous bone, and improves chronic back pain, with suppression of bone resorption in postmenopausal women with osteoporosis, it may fail to increase cortical BMD of the metacarpus, a distal site of the upper extremity.

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Alendronate increases bone density and bone strength at the distal radius in postmenopausal women.

In addition to the alendronate Osteoporosis Intervention Trial (FOSIT) core protocol 901-0A of 1908 enrolled patients, the use of peripheral quantitative computed tomography (pQCT) was explored for the assessment of response to therapy. Bone mineral and strength related parameters at two different sites at the distal radius were explored in a subset of the multicenter core study. One hundred and three patients were entered into the substudy and given either a daily dose of 10 mg of alendronate or placebo for 1 year. Measurements were done at months 0, 3, 6, and 12. Inclusion criteria were bone mineral density (BMD) measurements at the lumbar spine of -2 SD. The response to therapy was assessed by dual-energy X-ray absorptiometry in the lumbar spine and the hip, and by pQCT in the ultradistal and the shaft sites of the radius. In line with the FOSIT core study, alendronate increased BMD at the lumbar spine and the hip, and it decreased the serum biochemical markers of bone turnover. The substudy showed differences between the therapy and placebo group in trabecular bone density (8.4%, p = 0.095), in total density (6.8%, p = 0.009), and in the bone strength index (BSI) (15. 6 mm3, p = 0.037) at the ultradistal site due to treatment and no changes at the radius shaft. A significant correlation was observed between percentage changes from baseline in BMD of the lumbar spine, and in total density and bone strength at the ultradistal radius site in the treatment group, but not in the placebo group. Thus, the ultradistal radius site did respond to alendronate therapy. The increased bone density accompanied a significant gain in the BSI at the ultradistal site, a finding that might help explain the reduced wrist fractures in the alendronate Fracture Intervention Trial.

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Bone mineral density, bone turnover, and osteoprotegerin in depressed women with and without borderline personality disorder.

OBJECTIVE: Low bone mineral density has repeatedly been reported in patients with major depressive disorder (MDD), and MDD has been discussed as a risk factor for the development of osteoporosis. MDD in young adults often occurs in the context of borderline personality disorder (BPD), and both MDD and BPD have been associated with a dysregulation of the hypothalamic-pituitary-adrenal system and subsequent hypercortisolemia. To date, it is unclear whether comorbid BPD in depressed patients modulates the extent of bone mass reduction. Therefore, we examined bone density, markers of bone turnover, and proinflammatory cytokines in depressed patients with and without BPD. Patients with BPD alone and healthy women served as comparison groups. METHOD: Twenty-four patients with MDD and 23 patients with comorbid MDD and BPD were included. Sixteen patients with BPD and 20 healthy women of similar body mass index served as the comparison group. BMD was assessed by means of dual-energy x-ray absorptiometry. Markers of bone turnover, endocrine and immune parameters were determined. For data analysis, the group of depressed patients without comorbid BPD was divided according to age into two groups (younger depressed patients with a mean age of 30 years and older patients with a mean age of 42.9 years). RESULTS: BMD at the lumbar spine was significantly reduced in a) depressed women with comorbid BPD (mean age, 28.6 years) and in b) older depressed patients without BPD (mean age, 42.9 years). Osteocalcin, a marker of osteoblastic activity, and crosslaps, a marker of bone loss, were significantly different between the study groups. Tumor necrosis factor-alpha was increased in depressed patients when compared with healthy women. Furthermore, TNF-alpha was positively correlated with serum crosslaps, a marker for osteoclastic activity. CONCLUSION: Depression is associated with reduced bone mass, in particular in patients with comorbid BPD. Possible factors contributing to BMD reduction include endocrine and immune alterations associated with either MDD or BPD. We conclude from our data that a history of MDD with and without comorbid BPD should be considered as a risk factor in clinical assessment instruments for the identification of persons prone to osteoporosis.

Adult↗

Cross sectional investigation of the effects of inhaled corticosteroids on bone density and bone metabolism in patients with asthma.

BACKGROUND: Bone mineral density has been reduced in patients with asthma taking inhaled corticosteroids in some cross sectional studies and this could be important if treatment is continued for several decades. The possibility of confounding by age, menopausal status, physical activity and, especially, past oral steroid use has not been excluded in most studies. The present study was designed to assess the magnitude of any reduction in bone mineral density in relation to inhaled steroid use after adjusting for these factors. METHODS: Bone mineral density (BMD), vertebral fractures, and markers of bone metabolism (serum osteocalcin, procollagen peptide I, bone-specific alkaline phosphatase, and urinary deoxypyridinoline cross links) were measured in 81 patients with asthma age 20-40 years; 34 patients (19 men) who had never had inhaled or systemic steroids and 47 (19 men) who had taken inhaled steroids for at least five years with limited exposure to systemic steroids in the past. Data relating to past medication use, physical activity, smoking, and other confounding factors were collected by questionnaire. The relation between inhaled steroid dose and duration and BMD was assessed by linear regression analysis, accounting for potential confounders including weight, exercise, and oral steroid use. RESULTS: The 47 patients taking an inhaled steroid had a mean current dose of 620 micrograms/day (range 100-3000 micrograms), a mean duration of use of 7.8 years, and had had a mean of 0.85 courses of prednisolone in the past. There was no significant difference in mean BMD values between those who were and those who were not on inhaled steroids in men or women. However, on multivariate analysis, cumulative inhaled steroid dose was associated with a reduction in posterior-anterior (P-A) and lateral lumbar spine bone mineral density in women, equivalent to a 0.11 standard deviation reduction in bone density per 1000 micrograms/day inhaled steroid per year after adjustment for potential confounding factors (95% CI for P-A spine 0.01 to 0.22; for lateral spine 0.02 to 0.21). Previous oral steroid use was not an important confounding factor in these patients. Inhaled steroid use was not related to BMD at the wrist or hip in women or at any skeletal site in men. Women taking an inhaled steroid had lower levels of serum osteocalcin than those not taking them, although this was not dose related. Inhaled steroid use was not associated with differences in other markers of bone metabolism in men or women or with the presence of vertebral fractures. CONCLUSIONS: Although an effect of confounding factors cannot be excluded entirely in a cross sectional study, our findings are in keeping with an effect of inhaled steroid therapy in reducing bone density in the spine in women and provide an estimate of the magnitude of this effect.

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Effects of raloxifene hydrochloride on bone mineral density, bone metabolism and serum lipids in Chinese postmenopausal women with osteoporosis: a multi-center, randomized, placebo-controlled clinical trial.

BACKGROUND: Raloxifene has been approved for prevention and treatment of postmenopausal osteoporosis in Caucasian women. It also has some positive effects on serum lipids in Caucasians. The objective of this study was to determine the effect of raloxifene hydrochloride on lumbar spine and total hip bone mineral density (BMD), bone metabolism, and serum lipids in Chinese postmenopausal women with osteoporosis. METHODS: This was a multi-center, randomized, double-blind, placebo-controlled clinical trial in which 204 postmenopausal Chinese women with osteoporosis were assigned to receive raloxifene (60 mg) or placebo treatment daily for 12 months. BMD, serum bone metabolism markers, and serum lipids were measured before and after drug administration. BMD was measured by Dual-Energy X-Ray Absorptiometry (DEXA) and bone metabolism markers were analyzed by one-step enzyme-linked immunosorbent assay. Serum lipids were measured by enzymatic analysis. RESULTS: At the end of the 12-month study, lumbar spine BMD increased in both groups with a mean increase of (3.3 +/- 4.8)% in the raloxifene group and (1.0 +/- 4.9)% in the placebo group (P < 0.001). There was a mean increase in total hip BMD of (1.4 +/- 4.8)% in the raloxifene group and a mean decrease of (0.9 +/- 5.0)% in the placebo group (P < 0.001). No subject in the raloxifene group had a new vertebral fracture and 5 placebo subjects had new fractures (P > 0.05). In the raloxifene group, the median decreases in the biochemical markers of bone metabolism serum osteocalcin and C-telopeptide were 41.7% and 61.5%, respectively. These changes were statistically significant compared with those in the placebo group (10.6% and 35.6%, P < 0.001, respectively). Both total cholesterol and low-density lipoprotein cholesterol decreased significantly in the raloxifene group compared with those in the placebo group (P < 0.001, respectively) and there was no significant effect of raloxifene on high-density lipoprotein cholesterol and triglycerides compared with placebo. CONCLUSIONS: Raloxifene 60 mg/d for 12 months significantly increases lumbar spine and total hip BMD, significantly decreases bone turnover, and has favourable effects on serum lipids in Chinese postmenopausal women with osteoporosis.

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Associations of vitamin D status with bone mineral density, bone turnover, bone loss and fracture risk in healthy postmenopausal women. The OFELY study.

INTRODUCTION: Vitamin D status is considered as an important determinant of bone health but supplementation trials with vitamin D(3) have yielded conflicting results. The aim of this study was to investigate the associations between serum 25-hydroxyvitamin D (25-OH D), bone turnover markers, bone mineral density (BMD), radius bone loss and incidence of fracture in postmenopausal women. METHODS: 669 postmenopausal women (mean age: 62.2 years) belonging to a population-based cohort were followed prospectively for a median of 11.2 years. At baseline, 25-OH D levels, BMD, bone turnover markers and clinical risk factors of osteoporosis were assessed. BMD loss at the radius was estimated by annual measurements of BMD and all incident fractures which occurred in 134 women were confirmed by radiographs. RESULTS: 73% and 35% of women had serum 25-OH D levels below 75 and 50 nmol/l which correspond respectively to the median and lowest optimal values recently proposed for fracture prevention. 11% of women had levels below 30 nmol/l. Serum 25-OH D correlated modestly with intact PTH (r(2)=0.023, p<0.0001), but not with bone turnover markers or BMD at the hip and radius after adjustment for age. When levels of 25-OH D were considered as a continuous variable, there was no significant association between 25-OH D levels and radius BMD loss or fracture risk. After adjustment for age, there was no significant difference in incidence of fracture, BMD, radius BMD loss, bone turnover markers, grip strength and the percentage of fallers in the previous year between women with 25-OH D levels below or above 75, 50 or 30 nmol/l. CONCLUSIONS: In a population of home-dwelling healthy postmenopausal women with few of them with severe vitamin D deficiency, vitamin D status may not be an important determinant of bone health.

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The effect of pregnancy on bone density and bone turnover.

During pregnancy, the mother adapts to meet the calcium demands of the fetus. The effect of this adaptation on the maternal skeleton is not fully understood. Our objectives were to evaluate changes in bone mineral density (BMD) and bone turnover during pregnancy. We studied 16 women longitudinally, with baseline measurements before pregnancy; then at 16, 26, and 36 weeks of pregnancy; and postpartum. We measured total-body BMD and biochemical markers of bone resorption (urinary pyridinium crosslinks and telopeptides of type I collagen) and bone formation (serum bone alkaline phosphatase, propeptides of type I procollagen [PINP] and osteocalcin). We also measured parathyroid hormone (PTH), insulin-like growth factor I (IGF-I), and human placental lactogen. Postpartum, BMD increased in the arms (2.8%, P < 0.01) and legs (1.9%, P < 0.01) but decreased in the pelvis (-3.2%, P < 0.05) and spine (-4.6%, P < 0.01) compared with prepregnancy values. All biochemical markers, with the exception of osteocalcin concentration, increased during pregnancy. The change in IGF-I at 36 weeks was related to the change in biochemical markers (e.g., PINP, r = 0.72, P = 0.002). Pregnancy is a high-bone-turnover state. IGF-I levels may be an important determinant of bone turnover during pregnancy. Elevated bone turnover may explain trabecular bone loss during pregnancy.

Adult↗

The oxidative metabolism of estradiol conditions postmenopausal bone density and bone loss.

Because lifelong exposure to estrogen is a strong determinant of bone mass, we asked whether metabolic conversion of estrogen to either inactive or active metabolites would reflect postmenopausal bone mineral density (BMD) and rate of bone loss. Biochemical markers of inactive estrogen metabolites, urinary 2-hydroxyestrogen (2OHE1) and 2-methoxyestrogen (2MeOE1), and active metabolites, urinary 16alpha-hydroxyestrone (16alphaOHE1), estradiol (E2), and estriol (E3), were determined in 71 untreated, healthy postmenopausal women (age, 47-59 years) followed prospectively for 1 year. Urinary 2MeOE1 was correlated negatively with baseline vertebral (anteroposterior [AP] projection, r = -0.23 andp < 0.05; lateral view, r = -0.27 and p < 0.05) and proximal femur bone density measured by dual-energy X-ray absorptiometry (DXA; total, r = -0.38 and p < 0.01; neck, r = -0.28 and p = 0.02; trochanter, r = -0.44 and p < 0.01). BMDs of women in the lowest quartile of urinary 2MeOE1 (< 15 ng/g) were significantly higher than those in the highest quartile at all skeletal sites (p < 0.05). Likewise, women in the lowest quartile of urinary 2OHE1/16alphaOHE1 ratio (< 1.6) did not experience bone loss after 1 year, in contrast to women in the higher quartiles. We propose that the rate of inactivation of estrogens through 2-hydroxylation may contribute to postmenopausal osteoporosis.

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Effect of Gengnianchun Recipe on bone mineral density, bone biomechanical parameters and serum lipid level in ovariectomized rats.

OBJECTIVE: To observe the effect of Gengnianchun Recipe (GNC) on bone mineral density (BMD), bone biomechanical parameters and serum lipid level in the bilaterally ovariectomized (OVX) rats and to explore the prophylactic and therapeutic action of GNC on ovariectomy induced osteoporosis and hyperlipidemia. METHODS: OVX SD rats, 10 - 12 months old, were divided into different groups and fed with GNC 2 g/d, GNC 1 g/d and Nilestriol 0.125 mg/week, respectively for 4 months to observe the change of BMD and bone biomechanical parameters of the lumbar vertebrae, and the serum levels of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), and to compare the effect of the two drugs on the morphology of the uterus. RESULTS: There was marked reduction in BMD and biomechanical parameters in lumbar vertebrae (P < 0.01) and increase of serum TC and LDL-C levels (P < 0.01) in rats after OVX. GNC or Nilestriol significantly improved the decreased BMD and biomechanical parameters of the lumbar vertebrae (P < 0.05 or P < 0.01), and reduced the serum TC and LDL-C levels (P < 0.01). In the Nilestriol group, the wet weight of uterus got increased obviously (P < 0.01), the number of uterine glands increased, uterine columnar epithelium thickened, and the mitotic figures in the epithelial stroma and myointimal cells augmented. But no such effect in wet weight and morphology of uterus was found in the GNC group. CONCLUSION: GNC could increase the BMD and biomechanical parameters of the lumbar vertebrae, reduce the serum TC and LDL-C levels, yet produce no adverse reaction in stimulating proliferation and hypertrophy of uterus.

Animals↗

Effects of raloxifene hydrochloride on bone mineral density, bone metabolism and serum lipids in postmenopausal women: a randomized clinical trial in Beijing.

OBJECTIVE: To determine the effects of raloxifene hydrochloride (RLX) on bone mineral density (BMD), bone metabolism markers and serum lipids in healthy postmenopausal women in Beijing. METHODS: A multicenter, randomized, double-blind, placebo-controlled study was conducted in a total of 204 healthy postmenopausal women (age 59.5 +/- 5.0 years and weight 62.8 +/- 8.7 kg) treated with either RLX 60 mg (n = 102) or placebo (n = 102) daily for 12 months. BMD, serum lipids, and bone markers were measured before and after drug administration. RESULTS: Compared with placebo, RLX produced a significant increase in both total lumbar spine and total hip BMD. For the lumbar spine, percentage increase in total BMD was 2.3% with RLX compared with a decrease of 0.1% with placebo (P < 0.001). Corresponding values for total hip BMD were a 2.5% increase for RLX and a 1.1% increase for placebo (P = 0.011). For biochemical markers of bone metabolism, serum osteocalcin and C-telopeptide, percentage decreases were 27.65% and 24.02% in RLX-treated subjects. Corresponding values in placebo were a 10.64% decrease and a 15.75% increase (RLX compared with placebo, both P < 0.001). For total cholesterol and low-density lipoprotein cholesterol levels, percentage decreases were 6.44% and 34.58% in the RLX-treated group. Corresponding values in placebo-treated patients were a 1.44% increase and a 19.07% decrease (RLX compared with placebo, both P < 0.001). No differences were found for high-density lipoprotein cholesterol or triglyceride levels between the two groups. Only 5 subjects discontinued early owing to an adverse event (3 in the RLX group and 2 in the placebo group). CONCLUSIONS: This study confirms that RLX exerts positive effects on the skeleton, increasing BMD and decreasing biochemical markers of bone metabolism, and has a positive effect on the overall serum lipid profile in postmenopausal women in China.

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Bone quality factor analysis: a new noninvasive technique for the measurement of bone density and bone strength.

The sensitivity of bone mineral density (BMD) as a predictor of fracture risk is limited by the fact that this index does not take into account the geometrical and material characteristics of bone. In contrast, both BMD and bone architecture influence the quality factor (QF), the fraction of the inverse of the energy lost in one cycle of deformation. In this study we have compared the sensitivity of a QF analyzer and dual-energy X-ray absorptiometry (DXA) in detecting the changes induced by ovariectomy (OVX) on the QF, impact strength, and BMD of the femur of mature rats. QF and BMD were measured noninvasively before and 4 weeks after OVX or sham operation using a QF analyzer developed in our laboratory and a Hologic QDR 2000 bone densitometry, respectively. Impact strength was measured in excised femurs at the end of the study. The in vivo short-term precision (coefficient of variation) of the QF analyzer was 1.9%. BMD and QF measurements were highly correlated (r = 0.80,p <0.0001). At baseline, QF and BMD were similar in OVX and sham-operated rats. At 4 weeks, BMD was 14.7 + or - 0.9% lower than at baseline (p < 0.001) in OVX rats and 5.3 + or - 1.3% lower in sham-operated rats (p <0.05). QF decreased 36.0 + or - 2.8% (p <0.0001) in OVX and 10.6 + or - 3.6% in sham rats (p <0.01). As a result, at 4 weeks the difference between sham-operated and OVX rats was larger (p < 0.05) by QF than by BMD. Moreover, QF correlated better than BMD with impact strength and the difference in impact strength between sham and OVX mice was closer to that in QF than that in BMD. These data demonstrate that QF analysis is a precise technique that is more sensitive than DXA in detecting the changes in bone density and strength induced by OVX. QF analysis may represent a new, simple, and economic technique for predicting fracture risk.

Animals↗

Melorheostosis. A case report with special reference to bone mineral density, bone circulation and bone scan.

A new case of melorheostosis is presented. Bone mineral density, and bone circulation were determined and bone scan carried out in the patient. The bone mineral density measured by photon absorption in the region of the distal radius of the patient's left forearm was found to be within normal limits, the bone blood circulation determined by Xc-133 clearance method was better in the affected side, and an area of increased uptake of Tc99m was found by bone scanning in the affected extremity.

Adult↗

Pregnancy-associated changes in bone density and bone turnover in the physiological state: prospective data on sixteen women.

Areal bone mineral density (BMD, g/cm 2) was measured for the total body, lumbar spine and hip with dual-energy x-ray absorptiometry (DXA) before pregnancy and after delivery in sixteen women aged 21 - 35 years. Additional measurements included quantitative ultrasound indices (broadband ultrasound attenuation, BUA, at the calcaneus at baseline and at 16, 26, and 36 weeks of pregnancy, and postpartum) as well as biochemical markers of bone formation and resorption (measured before pregnancy and during pregnancy at 16, 22, 26, 30, 34, and 36 weeks of pregnancy and postpartum). The results of measurements were as follows: 1. Postpartum BMD showed a significant reduction in the total body (- 13.4 %), in the spine (- 9.2 %) and in the hip (-7.8 % at the femoral neck and - 9.2 % at the Ward's triangle) compared to pre-pregnancy values. 2. Biochemical markers of bone resorption increased by 26 weeks. 3. Bone ultrasound measurements that provide information on bone density before delivery did not change throughout pregnancy. A significant reduction of BUA (- 14.5 % compared to baseline) was observed postpartum only. These data would suggest that pregnancy-induced bone loss develops rapidly after the 36 week of pregnancy, possibly via enhanced bone resorption.

Absorptiometry, Photon↗

Bone mineral density, bone metabolism and body composition of children with chronic renal failure, with and without growth hormone treatment.

OBJECTIVE: Osteopenia has been reported in adult patients with chronic renal failure (CRF). Only a few studies have been performed in children. The objective of this study was to evaluate bone mineral density (BMD), bone turnover, body composition in children with CRF and to study the effect of GH on these variables. DESIGN: Two groups were identified: patients with growth retardation who received GH (GH-group) and patients most of whom were not growth retarded who did not receive GH (no-GH-group). After an observation period of 6 months, the patients in the GH-group started GH treatment. Patients were studied every 6 months during 18 months. PATIENTS: Thirty-six prepubertal patients (27 boys and 9 girls), mean age 7.9 years, with CRF participated in the study. The GH-group consisted of 17 patients of whom 14 completed one year treatment. The no-GH-group consisted of 19 patients, of whom 16 were followed for 6 months, 14 for 12 months and 13 for 18 months. MEASUREMENTS: Lumbar spine BMD, total body BMD and body composition were assessed by dual energy X-ray absorptiometry, compared to age-and sex-matched reference values of the same population and expressed as standard deviation scores (SDS). BMD of appendicular bone was measured by quantitative microdensitometry (QMD). Blood samples were obtained to assess bone metabolism and growth factors. RESULTS: Baseline mean lumbar spine and total body BMD SDS of all patients were not significantly different from normal. Mean lumbar spine and total body BMD SDS did not change significantly in the GH-group during GH treatment. The change of QMD at the midshaft during the first 6 months of GH treatment was significantly smaller than during the observation period (P < 0.01). Height SDS and biochemical markers of both bone formation and bone resorption increased significantly during GH treatment; 1,25-dihydroxyvitamin D remained stable. Lean tissue mass increased (P < 0.001) and percentage body fat decreased (P < 0.01) during GH treatment. BMD, the biochemical markers of bone turnover which are independent of renal function, and body composition remained stable in the no-GH-group. CONCLUSIONS: Mean lumbar spine and total body BMD of children with chronic renal failure did not differ from healthy controls. The lack of a GH-induced increase in 1,25-dihydroxyvitamin D levels, probably due to treatment with alpha-calcidol, might be linked to the absence of a response in BMD during GH treatment in children with chronic renal failure.

Body Composition↗