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1.
Background: Bioelectrical impedance analysis (BIA) is a widely available tool which provides mineral estimate. However, BIA is not currently recognized as a bone mineral measuring method. This study aimed to explore the ability of BIA to predict bone mineral content (BMC) in children, using dual-energy X-ray absorptiometry as a gold standard. Methods: Healthy children aged 6–12 years (n = 176) were recruited for BIA and dual-energy X-ray absorptiometry measurements. Predictive models were generated using basic indices (age, height, weight, waist circumference, hip circumference, etc.) and BIA parameters (minerals, fat mass, and fat free mass). Results: The root-mean-square deviation and R2 for the total BMC predictive model were 0.089 kg and 0.926, respectively using height and weight as predictors whereas 0.113 kg and 0.886, respectively using minerals by BIA. The root-mean-square deviation and R2 for the subtotal BMC predictive model were 0.080 kg and 0.935, respectively using height and weight as predictors whereas 0.098 kg and 0.906, respectively using minerals by BIA. The best predictive models included basic indices and BIA parameters as predictors, but they had only slightly better performance over simple models. Conclusions: Mineral content by BIA was good predictor of total and subtotal BMC in healthy children but with similar overall model performance compared to basic indices. More complex models combined all the predictive variables gave better prediction power, but of little improvement to these simple models. The BIA instrument does not appear to be useful in estimating BMC in healthy children as basic indices are more widely available measures but provide comparable performance. Future studies are needed to determine the clinical usefulness of the more complex prediction model in children with disease or children in other subgroups.  相似文献   

2.
Bone and mineral metabolism has been reported to affect the development of the ossification of the posterior longitudinal ligament (OPLL). The aim of this study was to compare bone mineral densities (BMD) and rate of osteoporosis between cervical OPLL and a matched control group. We also investigated the correlation of BMD with the number of cervical spine levels involved with OPLL. From 1999 to August 2011, 178 patients with cervical OPLL underwent dual-energy X-ray absorptiometry (DXA) at our institute. The control group was age-, sex-, and body mass index (BMI)–matched with the OPLL group on a 1:1 basis. BMD was measured at the lumbar spine (L1–L4), femoral neck, and total femur using DXA. Age, sex, and BMI were the same in the OPLL and control groups. BMDs of the OPLL and control groups were significantly different in the lumbar spine, femoral neck, and total femur (p = 0.0001, 0.0001, 0.009, respectively). Rates of osteopenia and osteoporosis were lower in the OPLL than in the control group according to lumbar spine and femoral neck DXA (p = 0.01, 0.03, respectively). A positive correlation was observed between lumbar spine BMD and the number of cervical spine levels involved with OPLL (p = 0.004).  相似文献   

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The purpose of the present parent–offspring study was to investigate the influence of heredity and environment on bone density in young men. Another aim was to discover whether the same genetic factors influence bone mass, lean mass and muscle strength. Fifty families including a father, mother and one son were investigated. The mothers (aged 44.5 ± 4.4 years) and fathers (aged 47.1 ± 4.4 years) generally had a sedentary lifestyle with little physical activity. As a contrast, all but three of the sons (aged 17.0 ± 0.4 years) were active in ice hockey training. Bone mineral density (BMD, g/cm2) of the total body, head, lumbar spine and femoral neck was measured using dual-energy X-ray absorptiometry. Muscle strength of the hamstrings and quadriceps muscles was also measured in the boys. BMD values of different sites in the fathers, mothers and sons were adjusted for weight, height, age, and any significant influence of environment. Heritability estimates were obtained as regression coefficients with the boys’ adjusted BMD as dependent variable and the adjusted midparent bone density (father BMD + mother BMD/2) as independent variable. Accordingly, heritability explained 34–54% of the variation in the sons’ BMD. Midparent BMD of several sites also predicted the boys’ lean mass and quadriceps strength, and midparent–offspring differences in lean mass predicted midparent–offspring differences in BMD of the total body, head and spine (β= 0.30–0.51, p<0.05). The sons were found to have almost 30% higher femoral neck BMD than their fathers, and physical activity (hours/week) predicted BMD at several sites among the sons β= 0.26–0.34, p <0.05). In conclusion, heritability is a main determinant of the variance in BMD in young men. Based on the results we suggest that the same genetic factors may influence bone mass, lean mass and muscle strength by affecting body size. The present study also emphasizes the importance of physical activity for the development and maintenance of BMD in men. Received: 26 October 1998 / Accepted: 24 February 1999  相似文献   

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Bone loss during advancing age in women and men is partly the result of sex steroid deficiency. As the contribution of circulating sex steroids and sex hormone-binding globulin (SHBG) to bone loss remains uncertain, we sought to determine whether levels of sex steroids or SHBG predict change in bone mineral density (BMD) in women and men. A population-based study in the city of Tromsø of 6.5 years’ duration (range 5.4-7.4) included 927 postmenopausal women aged 37–80 years and 894 men aged 25–80 years. Total estradiol and testosterone, calculated free levels, and SHBG were measured at baseline, and BMD change at the distal forearm was determined using BMD measurements in 1994–1995 and 2001. Bone loss was detected in postmenopausal women and men. Free estradiol and SHBG predicted age-adjusted bone loss in postmenopausal women, but only free estradiol was associated after further adjustment for body mass index and smoking in mixed models (P < 0.05). After same adjustment, only SHBG persisted as a significant independent predictor of bone loss in men (P < 0.001). However, only 1% of the variance in bone loss was accounted for by these measurements. We therefore conclude that the relations between sex steroids and bone loss are weak and measurements of sex steroids are unlikely to assist in clinical decision making.  相似文献   

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The trabecular bone score (TBS) is a new parameter that is determined from gray-level analysis of dual-energy X-ray absorptiometry (DXA) images. It relies on the mean thickness and volume fraction of trabecular bone microarchitecture. This was a preliminary case-control study to evaluate the potential diagnostic value of TBS as a complement to bone mineral density (BMD), by comparing postmenopausal women with and without fractures. The sample consisted of 45 women with osteoporotic fractures (5 hip fractures, 20 vertebral fractures, and 20 other types of fracture) and 155 women without a fracture. Stratification was performed, taking into account each type of fracture (except hip), and women with and without fractures were matched for age and spine BMD. BMD and TBS were measured at the total spine. TBS measured at the total spine revealed a significant difference between the fracture and age– and spine BMD–matched nonfracture group, when considering all types of fractures and vertebral fractures. In these cases, the diagnostic value of the combination of BMD and TBS likely will be higher compared with that of BMD alone. TBS, as evaluated from standard DXA scans directly, potentially complements BMD in the detection of osteoporotic fractures. Prospective studies are necessary to fully evaluate the potential role of TBS as a complementary risk factor for fracture.  相似文献   

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In a longitudinal study of 395 normal 10- to 24-year-old female volunteers, 105 of whom were initially premenarcheal, lumbar bone mineral density (BMD) and content (BMC) were measured by dual-energy X-ray absorptiometry (DXA) at inclusion and after a 2-year interval. The mean age of menarche was 13.1 t 1.1 years (n = 395). In a multiple regression analysis the BMD and BMC relative gains were highly correlated with the height and weight relative gains and with the time since menarche (r= 0.91 and r= 0.93, respectively). The mean relative annual increments in body height, in L2–4 vertebral height, in BMD and in BMC peaked respectively at 1.5, 1.0, 0.6 and 0.7 years before menarche. The four perimenarcheal years, beginning with the first pubertal clinical signs, are essential for bone acquisition, since 46.7% of adult BMC is acquired during this period. Two years after menarche, BMC is 85% of the adult value. Seven years after menarche no further significant variation in BMC is observed. In 206 menstruating women 27–47 years old, a DXA lumbar measurement was also performed after a 4-year interval. There was a small but significant increase of 0.3 %/year in BMD and 0.7 %/year in BMC, contrasting with the results in the young population. This could be explained by a volumetric expansion with aging, which is supported by a small increase in L2–4 area (0.4 %/year). In conclusion, this longitudinal study on the lumbar site emphasizes the importance of the pre- and perimenarcheal period, when half of lumbar adult BMC is acquired. This suggests that greater attention must be paid to this period regarding nutrition and physical activity. Received: 15 May 1998 / Accepted: 19 October 1998  相似文献   

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Introduction

Bronchopulmonary dysplasia (BPD) is the most common complication of extreme preterm delivery, and is associated with reduced exercise tolerance and exercise capacity. The aim of this study was to assess the effects of a physical activity programme on exercise tolerance, exercise capacity, flexibility, and lung function in prematurely born children with BPD.

Methods

This was a randomized controlled trial. Preterm children with BPD (4–6 years) were randomized to intervention (IG) and control (CG) groups. The CG did not participate in any physical activity during the study period. The IG performed a 4-week exercise programme based on aerobic interval and resistance training. Outcomes were based on the 6-minute walk test (6MWT), incremental shuttle walk test (ISWT), modified sit and reach test (MSRT) and spirometry results.

Results

Twenty individuals were recruited. In the IG (n = 10), statistical and clinical improvement was observed in the 6MWT (316.3 ± 31.4 m vs 376.2 ± 39.5 m; P = .002). Significant improvements were also seen in the IG in the ISWT (248.0 ± 45.2 m vs 465.3 ± 58.2 m; P = .013), MSRT (14.5 ± 7.7 cm vs 22.8 ± 6.9 cm; P = .003), and FEV1 (102% ± 16% pred vs 104% ± 17% pred; P = .004). No significant differences between pre- and post-intervention were observed in the CG for all outcomes (n = 10).

Conclusion

This 4-week programme resulted in statistical and clinical improvements in exercise tolerance, exercise capacity and flexibility in preterm children with BPD.  相似文献   

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Osteoporosis is a major complication of Cushing’s syndrome. The aim of the present study was to assess the chronologic effect of surgical cure on bone mineral density (BMD) in patients with Cushing’s syndrome due to adrenal adenoma. BMD was examined in 28 patients before laparoscopic adrenalectomy; 17 patients with reduced BMD were then included in the longitudinal evaluation. BMD was determined using dual energy X-ray absorptiometry (DXA) before and at 3, 6, 12, 18, and 24 months after adrenalectomy. The prevalence of osteoporosis was 64% (95% confidence interval 44–81%). Preoperative BMD of the lumbar spine in the lateral projection was significantly lower than that of the femoral neck (mean ± SD score: −3.53 ± 0.75 vs. −1.54 ± 0.22, p = 0.003). A significant increase in BMD was observed at 3 months after surgery in the lumbar spine (p = 0.0004). Improvement at both sites was maintained at 24 months after surgery. The postoperative percentage change in BMD of the lumbar spine was significantly higher than that of the femoral neck (mean ± SD 36.7% ± 26.5% vs. 11.2% ± 12.1%, p = 0.01). The change in the seven premenopausal patients was significantly higher than that in the three postmenopausal patients (p = 0.0006). Surgical cure of hypercortisolism provides significant improvement in BMD in patients with Cushing’s syndrome due to adrenal adenoma. The improvement is particularly apparent in the lumbar spine measured in the lateral projection. Premenopausal women are more likely to benefit from surgery in terms of secondary osteoporosis.  相似文献   

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Aging Inuit women are at increased risk for low vitamin D status due to habitation at higher latitudes, darker skin, and ongoing nutrition transition. Lower serum 25-hydroxyvitamin D (25[OH]D) concentration and higher risk of fracture have been separately reported in Inuit women, with particular relevance to postmenopausal women. We evaluated vitamin D status, forearm bone mineral density (fBMD), and nutrition in Inuit women ≥40 years. Women (n = 568) were randomly selected to participate in the 2007–2008 International Polar Year Inuit Health Survey from 36 Arctic communities. fBMD was measured using peripheral dual-energy X-ray absorptiometry. Dietary intakes were derived from 24 h recall and food-frequency questionnaires. Fasting serum 25(OH)D, parathyroid hormone, and osteocalcin (OC) were measured using a LIAISON? automated analyzer. The weighted prevalence of women having 25(OH)D concentration below 37.5, 50, and 75 nmol/L was 7.2 %, 17.6 %, and 48.6 %, respectively, with older women having better status. The dietary density of most nutrients increased with age, as did traditional food intake. fBMD was low in 3 (1.4 %) premenopausal (Z score < −2) and 107 (29.6 %) postmenopausal (T score < −1.5) women. Regression revealed that either weight, body mass index, or percent body fat significantly predicted fBMD in premenopausal women, in addition to age and OC in postmenopausal women. Women ≥50 years have higher vitamin D status and more nutrient-dense diets than women 40–49 years. While measures of adiposity predicted fBMD in all women, additional predictors after menopause included age and bone turnover.  相似文献   

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The vertebral bone mineral density (BMD), bone mineral content (BMC) and bone area of the lumbar spine were measured using a bone densitometer in 8789 women aged 33–73 years who had had no previous hormone replacement therapy (HRT). The overall relationship between BMD and age was analyzed on a year-by-year basis, and comprised three separate regions that could each be described by a straight line: 33–46 years (gradient = 0.00166 g cm−2/year), 47–63 years (gradient = 0.0121 g cm−2/year) and 64–73 years (gradient = 0.0045 g cm−2/year). Above the age of 50 years our results were higher than the BMD in most previous reports. In those 3198 women who knew the time of their last menstrual period (mean age 49.25 years, SD 4.83) bone loss was most rapid in the first 10 menopausal years. In the whole group, the relationship between BMC and age was found to be similar to that of BMD, with three distinct regions, including a rapid drop between the ages of 47 and 63 years (gradient 0.781 g/year). Bone area showed a much more gradual (though significant) decrease with age. Based on WHO definitions and using BMD as an indicator, the percentage of women with osteoporosis varied from zero in the younger age group to about 30% of women aged over 70 years; in contrast, where BMC was used, although the trend with age had a similar shape, the percentages at each year were about half those derived from the corresponding BMD values. Osteopenia derived in the same way occurred in about 50% of women over 70 years using either BMD or BMC. The results presented here provide a reliable local reference range for lumbar spine bone densitometry measurements. They also show that for this site BMD and BMC cannot be used interchangeably to define osteoporosis. Received: 13 March 1998 / Accepted: 23 September 1998  相似文献   

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Intravenous zoledronate reduces fracture risk (5 mg at 18-month intervals) and prevents bone loss (doses of 1 to 5 mg for 3 to >5 years), but the duration of action of a single 5 mg dose and the effects of lower doses beyond 5 years are unknown. We report the second open-label extension (years 5 to 10) of a 2-year randomized, multidose, placebo-controlled, double-blinded trial. A total of 116 older women who completed 5 years of participation either continued observation without further treatment (zoledronate 5 mg and placebo at baseline) or received repeat doses of 1 or 2.5 mg zoledronate (zoledronate 1 mg and zoledronate 2.5 mg at baseline, respectively). Outcomes were spine, hip, and total body bone mineral density (BMD) and serum markers of bone turnover. After a single 5 mg dose of zoledronate, mean BMD at the lumbar spine and total hip was maintained at or above baseline levels for 9 and 10 years, respectively. The mean level of the bone resorption marker β-C-terminal telopeptide of type I collagen (β-CTX) was at least 25% lower than that in the placebo group for 9 years. In women administered 5-yearly doses of 2.5 mg zoledronate, mean BMD at the total hip and lumbar spine was maintained at or above baseline levels for 9 and 10 years, respectively. Redosing with 1 or 2.5 mg zoledronate at 5 years reduced bone turnover markers for 3 to 4 years. BMD increased for 3 to 4 years after redosing with 1 mg zoledronate. In the group given 5-yearly 2.5 mg zoledronate, β-CTX was at least 20% lower than that in the placebo group for 10 years. Both a single baseline 5 mg dose of zoledronate and 5-yearly doses of 1 and 2.5 mg zoledronate prevented bone loss at hip and spine for 8 to 10 years in older postmenopausal women. Clinical trials to evaluate the effects on fracture risk of these very infrequent and lower doses of zoledronate are justified. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   

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The aim of this study was to evaluate a general school-based 1-year exercise intervention program in a population-based cohort of girls at Tanner stage I. Fifty-three girls aged 7–9 years were included. The school curriculum-based exercise intervention program included 40 minutes/school day. Fifty healthy age-matched girls assigned to the general school curriculum of 60 minutes physical activity/week served as controls. Bone mineral content (BMC, g) and areal bone mineral density (aBMD, g/cm2) were measured with dual X-ray absorptiometry (DXA) of the total body (TB), lumbar spine (L2–L4 vertebrae), third lumbar vertebra (L3), femoral neck (FN), and leg. Volumetric bone mineral density (g/cm3) and bone width were calculated at L3 and FN. Total lean body mass and total fat mass were estimated from the TB scan. No differences at baseline were found in age, anthropometrics, or bone parameters when the groups were compared. The annual gain in BMC was 4.7 percentage points higher in the lumbar spine and 9.5 percentage points higher in L3 in cases than in controls (both P < 0.001). The annual gain in aBMD was 2.8 percentage points higher in the lumbar spine and 3.1 percentage points higher in L3 in cases than in controls (both P < 0.001). The annual gain in bone width was 2.9 percentage points higher in L3 in cases than in controls (P < 0.001). A general school-based exercise program in girls aged 7–9 years enhances the accrual of BMC and aBMD and increases bone width.  相似文献   

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BackgroundFollowing the positive experience of the national project “A transplant...and now it’s time for sport,” the Transplant Reference Center of the Emilia-Romagna Region has pursued the promotion of pre- and post-transplant physical exercise by developing a network.MethodsThe path involved the transplant centers and operative units (UU.OO) who wanted to target transplant and waiting list patients, who are clinically stable, to perform personalized exercise through a program (supervised or not) prescribed by a specialist in sports medicine. With the collaboration of the Collective Prevention and Public Health Service, the network was established, consisting of the sports medicine centers and the gyms that promote health for adapted physical activity (PS-AMA). To implement the network, training courses for all the professionals involved (doctors, nurses, exercise specialists) and operational meetings in the transplant centers-nephrology units with patients’ associations have been organized.ResultsTo date, there are 14 transplant centers and UU.OO, 9 sports medicine centers, and 45 PS-AMA involved in this network. Seven training courses were organized with the participation of 193 health professionals. Since January 2016, there have been 65 transplanted patients and 5 patients on the waiting list who practice the prescribed exercise. Of these, 45 carry out supervised exercise in PS-AMA; 25 perform autonomous exercise. Each patient is monitored every 6 months. No problems related to the exercise performance were recorded.ConclusionsThe development of a network of professionals and associations is the key element to raise awareness of physical activity among transplanted and waiting-for-transplant patients, reducing the pathologies associated with a sedentary lifestyle.  相似文献   

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Camurati-Engelmann disease (CED) is a rare autosomal-dominant skeletal dysplasia caused by mutations in the transforming growth factor-β1 (TGFB1) gene. In this study, a retrospective review of patients with CED evaluated at Peking Union Medical College Hospital in Beijing, China, between November 30, 2000 and November 30, 2020 was conducted. Data including demographic data, manifestations, and examination results were characterized. Furthermore, bone geometry, density, and microarchitecture were assessed and bone strength was estimated by HR-pQCT. Results showed the median age at onset was 2.5 years. Common manifestations included pain in the lower limbs (94%, 17/18), abnormal gait (89%, 16/18), genu valgum (89%, 16/18), reduced subcutaneous fat (78%, 14/18), delayed puberty (73%, 8/11), muscle weakness (67%, 12/18), hearing loss (39%, 7/18), hepatosplenomegaly (39%, 7/18), exophthalmos or impaired vision or visual field defect (33%, 6/18), and anemia (33%, 7/18). Twenty-five percent (4/16) of patients had short stature. Serum level of alkaline phosphatase was elevated in 41% (7/17) of patients whereas beta-C-terminal telopeptide was elevated in 91% of patients (10/11). Among 12 patients, the Z-scores of two patients were greater than 2.5 at the femur neck and the Z-scores of five patients were lower than −2.5 at the femur neck and/or lumbar spine. HR-pQCT results showed lower volumetric BMD (vBMD), altered bone microstructure and lower estimated bone strength at the distal radius and tibia in patients with CED compared with controls. In addition, total volume bone mineral density and cortical volumetric bone mineral density at the radius were negatively correlated with age in patients with CED, but positively correlated with age in controls. In conclusion, the largest case series of CED with characterized clinical features in a Chinese population was reported here. In addition, HR-pQCT was used to investigate bone microstructure at the distal radius and tibia in nine patients with CED, and the alteration of bone density, microstructure, and strength was shown for the first time. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   

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