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Absorptiometry
Kinds of Absorptiometry Selected AbstractsMeasurement of Midfemoral Shaft Geometry: Repeatability and Accuracy Using Magnetic Resonance Imaging and Dual-Energy X-ray AbsorptiometryJOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2001Helen J. Woodhead Abstract Although macroscopic geometric architecture is an important determinant of bone strength, there is limited published information relating to the validation of the techniques used in its measurement. This study describes new techniques for assessing geometry at the midfemur using magnetic resonance imaging (MRI) and dual-energy X-ray absorptiometry (DXA) and examines both the repeatability and the accuracy of these and previously described DXA methods. Contiguous transverse MRI (Philips 1.5T) scans of the middle one-third femur were made in 13 subjects, 3 subjects with osteoporosis. Midpoint values for total width (TW), cortical width (CW), total cross-sectional area (TCSA), cortical cross-sectional area (CCSA), and volumes from reconstructed three-dimensional (3D) images (total volume [TV] and cortical volume [CVol]) were derived. Midpoint TW and CW also were determined using DXA (Lunar V3.6, lumbar software) by visual and automated edge detection analysis. Repeatability was assessed on scans made on two occasions and then analyzed twice by two independent observers (blinded), with intra- and interobserver repeatability expressed as the CV (CV ± SD). Accuracy was examined by comparing MRI and DXA measurements of venison bone (and Perspex phantom for MRI), against "gold standard" measures made by vernier caliper (width), photographic image digitization (area) and water displacement (volume). Agreement between methods was analyzed using mean differences (MD ± SD%). MRI CVs ranged from 0.5 ± 0.5% (TV) to 3.1 ± 3.1% (CW) for intraobserver and 0.55 ± 0.5% (TV) to 3.6 ± 3.6% (CW) for interobserver repeatability. DXA results ranged from 1.6 ± 1.5% (TW) to 4.4 ± 4.5% (CW) for intraobserver and 3.8 ± 3.8% (TW) to 8.3 ± 8.1% (CW) for interobserver variation. MRI accuracy was excellent for TV (3.3 ± 6.4%), CVol (3.5 ± 4.0%), TCSA (1.8 ± 2.6%), and CCSA (1.6 ± 4.2%) but not TW (4.1 ± 1.4%) or CW (16.4 ± 14.9%). DXA results were TW (6.8 ± 2.7%) and CW (16.4 ± 17.0%). MRI measures of geometric parameters of the midfemur are highly accurate and repeatable, even in osteoporosis. Both MRI and DXA techniques have limited value in determining cortical width. MRI may prove valuable in the assessment of surface-specific bone accrual and resorption responses to disease, therapy, and variations in mechanical loading. [source] Weight loss, body fat mass, and leptin in Parkinson's disease,MOVEMENT DISORDERS, Issue 6 2009Birgitta Lorefält RNT Abstract Weight loss is a common problem in Parkinson's disease (PD), but the causative mechanisms behind this weight loss are unclear. We compared 26 PD patients with sex and age matched healthy controls. Examinations were repeated at baseline, after one and after two years. Body fat mass was measured by Dual X-ray Absorptiometry (DXA). Seventy three per cent of the PD patients lost body weight. Loss of body fat mass constituted a considerable part of the loss of body weight. In the patients who lost weight, serum leptin levels were lower than in those who did not lose weight. The relationship between low body fat mass and low leptin levels seems to be relevant, at least for female PD patients. It is reasonable to believe that low leptin levels in these patients could be secondary to the decreased body fat mass. © 2009 Movement Disorder Society [source] Comparison of body fat estimates using 3D digital laser scans, direct manual anthropometry, and DXA in men,,§¶AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2010Todd N. Garlie Objectives: The purpose of this study was to assess the feasibility of utilizing three dimensional whole body laser surface scanning (3DS) to obtain specific anthropometric measurements to estimate percent body fat (BF). Methods: Percent BF estimates from 37 male volunteers, of age 18,62 yr, were determined by inputting manual anthropometric (MA) and 3DS anthropometric measurements into the current Army BF prediction equation for males. The results were compared with each other and to BF values from Dual Energy X-ray Absorptiometry (DXA), employed as a reference method. Results: Mean percent BF estimates (±SD) derived from MA, 3DS and from DXA were 18.4(±3.8), 18.8(±3.9), and 18.9(±4.7), respectively. Analysis of Variance tests revealed no statistical difference between the mean values. Correlation analysis comparing MA and 3DS derived percent BF estimates to each other and to those measured by DXA revealed moderate to strong Pearson correlation coefficients (r), small to moderate standard errors of the estimate (SEE), and were statistically significant (p < 0.05). Conclusions: Correlation coefficients and SEE results for this sample were: (1) DXA vs 3DS; r = 0.74, SEE = 3.2, (2) MA vs DXA; r = 0.82, SEE = 2.8, and (3) MA vs 3DS; r = 0.96, SEE = 1.0. Lin's concordance analysis, including Bland-Altman limits of agreement (LOA), revealed statistically significant measurement agreement among the three measurement modalities (p < 0.05). The application of 3DS scanning to estimate percent BF from commonly used anthropometric measurements are in close agreement with BF estimates derived from analogous MA measurements and from DXA scanning. Am. J. Hum. Biol. 22:695-701, 2010. Published 2010Wiley-Liss, Inc. [source] Minor long-term changes in weight have beneficial effects on insulin sensitivity and ,-cell function in obese subjectsDIABETES OBESITY & METABOLISM, Issue 1 2002A. M. Rosenfalck SUMMARY Aim To evaluate the long-term effect of changes in body composition induced by weight loss on insulin sensitivity (SI), non-insulin mediated glucose disposal, glucose effectiveness (SG) and ,-cell function. Design Glucose metabolism was evaluated before and after participation in a two-year weight loss trial of Orlistat vs. placebo, combined with an energy and fat restricted diet. Subjects Twelve obese patients (11 women, 1 man), age 45.8 ± 10.5 years, body weight (BW) 99.7 ± 13.3 kg, BMI 35.3 ± 2.8 kg/m2. Measurements At inclusion and 2 years later an oral glucose tolerance test (OGTT) and a frequently sampled intravenous glucose tolerance test (FSIGT) were performed. Body composition was estimated by a dual-energy X-ray absorptiometry (DXA) whole body scanning. Results The patients obtained varying changes in BW ranging from a weight loss of 17.8 kg to a weight gain of 6.0 kg. Corresponding changes in fat mass (FM) varied from a 40% reduction to a 19% increase. A significant decrease in both fasting (p =,0.038) and 2 h (p =,0.047) blood glucose at OGTT was found. The improvement in insulin sensitivity (SI) estimated by means of Bergmans Minimal Model, was significantly and linearly correlated to change in total FM (r = , 0.83, p =,0.0026). A multiple regression analysis showed that changes in truncal FM was the strongest predictor of change in SI explaining 67% of the variation. First phase insulin response (AIRg) remained unchanged whereas insulin disposition index increased significantly (p =,0.044). At inclusion five patients had impaired glucose tolerance of which four, who lost weight, were normalized at the retest 2 years later. Conclusion In obese subjects long-term minimal or moderate changes in weight were found to be linearly associated with changes in insulin sensitivity. In obese subjects with impaired glucose tolerance even a minor weight loss was able to normalize glucose tolerance. [source] Calcaneal ultrasonometry in patients with Charcot osteoarthropathy and its relationship with densitometry in the lumbar spine and femoral neck and with markers of bone turnoverDIABETIC MEDICINE, Issue 6 2001A. Jirkovská Abstract Aims To assess calcaneal ultrasonometry in Charcot osteoarthropathy (CO) and to compare it with densitometry measured by dual energy X-ray absorptiometry (DEXA) and with bone remodelling markers. Patients and methods A group of 16 diabetic patients in the acute stage of CO with a mean age (± sd) of 51 ± 13 years was compared with 26 sex- and age-matched control subjects. Both calcaneal quantitative ultrasound (QUS) parameter stiffness and bone mineral density (BMD) measured in lumbar spine and femoral neck by DEXA were compared. Collagen type I cross-linked C-telopeptides (ICTP) were used for assessment of bone resorption. Results Patients with acute CO had significantly lower stiffness of the calcaneus in the Charcot and non-Charcot foot (both P < 0.001) and significantly lower femoral neck BMD (P < 0.05) in comparison with the control group. The T-score of stiffness was significantly lower in the Charcot foot compared with the non-Charcot foot (,3.00 ± 1.39 vs. ,2.36 ± 1.12; P < 0.01) and significantly lower than the mean T-score of BMD in the lumbar spine (,0.57 ± 1.28; P < 0.001) and femoral neck (,1.58 ± 1.24; P < 0.05). A significant difference in ICTP (8.49 ± 4.37 vs. 3.92 ± 2.55 ng/ml; P < 0.001) between patients with CO and the control group was found, and a significant correlation was demonstrated between ICTP and the T-score of stiffness (r = ,0.73; P < 0.01). Conclusion The lower calcaneal QUS parameter stiffness in the Charcot foot in comparison with the control group, with the non-Charcot foot and with BMD in the lumbar spine and femoral neck, and its association with increased bone resorption indicate that calcaneal ultrasonometry may be useful in diagnosing the acute stage of CO and in assessing the risk of foot fracture. Diabet. Med. 18, 495,500 (2001) [source] Normative data of bone mineral density in an unselected adult Austrian populationEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 4 2003S. Kudlacek Abstract Background There is increasing evidence that correct interpretation of bone mineral density (BMD) measurements by dual energy X-ray absorptiometry (DEXA) requires a population-specific reference range. We therefore collected data on age-related BMD in a random sample of the normal adult Austrian population to establish an appropriate normative database. Methods We measured BMD by DEXA at five different skeletal sites in 1089 subjects, i.e. 654 females and 435 males, aged between 21,76 years, who had been recruited by 17 centres across Austria. Results Age-related bone loss was observed until age 65 years with significant changes at the lumbar spine (r = ,0·23), total hip (r = ,0·07), trochanter (r = ,0·10), femoral neck (r = ,0·30) and Ward's triangle (r = ,0·40) in the women but only at the femoral neck (r = ,0·23) and at Ward's triangle (r = ,0·40) in the men. When we calculated T scores from the BMD data of the young normal adult study population and used the T score set points according to the WHO classification of osteopenia and osteoporosis, we found that, depending on the skeletal site measured, 7·6,27·4% of the women and 16,41% of the men in our study group had low bone mass, whereas 0·6,2·7% of the female and 0·2,1·0% of the male study population were osteoporotic. However, osteoporosis was indicated in 4,9-fold more females and 5,15-fold more males when we based our estimates on the normative data provided by the manufacturers of the DEXA systems. Conclusion Our data underscore the importance of using a population-specific reference range for DEXA measurements to avoid overdiagnosis of osteoporosis. [source] Bone mineral density in familial amyloid polyneuropathy and in other neuromuscular disordersEUROPEAN JOURNAL OF NEUROLOGY, Issue 6 2005I. M. Conceição Neuromuscular diseases are a known risk factor for immobilization-induced osteoporosis. The aim of the study was to analyse bone mineral density (BMD) in patients with familial amyloid polyneuropathy (FAP) type I (Val30 Met) and to compare them with a population of patients with other neuromuscular disorders. We studied 24, ambulatory, neuromuscular patients, all men and premenopausal women. We included 12 FAP patients (GI) and 12 patients with other disorders (GII). Clinical data included age, sex, height, weight, alcohol intake, smoking, calcium intake, physical activity and history of fractures. Serum and urinary calcium, osteocalcin, bone alkaline phosphatase, parathyroid hormone, thyroid stimulating hormone and urinary N-telopeptide cross-linked type 1 collagen were determined in all patients. Bone mineral density of lumbar spine, hip and wrist were determined by dual energy X-ray absorptiometry scan. No statistical differences were found in clinical or analytic data between the two groups, except for body mass index and calciuria, which were lower in GI. In GI, 54.5% were osteoporotic, against 23.1% in GII (P = 0.04). Bone mineral density was lower in GI when compared with GII, and tended to decrease with disease duration. Decreased BMI and the early autonomic involvement in GI probably explain the results. The prevention and early treatment of osteoporosis, in FAP patients should be considered a priority. [source] Changes in the bucco-lingual thickness of the mandibular alveolar process and skeletal bone mineral density in dentate women: a 5-yr prospective studyEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2005Grethe Jonasson After tooth extraction there is a great interindividual variation in the remodelling pattern of the alveolar process in edentulous areas, with some individuals losing little bone and others undergoing extensive resorption. However, little is known about possible longitudinal changes in the dentate region of the alveolar process of adults and if these are related to alterations in the skeletal bone mineral density (BMD). In a prospective study, on two occasions, 5-yr apart, the BMD of 117 women was determined in the distal forearm by using dual-energy X-ray absorptiometry, and the bucco-lingual thickness of the mandibular alveolar process was measured on dental casts by using a dial calliper. A decrease in the mean alveolar thickness, exceeding a cut-off value of 0.1 mm, was found in 60% of the women and an increase was found in 3% of the individuals. This decrease was 0.22 ± 0.20 mm in the posterior region and 0.16 ± 0.19 mm in the anterior region. The changes in alveolar thickness in the posterior region were significantly correlated to the BMD changes both on the mid-crestal level site and on the cervical level site. We conclude that the bucco-lingual thickness decreases with age in the dentate alveolar process, possibly owing to periosteal resorption related to skeletal bone loss. [source] Vitamin D receptor FokI genotype influences bone mineral density response to strength training, but not aerobic trainingEXPERIMENTAL PHYSIOLOGY, Issue 4 2005Karma M. Rabon-Stith To determine the influence of the vitamin D receptor (VDR) gene FokI and BsmI genotype on bone mineral density response to two exercise training modalities, 206 healthy men and women (50,81 years old) were studied before and after ,5,6 months of either aerobic exercise training (AT) or strength training (ST). A totla of 123 subjects completed AT (51 men, 72 women) and 83 subjects completed ST (40 men, 43 women). DNA was extracted from blood samples of all subjects and genotyping was performed at the VDR FokI and BsmI locus to determine its association to training response. Total body, greater trochanter and femoral neck bone mineral density (BMD) were measured before and after both training programmes using dual-energy X-ray absorptiometry. VDR BsmI genotype was not significantly related to BMD at baseline or after ST or AT. However, VDR FokI genotype was significantly related to ST- but not AT-induced changes in femoral neck BMD (P < 0.05). The heterozygotes (Ff) in the ST group approached a significantly greater increase in femoral neck BMD (P= 0.058) compared to f homozygotes. There were no significant genotype relationships in the AT group. These data indicate that VDR FokI genotype may influence femoral neck BMD response to ST, but not AT. [source] Physical activity for prevention of osteoporosis in patients with severe haemophilia on long-term prophylaxisHAEMOPHILIA, Issue 3 2010M. KHAWAJI Summary., Physical activity has been considered as an important factor for bone density and as a factor facilitating prevention of osteoporosis. Bone density has been reported to be reduced in haemophilia. To examine the relation between different aspects of physical activity and bone mineral density (BMD) in patients with severe haemophilia on long-term prophylaxis. The study group consisted of 38 patients with severe haemophilia (mean age 30.5 years). All patients received long-term prophylaxis to prevent bleeding. The bone density (BMD g cm,2) of the total body, lumbar spine, total hip, femoral neck and trochanter was measured by dual energy X-ray absorptiometry. Physical activity was assessed using the self-report Modifiable Activity Questionnaire, an instrument which collects information about leisure and occupational activities for the prior 12 months. There was only significant correlation between duration and intensity of vigorous physical activity and bone density at lumber spine L1-L4; for duration (r = 0.429 and P = 0.020) and for intensity (r = 0.430 and P = 0.019); whereas no significant correlation between all aspects of physical activity and bone density at any other measured sites. With adequate long-term prophylaxis, adult patients with haemophilia are maintaining bone mass, whereas the level of physical activity in terms of intensity and duration play a minor role. These results may support the proposition that the responsiveness to mechanical strain is probably more important for bone mass development in children and during adolescence than in adults and underscores the importance of early onset prophylaxis. [source] No significant effect of uridine or pravastatin treatment for HIV lipoatrophy in men who have ceased thymidine analogue nucleoside reverse transcriptase inhibitor therapy: a randomized trial,HIV MEDICINE, Issue 8 2010A Calmy Background Lipoatrophy can complicate thymidine analogue nucleoside reverse transcriptase inhibitor (tNRTI)-based antiretroviral therapy (ART). Lipoatrophy may be less likely with ART including ritonavir-boosted lopinavir (LPV/r). Small, placebo-controlled studies found that uridine (in tNRTI recipients) and pravastatin improved HIV lipoatrophy over 12 weeks. Today, most patients with lipoatrophy receive non-tNRTI-based ART; the effect of uridine in such patients is unknown. Methods We performed a prospective, randomized trial in lipoatrophic adults with plasma HIV RNA<50 HIV-1 RNA copies/mL on tNRTI-sparing ART including LPV/r. Patients received uridine [36 g three times a day (tid) on 10 consecutive days per month; n=10], pravastatin [40 mg every night (nocte); n=12], uridine plus pravastatin (n=11) or neither (n=12) for 24 weeks. The primary endpoint was mean change in limb fat mass as assessed by dual-energy X-ray absorptiometry (DEXA). With 20 patients per intervention, the study had 80% power to detect a mean difference between a treatment and the control of 0.5 kg, assuming a standard deviation of 0.9 and an alpha threshold equal to 5% (two-sided). Results Of 45 participants (all men, with median age 49.5 years and median limb fat 2.6 kg), two discontinued pravastatin and one participant stopped both pravastatin and uridine. The difference between the mean changes in limb fat mass for uridine vs. no uridine was 0.03 kg [95% confidence interval (CI) ,0.35, +0.28; P=0.79]. The respective difference for pravastatin was ,0.03 kg (95% CI ,0.29, +0.34; P=0.84). Pravastatin slightly decreased total cholesterol (0.44 mmol/L; P=0.099). Visceral adipose tissue measured by computed tomography did not change significantly. Conclusion In this population and at the doses used, neither uridine nor pravastatin for 24 weeks significantly increased limb fat mass. [source] A randomized placebo-controlled trial of metformin for the treatment of HIV lipodystrophyHIV MEDICINE, Issue 7 2007R Kohli Objective We conducted a randomized placebo-controlled trial to examine the effects of metformin on visceral adipose tissue (VAT), appendicular fat, lipid profile and insulin sensitivity in HIV-infected persons with central adiposity and mild insulin resistance. Methods Forty-eight HIV-infected men and women with a self-reported increase in abdominal girth and an abnormal waist-to-hip ratio were randomly assigned in double-blind fashion to receive metformin 1500 mg or placebo daily for 24 weeks. Persons with diabetes were excluded. The following measures were obtained at baseline and 24 weeks: single-slice computed tomography (CT) scan, dual-energy X-ray absorptiometry (DEXA), lipid profile and oral glucose tolerance test. Results The median fasting insulin concentration of all participants was 12.3 ,U/mL. The percentage change in VAT was not significantly different between the metformin and placebo groups in univariate analysis and linear regression analysis adjusting for age, height, baseline VAT and insulin area under the curve (10.1% vs 3.2%; P=0.58). Metformin was associated with a significant decrease in appendicular fat mass compared with placebo (,686.0 vs 161.0 g; P=0.03). There was no significant change in lipid profile or insulin sensitivity between the two groups at 24 weeks. Conclusion Metformin should be used with caution in the treatment of HIV lipodystrophy, and, if used, should be reserved for persons with adequate peripheral fat and marked insulin resistance. [source] The prevalence of lipodystrophy in an ambulant HIV-infected population: it all depends on the definitionHIV MEDICINE, Issue 3 2001VM Carter Objectives This study's objective was to determine the prevalence of body shape changes and metabolic abnormalities in an ambulant population with HIV infection. Three different definitions of lipodystrophy were used to assess these changes. Patients' anthropometric measures and dual-energy X-ray absorptiometry (DEXA) scans were compared in order to estimate fat distribution in this population. We sought to evaluate potential predictors for lipodystrophy according to each of the three definitions. Methods We performed a cross-sectional study in the outpatient clinic of a tertiary referral hospital in Melbourne, Australia. We enrolled a total of 167 HIV-infected ambulatory patients over 3 months in mid-1998. Data on 159 males, 149 of whom were receiving triple combination antiretroviral therapy, were evaluated. Anthropometric measures, clinical examination, self-report of body shape changes, biochemical measures and DEXA scan were used to assess lipodystrophy and risk factors for cardiovascular disease. Patients described body shape changes in the face, trunk, arms and legs. Laboratory parameters measured included fasting triglyceride (TG), cholesterol, high-density lipoproteins (HDL), glucose, insulin, CD4 cell count and plasma HIV RNA. Current and past antiretroviral therapies were ascertained. Results According to one proposed Australian national definition of lipodystrophy (LDNC), the prevalence of lipodystrophy in this population was 65%. This definition included an objective assessment with major and minor criteria. Patient-defined lipodystrophy (LDP), which involved a subjective assessment of thinning arms and legs and central adiposity, occurred in 19%. Patient-defined lipoatrophy (LAP), which involved a subjective assessment of thinning arms and legs without central adiposity, occurred in 21.3%. No change in body habitus was noted by 37% of the cohort. Hypercholesterolaemia was recorded in 44%, hypertriglyceridaemia in 52% and elevated insulin levels in 23%. Anthropometry was predictive of the per cent total body fat recorded by DEXA scan, but produced consistently lower values. In multivariate analysis, LDP and LAP were significantly associated with stavudine (d4T) use, while LAP was also associated with zidovudine (ZDV) treatment. There were no treatment associations with LDNC. Protease inhibitor (PI) exposure was associated with metabolic changes but not patient perceived body shape changes, while d4T and ZDV exposure was associated with increased triglycerides and reduced peripheral fat stores. Conclusions The prevalence of body shape changes in a single population varied depending on the definition applied. The LDNC definition overestimated body shape abnormalities in comparison with patient perception. LAP was associated with significantly lower fat stores measured by anthropometry and DEXA scan than those identified under the LDNC definition. In contrast to LDNC, LAP was associated with d4T exposure, nucleoside reverse transcriptase inhibitor (NRTI) and ZDV duration of use, but not PI use. Until a consensus definition for lipodystrophy is developed, including agreement on objective measurement and thresholds for abnormality, careful description of the individual components of the syndrome is required to enable cohort comparisons so that predictors of the syndrome can be assessed more accurately and outcome studies made feasible. [source] Low bone mineral density in children and adolescents with inflammatory bowel disease: A population-based study from Western SwedenINFLAMMATORY BOWEL DISEASES, Issue 12 2009Susanne Schmidt MD Abstract Background: Low bone mineral density (BMD) has been recognized as a potential problem in children with inflammatory bowel disease (IBD). The aim of the study was to investigate BMD in Swedish children and adolescents with IBD and to evaluate possible factors affecting BMD. Methods: To evaluate BMD, all patients (n = 144) underwent a dual-energy X-ray absorptiometry (DXA) of the whole body and the spine. BMD values were expressed as Z-scores using normative pediatric data from Lunar (GE Medical Systems). Results: In this population-based study, the lowest BMD values were found in the lumbar spine. The entire IBD group showed significantly lower BMD Z-scores of the lumbar spine (L2,L4) in comparison to healthy references (,0.8 standard deviation [SD], range ,5.9 to 3.7 SD, P < 0.001). Decreased BMD with a Z-score < ,1 SD occurred in 46.7% of the individuals with Crohn's disease (CD) and in 47.0% of those with ulcerative colitis (UC). Low BMD with a Z-score , ,2 SD was present in 26.7% of the patients with CD and in 24.1% of the UC patients. In a multiple regression model with BMD lumbar spine as the depending variable, possible factors associated with lower BMD were male gender, low body mass index (BMI), and treatment with azathioprine. Conclusions: Low BMD is prevalent in Swedish pediatric patients with IBD. Possible risk factors for lower BMD are male gender, low BMI, and treatment with azathioprine, as a probable marker of disease course severity. (Inflamm Bowel Dis 2009) [source] Sarcopenia is prevalent in patients with Crohn's disease in clinical remissionINFLAMMATORY BOWEL DISEASES, Issue 11 2008Stéphane M. Schneider MD Abstract Background: Patients with Crohn's disease (CD) are prone to osteoporosis. A loss of muscle mass, called sarcopenia, is responsible for an increased risk of disability. Many factors associated with osteopenia also decrease muscle mass. The aim of the present study was to measure the prevalence of sarcopenia in CD patients in remission and uncover its relationship with osteopenia. Methods: In all, 82 CD patients (43 female / 39 male; 36 ± 14 years; body mass index [BMI] 21.1 ± 3.4) and 50 healthy volunteers (30F/20M; 39 ± 13 years; BMI 22.2 ± 2.5) were studied. Body composition was assessed using dual-energy x-ray absorptiometry. Sarcopenia was defined as an appendicular skeletal muscle index (ASMI) below 5.45 kg/m2 for women and 7.26 for men. Osteopenia was defined as a T-score for bone mineral density (BMD) (g/cm2) below ,1.0. Results: In all, 60% of CD patients were found to be sarcopenic and 30% osteopenic, compared to 16% and 4% of controls, respectively (P < 0.01). ASMI was significantly lower in patients than in controls (6.0 ± 1.1 versus 6.5 ± 1.2; P < 0.05). Sarcopenic patients had significantly (P < 0.01) lower BMI (20.0 ± 3.5 versus 22.7 ± 2.8 kg/m2), lean mass (41.5 ± 9.1 versus 48.1 ± 9.1 kg), and BMD (1.09 ± 0.12 versus 1.15 ± 0.08 g/cm2) than nonsarcopenic patients; 91% of sarcopenic patients were also osteopenic. ASMI correlated with BMD (r = 0.46; P < 0.01) and BMI (r = 0.38; P < 0.01). Conclusions: The prevalence of sarcopenia is high in young CD patients and strongly related to osteopenia. These 2 phenomena may share similar mechanisms. Simultaneous screening for sarcopenia and osteopenia may be useful in CD patients. (Inflamm Bowel Dis 2008) [source] Zoledronic acid prevents bone loss after allogeneic haemopoietic stem cell transplantationINTERNAL MEDICINE JOURNAL, Issue 9 2006A. B. D'Souza Abstract Allogeneic haemopoietic stem cell transplant (alloHSCT) patients are at increased risk of osteoporosis. Zoledronic acid (ZA) is a potent i.v. bisphosphonate; however, there are few data on ZA use after alloHSCT. The aim of this study is to examine the effect of a single 4 mg ZA infusion in alloHSCT patients with either osteoporosis (T -score < ,2.5) or rapid bone loss post-alloHSCT. An uncontrolled, prospective study of 12 consecutive patients receiving ZA, predominantly within the first year post-HSCT. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry at the spine and proximal femur pretransplant, pre-ZA and post-ZA. The median annualized percentage change in total hip BMD between the pretransplant scan and the scan immediately before ZA was ,13% (range, ,51 to +3.6%). After ZA treatment, the total hip BMD increased by a median of +3.3% (range, ,20.4 to +14.8%) in 75% of patients. The median annualized percentage change in femoral neck BMD between the pretransplant scan and the scan immediately before ZA was ,13.2% (range, ,40 to +1.0%). Post-ZA, femoral neck BMD increased by a median of +1.4% (range, ,22.2 to +33.6%). Only one patient continued to lose bone from the femoral neck post-ZA infusion. The median annualized percentage change in spinal BMD pretransplant was ,12.5% (range, ,38 to +6.9%). Post-ZA, spinal BMD decreased by a median of ,2.8% (range, ,27.6 to +24.4%). Four patients continued to lose bone from the spine post-ZA. ZA reduces bone loss in most patients after alloHSCT. Our data require confirmation in a larger prospective, randomized study. [source] Proton pump inhibitor omeprazole use is associated with low bone mineral density in maintenance haemodialysis patientsINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 2 2009A. Kirkpantur Summary Objective:, Limited studies have shown that proton pump inhibitor (PPI) therapy may decrease bone density or insoluble calcium reabsorption through induction of hypochlorhydria. However, PPI therapy may also reduce bone resorption via inhibition of osteoclastic vacuolar proton pumps. The aim of this study was to determine whether the opposing effects of PPI therapy may cause clinically important alterations in bone mineral densitometry (BMD) parameters in maintenance haemodialysis patients. Methods:, Sixty-eight maintenance haemodialysis patients were enrolled in this study. Patients were classified into two groups involving users of PPI therapy (omeprazole 20 mg/day, group 1, n = 36 patients) and non-users of acid suppression drugs (group 2, n = 32 patients). Patients had radius, hip and spine BMD assessed by dual-energy X-ray absorptiometry. Results:, The mean duration of PPI therapy with omeprazole was 27 ± 5 months. The users of PPI therapy had lower values of bone mineral density and T -scores at the anatomical regions than non-users of acid suppression drugs. Serum calcium and phosphate levels, calcium-phosphate product and serum intact parathormone levels and the ratio of users of vitamin D therapy were similar among groups. A mutivariable adjusted odds ratio for lower bone density associated with more than 18 months of omeprazole, when all the potential confounders were considered, was 1.31 in the proximal radius, 0.982 in the femur neck, 0.939 in the trochanter and 1.192 in the lumbal spine. Conclusion:, The present data suggest that PPI therapy should be cautiously prescribed in maintenance haemodialysis patients, especially with lower BMD values. [source] Head-to-head comparison of risedronate vs. teriparatide on bone turnover markers in women with postmenopausal osteoporosis: a randomised trialINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 6 2008A. D. Anastasilakis Summary Aims:, We aimed to compare the effect of risedronate (RIS) and teriparatide (TPTD) (recombinant human parathyroid hormone 1,34) on bone turnover markers in women with postmenopausal osteoporosis. Methods:, Forty-four Caucasian women (age 65.1 ± 1.6 years) with postmenopausal osteoporosis were randomly assigned to receive either RIS 35 mg once weekly (n = 22) or TPTD 20 ,g once daily (n = 22) for 12 months. Serum N-terminal propeptide of type 1 collagen (P1NP), C-terminal telopeptide of type 1 collagen (CTx), total alkaline phosphatase (ALP) and intact parathyroid hormone (iPTH) were obtained from all women before, 3 and 6 months after treatment initiation. Lumbar spine bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry before and 12 months after treatment initiation. Results:, P1NP, CTx and total ALP levels decreased in RIS group (p < 0.001) and increased in TPTD group (p < 0.001) throughout the treatment. iPTH increased significantly in RIS group (p < 0.05) and decreased in TPTD group (p < 0.001). Finally, lumbar spine BMD increased significantly in both RIS (p = 0.003) and TPTD groups (p < 0.001) without significant differences between them. Conclusions:, Our data suggest that both serum P1NP and CTx are reliable markers of RIS and TPTD action in women with postmenopausal osteoporosis. In a similar way, serum total ALP can be used as an alternative marker for monitoring both RIS and TPTD action, while iPTH can be used only for TPTD-treated women. The increase in P1NP and CTx after 3 months of treatment with RIS or TPTD can predict the increase in BMD after 12 months of treatment. [source] Quantitative model of cellulite: three-dimensional skin surface topography, biophysical characterization, and relationship to human perceptionINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 4 2005L. K. Smalls Gynoid lipodystrophy (cellulite) is the irregular, dimpled skin surface of the thighs, abdomen, and buttocks in 85% of post-adolescent women. The distinctive surface morphology is believed to result when subcutaneous adipose tissue protrudes into the lower reticular dermis, thereby creating irregularities at the surface. The biomechanical properties of epidermal and dermal tissue may also influence severity. Cellulite-affected thigh sites were measured in 51 females with varying degrees of cellulite, in 11 non-cellulite controls, and in 10 male controls. A non-contact high-resolution three-dimensional (3D) laser surface scanner was used to quantify the skin surface morphology and determine specific roughness values. The scans were evaluated by experts and na,ve judges (n = 62). Body composition was evaluated via dual-energy X-ray absorptiometry; dermal thickness and the dermal,subcutaneous junction were evaluated via high-resolution 3D ultrasound and surface photography under compression. Biomechanical properties were also measured. The roughness parameters Svm (mean depth of the lowest valleys) and Sdr (ratio between the roughness surface area and the area of the xy plane) were highly correlated to the expert image grades and, therefore, designated as the quantitative measures of cellulite severity. The strength of the correlations among na,ve grades, expert grades, and roughness values confirmed that the data quantitatively evaluate the human perception of cellulite. Cellulite severity was correlated to BMI, thigh circumference, percent thigh fat, architecture of the dermal,subcutaneous border (ultrasound surface area, red-band SD from compressed images), compliance, and stiffness (negative correlation). Cellulite severity was predicted by the percent fat and the area of the dermal,subcutaneous border. The biomechanical properties did not significantly contribute to the prediction. Comparison of the parameters for females and males further suggests that percent thigh fat and surface area roughness deviation are the distinguishing features of cellulite. [source] Bone mineral density and bone turnover markers in patients receiving a single course of isotretinoin for nodulocystic acneINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 6 2008Nilgun Solak Tekin Associate Professor Background, High-dose isotretinoin has been reported to have adverse effects on bone mineral density (BMD); however, studies evaluating changes in BMD with isotretinoin therapy at different dosages and with varying treatment durations have produced conflicting results. Objective, To investigate the effect of a standard, single course of isotretinoin therapy on BMD and bone turnover markers in patients with nodulocystic acne. Methods, Thirty-six patients (15 male, 21 female) with severe, recalcitrant, nodulocystic acne and 36 healthy controls (16 male, 20 female) were enrolled in the study. Patients received isotretinoin treatment for 4,6 months until a cumulative dose of 120 mg/kg had been achieved. BMD in the lumbar spine and femur was measured at baseline and at the end of therapy by dual-energy X-ray absorptiometry. Serum calcium, phosphate, parathormone, total alkaline phosphatase, osteocalcin, free deoxypyridinoline, and urinary calcium were also measured before and at the end of treatment. Results, No significant differences were found in lumbar spine and femoral BMD between the patient and control groups at the beginning of the study (P > 0.05), and no statistically significant difference was observed between the BMD values in patients at the beginning vs. the end of treatment (P > 0.05). No statistically significant difference in bone turnover markers was found between patients and controls at the beginning of the study (P > 0.05), and no statistically significant changes in bone turnover markers were observed in patients at the beginning vs. the end of treatment (P > 0.05). Conclusion, A single course of isotretinoin therapy has no clinically significant effect on bone metabolism. [source] Screening for osteoporosis in anorexia nervosa: Prevalence and predictors of reduced bone mineral densityINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 3 2008Anthony P. Winston MRCPsych Abstract Objective: Decreased bone mineral density (BMD) in anorexia nervosa (AN) can be detected easily by dual-energy X-ray absorptiometry (DXA). This study was designed to assess the prevalence of osteoporosis and osteopenia in AN, identify predictors, and determine the diagnostic yield of screening with DXA. Method: DXA was used to screen 59 unselected adult patients with a history of AN. Results: Osteoporosis was identified in 18 patients (31%) and osteopenia in 30 (51%). The spine had a lower mean T -score than either the hip or femur. BMI significantly predicted T -score (p = 0.0006) and the odds of having osteoporosis (p = 0.0188). There was a significant association between use of oestrogens and the presence of osteoporosis or osteopenia (p = 0.0491). There was no significant association between duration of AN and T -score. A duration of AN of less than 1 year was found in 12% of those with osteoporosis. Conclusion: BMI is a strong predictor of BMD in AN. DXA is an effective screening tool and should probably be offered routinely. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord, 2008 [source] The frequency of low bone mineral density and its associated risk factors in patients with inflammatory bowel diseasesINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 3 2010Yasser EZZAT Abstract Objective:, To detect the frequency and the predictive factors of low bone mineral density in inflammatory bowel disease (IBD) patients, so as to optimize bone mineral density (BMD) monitoring and treatment for those at risk. Subjects and methods:, Thirty Asian patients were included in this study and were divided into 18 patients with ulcerative colitis (UC), and 12 patients with Crohn's disease (CD). All patients were diagnosed by colonoscopy and histopathological biopsy and were subjected to routine laboratory investigations in addition to 25 hydroxy vitamin D levels as well as serum calcium, phosphorus and alkaline phosphatise. BMD was measured by using dual-energy X-ray absorptiometry (DEXA) scan at lumbar spine and femoral neck; predictive factors for BMD were analyzed by group comparison and step-wise regression analysis. Results:, There was increased frequency of osteoporosis and osteopenia involving the lumbar spine in patients with IBD being more common among CD patients than in the UC group. Positive correlations were found between low BMD measurements and vitamin D levels, body mass index (BMI) (P < 0.001) as well as steroid cumulative dose and duration of therapy (P < 0.001); stepwise regression analysis showed that CD and vitamin D deficiency are predictive factors for both osteoporosis and osteopenia (P = 0.024, P = 0.027, respectively). Conclusion:, Low BMD was found to be more frequent among patients with CD than UC; in addition CD and vitamin D deficiency act as predictive factors for low BMD. We recommend that calcium and vitamin D should be given to all IBD patients; in addition, bisphosphonate administration should be put into consideration. [source] Prevalence and predictors of osteoporosis and the impact of life style factors on bone mineral densityINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 3 2007Abdulbari BENER Abstract Aim:, The aim of this study was to determine the prevalence and predictors of osteoporosis and the impact of life style factors on bone mineral density (BMD) in premenopausal and postmenopausal Qatari women. Methods:, This is a cross-sectional study. A total of 821 healthy Qatari women aged 20,70 years had given consent and participated and the study was conducted from June 2005 to December 2006 at the Rumaillah Hospital, Hamad Medical Corporation (HMC), Doha, State of Qatar. All subjects completed a questionnaire on reproductive and life style factors. Height and weight were measured. All subjects underwent dual-energy X-ray absorptiometry (DXA) to determine factors influencing BMD of the spine and femur. The main outcome measures were menopausal status, socio-demographic and lifestyle factors and BMD measurements. Results:, The prevalence of osteoporosis in postmenopausal women was 12.3%. BMI was significantly higher among postmenopausal women (P < 0.001) when compared to premenopausal women. The subjects who regularly consumed dairy products had better BMD at spine, neck and ward sites (P < 0.05). Those doing regular household work for 3,4 h a week had higher BMD at all sites compared to those who did not do their own household work. Multiple regression analysis showed that education level and body mass index were strong positive predictors showing high significance. Conclusion:, The relation between lifestyle and BMD were explored in Qatari women. The prevalence of osteoporosis in Qatari women is comparable to other countries. BMD values were higher in women who were taking diary products regularly, and were involved with household work. [source] Calcium supplement necessary to correct hypocalcemia after total parathyroidectomy for renal osteodystrophyINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2000Masayuki Nakagawa Abstract Background: Prediction of the extent of calcium supplement will facilitate safe and efficient management of hypocalcemia in the early postoperative stage of total parathyroidectomy with autotransplantation (PTXa) in patients with renal osteodystrophy. Methods: The correlation between the extent of calcium deficiency, estimated by the amount of calcium supplement over 48 h after PTXa and using various parameters such as carboxy terminal parathyroid hormone (c-PTH), intact PTH (i-PTH), alkaline phosphatase (ALP), serum calcium, serum phosphorus, duration of hemodialysis, total weight of resected parathyroid glands and degree of subperiosteal resorption of the middle phalanx was examined in 49 patients who underwent PTX with subcutaneous autotransplantation. Bone mineral density (BMD) was also determined before, 3 months and 1 year after PTXa with dual energy X-ray absorptiometry (DEXA) in 13 patients. Results: There was a positive correlation between pre-operative i-PTH level (r = 0.56, P < 0.0005) or ALP level (r = 0.50, P < 0.0005) and the amount of calcium supplement over 48 h after PTXa in these patients. Furthermore, the degree of subperiosteal resorption, determined by Jensen's classification, was significantly correlated with the amount of calcium supplement after PTX (P < 0.05). Bone mineral density 3 months after (P < 0.0005) and 1 year after PTXa (P < 0.001) significantly increased compared with BMD before PTXa in all patients examined. Conclusion: These findings suggest that the pre-operative determination of i-PTH, ALP levels and degree of subperiosteal resorption allow the management of hypocalcemia safely and efficiently in renal osteodystrophy patients after PTXa. [source] Association Between Fitness and Changes in Body Composition and Muscle StrengthJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2010George A. Kuchel, [see editorial comments by Drs. Gustavo Duque, pp 37 OBJECTIVES: To examine the association between physical fitness, assessed according to ability and time to complete a 400-m walk, on changes in body composition and muscle strength over a 7-year period. DESIGN: Prospective observational cohort study. SETTING: Memphis, Tennessee, and Pittsburgh, Pennsylvania. PARTICIPANTS: Two thousand nine hundred forty-nine black and white men and women aged 70 to 79 participating in the Health, Aging and Body Composition Study. MEASUREMENTS: Body composition (fat and bone-free lean mass) was assessed using dual-energy X-ray absorptiometry in Years 1 to 6 and 8. Knee extension strength was measured using isokinetic dynamometry and grip strength using isometric dynamometry in Years 1, 2, 4, 6, and 8. RESULTS: Less fit people weighed more and had a higher total percentage of fat and a lower total percentage of lean mass than very fit men and women at baseline (P<.001). Additionally, the least fit lost significantly more weight, fat mass, and lean mass over time than the very fit (all P<.01). Very fit people had the highest grip strength and knee extensor strength at baseline and follow-up; decline in muscle strength was similar in every fitness group. CONCLUSION: Low fitness in old age was associated with greater weight loss and loss of lean mass than with high fitness. Despite having lower muscle strength, the rate of decline in the least fit persons was similar to that in the most fit. In clinical practice, a long-distance walk test as a measure of fitness might be useful to identify people at risk for these adverse health outcomes. [source] Association Between Changes in Habitual Physical Activity and Changes in Bone Density, Muscle Strength, and Functional Performance in Elderly Men and WomenJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 12 2008Robin M. Daly PhD OBJECTIVES: To investigate the long-term effects of habitual physical activity on changes in musculoskeletal health, functional performance, and fracture risk in elderly men and women. DESIGN: Ten-year prospective population-based study. SETTING: Malmö-Sjöbo Prospective Study, Sweden. PARTICIPANTS: Participants were 152 men and 206 women aged 50, 60, 70, and 80 who were followed for 10 years. MEASUREMENTS: Distal radius bone mineral density (BMD) (single photon absorptiometry), upper limb muscle (grip) strength, balance, gait velocity, occupational and leisure-time activity, and fractures (interview-administered questionnaire) were reassessed after 10 years. Annual changes for all measures were compared between participants with varying habitual physical activity histories at baseline and follow-up: inactive,inactive (n=202), active,inactive (n=47), inactive,active (n=49), and active,active (n=60). Data for men and women were pooled, because there were no sex-by-activity group interactions. To detect possible differences in fracture incidence between the varying habitual activity groups, participants were classified into two activity groups based on their activity classification at baseline and follow-up: inactive:less active versus active:more active. RESULTS: The annual rate of bone loss was 0.6% per year less in individuals classified as active at both time points than in those classified as inactive at both time points (P<.01). Similar results were observed for balance, but there was no effect of varying habitual activity on changes in muscle strength or gait velocity. There were also no differences in fracture incidence between individuals categorized as active:more active and those categorized as inactive:less active during the follow-up (adjusted hazard ratio=0.90, 95% confidence interval (CI)=0.42,1.90). CONCLUSION: This study showed that elderly men and women who maintained a habitually active lifestyle over 10 years had lower bone loss and retained better balance than those who remained habitually inactive. [source] Changes in Muscle Mass, Muscle Strength, and Power but Not Physical Function Are Related to Testosterone Dose in Healthy Older MenJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 11 2008Thomas W. Storer PhD OBJECTIVES: To examine the effect of graded doses of testosterone on physical function and muscle performance in healthy, older men. DESIGN: Randomized, double-blind, placebo-controlled clinical trial. SETTING: General clinical research center. PARTICIPANTS: Community-dwelling healthy men aged 60 to 75 (N=44). INTERVENTION: Monthly treatment with a gonadotropin-releasing hormone agonist plus 25, 50, 125, or 300 mg/wk of intramuscular injections of testosterone enanthate for 20 weeks. MEASUREMENTS: Skeletal muscle mass (SMM) was estimated using dual-energy X-ray absorptiometry. Leg press strength was measured by one repetition maximum, leg power by Nottingham Leg Rig, and muscle fatigability by repetitions to failure in the leg press exercise. Stair climbing, 6-meter and 400-meter walking speed, and a timed-up-and-go (TUG) test were used to assess physical function. RESULTS: Significant testosterone dose- and concentration-dependent increases were observed in SMM (P<.001) and maximal strength (P=.001) but not muscle fatigability. Leg power also increased dose-dependently (P=.048). In contrast, changes in self-selected normal and fast walking speed over 6 or 400 meters, stair climbing power, and time for the TUG were not significantly related to testosterone dose, testosterone concentrations, or changes in muscle strength or power, or SMM. CONCLUSION: Testosterone administration was associated with dose-dependent increases in SMM, leg strength, and power but did not improve muscle fatigability or physical function. The observation that physical function scores did not improve linearly with strength suggests that these high-functioning older men were already in the asymptotic region of the curve describing the relationship between physical function and strength. [source] Functional Impact of Relative Versus Absolute Sarcopenia in Healthy Older WomenJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 11 2007Marcos Estrada MD OBJECTIVES: To determine whether adjustment of muscle mass for height2 or for body mass represents a more-relevant predictor of physical performance. DESIGN: Cross-sectional study, using baseline data from a trial comparing upper- and lower-body training. SETTING: Women recruited from the community and gynecological practices in Connecticut. PARTICIPANTS: One hundred eighty-nine healthy older (aged 67.5 ± 4.8), active women receiving estrogen for osteoporosis over 2 years. MEASUREMENTS: Total and appendicular skeletal muscle (ASM) and fat mass (AFM) were determined using dual x-ray absorptiometry. Physical performance, muscle strength, and fitness measures were obtained at baseline. RESULTS: Adjusting ASM for height2 identifies lean women who are sarcopenic according to published standards yet fails to identify overweight and obese women whose ASM adjusted for body mass is low. ASM divided by body mass (ASM/body mass) is a stronger physical performance predictor, explaining 32.5%, 13.5%, 11.6%, 6.3%, and 6.8% of the variance in maximum time on treadmill, 6-minute walk, gait speed, 8-foot walk, and single leg stance, respectively, whereas ASM divided by height in m2 (ASM/height2) explained only 2.9%, 0.2%, 2.0%, 0.04%, and 0.1%. Multivariate modeling demonstrated considerable overlap in aspects of ASM/body mass and AFM/body mass associated with performance, with ASM/body mass dominant. In contrast, ASM/height2 is a much stronger predictor of leg press 1 repetition maximum and maximum power. CONCLUSION: The results suggest that relative sarcopenia with ASM adjusted for body mass is a better mobility predictor, with absolute sarcopenia a better indicator of isolated muscle group function in healthy postmenopausal women receiving estrogen replacement. [source] Kidney Function as a Predictor of Loss of Lean Mass in Older Adults: Health, Aging and Body Composition StudyJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 10 2007Linda F. Fried MD OBJECTIVES: To assess the association between kidney function and change in body composition in older individuals. DESIGN: Prospective cohort study. SETTING: Two sites, Pittsburgh, Pennsylvania, and Memphis, Tennessee. PARTICIPANTS: Three thousand twenty-six well-functioning, participants aged 70 to 79 in the Health, Aging and Body Composition Study. MEASUREMENTS: Body composition (bone-free lean mass and fat mass) was measured using dual x-ray absorptiometry annually for 4 years. Kidney function was measured at baseline according to serum creatinine (SCr). Comorbidity and inflammatory markers were evaluated as covariates in mixed-model, repeated-measures analysis. RESULTS: High SCr was associated with loss of lean mass in men but not women, with a stronger relationship in black men (P=.02 for difference between slopes for white and black men). In white men, after adjustment for age and comorbidity, higher SCr remained associated with loss of lean mass (,0.07±0.03 kg/y greater loss per 0.4 mg/dL (1 standard deviation (SD)), P=.009) but was attenuated after adjustment for inflammatory factors (,0.05±0.03 kg/y greater loss per SD, P=.10). In black men, the relationship between SCr and loss of lean mass (,0.19±0.04 kg/y per SD, P<.001) persisted after adjustment for inflammation and overall weight change. CONCLUSION: Impaired kidney function may contribute to loss of lean mass in older men. Inflammation appeared to mediate the relationship in white but not black men. Future studies should strive to elucidate mechanisms linking kidney disease and muscle loss and identify treatments to minimize loss of lean mass and its functional consequences. [source] Resting energy expenditure and body composition of Labrador Retrievers fed high fat and low fat dietsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5-6 2006S. Yoo Summary A high dietary fat intake may be an important environmental factor leading to obesity in some animals. The mechanism could be either an increase in caloric intake and/or a decrease in energy expenditure. To test the hypothesis that high fat diets result in decreased resting energy expenditure (REE), we measured REE using indirect calorimetry in 10-adult intact male Labrador Retrievers, eating weight-maintenance high-fat (HF, 41% energy, average daily intake: 8018 ± 1247 kJ/day, mean ± SD) and low-fat (LF, 14% energy, average daily intake: 7331 ± 771 kJ/day) diets for a 30-day period. At the end of each dietary treatment, body composition measurements were performed using dual-energy X-ray absorptiometry. The mean ± SD REE was not different between diets (4940 ± 361 vs. 4861 ± 413 kJ/day on HF and LF diets respectively). Measurements of fat-free mass (FFM) and fat mass (FM) also did not differ between diets (FFM: 26.8 ± 2.3 kg vs. 26.3 ± 2.5 kg; FM: 3.0 ± 2.3 vs. 3.1 ± 1.5 kg on HF and LF diets respectively). In summary, using a whole body calorimeter, we found no evidence of a decrease in REE or a change in body composition on a HF diet compared with LF diet. 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