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Claes Ohlsson - One of the best experts on this subject based on the ideXlab platform.
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Exercise During Growth and Young Adulthood Is Independently Associated With Cortical Bone Size and Strength in Old Swedish Men
Journal of Bone and Mineral Research, 2014Co-Authors: Martin Nilsson, Magnus K Karlsson, Claes Ohlsson, Dan Mellström, Daniel Sundh, Mattias LorentzonAbstract:Previous studies have reported an association between exercise during youth and increased areal Bone mineral density at old age. The primary aim of this study was to investigate if exercise during growth was independently associated with greater cortical Bone Size and whole Bone strength in weight-bearing Bone in old men. The tibia and radius were measured using both peripheral quantitative computed tomography (pQCT) (XCT-2000; Stratec) at the diaphysis and high-resolution pQCT (HR-pQCT) (XtremeCT; Scanco) at the metaphysis to obtain cortical Bone geometry and finite element-derived Bone strength in distal tibia and radius, in 597 men, 79.9 +/- 3.4 (mean +/- SD) years old. A self-administered questionnaire was used to collect information about previous and current physical activity. In order to determine whether level of exercise during growth and young adulthood or level of current physical activity were independently associated with Bone parameters in both tibia and radius, analysis of covariance (ANCOVA) analyses were used. Adjusting for covariates and current physical activity, we found that men in the group with the highest level of exercise early in life (regular exercise at a competitive level) had higher tibial cortical cross-sectional area (CSA; 6.3%, p
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The Role of GH/IGF-I-Mediated Mechanisms in Sex Differences in Cortical Bone Size in Mice
Calcified Tissue International, 2011Co-Authors: Lisa E. Olson, Claes Ohlsson, Subburaman MohanAbstract:Cortical Bone dimensions are important determinants of Bone strength. Gender differences in cortical Bone Size caused by greater periosteal expansion in males than in females during the pubertal growth spurt are well established both in humans and in experimental animal models. However, the mechanism by which gender influences cortical Bone Size is still a matter of investigation. The role of androgens and estrogen in pubertal Bone growth has been examined in human disorders as well as animal models, such as gonadectomized or sex steroid receptor knockout mice. Based on the findings that growth hormone (GH) and insulin-like growth factor I (IGF-I) are major regulators of postnatal skeletal growth, we and others have predicted that sex hormones interact with the GH/IGF-I axis to regulate cortical Bone Size. However, studies conflict as to whether estrogen and androgens impact cortical Bone Size through the canonical pathway, through GH without IGF-I mediation, through IGF-I without GH stimulation, or independent of GH/IGF-I. We review recent data on the impact of sex steroids and components of the GH/IGF axis on sexual dimorphism in Bone Size. While the GH/IGF-I axis is a major player in regulating peak Bone Size, the relative contribution of GH/IGF-dependent mechanisms to sex differences in cortical Bone Size remains to be established.
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previous sport activity during childhood and adolescence is associated with increased cortical Bone Size in young adult men
Journal of Bone and Mineral Research, 2009Co-Authors: Martin Nilsson, Claes Ohlsson, Dan Mellström, Mattias LorentzonAbstract:Physical activity during growth has been associated with altered cortical Bone geometry, but it remains uncertain if the physical activity–induced increments in cortical Bone Size remain when the level of physical activity is diminished or ceased. The aim of this study was to investigate if physical activity during growth is associated with cortical Bone geometry in currently inactive young men. In this study, 1068 men (18.9 ± 0.6 [SD] yr) were included. Cortical Bone geometry at the tibia and radius were measured using pQCT. A standardized questionnaire was used to collect information about current and previous sport activity. Subjects who continued to be active (n = 678) and who had been previously active (n = 285) in sports had a wider cortical Bone (periosteal circumference [PC], 4.5% and 3.2%, respectively) with increased cross-sectional area (CSA; 12.5% and 6.9%) of the tibia than the always inactive subjects (n = 82). In the currently inactive men (n = 367), regression analysis (including covariates age, height, weight, calcium intake, smoking, and duration of inactivity) showed that previous sport activity was independently associated with cortical Bone Size of the tibia (CSA and PC). Amount of previous sport activity explained 7.3% of the total variation in cortical CSA. Subjects, who ceased their sport activity for up to 6.5 yr previously, still had greater cortical PC and CSA of the tibia than always inactive subjects. The results from this study indicate that sport activity during growth confers positive effects on Bone geometry even though sport activity is ceased.
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Sex steroid levels and cortical Bone Size in young men are associated with a uridine diphosphate glucuronosyltransferase 2b7 polymorphism (H268Y)
The Journal of Clinical Endocrinology and Metabolism, 2007Co-Authors: Charlotte Swanson, Mattias Lorentzon, Liesbeth Vandenput, Fernand Labrie, Anders Rane, Jenny Jakobsson, Sarah Chouinard, Alain Bélanger, Claes OhlssonAbstract:CONTEXT: Sex steroids are involved in the regulation of pubertal cortical Bone expansion in males. In vitro studies have indicated that the enzyme uridine diphosphate glucuronosyltransferase (UGT) 2B7 has the capacity to glucuronidate sex steroids and their metabolites. OBJECTIVE: Our objective was to determine the impact of the H(268)Y polymorphism in the UGT2B7 gene on interindividual variation of serum levels of sex steroids and cortical Bone dimensions. PARTICIPANTS: The population-based cohort Gothenburg Osteoporosis and Obesity Determinants study consists of 1068 young adult Swedish men (age 18.9 yr). MAIN OUTCOME MEASURES: Serum levels of sex steroids and the three major glucuronidated androgen metabolites, androstane-3alpha,17beta-diol-17glucuronide, androstane-3alpha,17beta-diol-3glucuronide, and androsterone-glucuronide, were analyzed. Cortical and trabecular volumetric Bone mineral density and cortical Bone Size were measured by peripheral quantitative computer tomography. RESULTS: Serum levels of testosterone (YY 9% over HH; P < 0.01), dihydrotestosterone (YY 10% over HH; P < 0.01), and estradiol (YY 8% over HH; P < 0.01) were associated with the UGT2B7 H(268)Y polymorphism. The polymorphism was associated with androstane-3alpha,17beta-diol-17glucuronide and androstane-3alpha,17beta-diol-3glucuronide (P < 0.01), but not with androsterone-glucuronide serum levels. In addition, the UGT2B7 H(268)Y polymorphism was an independent predictor of cortical Bone Size, reflected by periosteal circumference and cortical moment of inertia (P < 0.01), in both the weight-bearing tibia and nonweight-bearing radius. CONCLUSIONS: The UGT2B7 H(268)Y polymorphism is independently associated with cortical Bone Size and serum sex steroid levels in young adult men. Subjects homozygous for the Y allele had higher serum testosterone and larger cortical Bone Size than subjects homozygous for the H allele. However, the underlying mechanism behind these associations is unknown and has to be studied further.
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leptin is a negative independent predictor of areal bmd and cortical Bone Size in young adult swedish men
Journal of Bone and Mineral Research, 2006Co-Authors: Mattias Lorentzon, Dan Mellström, Kerstin Landin, Claes OhlssonAbstract:The association between leptin and areal BMD has been controversial, and the predictive role of leptin on cortical volumetric BMD and Bone Size has not previously been studied. We show that leptin is a negative independent predictor of aBMD (DXA), at several measured sites, and of cortical Bone Size (pQCT) in a large population of young men. Introduction: Recent findings suggest that both adipose tissue (AT) and Bone mass are regulated by leptin. Previous reports studying the association between leptin and areal BMD (aBMD) have yielded conflicting results. The role of leptin on volumetric BMD (vBMD) and Bone Size of the cortical and trabecular Bone compartments has not previously been studied. Materials and Methods: The Gothenburg Osteoporosis and Obesity Determinants (GOOD) study is a population-based study of 1068 men (age, 18.9 ± 0.6 [SD] years). aBMD of the total body, lumbar spine, femoral neck, both radii, and trochanter, as well as total body AT and lean mass (LM) were measured using DXA, whereas cortical and trabecular vBMD and Bone Size were measured by pQCT. Results: Total body LM could explain a larger magnitude of the difference in the variation in aBMD and cortical Bone Size than what total body AT could (total body aBMD: LM 37.4% versus AT 8.7%; tibia cross-sectional area [CSA]: LM 46.8% versus AT 5.6%). The independent role of leptin on Bone parameters was studied using a multiple linear regression model, including age, total body LM and AT, height, present physical activity, calcium intake, and smoking as covariates. Leptin was found to be a negative independent predictor of aBMD (total body: β =−0.08, p =0.01; lumbar spine: β =−0.13, p < 0.01; trochanter: β =−0.09, p =0.01), as well as of the cortical Bone Size (CSA and thickness) of both the radius (CSA: β =−0.12, p < 0.001) and tibia (CSA: β =−0.08, p < 0.01), but not of the cortical or trabecular vBMD of these Bones. Conclusion: Our results indicate that LM has a greater impact on Bone mass than AT. Our findings further show that leptin is a negative independent predictor of aBMD at several measured sites and of Bone parameters reflecting cortical Bone Size, but not vBMD, in a large population of young Swedish men.
Mattias Lorentzon - One of the best experts on this subject based on the ideXlab platform.
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Exercise During Growth and Young Adulthood Is Independently Associated With Cortical Bone Size and Strength in Old Swedish Men
Journal of Bone and Mineral Research, 2014Co-Authors: Martin Nilsson, Magnus K Karlsson, Claes Ohlsson, Dan Mellström, Daniel Sundh, Mattias LorentzonAbstract:Previous studies have reported an association between exercise during youth and increased areal Bone mineral density at old age. The primary aim of this study was to investigate if exercise during growth was independently associated with greater cortical Bone Size and whole Bone strength in weight-bearing Bone in old men. The tibia and radius were measured using both peripheral quantitative computed tomography (pQCT) (XCT-2000; Stratec) at the diaphysis and high-resolution pQCT (HR-pQCT) (XtremeCT; Scanco) at the metaphysis to obtain cortical Bone geometry and finite element-derived Bone strength in distal tibia and radius, in 597 men, 79.9 +/- 3.4 (mean +/- SD) years old. A self-administered questionnaire was used to collect information about previous and current physical activity. In order to determine whether level of exercise during growth and young adulthood or level of current physical activity were independently associated with Bone parameters in both tibia and radius, analysis of covariance (ANCOVA) analyses were used. Adjusting for covariates and current physical activity, we found that men in the group with the highest level of exercise early in life (regular exercise at a competitive level) had higher tibial cortical cross-sectional area (CSA; 6.3%, p
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previous sport activity during childhood and adolescence is associated with increased cortical Bone Size in young adult men
Journal of Bone and Mineral Research, 2009Co-Authors: Martin Nilsson, Claes Ohlsson, Dan Mellström, Mattias LorentzonAbstract:Physical activity during growth has been associated with altered cortical Bone geometry, but it remains uncertain if the physical activity–induced increments in cortical Bone Size remain when the level of physical activity is diminished or ceased. The aim of this study was to investigate if physical activity during growth is associated with cortical Bone geometry in currently inactive young men. In this study, 1068 men (18.9 ± 0.6 [SD] yr) were included. Cortical Bone geometry at the tibia and radius were measured using pQCT. A standardized questionnaire was used to collect information about current and previous sport activity. Subjects who continued to be active (n = 678) and who had been previously active (n = 285) in sports had a wider cortical Bone (periosteal circumference [PC], 4.5% and 3.2%, respectively) with increased cross-sectional area (CSA; 12.5% and 6.9%) of the tibia than the always inactive subjects (n = 82). In the currently inactive men (n = 367), regression analysis (including covariates age, height, weight, calcium intake, smoking, and duration of inactivity) showed that previous sport activity was independently associated with cortical Bone Size of the tibia (CSA and PC). Amount of previous sport activity explained 7.3% of the total variation in cortical CSA. Subjects, who ceased their sport activity for up to 6.5 yr previously, still had greater cortical PC and CSA of the tibia than always inactive subjects. The results from this study indicate that sport activity during growth confers positive effects on Bone geometry even though sport activity is ceased.
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Sex steroid levels and cortical Bone Size in young men are associated with a uridine diphosphate glucuronosyltransferase 2b7 polymorphism (H268Y)
The Journal of Clinical Endocrinology and Metabolism, 2007Co-Authors: Charlotte Swanson, Mattias Lorentzon, Liesbeth Vandenput, Fernand Labrie, Anders Rane, Jenny Jakobsson, Sarah Chouinard, Alain Bélanger, Claes OhlssonAbstract:CONTEXT: Sex steroids are involved in the regulation of pubertal cortical Bone expansion in males. In vitro studies have indicated that the enzyme uridine diphosphate glucuronosyltransferase (UGT) 2B7 has the capacity to glucuronidate sex steroids and their metabolites. OBJECTIVE: Our objective was to determine the impact of the H(268)Y polymorphism in the UGT2B7 gene on interindividual variation of serum levels of sex steroids and cortical Bone dimensions. PARTICIPANTS: The population-based cohort Gothenburg Osteoporosis and Obesity Determinants study consists of 1068 young adult Swedish men (age 18.9 yr). MAIN OUTCOME MEASURES: Serum levels of sex steroids and the three major glucuronidated androgen metabolites, androstane-3alpha,17beta-diol-17glucuronide, androstane-3alpha,17beta-diol-3glucuronide, and androsterone-glucuronide, were analyzed. Cortical and trabecular volumetric Bone mineral density and cortical Bone Size were measured by peripheral quantitative computer tomography. RESULTS: Serum levels of testosterone (YY 9% over HH; P < 0.01), dihydrotestosterone (YY 10% over HH; P < 0.01), and estradiol (YY 8% over HH; P < 0.01) were associated with the UGT2B7 H(268)Y polymorphism. The polymorphism was associated with androstane-3alpha,17beta-diol-17glucuronide and androstane-3alpha,17beta-diol-3glucuronide (P < 0.01), but not with androsterone-glucuronide serum levels. In addition, the UGT2B7 H(268)Y polymorphism was an independent predictor of cortical Bone Size, reflected by periosteal circumference and cortical moment of inertia (P < 0.01), in both the weight-bearing tibia and nonweight-bearing radius. CONCLUSIONS: The UGT2B7 H(268)Y polymorphism is independently associated with cortical Bone Size and serum sex steroid levels in young adult men. Subjects homozygous for the Y allele had higher serum testosterone and larger cortical Bone Size than subjects homozygous for the H allele. However, the underlying mechanism behind these associations is unknown and has to be studied further.
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leptin is a negative independent predictor of areal bmd and cortical Bone Size in young adult swedish men
Journal of Bone and Mineral Research, 2006Co-Authors: Mattias Lorentzon, Dan Mellström, Kerstin Landin, Claes OhlssonAbstract:The association between leptin and areal BMD has been controversial, and the predictive role of leptin on cortical volumetric BMD and Bone Size has not previously been studied. We show that leptin is a negative independent predictor of aBMD (DXA), at several measured sites, and of cortical Bone Size (pQCT) in a large population of young men. Introduction: Recent findings suggest that both adipose tissue (AT) and Bone mass are regulated by leptin. Previous reports studying the association between leptin and areal BMD (aBMD) have yielded conflicting results. The role of leptin on volumetric BMD (vBMD) and Bone Size of the cortical and trabecular Bone compartments has not previously been studied. Materials and Methods: The Gothenburg Osteoporosis and Obesity Determinants (GOOD) study is a population-based study of 1068 men (age, 18.9 ± 0.6 [SD] years). aBMD of the total body, lumbar spine, femoral neck, both radii, and trochanter, as well as total body AT and lean mass (LM) were measured using DXA, whereas cortical and trabecular vBMD and Bone Size were measured by pQCT. Results: Total body LM could explain a larger magnitude of the difference in the variation in aBMD and cortical Bone Size than what total body AT could (total body aBMD: LM 37.4% versus AT 8.7%; tibia cross-sectional area [CSA]: LM 46.8% versus AT 5.6%). The independent role of leptin on Bone parameters was studied using a multiple linear regression model, including age, total body LM and AT, height, present physical activity, calcium intake, and smoking as covariates. Leptin was found to be a negative independent predictor of aBMD (total body: β =−0.08, p =0.01; lumbar spine: β =−0.13, p < 0.01; trochanter: β =−0.09, p =0.01), as well as of the cortical Bone Size (CSA and thickness) of both the radius (CSA: β =−0.12, p < 0.001) and tibia (CSA: β =−0.08, p < 0.01), but not of the cortical or trabecular vBMD of these Bones. Conclusion: Our results indicate that LM has a greater impact on Bone mass than AT. Our findings further show that leptin is a negative independent predictor of aBMD at several measured sites and of Bone parameters reflecting cortical Bone Size, but not vBMD, in a large population of young Swedish men.
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Polymorphisms in the aromatase gene predict areal BMD as a result of affected cortical Bone Size: the GOOD study.
Journal of Bone and Mineral Research, 2005Co-Authors: Mattias Lorentzon, Charlotte Swanson, Anna-lena Eriksson, Dan Mellström, Claes OhlssonAbstract:The association between aromatase gene polymorphisms, Bone parameters, and sex steroid levels was studied in 1068 men (18.9 ± 0.6 years of age). Several aromatase gene polymorphisms were found to be associated with serum testosterone levels and cortical Bone Size but not with trabecular volumetric BMD. Introduction: Both testosterone and estrogens are important for the male skeleton. Aromatase, the product of the CYP19 gene, is the key enzyme in the conversion of testosterone to estradiol. A functional aromatase enzyme has been shown to be crucial for the normal development of the male skeleton. The role of genetic polymorphisms in the aromatase gene for trabecular volumetric BMD (vBMD) and cortical Bone Size has not previously been studied in men. Materials and Methods: The Gothenburg Osteoporosis and Obesity Determinants (GOOD) study consists of 1068 men (18.9 ± 0.6 years of age). The TTTA repeat polymorphism (TTTAn) and three single nucleotide polymorphisms (SNPs), including the Val80 SNP, in the CYP19 gene, were analyzed. Serum levels of testosterone and estradiol were measured. Areal BMD (aBMD) was measured by DXA, whereas cortical and trabecular vBMD and cortical Bone Size were measured by pQCT. Results: The TTTAn and the Val80 genotypes were independent predictors of aBMD of the radius, lumbar spine, total body, and cortical Bone Size (cortical cross-sectional area and thickness) of both the radius and tibia. In contrast, trabecular vBMD was not associated with CYP19 polymorphisms. Homozygosity for the long allele (>9 repeats) of the TTTAn and for the G allele of the Val80 SNP was associated with the highest aBMD and testosterone levels as well as with the greatest cortical Bone Size. Regression analyses indicated that the association with aBMD was mediated through affected cortical Bone Size. Conclusions: We showed, in a large well-characterized cohort of men at the age of peak Bone mass, that several common aromatase polymorphisms are associated with cortical Bone Size but not with trabecular vBMD. One may speculate that affected CYP19 activity, resulting in altered testosterone levels during pubertal development, might contribute to the association between CYP19 polymorphisms and cortical Bone Size.
Ego Seeman - One of the best experts on this subject based on the ideXlab platform.
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fracture site specific deficits in Bone Size and volumetric density in men with spine or hip fractures
Journal of Bone and Mineral Research, 2001Co-Authors: Ego Seeman, Yunbo Duan, Christopher Fong, Jan EdmondsAbstract:To study the structural basis of Bone fragility in men, we compared Bone Size and volumetric Bone mineral density (vBMD) of the third lumbar vertebra and femoral neck in 95 men with spine fractures, 127 men with hip fractures, and 395 healthy controls using dual-energy X-ray absorptiometry (DXA). The results were expressed in absolute terms and age-specific SD scores (mean ± SEM). In controls, vertebral body and femoral neck width increased across age, being 0.46 ± 0.11 SD and 0.91 ± 0.08 SD higher in elderly men than in young men, respectively (both, p < 0.001). Men with spine fractures had reduced vertebral body width (−0.45 ± 0.10 SD; p < 0.01) but not femoral neck width (−0.15 ± 0.10 SD, NS). Men with hip fractures had reduced femoral neck width (−0.45 ± 0.11 SD; p < 0.01) and vertebral body width (−0.25 ± 0.10 SD; p < 0.05). The deficits in Bone volume (BV) exaggerated the deficits in Bone mineral content (BMC) by 40% at the vertebrae in men with spine fractures and by 9% at the femoral neck in men with hip fractures. vBMD deficits were greater at the vertebrae in men with spine fractures than in men with hip fractures (−1.37 ± 0.08 SD vs.−0.70 ± 0.10 SD, respectively; p < 0.01) but were similar at the femoral neck (−0.93 ± 0.10 SD and −0.76 ± 0.11 SD, respectively, NS), despite the men with spine fracture being 10 years younger. Bone fragility leading to spine or hip fractures in men may be the result of fracture site-specific deficits in Bone Size and vBMD that have their origins in growth, aging, or both.
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On exposure to anorexia nervosa, the temporal variation in axial and appendicular skeletal development predisposes to site-specific deficits in Bone Size and density: a cross-sectional study.
Journal of Bone and Mineral Research, 2000Co-Authors: Ego Seeman, Magnus K Karlsson, Yunbo DuanAbstract:Skeletal development is heterogeneous. Throughout growth, Bone Size is more maturationally advanced than the mineral being accrued within its periosteal envelope; before puberty, appendicular growth is more rapid than axial growth; during puberty, appendicular growth slows and axial growth accelerates. We studied women with differing age of onset of anorexia nervosa to determine whether this temporal heterogeneity in growth predisposed to the development of deficits in Bone Size and volumetric Bone mineral density (vBMD), which varied by site and severity depending on the age at which anorexia nervosa occurred. Bone Size and vBMD of the third lumbar vertebra and femoral neck were measured using dual-energy X-ray absorptiometry in 210 women aged 21 years (range, 12–40 years) with anorexia nervosa. Results were expressed as age-specific SDs (mean ± SEM). Bone width depended on the age of onset of anorexia nervosa; when the onset of anorexia nervosa occurred (1) before 15 years of age, deficits in vertebral body and femoral neck width did not differ (−0.77 ± 0.27 SD and −0.55 ± 0.17 SD, respectively); (2) between 15 and 19 years of age, deficits in vertebral body width (−0.95 ± 0.16 SD) were three times the deficits in femoral neck width (−0.28 ± 0.14 SD; p < 0.05 comparing the deficits), (3) after 19 years of age, deficits in the vertebral body width (−0.49 ± 0.26 SD; p = 0.05) were half that in women with earlier onset of anorexia nervosa. No deficit in Bone width was observed at the femoral neck. Deficits in vBMD at the vertebra and femoral neck were independent of the age of onset of anorexia nervosa but increased as the duration of anorexia nervosa increased, being about 0.5 SD lower at the vertebra than femoral neck. We infer that the maturational development of a region at the time of exposure to disease, and disease duration, determine the site, magnitude, and type of trait deficit in anorexia nervosa. Bone fragility due to reduced Bone Size and reduced vBMD in adulthood is partly established during growth.
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Bone Size and volumetric density in women with anorexia nervosa receiving estrogen replacement therapy and in women recovered from anorexia nervosa.
The Journal of Clinical Endocrinology and Metabolism, 2000Co-Authors: Magnus K Karlsson, Susan J. Weigall, Yunbo Duan, Ego SeemanAbstract:Anorexia nervosa is associated with Bone loss during adulthood, but may also delay skeletal growth and mineral accrual during growth. We asked the following questions. 1) Is anorexia nervosa associated with reduced Bone Size and reduced volumetric Bone mineral density (vBMD)? 2) Is estrogen replacement therapy (ERT) or recovery from anorexia nervosa associated with normal Bone Size and vBMD? Using dual-energy x-ray absorptiometry, we measured Bone Size and vBMD of the third lumbar vertebra and femoral neck in a cross-sectional study of 161 female patients: 77 with untreated anorexia nervosa, 58 with anorexia nervosa receiving ERT, 26 recovered from anorexia nervosa, and 205 healthy age-matched controls. Results were expressed as the sd or z-score (mean ± sem). Deficits in vertebral body and femoral neck width in untreated women were −1.0 ± 0.1 and −0.3 ± 0.1 sd (P < 0.001 and P < 0.05, respectively). Deficits in Bone width were less in the ERT-treated women than in untreated women at the vertebral body (−...
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the differing tempo of growth in Bone Size mass and density in girls is region specific
Journal of Clinical Investigation, 1999Co-Authors: Shona Bass, Pierre D Delmas, G Pearce, E Hendrich, Aaron Tabensky, Ego SeemanAbstract:: The differing tempo and direction of growth of the periosteal and endocortical surfaces, and the differing tempo of growth of the axial and appendicular skeleton, may predispose to regional deficits in Bone Size, Bone mineral content (BMC), and volumetric Bone mineral density (vBMD). These traits were measured during 2 years by dual x-ray absorptiometry in 109 girls. By 7 years of age, Bone Size was approximately 80% of its maturational peak, and BMC was approximately 40% of its peak. Before puberty, the legs grew more rapidly than the trunk. During puberty, the growth spurt was truncal. Between 7 and 17 years, femoral and lumbar spine BMC increased by 50-150% because Bone Size increased. vBMD increased by 10-30%. Thus, growth builds a bigger, but only moderately denser, skeleton. Regions growing rapidly, or distant from their peak, may be more severely affected by illness than those growing slowly or nearer completion of growth. Depending on the age of exposure to disease, deficits may occur in limb dimensions (prepuberty), spine dimensions (early puberty), or vBMD by interference with mineral accrual (late puberty). As vBMD is independent of age before puberty, the position of an individual's vBMD in the population distribution is established early in life. Bone fragility in old age may have its foundations in growth.
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Chapter 6 – Bone Size, Mass, and Volumetric Density: The Importance of Structure in Skeletal Health
Osteoporosis in Men, 1999Co-Authors: Ego SeemanAbstract:Publisher Summary Bone fragility in men in old age is the result of reduced Bone Size or architectural changes accompanying Bone loss such as cortical thinning, trabecular thinning, and loss of connectivity. Men have fewer spine fractures than women because their peak Bone Size is greater; greater vertebral width (not height) confers greater breaking strength. Although men have bigger Bones, the amount of Bone in the (bigger) Bone–the peak vertebral volumetric trabecular BMD (trabecular number and thickness)—is the same in men and women. Vertebral body fragility increases less in men than in women during aging because the loss of trabecular Bone proceeds primarily by thinning caused by reduced Bone formation, whereas increased remodeling in women caused by menopause contributes to trabecular thinning and loss of connectivity. Men may have fewer hip fractures than women, in part, because proximal femur Bone mass and Size is greater in men. Femur length and width is greater in men than women because prepubertal growth is two years longer, and pubertal growth velocity is more rapid and ceases later in males. Although femoral neck and shaft cortical thickness is the same in men and women, the cortex is placed farther from the neutral axis in men conferring greater bending strength. The higher proximal femoral BMC and areal BMD in men is the result of greater Bone Size; volumetric cortical BMD does not differ by gender.
Dan Mellström - One of the best experts on this subject based on the ideXlab platform.
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Exercise During Growth and Young Adulthood Is Independently Associated With Cortical Bone Size and Strength in Old Swedish Men
Journal of Bone and Mineral Research, 2014Co-Authors: Martin Nilsson, Magnus K Karlsson, Claes Ohlsson, Dan Mellström, Daniel Sundh, Mattias LorentzonAbstract:Previous studies have reported an association between exercise during youth and increased areal Bone mineral density at old age. The primary aim of this study was to investigate if exercise during growth was independently associated with greater cortical Bone Size and whole Bone strength in weight-bearing Bone in old men. The tibia and radius were measured using both peripheral quantitative computed tomography (pQCT) (XCT-2000; Stratec) at the diaphysis and high-resolution pQCT (HR-pQCT) (XtremeCT; Scanco) at the metaphysis to obtain cortical Bone geometry and finite element-derived Bone strength in distal tibia and radius, in 597 men, 79.9 +/- 3.4 (mean +/- SD) years old. A self-administered questionnaire was used to collect information about previous and current physical activity. In order to determine whether level of exercise during growth and young adulthood or level of current physical activity were independently associated with Bone parameters in both tibia and radius, analysis of covariance (ANCOVA) analyses were used. Adjusting for covariates and current physical activity, we found that men in the group with the highest level of exercise early in life (regular exercise at a competitive level) had higher tibial cortical cross-sectional area (CSA; 6.3%, p
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previous sport activity during childhood and adolescence is associated with increased cortical Bone Size in young adult men
Journal of Bone and Mineral Research, 2009Co-Authors: Martin Nilsson, Claes Ohlsson, Dan Mellström, Mattias LorentzonAbstract:Physical activity during growth has been associated with altered cortical Bone geometry, but it remains uncertain if the physical activity–induced increments in cortical Bone Size remain when the level of physical activity is diminished or ceased. The aim of this study was to investigate if physical activity during growth is associated with cortical Bone geometry in currently inactive young men. In this study, 1068 men (18.9 ± 0.6 [SD] yr) were included. Cortical Bone geometry at the tibia and radius were measured using pQCT. A standardized questionnaire was used to collect information about current and previous sport activity. Subjects who continued to be active (n = 678) and who had been previously active (n = 285) in sports had a wider cortical Bone (periosteal circumference [PC], 4.5% and 3.2%, respectively) with increased cross-sectional area (CSA; 12.5% and 6.9%) of the tibia than the always inactive subjects (n = 82). In the currently inactive men (n = 367), regression analysis (including covariates age, height, weight, calcium intake, smoking, and duration of inactivity) showed that previous sport activity was independently associated with cortical Bone Size of the tibia (CSA and PC). Amount of previous sport activity explained 7.3% of the total variation in cortical CSA. Subjects, who ceased their sport activity for up to 6.5 yr previously, still had greater cortical PC and CSA of the tibia than always inactive subjects. The results from this study indicate that sport activity during growth confers positive effects on Bone geometry even though sport activity is ceased.
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leptin is a negative independent predictor of areal bmd and cortical Bone Size in young adult swedish men
Journal of Bone and Mineral Research, 2006Co-Authors: Mattias Lorentzon, Dan Mellström, Kerstin Landin, Claes OhlssonAbstract:The association between leptin and areal BMD has been controversial, and the predictive role of leptin on cortical volumetric BMD and Bone Size has not previously been studied. We show that leptin is a negative independent predictor of aBMD (DXA), at several measured sites, and of cortical Bone Size (pQCT) in a large population of young men. Introduction: Recent findings suggest that both adipose tissue (AT) and Bone mass are regulated by leptin. Previous reports studying the association between leptin and areal BMD (aBMD) have yielded conflicting results. The role of leptin on volumetric BMD (vBMD) and Bone Size of the cortical and trabecular Bone compartments has not previously been studied. Materials and Methods: The Gothenburg Osteoporosis and Obesity Determinants (GOOD) study is a population-based study of 1068 men (age, 18.9 ± 0.6 [SD] years). aBMD of the total body, lumbar spine, femoral neck, both radii, and trochanter, as well as total body AT and lean mass (LM) were measured using DXA, whereas cortical and trabecular vBMD and Bone Size were measured by pQCT. Results: Total body LM could explain a larger magnitude of the difference in the variation in aBMD and cortical Bone Size than what total body AT could (total body aBMD: LM 37.4% versus AT 8.7%; tibia cross-sectional area [CSA]: LM 46.8% versus AT 5.6%). The independent role of leptin on Bone parameters was studied using a multiple linear regression model, including age, total body LM and AT, height, present physical activity, calcium intake, and smoking as covariates. Leptin was found to be a negative independent predictor of aBMD (total body: β =−0.08, p =0.01; lumbar spine: β =−0.13, p < 0.01; trochanter: β =−0.09, p =0.01), as well as of the cortical Bone Size (CSA and thickness) of both the radius (CSA: β =−0.12, p < 0.001) and tibia (CSA: β =−0.08, p < 0.01), but not of the cortical or trabecular vBMD of these Bones. Conclusion: Our results indicate that LM has a greater impact on Bone mass than AT. Our findings further show that leptin is a negative independent predictor of aBMD at several measured sites and of Bone parameters reflecting cortical Bone Size, but not vBMD, in a large population of young Swedish men.
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Polymorphisms in the aromatase gene predict areal BMD as a result of affected cortical Bone Size: the GOOD study.
Journal of Bone and Mineral Research, 2005Co-Authors: Mattias Lorentzon, Charlotte Swanson, Anna-lena Eriksson, Dan Mellström, Claes OhlssonAbstract:The association between aromatase gene polymorphisms, Bone parameters, and sex steroid levels was studied in 1068 men (18.9 ± 0.6 years of age). Several aromatase gene polymorphisms were found to be associated with serum testosterone levels and cortical Bone Size but not with trabecular volumetric BMD. Introduction: Both testosterone and estrogens are important for the male skeleton. Aromatase, the product of the CYP19 gene, is the key enzyme in the conversion of testosterone to estradiol. A functional aromatase enzyme has been shown to be crucial for the normal development of the male skeleton. The role of genetic polymorphisms in the aromatase gene for trabecular volumetric BMD (vBMD) and cortical Bone Size has not previously been studied in men. Materials and Methods: The Gothenburg Osteoporosis and Obesity Determinants (GOOD) study consists of 1068 men (18.9 ± 0.6 years of age). The TTTA repeat polymorphism (TTTAn) and three single nucleotide polymorphisms (SNPs), including the Val80 SNP, in the CYP19 gene, were analyzed. Serum levels of testosterone and estradiol were measured. Areal BMD (aBMD) was measured by DXA, whereas cortical and trabecular vBMD and cortical Bone Size were measured by pQCT. Results: The TTTAn and the Val80 genotypes were independent predictors of aBMD of the radius, lumbar spine, total body, and cortical Bone Size (cortical cross-sectional area and thickness) of both the radius and tibia. In contrast, trabecular vBMD was not associated with CYP19 polymorphisms. Homozygosity for the long allele (>9 repeats) of the TTTAn and for the G allele of the Val80 SNP was associated with the highest aBMD and testosterone levels as well as with the greatest cortical Bone Size. Regression analyses indicated that the association with aBMD was mediated through affected cortical Bone Size. Conclusions: We showed, in a large well-characterized cohort of men at the age of peak Bone mass, that several common aromatase polymorphisms are associated with cortical Bone Size but not with trabecular vBMD. One may speculate that affected CYP19 activity, resulting in altered testosterone levels during pubertal development, might contribute to the association between CYP19 polymorphisms and cortical Bone Size.
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association of amount of physical activity with cortical Bone Size and trabecular volumetric bmd in young adult men the good study
Journal of Bone and Mineral Research, 2005Co-Authors: Mattias Lorentzon, Dan Mellström, Claes OhlssonAbstract:In this population-based study, amount of PA was associated with cortical Bone Size (increased thickness and periosteal circumference) and trabecular vBMD, but not with cortical vBMD or length of the long Bones in young men. The lowest effective amount of PA was ≥4 h/week. Introduction: Physical activity (PA) is believed to have positive effects on the skeleton and possibly help in preventing the occurrence of osteoporosis. Neither the lowest effective amount of PA needed to induce an osteogenic response nor its effect on the BMD and Size of the different Bone compartments (i.e., trabecular and cortical Bone) has yet been clarified. Materials and Methods: In this population-based study, we investigated the amount of all types of PA in relation to areal BMD (aBMD), trabecular and cortical volumetric BMD (vBMD), and cortical Bone Size in 1068 men (age, 18.9 ± 0.02 years), included in the Gothenburg Osteoporosis and Obesity Determinants (GOOD) study. aBMD was measured by DXA, whereas cortical and trabecular vBMD and Bone Size were measured by pQCT. Results and Conclusions: The amount of PA was associated with aBMD of the total body, radius, femoral neck, and lumbar spine, as well as with cortical Bone Size (increased thickness and periosteal circumference) and trabecular vBMD, but not with cortical vBMD or length of the long Bones. The lowest effective amount of PA was ≥4 h/week. aBMD, cortical Bone Size, and trabecular vBMD were higher in subjects who started their training before age 13 than in subjects who started their training later in life. Our data indicate that ≥4 h/week of PA is required to increase Bone mass in young men and that exercise before and during the pubertal growth is of importance. These findings suggest that PA is imperative for the augmentation of cortical Bone Size and trabecular vBMD but does not affect the cortical vBMD in young men.
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Clinical Investigations Do Young New Zealand Pacific Island and European Children Differ in Bone Size or Bone Mineral
2020Co-Authors: A. M. Grant, A. GouldingAbstract:Although Pacific Island adults have been shown to have larger Bones and greater Bone mineral density than caucasians, no previous studies have been undertaken to determine whether differences are present in prepubertal children. Forty-one Pacific Island chil- dren (both parents of Pacific Island descent) and 38 European children, aged 3 to 7 years, living in New Zealand were studied. Heights and weights were deter- mined by simple anthropometry and body mass index (BMI, kg/m 2 ) was calculated. Body composition, Bone Size, and Bone mineral content (BMC, g) were measured by dual energy X-ray absorptiometry (DXA) of the total body and the non-dominant forearm. Compared to European children, in data adjusted for age and gender, Pacific Island children had significantly greater (P < 0.05) BMC in the total body (12%), the ultradistal ra- dius (16%), and the 33% radius (8%), and also greater total body Bone area (10%). Bone mineral density (BMD, g/cm 2 ) was higher only at the ultradistal radius (11%). However, after adjustment for body weight, in particular lean mass, no differences were seen between Pacific Island and European children in any Bone mea- sure. The larger Bone area and BMC of young Pacific Island children can be explained by their greater height and weight. Therefore, this study has shown that pre- pubertal Pacific Island children do not have greater Bone Size or BMC for their weight.
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Do Young New Zealand Pacific Island and European Children Differ in Bone Size or Bone Mineral?
Calcified Tissue International, 2005Co-Authors: A. M. Grant, F. K. Gordon, E. L. Ferguson, S.m. Williams, T. E. Henry, V. M. Toafa, B.e. Guthrie, A. GouldingAbstract:Although Pacific Island adults have been shown to have larger Bones and greater Bone mineral density than caucasians, no previous studies have been undertaken to determine whether differences are present in prepubertal children. Forty-one Pacific Island children (both parents of Pacific Island descent) and 38 European children, aged 3 to 7 years, living in New Zealand were studied. Heights and weights were determined by simple anthropometry and body mass index (BMI, kg/m^2) was calculated. Body composition, Bone Size, and Bone mineral content (BMC, g) were measured by dual energy X-ray absorptiometry (DXA) of the total body and the non-dominant forearm. Compared to European children, in data adjusted for age and gender, Pacific Island children had significantly greater ( P < 0.05) BMC in the total body (12%), the ultradistal radius (16%), and the 33% radius (8%), and also greater total body Bone area (10%). Bone mineral density (BMD, g/cm^2) was higher only at the ultradistal radius (11%). However, after adjustment for body weight, in particular lean mass, no differences were seen between Pacific Island and European children in any Bone measure. The larger Bone area and BMC of young Pacific Island children can be explained by their greater height and weight. Therefore, this study has shown that prepubertal Pacific Island children do not have greater Bone Size or BMC for their weight.
