Bone Mineral Content Of Radius Research Articles

Bone Mineral and Predictors of Bone Mass in White, Hispanic, and Asian Early Pubertal Girls

Differences in bone among racial/ethnic groups may be explained by differences in body size and shape. Previous studies have not completely explained differences among white, Asian, and Hispanic groups during growth. To determine racial/ethnic differences and predictors of bone mass in early pubertal girls, we measured bone mineral content (BMC) in white, Hispanic, and Asian sixth-grade girls across six states in the United States. We developed models for predicting BMC for the total-body, distal radius, total-hip, and lumbar spine for 748 subjects. For each of the bone sites, the corresponding area from dual-energy X-ray absorptiometry (DXA) was a strong predictor of BMC, with correlations ranging 0.78-0.98, confirming that larger subjects have more BMC. Anthropometric measures of bone area were nearly as effective as bone area from DXA at predicting BMC. For total-body, distal radius, lumbar spine, and total-hip BMC, racial/ethnic differences were explained by differences in bone area, sexual maturity, physical activity, and dairy calcium intake. Bone size explained most of the racial/ethnic differences in BMC, although behavioral indicators were also significant predictors of BMC.

A two‐year prospective controlled study of bone mass and bone turnover in children with early juvenile idiopathic arthritis

To explore early changes and predictors of bone mass in children with juvenile idiopathic arthritis (JIA) in order to identify patients who will develop bone mass reductions. We conducted a prospective cohort study of 108 children with early JIA (ages 6-18 years; mean disease duration 19.3 months) who were individually matched with 108 healthy children for age, sex, race, and county of residence. Bone mass and changes in total body, spine, femur, and forearm bone mineral density and bone mineral content (BMC), body composition, growth, and biochemical parameters of bone turnover were examined at baseline and at followup a mean of 24 months later. Low bone mass was defined as a Z score >1 SD below the reference population. Of the 200 children evaluated at followup, the 100 healthy children had greater gains in total body BMC (P = 0.035), distal radius BMC (P < 0.001), and total body lean mass (P < 0.001) than did the 100 JIA patients. Low or very low total body BMC was observed in 24% of the patients and 12% of the healthy children. Bone formation, bone resorption, and weight-bearing activities were reduced in the patients compared with the healthy children. Multiple regression analysis showed that in patients with JIA, serum bone-specific alkaline phosphatase, serum C-telopeptide of type I collagen, and weight-bearing activities were independent predictors of changes in total body BMC. Total body BMC was lower in patients with polyarticular onset than in those with oligoarticular disease onset. Patients with JIA have moderate reductions in bone mass gains, bone turnover, and total body lean mass early in the disease course.

Sex differences in the effect of body-composition variables on bone mass in healthy children and adolescents

Prophylactic interventions against osteoporosis require a determination of the factors that influence the accumulation of bone mass during growth. The objective was to determine the independent sex-specific contribution of lean mass and fat mass to bone mineral content (BMC), after adjustment for anthropometric variables and lifestyle factors, in healthy children and adolescents. Healthy schoolchildren (184 boys and 179 girls) aged 10-17 y (x+/- SD: 13.0 +/- 2.1 y) participated in this cross-sectional study. Total and regional (lumbar spine, femoral neck, and distal one-third of the radius) BMC and body composition were measured by dual-energy X-ray absorptiometry. A significant effect of anthropometric variables and lifestyle factors on BMC was observed at all skeletal sites. Lean mass and fat mass showed robust correlations with BMC, even after adjustment for anthropometric variables and lifestyle factors. Lean mass contributed to 6-12% of the variance in BMC in boys and to 4-10% in girls. Fat mass accounted for 0.1-2% of BMC variance in boys and to 0.1-6.5% in girls. Both lean mass and fat mass are consistent predictors of BMC at multiple skeletal sites in healthy children and adolescents. The contribution of lean mass to BMC variance was larger in boys than in girls. In both sexes, the highest contribution of lean mass to BMC was observed at the femoral neck.

Relative contributions of bone density, bone turnover, and clinical risk factors to long-term fracture prediction.

Long-term fracture prediction using bone mineral density remains controversial, as does the additional contribution from assessing bone turnover or clinical risk factors. We measured bone mineral density at various sites, along with biochemical markers of bone turnover, sex steroid levels, and over 100 clinical variables, at baseline on an age-stratified sample of 304 Rochester, MN women in 1980. The 225 postmenopausal women were subsequently followed for 3146 person-years (median, 16.2 years per subject), wherein they experienced 302 new fractures: 81% resulted from minimal or moderate trauma and 60% of these involved the proximal femur, thoracic or lumbar vertebrae, or distal forearm. Accounting for multiple fractures per subject, these osteoporotic fractures together were best predicted by baseline femoral neck bone mineral density (age-adjusted hazard ratio [HR] per SD decrease, 1.37; 95% CI, 1.10-1.70); 19 moderate trauma forearm fractures were best predicted by distal radius bone mineral content, whereas 28 hip fractures and 100 vertebral fractures were best predicted by femoral neck bone mineral density. Femoral neck bone mineral density performed comparably in predicting osteoporotic fracture risk within the first decade of follow-up (HR, 1.38; 95% CI, 1.10-1.74) as well as more than 10 years after baseline (HR, 1.39; 95% CI, 1.05-1.84). The older biochemical markers were not associated with fractures, but serum "free" estradiol index was independently predictive of short- and long-term fracture risk. Consistent clinical risk factors were not identified, but statistical power was limited. Identifying patients at increased long-term risk of fracture is challenging, but it is reassuring that femoral neck bone mineral density can predict osteoporotic fractures up to 20 years later.

Dietary calcium, protein, and phosphorus are related to bone mineral density and content in young women

Dietary factors have been implicated in modifying bone health, although the results remain controversial, particularly in young women. The objective of the study was to determine relations of selected dietary factors and anthropometric measurements to bone mineral density (BMD) of the spine, femoral neck, trochanter, Ward's triangle, radius, and total body and the bone mineral content (BMC) of the spine, radius, and total body. The study was a cross-sectional analysis of 215 women aged 18-31 y. Weight, height, and lean mass were correlated with bone mineral measures at every site (r = 0.17-0.78). Postmenarcheal age (years since onset of menses) was positively correlated with total-body BMD and BMC, radius BMD and BMC, and spine BMC, and negatively correlated with Ward's triangle BMD. Radius BMD was correlated with protein, calcium, and phosphorus intakes, and spine BMD and BMC were correlated with energy, protein, calcium, and phosphorus intakes. These correlations remained significant when postmenarcheal age, lean mass, and fat mass were controlled. A pattern emerged in multiple regression analyses that showed a complex relation among calcium, protein or phosphorus, and the calcium-protein or calcium-phosphorus ratio and spine or total-body BMC and BMD. All 3 variables (calcium, protein or phosphorus, and calcium-protein or calcium-phosphorus ratio) were required in the model for significance. Anthropometric measures were predictors of bone mass. A single ratio of calcium to phosphorus or protein did not optimize bone mass across the range of calcium intakes.

Relation of Nutrition, Body Composition and Physical Activity to Skeletal Development: A Cross-Sectional Study in Preadolescent Females

Objective: To examine the relation of anthropometric and growth parameters (weight, stature, body composition, age, and skeletal age), nutritional factors, and physical activity to the total body and radius bone mineral density and content and radiogrammetry parameters of the second metacarpal.Study design: The study was a cross-sectional evaluation of 456 healthy, Caucasian girls, ages 8 to 13 years. Multiple regression models were created based on Cp statistics to determine the association between bone parameters and various independent variables.Results: Mean calcium intake was 956±381 mg/day, about 20% below the RDA of 1200 mg/day and about 36% below the threshold intake of approximately 1500 mg/day. The most significant predictors for total body and radius bone mineral density were corresponding bone areas, lean body mass, body fat, skeletal age, dietary calcium, and stature (only for total body) with corresponding R2(adjusted) of 48% and 36%. The total body and radius bone mineral content was positively associated with corresponding bone areas, lean body mass, body fat, calcium intake, and skeletal age with corresponding R2(adjusted) of 86% and 72%. Energy expenditure (corrected for BMI) was stratified into quartiles and bone mass parameters were distributed accordingly. A statistically significant difference in total body and radius bone mineral density and content was noted between the fourth and lower quartiles (ANOVA, p<0.05 to p<0.0001).Conclusion: The most significant predictors of bone mass in preadolescent females evaluated in this study are bone area, lean body mass, body fat, skeletal age and dietary calcium.

Increased biochemical markers of bone formation and resorption in primary hyperparathyroidism with special reference to patients with mild disease.

To evaluate the impact on bone turnover of primary hyperparathyroidism (pHPT) with special reference to patients with mild pHPT, using biochemical markers of bone formation and resorption. A longitudinal study of patients with pHPT before and one year after surgical treatment. The Departments of Internal Medicine and Surgery, Lund University Hospital. Forty consecutive patients with pHPT. Thirty of these patients had mild pHPT and are reported separately. Data on bone mineral was also compared to a reference population. All patients were operated upon and restudied one year later. Bone resorption and formation was studied by means of the serum concentrations of the telopeptide of the carboxyterminal region of type 1 collagen (ICTP) and of alkaline phosphatase (ALP), osteocalcin and the carboxyterminal propeptide of type 1 procollagen (PICP), respectively. Bone density was measured at the distal radius by single photon absorptiometry (SPA). Bone formation markers consistently decreased after parathyroid surgery: ALP from 3.51 +/- 0.23 to 2.94 +/- 0.21 microkat L(-1) (P < 0.05), osteocalcin from 6.15 +/- 0.53 to 2.89 +/- 0.23 microg L(-1) (P < 0.001) and PICP from 126.4 +/- 10.9 to 96.0 +/- 6.5 microg L(-1) (P < 0.001). In parallel, the ICTP concentration, reflecting bone resorption, decreased from 5.10 +/- 0.54 to 3.94 +/- 0.34 microg L(-1) (P < 0.001). There was not any significant change in distal radius bone mineral 1 one year after surgery. In the subgroup of patients classified as mild pHPT, a significant decrease was noted for osteocalcin, PICP and for ICTP but not for ALP, without significant changes in variables reflecting distal radius bone mineral content. Glomerular filtration rate was inversely correlated to serum levels of intact PTH, ionized calcium, alkaline phosphatase, osteocalcin and ICTP and directly correlated to the 1.25-dihydroxy-vitamin D concentrations. pHPT is associated with substantial changes in circulating levels of biochemical markers of bone formation and resorption. These findings are also present in patients with mild pHPT. Renal function should be considered in the evaluation of the impact of pHPT on bone turnover.

Serum interleukin-6 and bone metabolism in patients with thyroid function disorders.

To determine the possible involvement of interleukin-6 (IL-6) in the bone loss of hyperthyroidism, relationships between thyroid status, biochemical and densitometric parameters of bone metabolism, and IL-6 were studied in female subjects. Patients with hyperthyroidism caused by either toxic nodular goiter or Graves' disease had significantly higher serum IL-6 concentrations than normal controls. Within the control group, serum IL-6 was higher in postmenopausal than in premenopausal women, but this influence of menopausal status was not seen in the hyperthyroid patients. The production of IL-6 by blood mononuclear cells was higher in cells from the hyperthyroid women. Bone turnover was increased in the hyperthyroid patients based on serum osteocalcin and urinary deoxypyridinoline excretion, and the hyperthyroid group also had reduced radius bone mineral content (BMC). A subgroup of hyperthyroid patients who had the lowest BMC (values more than 1 SD below normal age-matched controls) also had serum IL-6 concentrations significantly greater than those of hyperthyroid patients showing less reduction of BMC. The correlations observed in this study support the possibility that IL-6 plays a role in mediating the bone loss that results from excess thyroid hormone.

Previous physical activity relates to bone mineral measures in young women.

Exercise may increase accretion of bone, potentially reducing the risk of osteoporosis. Previous physical activity was assessed in 204 minimally active young women (18-31 yr). Bone mineral content (BMC) and bone mineral density (BMD) for the total body, femoral neck, and spine were assessed by a dual x-ray absorptiometer, and the radius by a single photon absorptiometer. Self-reported occupation and leisure activity for the 5 yr before enrollment in the study, as well as high school and college sports participation, were assigned energy expenditure (EE) values. From this information, EE variables were created as follows: 1) occupation EE + leisure EE + high school sport and/or college sport EE if within prior 5 yr (5-yr EE); 2) occupation EE + leisure EE (occupation + leisure EE); and 3) high school sport EE (high school EE). These variables were correlated with bone mineral measures and significant results follow (P < 0.05). Five-year EE and occupation + leisure EE correlated with all measures of bone health (r from 0.13 to 0.39). High school EE correlated with total body BMD (r = 0.25) and BMC (r = 0.28), femoral neck BMD (r = 0.28), radius BMC (r = 0.20), as well as spine BMD (r = 0.20) and BMC (r = 0.27). When weight was controlled, 5-yr EE and occupation + leisure EE remained correlated with all BMC measures (r from 0.14 to 0.22). When controlled for weight, high school EE remained associated with femoral neck BMD (r = 0.24), total body BMD (r = 0.20) and BMC (r = 0.26), and spine BMC (r = 0.17). To partially control for selection bias, data were also controlled for total body BMD. Five-year EE and occupation + leisure EE remained positively correlated with all measures of BMC. High school EE remained correlated both with femoral neck BMD and total body BMC. In multiple regression analyses, 5-yr EE or occupation + leisure EE were significant predictors of all measures of bone health, except femoral neck BMD. High school EE was a significant predictor for total body BMD and BMC, femoral neck BMD, and spine BMC.

Postnatal attainment of intrauterine macromineral accretion rates in low birth weight infants fed fortified human milk

Hypothesis: Provision of more bioavailable mineral sources as human milk supplements enables very low birth weight (VLBW) infants to meet the intrauterine accretion rate for calcium and phosphorus. Design: Comparison of currently formulated human milk fortifier with previous formulation. Setting: Neonatal level II and III nurseries Patients: Twenty-six healthy, VLBW infants, whose mothers chose to breast-feed. Interventions: We tested the effects of two formulations designed for VLBW infants as human milk supplements and differing primarily in their quantity and source of Ca, P, and magnesium. The study interval began with a milk intake of 100 ml · kg -1 · day -1 and ended when a body weight reached 2.0 kg. Main outcome measures: Net absorption and retention of Ca, P, and Mg during a nutritional balance study conducted once during the study interval, growth during the entire study interval, and bone mineral content of the radius were measured at the beginning and end of the study interval. Results: The newer Ca gluconate-glycerophosphate preparation (given to group CaGP) resulted in greater net absorption and retention of Ca and P ( p <0.01) than in infants given Ca phosphate (group CaTB). Mg retention was greater than (in group CaGP) or equivalent to (in group CaTB) the intrauterine accretion rate. Radius bone mineral content was significantly greater in group CaGP than in group CaTB ( p <0.001). Volumes of the fortified human milk preparation needed to meet the needs for gain in body weight were higher in group CaGP than in group CaTB ( p <0.001). Conclusions: Intrauterine accretion rates for Ca and P can be achieved when VLBW infants are fed human milk supplemented with Ca gluconate-glycerophosphate. Supplementation of human milk with Mg may not be indicated. In this study, greater intakes of Ca and P, and not improvements in bioavailability, result in improved net retention and bone mineral content of VLBW infants. (J P ediatr 1995;126:441-7)

A one-year prospective comparison of calcium supplementation, low dose continuous, and moderate dose cyclical oestrogen and progestagen replacement therapy in the protection of bone mass

SummaryAfter 6 months of calcium supplementation, 86 recently postmenopausal women chose either to remain on calcium or to add hormone replacement therapy. Women who chose hormones were allocated at random to either a low dose continuous (conjugated oestrogens, 0-3 mg/ day and medroxyprogesterone, 2-5 mg/day) or a moderate dose cyclical (conjugated oestrogens, 0-625 mg/ day, and medroxyprogesterone, 5 mg/day) regimen. Lumbar spine bone mineral density and mass, mid radius bone mineral content, and whole body bone turnover were measured.Menopause symptoms were controlled by both hormone regimens, and both produced decreases in whole body bone turnover and increases in lumbar spine density and mass over 1 year. On calcium only, lumbar spine bone mass continued to fall. Hormone replacement also prevented an age related decrease in the serum concentration of high density lipoproteins. More than 70 per cent of the subjects on moderate dose cyclical hormones experienced bleeding problems. With low dose continuo...

Bone Density and Bone Mineral Content of Adolescent Soccer Athletes and Competitive Swimmers

This cross-sectional study compared differences in os calcis bone density and distal radius bone mineral content (BMC) among adolescent soccer players, competitive swimmers, and control subjects. Sixty-eight males and females (23 soccer players, 20 swimmers, 25 controls) ages 13 to 17 served as subjects. The results for os calcis trabecular density indicate a trend that may be of clinical significance and that may warrant further study. The swimmers had the lowest os calcis density in both sexes whereas the soccer players had the highest bone density at this weight-bearing site (F=2.54, p&lt;.08). No differences with respect to distal radius BMC were observed among activity groups or between sexes.

Involvement of low-calcium diet in the reduced bone mineral content of idiopathic renal stone formers

The possibility that low-calcium intake in renal stone formers could lead to reduced bone mineral content was investigated in 123 male patients with idiopathic urolithiasis. Radius bone mineral content (BMC) was measured by single photon absorptiometry. Two groups of patients were analyzed: group 1 (n = 63) maintained on a free diet; group 2 (n = 60) maintained on a low-calcium diet (350 mg/day +/- 20 SEM) for 3.9 years +/- 0.6 SEM. The two groups of patients were investigated after a standard reduction of calcium intake for at least 1 week. The urinary excretion of calcium and of hydroxyproline, and the serum alkaline phosphatase activity were higher in both groups than in normal subjects submitted to the same low-calcium diet. Both groups of stone formers showed lowered radius BMC values at 3 cm (distal) and 8 cm (proximal) above the styloid process, but distal BMC was significantly lower in group 2 than in group 1. The results suggest that low-calcium intake could worsen the already decreased BMC of idiopathic renal stone formers.

Deterring bone loss by exercise intervention in premenopausal and postmenopausal women

This study investigated the efficacy of 4 years of exercise intervention in deterring bone loss in middle-aged women, and is a correction and extension of previously published data. Sixty-two control subjects (mean age 50.8) and 80 exercise subjects (mean age 50.1) completed a 4-year study. Subjects exercised three times a week, 45 minutes per session. Bilateral radius, ulna, and humerus bone mineral content (BMC) and width (W) were measured on each subject 11 times over the 4-year period. The two groups did not differ initially in age, height, or weight, but the control group had a greater maximum VO2 (ml/kg/min) than the exercise group. Slopes and intercepts of the bone variables vs. time were determined for each subject, and these values were used for between-group comparisons of loss. The control group BMC and BMC/W declined significantly in all three bones in both arms. The exercise group rate of decline was significantly less than that of the control group for 12 of the 18 bone variables. The greatest effect of the exercise intervention was on the ulna and radius. Exercise subjects lost significantly less than control subjects in left and right ulna and radius BMC and BMC/W, and left ulna and radius W. Lesser differences between groups were observed in the humerus. BMC and W loss rates of the left humerus were reduced in the exercise group, with no difference between exercise and control subjects in the other humerus variables. To determine if menopausal status influenced the response to exercise, we analyzed the difference between groups for premenopausal and postmenopausal subjects separately. Regardless of menopausal status, exercise subjects had lower bone loss rates than control subjects. In both premenopausal and postmenopausal subjects, exercise reduced bone loss significantly for 10 of the 18 bone variables. It can be concluded that physical activity significantly reduces bone loss in the arms of middle-aged women.

Relationships between usual nutrient intake and bone-mineral content of women 35–65 years of age: longitudinal and cross-sectional analysis

In a 4-yr clinical trial, effect on single-photon absorptiometric measurements of arm bones of usual intakes of energy and 14 nutrients plus vitamin-mineral supplements was studied in 99 women, aged 35–65, randomly assigned to placebo (NS) or calcium-supplemented (1.5 g) (S) groups. Cross-sectional analysis of intial bone measurements showed vitamin C (r = 0.313, p < 0.05) and niacin (r = 0.353, p < 0.01) correlated with ulna in postmenopausal subjects (n = 67). Longitudinal analysis of bone-change rates of postmenopausal subjects (NS + S) showed higher calcium intakes associated with lower loss rates of humerus bone-mineral content (BMC) (r = 0.360, p < 0.01). In postmenopausal NS but not S subjects, energy, protein, calcium, phosphorus, zinc, and folate correlated significantly with change in radius BMC; high levels of intake correlated with slower loss (p < 0.05). Several nutrients besides calcium are related to bone loss in women.

Total body bone mineral and lean body mass by dual-photon absorptiometry

Dual-photon absorptiometry using 153Gd (44 and 100 keV) was used to measure the bone mineral content (BMC) of the trunk and of the total body (TBBM) in 7 volunteers with no overt bone disease. These values were compared to those obtained with partial-body neutron activation of calcium (trunk Ca). The trunk Ca seemed to represent best a 60 x 30 cm area; the correlation coefficient with the corresponding BMC in that area was 0.97 (SEE congruent to 7%). Trunk Ca was also highly correlated with TBBM (r = 0.96; SEE = 8%) and with radius BMC (r = 0.92; SEE = 11%), but the correlations with the BMC of smaller subareas of the trunk were lower (r congruent to 0.9; SEE approximately 12%). The BMC of the lumbar spine was only moderately correlated with trunk Ca, radius BMC and TBBM (r approximately 0.82; SEE approximately 18%), and only slightly more associated with trunk BMC (r approximately 0.88; SEE approximately 14%). The BMC of the combined lumbar-thoracic spine showed higher correlations with trunk Ca, radius BMC and TBBM (r approximately 0.87; SEE approximately 13%), and trunk BMC (r = 0.93; SEE approximately 10%). An accurate and sensitive measure of spinal status requires a direct measurement of that area.

IN VIVO BONE MINERAL CONTENT IN SICKLE CELL ANEMIA

Bone Mineral Content (BMC) was determined by the photon absorption method of Cameron and Sorenson in 58 black children (33 females and 25 males) with confirmed sickle cell anemia (SS). Bone scans were performed through the mid-radius (cortical bone) using 125-iodine as a monochromatic source of photons. Data is expressed both as GM/cm scanned or as the ratio of BMC to bone width (BMC/BW). The values obtained in these patients were compared to values in normal black and white children. BMC in normal black and white children showed what appeared to be a linear increase with age. In accordance with the data of Trotter, et al, we found that radius BMC is higher in black than in white at all ages, although accuracy and precision are less below the age of two. 64%. of males and 39% of females with sickle cell disease have less BMC than normal black children of the same age (less than 95% confidence limits). The ratio BMC/BW as related to age follows the normal pattern indicating similar reduction in BMC and BW in affected children. The factors contributing to the sex difference as regards the mineralization are not clear. Severity of anemia and transfusion need are considered as possible factors determining the extent of mineral loss.