Forearm Bone Density Research Articles

Measuring forearm bone density instead of lumbar spine bone density improves the sensitivity of diagnosing osteoporosis in older adults with cardiovascular diseases: Data from SARCOS study

IntroductionIn older individuals with cardiovascular diseases, it has been challenging to diagnose osteoporosis due to aortic calcification and degenerative processes in the spine of older adults, especially in very old adults. AimTo assess whether the distal forearm BMD with the proximal femur BMD has greater sensitivity for the diagnosis of osteoporosis than the lumbar spine BMD with the proximal femur BMD. MethodsWe evaluated 515 older adults with cardiovascular disease from the SARCOS study and stratified them into under and over 80-year-old age groups and according to gender. Two diagnostic criteria were used to assess osteoporosis, SPF (lumbar spine and proximal femur BMD) and DFF (distal forearm and proximal femur BMD), which were compared with the multiple bone sites (MS) criteria (lumbar spine, distal radius, femoral neck, and total femur BMD). Results43.9% were aged ≥80 years. Osteoporosis by SPF was diagnosed in 34% (n = 175), by DFF in 42.2% (n = 216), and by MS in 46.8% (n = 241). The characteristics of the three groups were similar. For every 100 older individuals with osteoporosis based on MS, 27 were not diagnosed by the SPF, and nine were not diagnosed by DFF (p = 0.001). The SPF did not diagnose osteoporosis in 23/100 in older adults aged <80 years, while DFF did not diagnose 16/100 (p.ns). In adults aged ≥80 years, the SPF did not identify osteoporosis in 31/100 older adults, while the DFF failed to identify it in only 5/100 (p < 0.001). In men and women aged ≥80 years, DFF showed higher sensitivity for the diagnosis of osteoporosis compared to the SPF criterion. ConclusionIn the elderly population with cardiovascular disease evaluated in our study, the use of distal forearm BMD instead of lumbar spine BMD, associated with proximal femur BMD, showed higher sensitivity for the diagnosis of osteoporosis, regardless of gender, and especially among the very older adults.

Arachidonic acid status negatively associates with forearm bone outcomes and glucose homeostasis in children with an overweight condition or obesity.

Long-chain polyunsaturated fatty acids are implicated in musculoskeletal health in adults. This study examined whether fatty acid status relates to bone health outcomes in children with overweight condition or obesity (body mass index z score, 3.1 ± 0.1; age, 9.0 ± 0.2 years; n = 108). Nondominant forearm bone density (distal one-third), geometry (4% site), and soft tissue composition (66%) were assessed using dual-energy X-ray absorptiometry and peripheral quantitative computed tomography. Red blood cell (RBC) fatty acid profile and indices of glucose homeostasis were measured. Differences in outcomes among RBC arachidonic acid (AA, C20:4n-6) tertiles were tested using mixed-model ANOVA. Ultra-, mid-, and total-distal forearm bone mineral content, adjusted for sex, age, percentage body fat, race, and forearm length, were 10% to 13% greater in children in the first AA tertile relative to the third. Children in the second tertile had the highest bone cross-sectional area and estimated strength at the 66% radius. Muscle cross-sectional area was 15% lower in the third tertile compared with the first, along with higher fasting insulin concentrations (27%) and homeostasis model of assessment estimate of insulin resistance (31%). Higher RBC AA status aligns with deficits in forearm bone mass, geometry, and muscle mass in children with excess adiposity and early signs of insulin resistance. Novelty Higher arachidonic acid status is associated with lower forearm bone mass in children with overweight condition or obesity. Children with higher arachidonic acid status had increased fasting insulin concentrations and indices of insulin resistance.

Measurement of Forearm Bone Density by Dual Energy X-Ray Absorptiometry Increases the Prevalence of Osteoporosis in Men With Celiac Disease

Guidelines advise measurement of bone mineral density (BMD) in patients with a diagnosis of celiac disease. The lumbar spine (LS) and hip sites are usually measured. Although skeletal sites rich in trabecular bone are believed to be vulnerable to osteoporosis in patients with celiac disease, most studies have not measured the cortical distal 1/3-radius. We collected data from 721 patients (mean age, 43.6 years; 68.4% female) with celiac disease who underwent 3-site dual energy x-ray absorptiometry (DXA, at a median 1.22 years after diagnosis). We assessed skeletal site- and sex-specific osteoporosis prevalence and the incremental utility of 1/3-radius measurement by DXA. Mean T- and Z-scores were normal in patients, but 43.3% had osteopenia and 19.6% had osteoporosis. Osteoporosis was found in 12.1% of patients at the LS, 5.3% of patients at the total hip, 7.6% of patients at the femoral neck, and 11.5% of patients at the 1/3-radius. A greater degree of villous atrophy at diagnosis was associated with male sex and lower T-scores at the 1/3-radius (P = .03), but not other skeletal sites. Isolated forearm osteoporosis was detected in 4.9% of patients. A higher proportion of patients with isolated forearm osteoporosis were male and had a greater weight and body mass index (all P < .01, compared to patients with osteoporosis only at other sites). Z-scores were lower at the LS and 1/3-radius and osteoporosis was more common in men than women. In men, the 1/3-radius was the most frequent site for osteoporosis. Among patients 50 years or older, isolated forearm osteoporosis was present in 10.7%. Based on DXA analysis of patients with celiac disease, the prevalence of osteoporosis appears to be underestimated-particularly in men when BMD at the 1/3-radius is not measured. Degree of villous atrophy is associated with BMD at the 1/3-radius and nearly 5% of patients have osteoporosis limited to that site. Recommendations for osteoporosis screening in patients with celiac disease should include measurement of the distal 1/3-radius in addition to the hip and LS.

Forearm bone density is not elevated in Inuit women with impaired fasting glucose or type 2 diabetes mellitus

ABSTRACT Bone mineral density (BMD) and fracture risk are elevated in adults with impaired fasting glucose (IFG) or type 2 diabetes mellitus (T2D). This study aimed to compare bone health among Inuit women with IFG, T2D and normoglycemia. The study included Inuit women (≥40 y) with IFG (n = 57), T2D (n = 72) or normoglycemia (n = 340) from the International Polar Year Inuit Health Survey 2007–2008 in Canada. Distal one-third forearm BMD (FaBMD) was measured using a peripheral instantaneous x-ray imager. Anthropometry, fasting plasma glucose (FPG), serum adiponectin, leptin and 25-hydroxyvitamin D (25(OH)D) were measured. Traditional food intakes were surveyed. Data were analysed using mixed model ANOVA and regression models. The median age was 53 (IFG: IQR 48, 67) y and 56 (T2D: IQR 49, 63) y. Compared to normoglycemic women, FaBMD and T-scores were significantly lower in women with T2D, but not with IFG. Frequency of marine mammal intakes (ß = 0.145; 95%CI: 0.018, 0.053, p = 0.0001) positively related to FaBMD. The odds ratio of having a T-score consistent with osteoporosis was lower among women with T2D and higher BMI, while aging increased the risk. Although T2D associates with lower BMD among Inuit women, risk of osteoporosis is tempered, possibly by maintenance of a traditional lifestyle.

PO-091 5-year changes and effects of bone mineral density in 6-year-old children

Objective To explore the development and developmental characteristics of forearm bone mineral density in childhood, to understand the effects of body composition and developmental type on bone mineral density, and to provide a basis for studying the changes of human forearm bone mineral density.&#x0D; Methods Bone development follow-up study of Huilongguan primary school affiliated to Capital Normal University in 2013 enrolled in primary school for five years (2013, 2014, 2015, 2016 and 2017), tracking test indicators: height, weight, body fat composition, forearm bone density. Bone age testing was conducted in 2013 and 2017. Data were analyzed for students who were 6 years old at the end of the first year of the test date. The effective data was 297 (age 6.6 ± 0.2 years), including 147 boys and 150 girls.&#x0D; Results 1. Forearm bone mineral density(g/cm2)for the boys and girls were 0.237±0.061 and 0.221±0.059 for children aged 6, 0.220±0.042 and 0.201±0.032 for 7 years old children, 0.219±0.040 and 0.198±0.038 for 8 years old children, 0.236±0.051 and 0.208±0.043 for 9 years old children ,while 0.237±0.044 and 0.213±0.047 when children were 10 years old. An independent sample t-test was performed on bone mineral density in boys and girls. At 7 years, 8 years, 9 years, and 10 years, the bone mineral density of boys was greater than that of girls, and the difference was statistically significant (p&lt;0.05). 2. The same batch of child follow-up studies found that girls and boys aged 6 to 8 had a decreasing trend, and the decline of girls was greater than that of boys; girls and boys aged 8 to 10 have risen again, and the increase in girls is less than that of boys; body weight and BMI are factors influencing the forearm bone density of children aged 6-10 years. Height changes and weight changes have a certain effect on changes in forearm bone density. 3. There was no statistically significant difference between bone mineral density and height. The partial correlation with body weight was statistically significant between 6 and 10 years old, r=0.200 (p&lt;0.01), r=0.124 (p&lt;0.05), r =0.176 (p&lt;0.01), r=0.110 (p&lt;0.05), r=0.162 (p&lt;0.05); the partial correlation with BMI was statistically significant, r=0.223 (p&lt;0.01), r =0.134 (p&lt;0.01), r=0.183 (p&lt;0.01), r=0.150 (p&lt;0.05)r=0.208 (p&lt;0.01); As for the relationships between body fat ratio、FFM ratio and bone mineral density, there are no partial correlations(p＞0.05). 4. The partial correlation between bone mineral density change and height change (6-8 years old) and body weight change (8-10 years old) was statistically significant, r=-0.138 (p&lt;0.05), r=0.178(p &lt;0.01), the change in bone mineral density of the children with highest 25% and the lowest 25% with different indicators, only the height of the independent sample t-test results was statistically significant. 5. After multiple stepwise linear regression model. At the age of 7, the adjustment of R2 is the highest. The gender and body mass index entered the model. 6. The overweight and obesity rate of 6-10 years old is more than 40% for boys and over 30% for girls. The obesity rate for boys aged 6 to 10 is reduced from 21.9% to 23.8%; the obesity rate for girls is from 20.3% to 17.3%.&#x0D; Conclusions The same batch of child follow-up studies found that girls and boys aged 6 to 8 had a decreasing trend, with the decline of girls greater than that of boys; girls and boys between the ages of 8 and 10 were rising again, and the increase in girls was less than that of boys; Weight and BMI are factors influencing the forearm bone mineral density of children aged 6-10 years. Height changes and weight changes have a certain effect on changes in forearm bone density.

Optimal Dose of Calcium for Treatment of Nutritional Rickets: A Randomized Controlled Trial.

Calcium supplementation is indicated for the treatment of nutritional rickets. Our aim was to determine the optimal dose of calcium for treatment of children with rickets. Sixty-five Nigerian children with radiographically confirmed rickets were randomized to daily supplemental calcium intake of 500 mg (n = 21), 1000 mg (n = 23), or 2000 mg (n = 21). Venous blood, radiographs, and forearm areal bone density (aBMD) were obtained at baseline and at 8, 16, and 24 weeks after enrollment. The primary outcome was radiographic healing, using a 10-point radiographic severity score. The radiographic severity scores improved in all three groups, but the rate of radiographic healing (points per month) was significantly more rapid in the 1000-mg (-0.29; 95% confidence interval [CI] -0.13 to -0.45) and 2000-mg (-0.36; 95% CI -0.19 to -0.53) supplementation groups relative to the 500-mg group. The 2000-mg group did not heal more rapidly than the 1000-mg group. Of those who completed treatment for 24 weeks, 12 (67%), 20 (87%), and 14 (67%) in the 2000-mg, 1000-mg, and 500-mg groups, respectively, had achieved a radiographic score of 1.5 or less (p = 0.21). Serum alkaline phosphatase decreased and calcium increased similarly in all groups. Forearm diaphyseal aBMD improved significantly more rapidly in the 2000-mg group than in the 500-mg and 1000-mg groups (p < 0.001). Daily calcium intakes of 1000 mg or 2000 mg produced more rapid radiographic healing of rickets than 500 mg, but 2000 mg did not have greater benefit than 1000 mg. Some children require longer than 24 weeks for complete healing of nutritional rickets. © 2016 American Society for Bone and Mineral Research.

Long‐chain Polyunsaturated Fatty Acid Status Associates with Bone Mass in Overweight and Obese Children

Children who are obese are at increased risk of fractures. However, linkages to possible nutritional imbalances are unclear. Experimental studies suggest long‐chain polyunsaturated fatty acids (LCPUFA) such as arachidonic acid (AA C20:4 n6) modulate bone mass in a biphasic manner, yet it is uncertain whether this is observed in humans. This study examined the relationship between LCPUFA status and bone mass in overweight and obese (OvOb) children. Participants (n=119, 9.28 ± 1.89 y, BMI‐z 3.03 ± 1.02) were assessed for bone mass with DXA (Hologic Discovery). Fatty acid profile was measured in red blood cells (RBC) using gas chromatography. A generalized linear model was used to determine relationships between LCPUFA in RBC and bone outcomes with adjustments for Tanner stages and BMI. Saturated fatty acids palmitate (C16:0) and stearate (C18:0) inversely related to lumbar spine bone mineral density (r=‐0.18 and ‐0.22 respectively, p&lt;0.05); while the omega‐3 fatty acid α‐linoleneate (ALA, C18:3 n3) positively related to whole body, total hip, ultra‐distal and mid forearm bone area, mineral content (BMC) and density (r=0.21 to 0.31, p&lt;0.05). When children were divided into three groups by AA tertiles (cutoffs by 33rd and 67th percentile of % total FA) and compared with MIXED model ANOVA, those in the second tertile had greater forearm bone area and BMC than those in the first or third tertiles (Table 1), indicating higher AA levels may not confer additional benefits in bone growth and mineral accrual. These data suggest LCPUFA may play important roles in modulating bone mass during growth in OvOb children. 1st tertile (n=39) [4.67‐7.51%] 2nd tertile (n=35)[7.52‐ 8.42%] 3rd tertile (n=45)[8.44‐14.06%] Ultra‐dista Area (cm2) 4.09 ± 0.64a 4.67 ± 0.67b 4.29 ± 0.63a BMC (g) 1.32 ± 0.05 1.51 ± 0.09 1.38 ± 0.07 Mid Area (cm2) 7.50 ± 0.47ab 9.21 ± 0.55a 7.75 ± 0.32b BMC (g) 3.05 ± 0.22a 4.02 ± 0.34b 3.31 ± 0.19a 1/3 distal Area (cm2) 4.33 ± 0.10a 4.74 ± 0.10b 4.38 ± 0.06a BMC (g) 2.11 ± 0.09 2.43 ± 0.13 2.28 ± 0.09

Prostate cancer treated with androgen deprivation therapy has consequences for bone

From the meta-analysis by Lassemillante et al. [1] in this issue of the Journal, it is clear that there is a high prevalence of osteoporosis and low bone mass (osteopenia) by dual energy x-ray absorptiometry (DXA) in men treated with androgen deprivation therapy (ADT) for prostate cancer. While the prevalence of osteoporosis varied among the cited studies, there is no doubt that the impact of ADT on bone mineral density, and therefore, fracture risk is underappreciated by patients and medical professionals. ADT may include analogs of gonadotropin releasing hormone (GnRH), androgen receptor blockers, or a combination of the two. In the past and rarely today, orchiectomy has been used to lead to a hypogonadal state. It is important to note that the dramatic decrease of testosterone by GnRH analogs or orchiectomy also leads to very low levels of estradiol, which is of particular import for bone in older men [2]. Prostate cancer patients treated with only androgen receptor blockade have less loss of bone than those treated with GnRH analogs or combined therapy [3]. Lassemillante et al. [1] also comment on the addition of forearm bone density, usually the distal 1/3 radius, as an important measure of bone density in men on ADT. In older men, degenerative changes in the spine commonly prevent interpretation of bone density. In some studies [4, 5], an additional 15 % or more of patients are diagnosed with osteoporosis or low bone mass by the addition of radius bone density. This suggests that all older men on ADT should have forearm bone density done routinely. An additional method to identify ADT patients at risk for fracture would be to use the FRAX calculation. Saylor et al. [6] found that FRAX identified additional men at risk for fracture—beyond those found by DXA. In our own study [7] of 115 consecutive men on ADT, FRAX calculations with and without DXA produced different populations considered at risk for fracture. Finally, the International Society for Clinical Densitometry is now recommending that a white female database be used for calculating T-scores for men [8], which will lower the percentage of men with low bone mass and osteoporosis. The confusion from such varied results makes evaluation and treatment of men on ADT less likely. As pointed out by Lassemillante et al. [1], men on ADT may have sexual dysfunction, gynecomastia, and body composition changes that may increase the risk of metabolic syndrome. In addition, hot flashes/flushes and fatigue are common complaints in men on ADT. Thus, even though the risk of osteoporosis may be as high as 50 % and the risk of fracture after 5 years of ADT may be as high as 20 % [9], it is doubtful that the man on ADT will be concerned about the silent disorder osteoporosis. This is particularly disturbing because bisphosphonates [10, 11] and more recently denosumab [12] have been shown to improve bone mineral density and in the case of denosumab [12] decrease morphometric vertebral fractures. Toremefine [13], an estrogen agonist/antagonist has also been shown to decrease morphometric vertebral fractures in men on ADT. Hence, as in other causes of secondary osteoporosis in men, such as glucocorticoid-induced osteoporosis [14], little attention is paid to the high fracture risk despite the R. A. Adler (&) Endocrinology (111P), McGuire Veterans Affairs Medical Center, 1201 Broad Rock Boulevard, Richmond, VA 23249, USA e-mail: robert.adler@va.gov

The sixth survey of the Tromsø Study (Tromsø 6) in 2007–08: Collaborative research in the interface between clinical medicine and epidemiology: Study objectives, design, data collection procedures, and attendance in a multipurpose population-based health survey

To provide a synopsis of the sixth survey of the Tromsø Study, Tromsø 6, objectives and new target areas, study design, follow-up studies, data collection, attendance, and participant characteristics. The Tromsø Study, initiated in 1974, is an epidemiological, prospective study of health conditions and chronic diseases, and a resource for the surveillance of disease risk factors. The purpose of Tromsø 6 (2007-08) was to collect novel and repeated measurements of exposure data and to assess levels of disease risk factors. Tromsø 6 included a main study that comprised two screening visits and several follow-up studies. Main study data collection: First visit (n=12,984): questionnaires, interviews, measurements of height, weight, hip and waist circumference, heart rate, blood pressure, forearm bone density, grip strength, pain sensitivity measurements, and blood and hair samples and nose and throat swab cultures. Second visit (n=7307): sampling of biological specimens (blood, urine, nose and throat swab cultures) and clinical examinations (12-lead electrocardiography, cognitive tests, visual acuity test, retinal photography, carotid ultrasound, spirometry, dual-energy X-ray absorptiometry, and echocardiography. A total of 12,984 participants aged 30-87 years were examined. The attendance rate was 66%, lower than in previous Tromsø Study surveys. The attendance was lowest in the youngest and oldest, those invited for the first time, and lower in men than women. The completion of the survey with this comprehensive data collection went satisfactorily. The decreasing attendance rate calls for new recruitment strategies and optimisation of the study organisation to facilitate attendance.

Cut-off values of distal forearm bone density for the diagnosis of central osteoporosis in black postmenopausal South African women

Background: The objective of this study was to establish a triage cut-off point or threshold for peripheral bone mineral density (BMD), applicable to black postmenopausal women, and that could be used as a screening method to differentiate between women with normal BMD, and those with possible central osteoporosis. This was a cross-sectional study design conducted in the North West province. Central and peripheral BMD was measured in 184 black, urban postmenopausal women. Method: Receiver operating curves (ROC) analysis was used to establish cut-off points. Sensitivity, specificity, positive and negative predictive value, odds ratios and likelihood ratios were determined. Results: The results showed a prevalence rate of 41.3% for central osteoporosis. The area under the curve (AUC) for osteoporosis at the hip was 0.818, and for the spine, it was 0.771. Using the optimum cut-off point (0.371 g/cm2 ), our results showed a misclassification rate of ≈ 49% for spine osteoporosis, and a negative predictive value of 0.825. Women who had a forearm BMD below this threshold were ~10 times more likely to have osteoporosis of the spine. Conclusion: We recommend using 0.371 g/cm2 as a cut-off point to differentiate between women who have normal BMD, and those with possible osteoporosis of the spine.

Prevention of nutritional rickets in Nigerian children with dietary calcium supplementation

Nutritional rickets in Nigerian children usually results from dietary calcium insufficiency. Typical dietary calcium intakes in African children are about 200mg daily (approximately 20–28% of US RDAs for age). We sought to determine if rickets could be prevented with supplemental calcium or with an indigenous food rich in calcium. We enrolled Nigerian children aged 12 to 18months from three urban communities. Two communities were assigned calcium, either as calcium carbonate (400mg) or ground fish (529±109mg) daily, while children in all three communities received vitamin A (2500IU) daily as placebo. Serum markers of mineral homeostasis and forearm bone density (pDEXA) were measured and radiographs were obtained at enrollment and after 18months of supplementation. The overall prevalence of radiographic rickets at baseline was 1.2% and of vitamin D deficiency [serum 25(OH)D<12ng/ml] 5.4%. Of 647 children enrolled, 390 completed the 18-month follow-up. Rickets developed in 1, 1, and 2 children assigned to the calcium tablet, ground fish, and control groups, respectively (approximate incidence 6.4/1000 children/year between 1 and 3years of age). Children who developed rickets in the calcium-supplemented groups had less than 50% adherence. Compared with the group that received no calcium supplementation, the groups that received calcium had a greater increase in areal bone density of the distal and proximal 1/3 radius and ulna over time (P<0.04). We conclude that calcium supplementation increased areal bone density at the radius and ulna, but a larger sample size would be required to determine its effect on the incidence of rickets.

Osteoporosis in Men: What has Changed?

Osteoporosis in men is finally receiving some attention; it has been realized that men are more likely to die after hip fracture. Methods for screening men for osteoporosis include dual energy x-ray absorptiometry and use of fracture risk calculators such as FRAX (World Health Organization) and the Garvan nomogram. Evaluation of men will often identify secondary causes of osteoporosis as well as multiple risk factors. Alendronate, risedronate, zoledronic acid, and teriparatide are US Food and Drug Administration (FDA)--approved therapy for men. Men on androgen deprivation therapy (ADT) are at high risk for bone loss and fracture, and all the bisphosphonates have been shown to increase bone density. The new antiresorptive drug, denosumab, although FDA-approved only for postmenopausal women, has been shown in a study of men on ADT to increase bone density in spine, hip, and forearm and decrease vertebral fractures on x-ray. Thus, there is great progress in osteoporosis in men, and recognition of its importance is increasing.

Effects of cadmium on forearm bone density after reduction of exposure for 10 years in a Chinese population

The main focus of this study was to evaluate long term effects of cadmium on forearm bone mineral density after stopping ingestion of cadmium-polluted rice for 10 years in a Chinese population. A total of 532 persons (338 women and 194 men), living in control, moderately and heavily polluted areas, were included in this study. The residents living in the polluted area ceased ingesting cadmium-polluted rice in 1996. All participants were require to answer a questionnaire and the bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) at the proximal radius and ulna. Samples of urine and blood were collected for determination of cadmium in urine (UCd) and blood (BCd).The BMD of subjects living in the heavily polluted area was significantly lower than that of those living in control area in both men and women ( p < 0.01). For the people living in the moderately polluted area, only the women's BMD was greatly lower compared to that in the control area ( p < 0.05). The BMD declined with the increasing BCd and UCd in both sexes, especially in the highest level (BCd > 5 µg/L, UCd > 10 µg/g crea) groups ( p < 0.01). It was found that there were significant differences in the prevalence of osteoporosis among the different areas ( χ 2 = 13.046, p = 0.0003) and different UCd groups ( χ 2 = 4.511, p = 0.0337) in women, but not in men ( χ 2 = 0.962, p = 0.3268; χ 2 = 1.906, p = 0.1675). But a significant difference exists in the prevalence of osteoporosis among different BCd groups in both genders ( χ 2 = 9.304, p = 0.00229, in women; χ 2 = 4603, p = 0.0319, in men). This study suggested that cadmium could play a long-term role on bone and more attention should be paid to cadmium effects on bone metabolism after reduction of exposure.

Changes in bone mineral density 10 years after marked reduction of cadmium exposure in a Chinese population

The main focus of this study was to evaluate the long-term effects of Cd on forearm bone mineral density after the cessation of the ingestion of Cd-polluted rice. A total of 458 persons (294 women, 164 men) from three Cd exposure areas (low, moderately, and heavy) participated in this study. Those living in the moderate and heavy exposure areas ceased ingesting Cd-polluted rice (0.51 and 3.7mg/kg, respectively) in 1996 (10 years prior to present analysis). The participants completed a questionnaire and bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) at the proximal radius and ulna. The changes and change percentage in forearm bone density and the prevalence of osteoporosis between 1998 and 2006 were used as markers of bone recovery. The Cd concentrations in urine (UCd) and blood (BCd) in 1998 were used as Cd exposure markers. The values of the BMD change and change percentage of groups in which UCd was above 5microg/g creatinine (microg/g crea) and BCd was above 10microg/L were significantly higher than those of the low-exposure groups (in women, p<0.001; in men, p>0.05). The BMD change and change percentage correlated positively with the UCd and BCd (in women, p<0.01; in men, p>0.05). Analysis of the Z-score revealed that the prevalence of osteoporosis in 2006 was higher than that in 1998 and increased along with the level of UCd and BCd in both women and men, especially for those subjects with the higher BCd [BCd>5microg/L, OR=3.45 (0.95-13.6); BCd>10microg/L, OR=4.51(1.57-13.54)] and UCd [UCd>10microg/g crea, OR=4.74 (1.82-12.81)] in women. It is concluded that decreasing dietary cadmium exposure at the population level is not associated with bone recovery at the individual level, and the adverse bone effects of Cd exposure persisted after the main source of Cd exposure had been blocked, especially in women.

Bone Resorption and Environmental Exposure to Cadmium in Women: A Population Study

BackgroundEnvironmental exposure to cadmium decreases bone density indirectly through hypercalciuria resulting from renal tubular dysfunction.ObjectiveWe sought evidence for a direct osteotoxic effect of cadmium in women.MethodsWe randomly recruited 294 women (mean age, 49.2 years) from a Flemish population with environmental cadmium exposure. We measured 24-hr urinary cadmium and blood cadmium as indexes of lifetime and recent exposure, respectively. We assessed the multivariate-adjusted association of exposure with specific markers of bone resorption, urinary hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP), as well as with calcium excretion, various calciotropic hormones, and forearm bone density.ResultsIn all women, the effect sizes associated with a doubling of lifetime exposure were 8.4% (p = 0.009) for HP, 6.9% (p = 0.10) for LP, 0.77 mmol/day (p = 0.003) for urinary calcium, –0.009 g/cm2 (p = 0.055) for proximal forearm bone density, and –16.8% (p = 0.065) for serum parathyroid hormone. In 144 postmenopausal women, the corresponding effect sizes were –0.01223 g/cm2 (p = 0.008) for distal forearm bone density, 4.7% (p = 0.064) for serum calcitonin, and 10.2% for bone-specific alkaline phosphatase. In all women, the effect sizes associated with a doubling of recent exposure were 7.2% (p = 0.001) for urinary HP, 7.2% (p = 0.021) for urinary LP, –9.0% (p = 0.097) for serum parathyroid hormone, and 5.5% (p = 0.008) for serum calcitonin. Only one woman had renal tubular dysfunction (urinary retinol-binding protein > 338 μg/day).ConclusionsIn the absence of renal tubular dysfunction, environmental exposure to cadmium increases bone resorption in women, suggesting a direct osteotoxic effect with increased calciuria and reactive changes in calciotropic hormones.

A three-year longitudinal evaluation of the forearm bone density of users of etonogestrel- and levonorgestrel-releasing contraceptive implants

BackgroundThe aim of this study was to evaluate bone mineral density (BMD) at baseline and at 18 and 36 months of use of etonogestrel (ENG)-and levonorgestrel (LNG)-releasing contraceptive implants. This is a continuation of a previous study in which BMD was evaluated at baseline and at 18 months of use.MethodsA total of 111 women, 19–43 years of age, wererandomly allocated to use one of the two implants. At 36 months of follow-up, only 36 and 39 women were still using the ENG- and LNG-releasing implants, respectively. BMD was evaluated at the distal and at the ultra-distal radius of the non-dominant forearm using dual-energy X-ray absorptiometry.ResultsThere was no difference in the BMD of users of either implant at 18 and at 36 months. BMD was significantly lower at 18 and at 36 months at the distal radius in both groups of users compared to pre-insertion values; however, no difference was found at the ultra-distal radius.ConclusionWomen 19–43 years of age using either one of these two contraceptive implants for 36 months had lower BMD values at the distal radius compared to pre-insertion values; however, no difference was found at the ultra-distal radius.

Height loss, forearm bone density and bone loss in menopausal women: a 15-year prospective study. The Nord-Trøndelag Health Study, Norway

In a population-based cohort of 1,421 women 45-60 years old followed for 15.5 years, 71% of the women had lost height. Height loss was associated with low forearm bone density and increased bone loss, but high body weight and oestrogen therapy were protective factors. Increased height loss indicates a generalized state of bone loss. The degree of height loss and its association to forearm bone mineral density (BMD) and bone loss was investigated in a population-based cohort of middle-aged women followed for more than 15 years. Among 8,856 women aged 45-60 years attending the first HUNT Study, Norway (1984-86), a 35% random sample was invited to forearm densitometry 11.3 years later (HUNT 2, 1995-97), and 2,188 attended (78.3%). In 2001, 15.5 years since baseline, all were invited to follow-up densitometry and height measurement. A total of 71.2% and 17.4% of the 1,421 women attending had lost >1 cm and >3 cm of height since baseline, respectively. Women aged >or= 64 years at HUNT 2 had a relative risk (RR) for height loss >3 cm of 3.1 (95% CI 2.2, 4.3) compared to women <64 years. A strong and negative association was found between height loss and forearm BMD, adjusted for time since menopause. A high rate of height loss was associated to increased forearm bone loss. High body weight, oestrogen treatment and good self-rated health were protective against height loss. Height loss is frequent in middle-aged women, and increased height loss indicates a generalized state of bone loss.

Detecting Novel Bone Density and Bone Size Quantitative Trait Loci Using a Cross of MRL/MpJ and CAST/EiJ Inbred Mice

Most previous studies to identify loci involved in bone mineral density (BMD) regulation have used inbred strains with high and low BMD in generating F(2) mice. However, differences in BMD may not be a requirement in selecting parental strains for BMD quantitative trait loci (QTL) studies. In this study, we intended to identify novel QTL using a cross of two strains, MRL/MpJ (MRL) and CAST/EiJ (CAST), both of which exhibit relatively high BMD when compared to previously used strains. In addition, CAST was genetically distinct. We generated 328 MRL x CAST F(2) mice of both sexes and measured femur BMD and periosteal circumference (PC) using peripheral quantitative computed tomography. Whole-genome genotyping was performed with 86 microsatellite markers. A new BMD QTL on chromosome 10 and another suggestive one on chromosome 15 were identified. A significant femur PC QTL identified on chromosome 9 and a suggestive one on chromosome 2 were similar to those detected in MRL x SJL. QTL were also identified for other femur and forearm bone density and bone size phenotypes, some of which were colocalized within the same chromosomal positions as those for femur BMD and femur PC. This study demonstrates the utility of crosses involving inbred strains of mice which exhibit a similar phenotype in QTL identification.

Bone density and bone area in Canadian Aboriginal women: the First Nations Bone Health Study

Canadian Aboriginal women are at increased risk of fracture compared with the general population. There is disproportionately reduced bone density in Aboriginal women as compared to white females of similar age. A random age-stratified (25-39, 40-59 and 60-75) sample of Aboriginal women (n=258) and white women (n=181) was recruited. All subjects had calcaneus and distal forearm bone density measurements, and urban participants (n=397 [90.4%]) also had measurements of the lumbar spine, hip and total body. Unadjusted measurements were similar in the two groups apart from the distal forearm which showed a significantly lower mean Z-score in the Aboriginal women (p=0.03). Aboriginal women were heavier than white women (81.0+/-18.0 kg vs. 76.0+/-18.0 kg, p=0.02). Weight was directly associated with BMD at all measurement sites (p<0.00001) and potentially confounded the assessment of ethnicity on bone mass measurements. Weight-adjusted ANCOVA models demonstrated significantly lower bone density in Aboriginal than white women for the calcaneus, distal forearm, and total body (all p<0.05), but not at the other sites. ANCOVA models (adjusted for age, height and weight) were used to explore differences in bone area and bone mineral content (BMC). There was a significant effect of ethnicity on bone area with Aboriginal women having larger adjusted mean values than white women (lumbar spine p=0.038, total hip p=0.0004, total body p=0.020). In contrast, there was no detectable effect of ethnicity on BMC (all p>0.2). We identified significant site-specific differences in age-and weight-adjusted bone density for Aboriginal and white women. Larger bone area, rather than a reduction in BMC, appeared to be primarily responsible. Further work is needed to define how these differences in bone density and geometry affect indices of bone strength.

Lifestyle factors and forearm bone density in young Greek men

The aim of this study was to evaluate the effects of dietary factors (calcium, proteins, alcohol, coffee and tea intake), exercise, sunlight exposure and immobilization on bone mineral content (BMC) and bone mineral density (BMD) in young men. We examined a group of 300 healthy men, aged 18-30. Mean weight was 80-81 kg (53-125 kg range) and height 179 cm (160-195 cm range). Distal BMC (dBMC), distal BMD (dBMD) and ultradistal BMD (udBMD) at the radius were measured by single X-ray absorptiometry (Osteometer DTX). The data concerning lifestyle factors were obtained through a questionnaire. The 300 men were divided in four groups according to calcium intake, four groups taking into account protein and three groups alcohol intake. There also were five groups of exercise level, six groups of sun exposure and two groups of duration of immobilization. In the group with the lowest levels of calcium intake (< 400 mg/day), dBMD and udBMD were lower than in the other groups of calcium intake (P = 0.002). dBMC and udBMD were lower (P = 0.043 and 0.015, respectively) in subjects with low physical activity (< 2 h/week), whereas dBMC and udBMD were higher (P < 0.0005) in subjects with frequent sun exposure (group labelled 'very often'). Multiple regression analysis on bone mineral density of the forearm showed that, calcium intake, exercise and sunlight were also independent predictors of bone mass. No significant correlation between the other examined factors and BMD or BMC was detected. Calcium intake, exercise level and sun exposure showed a statistically significant correlation with distal BMD and BMC in young adult men.