Body Bone Mineral Density Z-score Research Articles

Associations of ethnicity, skin tone, and genome-wide sequencingwith bone mineral density in adolescents.

Dual-energy x-ray absorptiometry reference data designate Black and non-Black categories, as higher BMD has been documented among Black youth. We examined associations of race, skin tone, and genetic factors with bone mineral density (BMD). 557 adolescents were followed longitudinally. Exposures included race, skin tone, and principal components (PC) from genome-wide arrays. Total body BMD Z-score (BMD-Z) was the primary outcome using linear regression. 359 adolescents identified as non-Hispanic White (NHW) and 75, non-Hispanic Black (NHB). BMD-Z was higher in NHB vs. NHW (β: 0.92 units, 95% CI: 0.64, 1.19) or those with darker skin (0.79, 95% CI: 0.49, 1.08 for brown vs. medium). The first genetic PC (PC1) correlated with identification as NHB. PC1 was associated with higher BMD-Z (0.09, 95% CI: 0.06, 0.12), even after including race (0.07, 95% CI: 0.00, 0.14) or skin tone (0.10, 95% CI: 0.05, 0.15); both race (0.26, 95% CI: -0.49, 1.01 for NHB vs. NHW) and skin tone (-0.08, 95% CI: -0.59, 0.44 for brown vs. medium) no longer predicted BMD-Z after adjustment for PC1. Genetic similarity was robustly associated with BMD, prompting a reevaluation of adolescent BMD reference data to exclude the consideration of race. Current bone density reference databases include a binary assignment of patients into "Black" and "non-Black" categories, as a higher BMD has been documented among those identifying as Black compared with individuals of other racial and ethnic backgrounds. This study found genetic similarity to be more strongly associated with bone density by dual-energy x-ray absorptiometry than race or skin tone. These data emphasize a need to reevaluate how bone density measurements are interpreted, including exploring reference data that exclude the consideration of race.

Assessment of Relative Energy Deficiency in Sport (REDs) Risk among Adolescent Acrobatic Gymnasts.

Energy imbalance exposes athletes to relative energy deficiency in sports (REDs) syndrome. Data on energy consumption, REDs, and bone mineral density (BMD) in adolescent acrobatic gymnasts, especially in males, are scarce. Our aim was to examine the eating habits, energy balance, body composition, and BMD of these athletes. In this study, 18 healthy adolescents participating in competitive acrobatic gymnastics completed a questionnaire, underwent a dual-energy X-ray absorptiometry scan (DXA), received a food log, and had their activities monitored for 3 days. Eighteen acrobats were enrolled (mean age: 14.3 ± 1.2 years; males: 6/18). The mean total body BMD Z-score was 0.4 ± 1.0. Top-position acrobats (7/18) had significantly lower total body BMD Z-scores than base-positioned acrobats (-0.2 ± 0.3 vs. 0.8 ± 0.3, p = 0.032), though their forearms were not significantly different (0.2 ± 0.5 vs. 0.8 ± 0.7, p = 0.331). No sex differences were found for BMD Z-scores, BMI, or energy availability. The BMD parameters of the acrobats were within the normal range for a healthy pediatric population, although three had low BMDs (<-1 SD) for healthy athletes. Total body and LS BMD Z-scores were significantly lower in top-position athletes compared to base-position athletes. These findings suggest personalized (top vs. base) training programs (high-impact training) that may achieve better health outcomes.

Bone Density in Children with Hypermobility Spectrum Disorder Compared to Children with Benign Hypermobility

Background: Hypermobility spectrum disorder (HSD), likely a multifactorial condition characterized by musculoskeletal pain, joint instability, and reduced bone mineral density (BMD), is the focus of this study. Objectives: The aim of this study was to assess and compare bone density in children diagnosed with HSD and those with benign hypermobility. Methods: This case-control study involved 73 pediatric patients diagnosed with hypermobility spectrum disorder and benign hypermobility, who were referred to the Rheumatology clinic of Mofid Hospital in Tehran between February and November 2022. Bone mineral density was measured using Z-scores from L1-L4 and the whole body less head via dual-energy X-ray absorptiometry (DEXA). Results: Significant differences were observed in the frequency distribution of spine BMD Z-scores between the two groups (P = 0.002). There was no significant correlation between spine and whole body BMD Z-scores with age and gender (P &gt; 0.05). A notable correlation was found between spine and whole body BMD Z-scores (P &lt; 0.001 and r = 0.64). Among the HSD group, 18 patients (81.8%) had normal BMD, while 4 patients (18.2%) exhibited low bone density, with no cases of osteoporosis. In contrast, osteoporosis was observed in 7.3% of patients in the benign hypermobility group. Conclusions: Given the high prevalence of osteoporosis in patients with benign hypermobility, clinicians should be vigilant for tendencies toward osteopenia when treating such patients.

Bone Density in Transgender Youth on Gender-Affirming Hormone Therapy.

Some transgender youth are treated with gonadotropin-releasing hormone agonists (GnRHa) followed by testosterone or estradiol, which may impact bone mineral density (BMD). This cross-sectional study of transgender youth (n = 56, aged 10.4-19.8 years, 53% assigned female at birth [AFAB]) utilized total body dual-energy x-ray absorptiometry to evaluate BMD Z-scores, and associations between GnRHa duration, body mass index (BMI), and BMD. Participants on GnRHa alone (n = 19, 14 assigned male at birth [AMAB], 5 AFAB) at the time of the study visit were 13.8 [12.8, 15.3] (median [IQR]) years old, had been on GnRHa for 10 [5.5, 19.5] months, and began GnRHa at age 12 [10.4, 12.6] years. Total body BMD Z-score for individuals on GnRHa monotherapy was -0.10 [-0.8, 0.4] (AFAB, female norms) and -0.65 [-1.4, 0.22] (AMAB, male norms). AFAB participants (n = 21) on testosterone were age 16.7 [15.9, 17.8] years, had been on testosterone for 11 [7.3, 14.5] months, and started testosterone at age 16 [14.8, 16.8] years; total body BMD Z-score -0.2 [-0.5, 0] (male norms) and 0.4 [-0.2, 0.7] (female norms). AMAB participants (n = 16) were age 16.2 [15.1, 17.4] years, had been on estradiol for 11 [5.6, 13.7] months, and started estradiol at age 16 [14.4, 16.7] years; total body BMD Z-score -0.4 [-1.1, 0.3] (male norms) and -0.2 [-0.7, 0.6] (female norms). BMD Z-score was negatively correlated with GnRHa duration (male norms: r = -0.5, P = .005; female norms: r = -0.4, P = .029) and positively correlated with BMI (male norms: r = 0.4, P = .003; female norms: r = 0.4, P = .004). In this cross-sectional cohort, total body BMD Z-scores were slightly below average, but lowest in the AMAB group on GnRHa monotherapy.

Risk factors affecting hip fracture patterns in an elderly Korean patient population.

Hip fracture in the elderly patient population, particularly the Korean patient cohort, is one of the most serious complications of osteoporosis and currently increasing alongside age. In this study, we attempted to identify various factors that could either indicate the risk for an intertrochanteric or femoral neck fracture in an osteoporotic Korean hip fracture patient cohort ≥ 65 years old. A retrospective analysis of 168 patients was performed for those who underwent surgical treatment for either an intertrochanteric or femoral neck fracture at Daegu Catholic University Medical Center from January 2013 to December 2015. Inclusion criteria included patients who sustained a intertrochanteric or femoral neck fracture between the designated time frame, ≥65 years old, and of Korean ethnicity. Differences between the T-score and Z-score regarding bone mineral density (BMD) and the relationship between BMD and subtype of the fracture for the intertrochanteric (n = 92) and femoral neck fracture (n = 76) groups were obtained. Demographical factors (age, sex, weight, height, and body mass index [BMI]) were analyzed as potential risk factors for intertrochanteric or femoral neck fractures using software. Of the total 168 patients, mean weight and BMI values were found to be lower in the intertrochanteric fracture group (P = .033) compared to the femoral neck fracture group (P = .044). Additionally, Z-scores for the intertrochanteric fracture group were lower in the trochanter (P = .030), intertrochanteric (P = .029), and Ward's triangle (P = .029) regions. Regarding the intertrochanteric fracture group, the A3 subgroup showed lower T-scores of the trochanteric region than the A1 fracture subgroup (P = .010). In an elderly Korean hip patient cohort, lower body weight, BMI, and BMD Z-scores are correlated with a higher incidence of intertrochanteric fractures when compared to femoral neck hip fractures.

Low bone mineral density is found in low weight female youth with avoidant/restrictive food intake disorder and associated with higher PYY levels

BackgroundAvoidant/restrictive food intake disorder (ARFID) is a restrictive eating disorder commonly associated with medical complications of undernutrition and low weight. In adolescence, a critical time for bone accrual, the impact of ARFID on bone health is uncertain. We aimed to study bone health in low-weight females with ARFID, as well as the association between peptide YY (PYY), an anorexigenic hormone with a role in regulation of bone metabolism, and bone mineral density (BMD) in these individuals. We hypothesized that BMD would be lower in low-weight females with ARFID than healthy controls (HC), and that PYY levels would be negatively associated with BMD.MethodsWe performed a cross-sectional study in 14 adolescent low-weight females with ARFID and 20 HC 10–23 years old. We assessed BMD (total body, total body less head and lumbar spine) using dual x-ray absorptiometry (DXA) and assessed fasting total PYY concentration in blood.ResultsTotal body BMD Z-scores were significantly lower in ARFID than in HC (− 1.41 ± 0.28 vs. − 0.50 ± 0.25, p = 0.021). Mean PYY levels trended higher in ARFID vs. HC (98.18 ± 13.55 pg/ml vs. 71.40 ± 5.61 pg/ml, p = 0.055). In multivariate analysis within the ARFID group, PYY was negatively associated with lumbar BMD adjusted for age (β = -0.481, p = 0.032).ConclusionOur findings suggest that female adolescents with low-weight ARFID may have lower BMD than healthy controls and that higher PYY levels may be associated with lower BMD at some, but not all, sites in ARFID. Further research with larger samples will be important to investigate whether high PYY drives bone loss in ARFID.

Bone Mineral Density and Dickkopf-1 in Adolescents with Non-Deletional Hemoglobin H Disease

Background: Low bone mineral density (BMD) is prevalent in individuals with β-thalassemia and is associated with increased circulating dickkopf-1 concentration. These data are limited in α-thalassemia. Therefore, we aimed to determine the prevalence of low BMD and the association between BMD and serum dickkopf-1 in adolescents with non-deletional hemoglobin H disease, a form of α-thalassemia whose severity is comparable to β-thalassemia intermedia. Methodology: The lumbar spine and total body BMD were measured and converted into height-adjusted z-scores. Low BMD was defined as BMD z-score ≤ -2. Participant blood was drawn for measurement of dickkopf-1 and bone turnover marker concentrations. Results: Thirty-seven participants with non-deletional hemoglobin H disease (59% female, mean age 14.6 ± 3.2 years, 86% Tanner stage ≥2, 95% regularly transfused, 16% taking prednisolone) were included. Over one year prior to the study, mean average pretransfusion hemoglobin, ferritin and 25-hydroxyvitamin D concentrations were 8.8 ± 1.0 g/dL, and 958 ± 513 and 26 ± 6 ng/mL, respectively. When participants taking prednisolone were excluded, the prevalence of low BMD at the lumbar spine and total body was 42% and 17%, respectively. BMD at both sites was correlated positively with body mass index z-score, and negatively with dickkopf-1 (all p-values <0.05). There were no correlations among dickkopf-1, 25-hydroxyvitamin D, osteocalcin and C-telopeptide of type-I collagen. Multiple regression analysis showed dickkopf-1 inversely associated with total body BMD z-score adjusting for sex, bone age, body mass index, pre-transfusion hemoglobin, 25-hydroxyvitamin D, history of delayed puberty, type of iron chelator and prednisolone use (p-value = 0.009). Conclusions: We demonstrated a high prevalence of low BMD in adolescents with non-deletional hemoglobin H disease. Moreover, dickkopf-1 inversely associated with total body BMD suggesting it may serve as a bone biomarker in this patient population.

Histologic Severity of Nonalcoholic Fatty Liver Disease Associates with Reduced Bone Mineral Density in Children.

Lower whole body bone mineral density (BMD) has been reported in children with nonalcoholic fatty liver disease (NAFLD), but potential mediators remain uncertain. To assess BMD at multiple skeletal sites in children with confirmed NAFLD and controls with obesity, adjusting for known determinants of BMD, and examine potential mediators. We assessed age-, sex-, and race-specific, and height-adjusted BMD z-scores of whole body, lumbar spine, hip, femoral neck and forearm by dual-energy-x-ray absorptiometry in 79 children, 8-19years old: 46 with biopsy-confirmed NAFLD [29 steatohepatitis (NASH)/17 fatty liver (NAFL)] and 33 controls without liver disease. We compared BMD z-scores by multivariable regression, adjusting for known BMD determinants and potential mediators (inflammatory and insulin resistance measures). Unadjusted mean BMD z-scores in NAFLD were similar to controls, but significantly lower in NASH vs. NAFL at all sites. After covariate adjustment, mean forearm BMD z-score was higher in NAFL (β 0.60 ± SE 0.30, p < 0.05) and lower in NASH (β -0.49 ± SE 0.26, p = 0.06) vs. controls (p = 0.002 for group), with similar trends at whole body and total hip; hs-CRP negatively associated with whole body and forearm BMD z-scores (p < 0.05), while visceral fat area negatively associated with femoral neck (p < 0.05). Only three children had clinically low whole body BMD z-scores (< -2), one per group (control, NAFL and NASH). NASH, but not NAFL, may be associated with increased risk of reduced BMD in children. Systemic inflammation, independent of body composition and load bearing, may mediate reduction in BMD in NASH.

Higher Peptide YY Levels Are Associated With Lower Bone Mineral Density in Low Weight Adolescent Girls With Avoidant/Restrictive Food Intake Disorder

Background: Avoidant/Restrictive Food Intake Disorder (ARFID) is a condition characterized by lack of interest in eating or food, sensory sensitivity, and/or fear of aversive consequences of eating; as opposed to the body image disturbance and fear of weight gain that characterize anorexia nervosa (AN). While appetite regulating hormones and their associations with bone mineral density (BMD) have been well studied in AN, little is known regarding BMD and its association with appetite regulating hormones in ARFID. Peptide YY (PYY), a gut derived anorexigenic hormone, acts via the Y2 receptor to inhibit osteoblastic activity in mammals. In AN, levels of PYY are higher than in healthy controls (HC) and are negatively associated with BMD. We hypothesized that similar to AN, low-weight female adolescents with ARFID would have lower BMD and higher PYY levels than in HC and that PYY levels would be inversely associated with BMD. Methods: We studied 24 adolescent females (10 low weight with ARFID and 14 HC). BMD variables were measured by Dual-Energy X-ray Absorptiometry. We performed cross sectional analysis to compare BMD and fasting PYY levels between low weight ARFID and HC and to determine the relationship between BMD and PYY levels. Results: ARFID and HC were 15.1±2.9 (mean ± SEM) and 17.1±3.8 years old, respectively (p=0.178), with mean BMI Z-scores of -1.74±0.88 kg/m2 and 0.24±0.51 kg/m2, respectively (p<0.0001). Total body BMD Z-scores were significantly lower in ARFID (-1.59±1.19, n=10) compared to HC (-0.41±1.11, n=14) (p=0.022), and lumbar BMD Z-scores were numerically lower in ARFID (-1.13±1.40, n=9) vs. HC (-0.44±0.86, n=14) (p=0.212). Mean PYY levels trended higher in ARFID (104.6±39.9 pg/ml, n=8) vs. HC (71.4±24.5 pg/ml, n=9) (p=0.054). In a combined analysis of participants with ARFID and HC, PYY levels were negatively correlated with lumbar BMD and BMD Z-scores (r=-0.52, p=0.038 and r=-0.54 p=0.031, n=16). In multivariable regression analysis, PYY remained a primary determinant of lumbar BMD after adjusting for age and height (p=0.035, β= -0.36) and a borderline significant predictor of lumbar BMD Z-scores after adjusting for height (p=0.064, β=-0.5). Similar associations were noted within the ARFID group alone, with PYY being a significant predictor of lumbar BMD (p=0.031, β=-0.97) after adjusting for age and height. Conclusion: Female adolescents with low-weight ARFID have lower BMD and a trend toward higher levels of PYY compared with HC. Increased PYY levels may contribute to the lower BMD observed in ARFID. These findings are an initial step in understanding the neuroendocrine dysregulation in low weight adolescents with ARFID, which may predict bone outcomes in this condition.

Plasma high-resolution metabolomics identifies linoleic acid and linked metabolic pathways associated with bone mineral density.

There is a considerable degree of variation in bone mineral density (BMD) within populations. Use of plasma metabolomics may provide insight into established and novel determinants of BMD variance, such as nutrition and gut microbiome composition, to inform future prevention and treatment strategies for loss of BMD. Using high-resolution metabolomics (HRM), we examined low-molecular weight plasma metabolites and nutrition-related metabolic pathways associated with BMD. This cross-sectional study included 179 adults (mean age 49.5±10.3yr, 64% female). Fasting plasma was analyzed using ultra-high-resolution mass spectrometry with liquid chromatography. Whole body and spine BMD were assessed by dual energy X-ray absorptiometry and expressed as BMD (g/cm2) or Z-scores. Multiple linear regression, pathway enrichment, and module analyses were used to determine key plasma metabolic features associated with bone density. Of 10,210 total detected metabolic features, whole body BMD Z-score was associated with 710 metabolites, which were significantly enriched in seven metabolic pathways, including linoleic acid, fatty acid activation and biosynthesis, and glycerophospholipid metabolism. Spine BMD was associated with 970 metabolites, significantly enriched in pro-inflammatory pathways involved in prostaglandin formation and linoleic acid metabolism. In module analyses, tryptophan- and polyamine-derived metabolites formed a network that was significantly associated with spine BMD, supporting a link with the gut microbiome. Plasma HRM provides comprehensive information relevant to nutrition and components of the microbiome that influence bone health. This data supports pro-inflammatory fatty acids and the gut microbiome as novel regulators of postnatal bone remodeling.

Dietary Fiber and Bone Density in Youth with Type 2 Diabetes

Abstract Objectives Assess relationships between dietary fiber and bone density in youth with type 2 diabetes, obesity, and healthy weight. Methods Cross-sectional study of youth (56% African American, 67% female) ages 10–23 years with type 2 diabetes (n = 180), obesity (BMI &amp;gt;95th; n = 226), or healthy weight (BMI &amp;lt; 85th; n = 238). Total body bone mineral density (BMD) was assessed via DXA. BMD standard deviation scores (“Z-scores”) were computed using published reference data. Dietary fiber (total, soluble, and insoluble) and total calories were assessed via 3-day food diaries, which were analyzed using the Nutrition Data System for Research. Relationships between dietary fiber and BMD Z-score were assessed using linear regression. Separate analyses were performed for total, soluble, and insoluble fiber, and each regression model included age, sex, ancestry, total calories, group, and fiber (total, soluble, or insoluble), as well as group by fiber interactions. Results BMD Z-score was greater in the type 2 diabetes and obese compared to the healthy weight group (P &amp;lt; 0.001). Total, soluble, and insoluble fiber intakes were significantly greater in the healthy weight versus obese group (all P &amp;lt; 0.05), but only marginally greater than the type 2 diabetes group (all P = 0.06–0.10). Regression analyses demonstrated positive relationships between total, soluble, and insoluble fiber intakes and BMD Z-score (all P &amp;lt; 0.05). However, significant group by fiber interactions indicated that the positive relationships between dietary fiber intakes and BMD Z-score was evident only in the healthy weight group (all P &amp;lt; 0.005). Similar relationships were observed when considering BMD Z-score adjusted for height Z-score. Conclusions Prior studies have reported a favorable influence of dietary fiber on bone mineral accrual in healthy individuals and metabolic health in adults with insulin resistance. Dietary strategies promoting increased fiber consumption warrant investigation with respect to fracture prevention and glycemic control in youth with type 2 diabetes. Funding Sources NIH-NHLBI, American Diabetes Association, and Endocrine Fellows Foundation.

Plasma High-Resolution Metabolomics Identifies Linoleic Acid and Linked Metabolic Pathways Associated with Bone Mineral Density

Abstract Objectives There is a considerable degree of variation in bone mineral density (BMD) within populations. Use of plasma metabolomics may provide insight into established and novel determinants of BMD variance, such as nutrition and gut microbiome composition, to inform future prevention and treatment strategies for loss of BMD. Using high-resolution metabolomics (HRM), we examined low-molecular weight plasma metabolites and nutrition-related metabolic pathways associated with BMD. Methods This cross-sectional study included 179 adults (mean age 49.5 ± 10.3 yr, 64% female). Fasting plasma was analyzed using ultra-high-resolution mass spectrometry with liquid chromatography. Whole body and spine BMD were assessed by dual energy x-ray absorptiometry and expressed as BMD (g/cm2) or Z-scores. Multiple linear regression, pathway enrichment, and module analyses were used to determine key plasma metabolic features associated with bone density. Results Of 10,210 total detected metabolic features, whole body BMD Z-score was associated with 710 metabolites, which were significantly enriched in seven metabolic pathways, including linoleic acid, fatty acid activation and biosynthesis, and glycerophospholipid metabolism. Spine BMD was associated with 970 metabolites, significantly enriched in pro-inflammatory pathways involved in prostaglandin formation and linoleic acid metabolism. In module analyses, tryptophan- and polyamine-derived metabolites formed a network that was significantly associated with spine BMD, supporting a link with the gut microbiome. Conclusions Plasma HRM provides comprehensive information relevant to nutrition and components of the microbiome that influence bone health. This data supports pro-inflammatory fatty acids and the gut microbiome as novel regulators of postnatal bone remodeling. Funding Sources Grant support included funds NIH and VA Office of Research and Development.

OR27-04 Risk Factors For Low Baseline Bone Mineral Density In Gender Diverse Youth

BackgroundSex steroids such as testosterone and estrogen are necessary for accumulation of bone mass. Transgender youth treated with gonadotropin releasing hormone analogues (GnRHa) to block natal puberty for gender-affirming care are at risk of low bone mineral density (BMD). Previous studies indicate that transfemale patients assigned male at birth (AMAB) have low BMD at baseline, during and after GnRHa treatment despite cross hormone treatment. Transmales assigned female at birth (AFAB), however, have normal BMD at baseline that decreases upon GnRHa treatment, with normalization upon cross hormone therapy. The reason(s) for the low baseline BMD in transfemales is unclear. We aimed to assess the baseline characteristics of transgender youth at a single multidisciplinary gender clinic prior to medical intervention and determine factors associated with BMD.MethodsThis is a retrospective chart review of patients <19 years old evaluated in the gender clinic. Dual-energy x-ray absorptiometry (DXA) scans were obtained prior to initiation of GnRHa or cross-hormone therapy per Endocrine Society guidelines for the treatment of gender dysphoria. We included patients with DXA scans completed prior to initiation of treatment with GnRHa or cross gender hormones and excluded those with concurrent medical diagnoses that may affect bone density. Data collected were bone mineral density (BMD) Z-scores, anthropometric data, vitamin D and calcium levels, and calcium intake. Multivariable linear regression models were used to assess the impact of vitamin D levels, height Z-score, weight Z-score, and BMI Z-score on subtotal body BMD Z-score, adjusted for sex assigned at birth and age.ResultsSixty-four patients were included in our analysis. Of these, 73% were AMAB and 27% AFAB. Gender identity was male in 14%, female in 44%, and non-binary in 42%. Average height Z-score was 0.12, weight Z-score 0.27, and BMI Z-score 0.22 (using sex assigned at birth). Subtotal body BMD Z-scores were greater than zero in 11%, between zero and greater than -2 in 59%, and less than or equal to -2 in 30% of tested patients. AMAB patients had lower BMD Z-scores compared to those AFAB (p<0.05 for all Z-scores). There was a positive association with BMI, height, and weight Z-scores and increasing BMD Z-scores after adjusting for sex assigned at birth and age (p<0.05 for all Z-scores). Patients who consumed <2 servings of calcium per day had lower BMD Z-scores (p<0.05 for all Z-scores). Average vitamin D level was 24 ng/ml (+/- 9.5 SD) with no significant association with BMD Z-scores (adjusted for sex assigned at birth).ConclusionsPatients AMAB and patients with calcium intake of < 2 servings/day are associated with lower baseline BMD in a cohort of adolescents seen in a multidisciplinary gender clinic. Height, weight, and BMI are associated linearly with BMD Z-score, following patterns previously described in other populations.

Bone mineral density in adolescent urinary stone formers: is sex important?

Urinary stone disease (USD) is affecting a greater number of children and low bone mineral density (BMD) and increased skeletal fractures have been demonstrated in stone patients; however, the mechanism(s) driving bone disease remain unclear. This pilot study was undertaken to assess an adolescent kidney stone cohort's BMD and evaluate for an inverse correlation between BMD and urine concentration of lithogenic minerals and/or inflammatory levels. Prospective case-control study was carried out at a large pediatric center. 15 participants with USD (12-18years of age, 8 female) were matched by age, sex, and body mass index to 15 controls. Lumbar and total body BMD z-score did not differ between groups. When stone formers were separated by sex, there was a significant difference between male stone formers vs. controls total body BMD z-score (Fig. 1). BMD z-score did not significantly correlate with urine calcium, oxalate, citrate or magnesium. Higher urine IL-13 did significantly correlate with higher total body BMD z-score (r = 0.677, p = 0.018). Total body BMD z-score did significantly correlate with body mass index (BMI) as expected for the control group (r = 0.6321, p = 0.0133). However, this relationship was not present in the USD group (r = -0.1629, p = 0.5619). This is a small but hypothesis-generating study which demonstrates novel evidence of male-specific low BMD in adolescent stone formers. Furthermore, we demonstrated a positive association between urine IL-13 and total body BMD z-score USD patients as well as a lack of a positive BMD and BMI correlations in stone formers.

Bone mass and dietary intake in children and adolescents with type 1 diabetes mellitus

ObjectivesTo evaluate the bone mineral density (BMD) in children/adolescents with type 1 diabetes mellitus (T1DM) and its association with the nutritional intake, metabolic control, and physical activity level of this population. MethodsStudy including 34 patients with T1DM and 17 controls. Assessments included the participants disease history, intake of macronutrient, calcium, phosphorus and magnesium, physical activity level, total body and lumbar spine BMD and serum levels of glycated hemoglobin, vitamin D, calcium, phosphorus, magnesium, osteocalcin and C-terminal telopeptide. ResultsTotal body and lumbar spine BMD z-scores were normal in all but two participants in the T1DM group. The T1DM group had significantly lower total body BMD z-score values (p < 0.001) and levels of osteocalcin, C-terminal telopeptide, calcium, phosphorus, and magnesium. Intake of macronutrients and calcium was inadequate in both groups. Participants in the T1DM group were more sedentary (88%) and had inadequate metabolic control (91%) and low vitamin D levels (82%). Bone mass in the T1DM group was influenced by body mass index (BMI), pubertal stage, disease duration, calcium intake, and physical activity level. ConclusionsBone mass in patients with T1DM was adequate but lower than controls and was influenced by BMI, pubertal stage, disease duration, calcium consumption, and physical activity level.

Altered body composition profiles in young adults with childhood-onset inflammatory bowel disease

Background: Patients with inflammatory bowel disease (IBD) often develop alterations in body composition in terms of their proportions of lean mass and fat mass, as well as reduced bone mineral density (BMD). However, there are limited data on the skeletal muscle index (SMI) and percentage fat (fat %) for young adults with childhood-onset IBD. Our aim was to investigate the body compositions of these patients, with the focus on SMI and fat %.Methods: Body composition was estimated by dual x-ray absorptiometry for 94 young adults with childhood-onset IBD aged 18–27 years, 65 of whom had ulcerative colitis. The Z-scores for SMI, fat %, and BMD were calculated using the normative data from 1,289 individuals with corresponding age. Based on the SMI and fat % Z-scores, each patient was classified as having a body composition profile that was: (i) normal; (ii) obese (fat % Z-score >1); (iii) myopenic (SMI Z-score < −1); or (iv) myopenic-obese.Results: A higher proportion of young adults with childhood-onset IBD had a body composition profile classified as myopenic (24%) or myopenic-obese (9%), as compared to the controls (myopenic [16%, p = .016]; myopenic-obese [2%, p = .002]). Patients with the myopenic or myopenic-obese profile had significantly lower total body BMD Z-scores (−1.3 ± 0.7 and −1.4 ± 0.9, respectively) than patients with the normal profile (−0.2 ± 1.1; p < .001 and p = .004, respectively). Diagnosis of IBD in childhood represented an additional risk for low BMD, regardless of SMI Z-score.Conclusion: Young adults with childhood-onset IBD have a high risk for having altered body composition traits.SummaryYoung adults with childhood-onset IBD carry a high risk for altered body composition traits. The myopenic and myopenic-obese body composition profiles were more frequently observed in patients with IBD than controls, and these profiles were strongly associated with low BMD.

Bone turnover markers during the remission phase in children and adolescents with type 1 diabetes.

In rodents, osteocalcin (OCN) stimulates insulin production and insulin sensitivity, both important factors during partial remission in humans with type 1 diabetes (T1D). However, decreased OCN has been reported in both adult and pediatric T1D. This study aims at investigating bone turnover and partial remission in children and adolescents with recent onset T1D. Ninety-nine individuals (33% girls) were recruited within 3 months of T1D onset and examined three times, 6 months apart. Outcome variables were bone formation markers OCN and procollagen type 1 amino-terminal propeptide (P1NP) and the bone resorption marker C-terminal crosslinked telopeptide of type 1 collagen (CTX). Dependent variables included IDAA1c (surrogate marker of partial remission), total body bone mineral density (BMD) and stimulated C-peptide as representative of endogenous insulin production. OCN- and P1NP Z-scores were significantly decreased throughout the study, whereas CTX Z-scores were increased. None of the bone turnover markers changed significantly between visits. Total body BMD Z-score did not change during the study but was significantly higher than the reference population at visit 2 (P = .035). There were no differences in the bone turnover markers for those in partial remission as defined by either C-peptide or IDAA1c at any visit. The individual change in CTX Z-score was negatively associated with the increase of IDAA1c (P = .030) independent of C-peptide decline (P = .034). Bone turnover markers indicate increased bone resorption and decreased bone formation during the first year of T1D. The negative association between bone resorption and IDAA1c might represent compensatory mechanisms affecting insulin sensitivity.

Use of an aromatase inhibitor in children with congenital adrenal hyperplasia: Impact of anastrozole on bone mineral density and visceral adipose tissue.

Anastrozole, an aromatase inhibitor, has been used off-label in males with short stature to delay bone maturation. No studies have examined anastrozole's effect on bone mineral density (BMD) or body composition in children with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. Our objective was to evaluate anastrozole's effect on BMD and visceral adipose tissue (VAT) in children with CAH. Total body BMD (TBMD) and L2-L4 BMD Z-scores were adjusted for height-for-age Z-scores (TBMDHAZ and L2-L4HAZ ). Hydrocortisone doses (mg/m2 /d) were averaged over the previous year. Comparison of treated vs not treated with anastrozole used linear regression adjusting for age, pubertal status, sex, CAH type, years on hydrocortisone, BMI Z-scores and bone age Z-scores. We compared 25 children with CAH treated with anastrozole (mean age 11.3 [SD 3.0]years, 56% males) vs 31 children with CAH not treated with anastrozole (13.5 [SD 4.6], 29%). Participants underwent a pubertal exam, bone age X-ray and dual X-ray absorptiometry (DXA) scan. Average bone age Z-score of 4.3 SDs on beginning anastrozole decreased to 1.9 SDs at time of DXA exam (P=0.0004) 5.2 (SD 2.2)years later. TBMD Z-scores (P=0.51), L2-L4 BMD Z-scores (P=0.66), VAT (P=0.38), TBMDHAZ Z-scores (P=0.66) and L2-L4HAZ Z-scores (P=0.41) did not differ between children treated vs not treated with anastrozole. Anastrozole significantly reduced bone age advancement in children with CAH and advanced bone age (>2SDs) without adverse effects on BMD or VAT. Longitudinal studies of anastrozole in children with CAH are needed to validate these findings.

Oestrogen replacement improves bone mineral density in oligo-amenorrhoeic athletes: a randomised clinical trial

ObjectiveNormal-weight oligo-amenorrhoeic athletes (OAA) are at risk for low bone mineral density (BMD). Data are lacking regarding the impact of oestrogen administration on bone outcomes in OAA. Our objective was...

Bone health in adult women with ED: A longitudinal community-based study

Although Eating Disorders (ED) are known to affect bone health and development, little is known about the longitudinal effect of ED and ED behaviours on bone health in community dwelling adult women.Women (n = 3507) enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) participated in a two-phase prevalence study to assess lifetime ED and ED behaviours (fasting, restrictive eating, vomiting and misuse of medication). Crude and adjusted linear regression methods investigated the association between ED diagnoses and behaviours, and total body, hip, leg and arm bone mineral density (BMD) DXA scans at mean ages of 48 and 52 years.Lifetime occurrence of Anorexia Nervosa (AN) was associated with lower BMD Z-scores for the whole body (mean difference (MD) = −0.28; 95% CI: -0.49, −0.05), hip (MD = −0.45; 95% CI -0.74, −0.16), leg (MD = −0.28; 95% CI -0.52, −0.03) and arm (MD = −0.44; 95% CI -0.68, −0.19) compared to no ED. This effect was mostly accounted for by lowest ever BMI. In post-hoc analyses, Restrictive AN, but not Binge-Purge AN was associated with a lower total body BMD Z-scores (MD = −0.37; 95% CI -0.62, −0.12). Lifetime Fasting and Restrictive Eating were associated with low BMD of the total body, hip, arm and leg in adjusted analyses, all p < 0.05.Both lifetime ED diagnoses and ED behaviours in a large community sample were predictive of low BMD in mid-life. This study confirms that the effects of AN, fasting and restrictive eating, and low BMI on bone health seen in clinical samples also occur in community samples.