Dual-energy X-ray absorptiometry interpretation and reporting in children and adolescents: the revised 2013 ISCD Pediatric Official Positions

How to identify children with cerebral palsy at risk of low bone mineral density

AIM

Cerebral palsy is a common chronic motorically disabling condition in children. The aim of this study was to determine prevalence of low bone mineral density (BMD) in children with cerebral palsy and to examine the association between BMD with risk factors.

METHODS

Cross sectional study of children with cerebral palsy analyzing Dual X-ray Absorptiometry, blood tests, full clinical medical examination including Tanner stage and nutritional status, measurement of anthropometrics and assessment of physical activity.

RESULTS

The 81 participants were aged 2.1-17.4 years (median 9 years) and 64 out of 81 had a mild cerebral palsy (Gross Motor Function Classification System score of I-II). Mean BMD z-score was -0.2 (SD = 1.05, range -4.6 to 2.0). GMFCS score was negatively associated with BMD (p < 0.01) as higher score led to 1.43 SD lower BMD [-1.97 to -0.89]. Weight bearing activity was negatively associated with lower BMD z-score (p = 0.01), as having <30 min of weight bearing activity per day lead to 0.98 SD lower BMD [-1.75; -0.22]. Use of anti-seizure medication was negatively associated with BMD (BMD z-score 0.7 SD lower; p = 0.02, [-1.28; -0.12]). Serum vitamin D levels or fracture rates were not statistically significantly associated with BMD changes.

CONCLUSION

We found 17 % of children have low BMD regardless of motoric impairment level. GMFCS score, Sparse weight bearing activity and use of anti-seizure medicine were negatively associated to BMD. No significant associations were found with vitamin D, sex, BMI, puberty.

Assessing bone mineral density and cortical geometry using high-resolution peripheral quantitative computed tomography in pediatric survivors of high-risk neuroblastoma with severe growth failure

INTRODUCTION

Survival of children with high-risk neuroblastoma (HR-NBL) has increased with multimodal therapy. cis-Retinoic acid (cis-RA), cornerstone of HR-NBL therapy, can cause osteoporosis and premature physeal closure. This study utilized high-resolution peripheral quantitative computed tomography (HR-pQCT), for 3D measures of volumetric bone mineral density (BMD) and microarchitecture, to assess impact of HR-NBL therapy on skeletal structure.

METHODS

We prospectively enrolled 20 HR-NBL survivors and 20 age-, sex-, and race-matched healthy reference participants. We assessed leg lean mass adjusted for leg length by DXA and strength using a Biodex dynamometer. Tibia bone microarchitecture was assessed via HR-pQCT scans at 4 % of tibia length and a cortical site at 30 %. We compared tibia length (cm), cortical and trabecular vBMD (mg HA/cm3), geometric and structural parameters between groups. Linear regression models assessed group differences in bone microarchitecture adjusted for leg lean mass.

RESULTS

Compared to reference participants, tibia length was significantly shorter in HR-NBL survivors (31.6 cm [27.7,39.5] vs. 36.1 cm [30.4,40], p < 0.005), consistent with significantly lower height Z-score in the HR-NBL cohort (p < 0.001). HR-NBL survivors demonstrated lower cortical area (178.3mm2 [121.9273.5] vs. 214.6mm2 [159.4326.9], p < 0.05) and cortical perimeter (60.0 mm [51.9,82.5] vs. 68.8 mm [57.7,90.8], p < 0.01). After adjusting for tibia length, these differences were no longer significant. Total, cortical, and trabecular volumetric BMD, were not significantly different between groups. Cortical geometry and peak torque deficits were associated with muscle deficits when adjusted for leg lean mass (p < 0.001).

CONCLUSION

Bone density was not severely impacted in HR-NBL survivors. Muscle deficits persisted years after treatment and underscored cortical geometry deficits.

Brief Report: Decreased Bone Health in Children with Autism Spectrum Disorder and Avoidant Restrictive Food Intake Disorder

PURPOSE

Children with autism spectrum disorder (ASD) and food selectivity are at increased risk for nutritional deficiencies which could affect bone health.

METHODS

We report on four male patients with ASD and avoidant restrictive food intake disorder (ARFID) with significant bone conditions including rickets, vertebral compression fractures, osteopenia, and slipped capital femoral epiphyses.

RESULTS

Each patient was at risk for at least one nutritional deficiency. Two out of four patients had deficiencies in Vitamins A, B12, E, and zinc. Calcium and Vitamin D deficiency were noted in all four. Two out of four patients with Vitamin D deficiency developed rickets.

CONCLUSION

Provisional evidence suggests that children with ASD and ARFID are at elevated risk for serious adverse bone health outcomes.

Assessment of bone status and bone turnover in pediatric patients with familiar hypomagnesemia with hypercalciuria and nephrocalcinosis

Familiar hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) is a rare monogenic tubulopathy. Although some of its features are potentially harmful for skeletal homeostasis, this problem has not been systematically evaluated so far. To evaluate bone mineral density (BMD) in correlation with selected mineral parameters and bone turnover markers (BTMs) to determine the risk of bone mass loss in pediatric patients with FHHNC. The study comprised 28 FHHNC patients aged 4-18 years and 33 healthy, sex - and age matched controls. 6 FHHNC patients showed normal kidney function whereas the remaining 22 presented with CKD grade II- III (median eGFR 73 ml/min/1.73m2). In both groups, serum levels of calcium (sCa), phosphate (sP), magnesium (sMg), 25(OH)D3, 1.25 (OH)2D3, parathormone (PTH) and selected BTMs [BAP, OC, PINP, CTX-I, OPG, SCL, FGF23 and soluble Klotho protein (sKL)] as well as 24-hour urinary calcium excretion (24 h-uCa) were assessed. In addition, BMD of the lumbar spine by DXA method was evaluated. 3 (10.7%) of FHHNC patients showed low BMD (Z-score < -2). Although median Z-score was lower in FHHNC group in comparison to controls, the difference was not significant. FHHNC patients had significantly higher median PTH, 1.25(OH)2D3 and 24 h-uCa values as well as lower sMg. Of the BTMs, they had significantly higher FGF23 and CTX-I levels. CTX-I correlated positively with PTH, FGF23 and SCL but negatively with sMg. Moreover, FGF23 and PTH correlated negatively with sKL. Negative correlation between PTH and sMg was noticed. No significant correlations between measured BTMs and eGFR, sCa, sP, 25(OH)D3, 1.25 (OH)2D3 as well as 24 h uCa were found. None of BTMs significantly correlated with BMD. The results show that pediatric FHHNC patients, regardless of CKD may be at risk for increased bone resorption. Although its pathomechanism is complex, the trigger seems to be Mg depletion, aggravating secondary hyperparathyroidism and leading to the activation of osteolytic processes. However, their clinical significance is unknown, since only minority of patients show osteopenia. Therefore, follow-up of BMD and bone- related laboratory parameters including CTX-I seem to be essential in patients' monitoring, especially in adults with FHHNC.

Greater Urinary Calcium Excretion Is Associated With Diminished Bone Accrual in Youth With Type 1 Diabetes

CONTEXT

The adverse skeletal effects of type 1 diabetes (T1D) include deficient bone accrual and lifelong increased fracture risk. The contributors to impaired bone accrual in people with T1D are incompletely understood.

OBJECTIVE

To determine if urinary calcium excretion is associated with impaired bone accrual in youth with T1D and to characterize the contribution of glycemic control and markers of bone mineral metabolism to urinary calcium excretion.

DESIGN

Observational study.

PARTICIPANTS

Fifty participants with T1D aged 6 to 20 years completed a 12-month longitudinal study of bone accrual. A second cohort of 99 similarly aged participants with T1D completed cross-sectional 24-hour urine and blood collections.

MAIN OUTCOME MEASURE

Whole body less head bone mineral content (WBLH BMC) velocity Z-score and fractional excretion of calcium (FeCa).

RESULTS

Participants in the bone accrual cohort had lower WBLH BMC velocity compared to a healthy reference dataset (Z-score -0.3 ± 1.0, P = .03). FeCa was negatively associated with WBLH BMC velocity Z-score, ρ = -0.47, P = .001. In the urinary calcium excretion cohort, intact PTH (β = -0.4, P = .01), beta c-telopeptide (β = 0.35, P = .007), and either hemoglobin A1c (β = 0.08, P = .03) or urine fractional glucose excretion (β = 0.07, P = .03) were associated with FeCa in multivariable regression models that included known determinants of urinary calcium excretion.

CONCLUSION

Urinary calcium excretion was negatively associated with bone accrual in this cohort of youth with T1D. Mechanistic studies are needed to determine if interventions to reduce urinary calcium excretion could increase bone accrual and reduce skeletal fragility in people with T1D.

Pediatric Lateral Distal Femur Reference Ranges for Ages 1 to 18 years

INTRODUCTION

Many children with musculoskeletal disorders are at high risk of fracture, and the lateral distal femur (LDF) may be the only feasible site to measure bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA). Pediatric reference ranges and adjustment for linear growth are needed to interpret BMD results.

METHODS

Lateral distal femur scans by DXA were obtained on children, ages 1 to 18 y, from two clinical centers. Precision in young children was estimated from duplicate scans. Smoothed reference ranges for three regions of the LDF were generated. Prediction equations were developed to account for the effects of short or tall stature on BMD.

RESULTS

We obtained >2400 measurements on 1,245 children and generated reference ranges for three LDF BMD regions. Precision of BMD was similar (% CV of 1.33 to 2.42 %) to estimates reported at other skeletal sites. Modest sex differences were observed, with females having greater BMD than males at older ages. Children identified as Black had greater BMD than children identified as Non-Black. Height-for-age Z-scores were associated with BMD-for-age Z-scores in pre- and peri-pubertal children, and adjustment equations were generated.

CONCLUSIONS

This study fills substantial gaps in pediatric bone health assessment for children with musculoskeletal disorders who are at high-risk of fracture by providing smoothed reference ranges for ages 1 to 18 y and equations to estimate the impact of small body size on BMD-for-age Z-scores.

Clinical practice recommendations for the diagnosis and management of X-linked hypophosphataemia

X-linked hypophosphataemia (XLH) is a rare metabolic bone disorder caused by pathogenic variants in the PHEX gene, which is predominantly expressed in osteoblasts, osteocytes and odontoblasts. XLH is characterized by increased synthesis of the bone-derived phosphaturic hormone fibroblast growth factor 23 (FGF23), which results in renal phosphate wasting with consecutive hypophosphataemia, rickets, osteomalacia, disproportionate short stature, oral manifestations, pseudofractures, craniosynostosis, enthesopathies and osteoarthritis. Patients with XLH should be provided with multidisciplinary care organized by a metabolic bone expert. Historically, these patients were treated with frequent doses of oral phosphate supplements and active vitamin D, which was of limited efficiency and associated with adverse effects. However, the management of XLH has evolved in the past few years owing to the availability of burosumab, a fully humanized monoclonal antibody that neutralizes circulating FGF23. Here, we provide updated clinical practice recommendations for the diagnosis and management of XLH to improve outcomes and quality of life in these patients.

Bone mineral status at diagnosis οf children with hematologic malignancy

Reduced bone mineral density (BMD) has been reported during and after treatment of children with hematologic malignancies. However, little is known about the skeletal status of these patients at diagnosis. The aim of this study was to evaluate the skeletal profile of newly diagnosed pediatric patients with Acute lymphoblastic leukemia (ALL), Hodgkin Lymphoma (HL), and Non-Hodgkin Lymphoma (NHL). A case-control study included 50 children with ALL, 11 with HL, and 10 with NHL and compared them to 108 sex- and age-matched controls. Patients underwent bone metabolism evaluation and dual-energy X-ray absorptiometry (DXA) scan at the time of diagnosis. Seventy-one children were evaluated (43 boys) with a median age of 8.25 years (2.16-17.33 years). Twenty-one with ALL had bone pain (16 with a limp pain) at diagnosis. More than half (59.1%) of the patients were vitamin D sufficient (25-ΟΗ-D > 20 ng/ml). Patients had lower values of serum procollagen type I C-terminal propeptide (PICP), osteocalcin (OC), and tartrate-resistant acid phosphatase (bTRAP5b) (p < 0.001) than controls. A DXA scan was performed in 45 patients. Patients with ALL and Lymphoma had lower values of Lumbar Spine (L1-L4, LS) BMD Z-score (p < 0.001, p < 0.01, respectively) while those with ALL had lower values of Total Body Less Head (ΤBLH) BMD Z-score (p = 0.003) than controls. Skeletal health is adversely affected in pediatric patients with ALL and Lymphoma at diagnosis. These observations support bone health surveillance in cancer patients and timely intervention starting at the time of diagnosis.

Reduced bone density accrual among peripubertal boys with HIV in Zimbabwe

OBJECTIVE

To investigate bone density accrual over 1 year among peripubertal children with HIV (CWH) compared to children without infection (CWOH); and risk factors associated with bone density accrual among CWH.

DESIGN

A prospective cohort study in urban Zimbabwe.

METHODS

CWH on antiretroviral therapy aged 8-16 years, and CWOH, frequency-matched by age were recruited in Zimbabwe. Z -scores for height-adjusted total-body less-head bone mineral content for lean mass (TBLH-BMC LBM ) and size-adjusted lumbar spine bone mineral apparent density (LS-BMAD) were calculated from dual X-ray absorptiometry (DXA) scan measurements. Linear regression compared bone density accrual by HIV status.

RESULTS

Of 609 participants, 492 (80.7%) completed a follow-up visit (50.2% boys, 49.6% CWH). Mean baseline age was 12.5 years. More girl CWH than CWOH were in Tanner stages I/II at baseline. Bone density accrual (Δ) adjusted for age, Tanner stage and baseline DXA Z -score was less in boy CWH than boy CWOH {adjusted mean (95% confidence interval (CI)] ΔLS-BMAD Z -score -0.14 (-0.25 to -0.02) vs. 0.01 (-0.09 to 0.12), P  = 0.020, and ΔTBLH-BMC LBMZ -score -0.19 (-0.33 to -0.04) vs. 0.07 (-0.07 to 0.20), P  = 0.015}, but similar in girls with and without HIV [ΔLS-BMAD Z -score 0.05 (-0.07 to 0.17) vs. -0.01 (-0.09 to 0.07), P  = 0.416, and ΔTBLH-BMC LBMZ -score 0.08 (-0.07 to 0.22) vs. -0.03 (-0.12 to 0.07), P  = 0.295]. Viral load greater than 1000 copies/ml and tenofovir disoproxil fumarate use were associated with less gain in LS-BMAD Z -score among boys, whereas Tanner stage IV and V were associated with greater gains in LS-BMAD and TBLH-BMC LBMZ -scores among CWH.

CONCLUSION

Among boys only, CWH had impaired bone accrual, associated with high viral load and tenofovir use. Bone density gains were greater in later puberty among CWH suggesting potential to correct deficits.

Prevalence and predictors of low bone mineral density in pediatric inflammatory bowel disease

OBJECTIVES

Bone health is at risk in children with inflammatory bowel disease (IBD). This study examined the prevalence and predictors of low bone mineral density (BMD) in a cohort of children and young adults with IBD.

METHODS

This single-center retrospective study included patients with IBD, ages 3.5-22 years, with completed dual x-ray absorptiometry (DXA) scans from 2006 to 2019. Demographic, clinical, and laboratory data were collected. Logistic regression analysis identified predictors associated with low BMD (Z-scores ≤ -2 standard deviations [SDs]) for three outcomes. In an overlapping IBD cohort with available genetic data between 2002 and 2019 (n = 378), genetic risk for diminished bone health was calculated using published polygenic risk scores generated from genome-wide association studies based on DXA or heel ultrasound speed of sound (SOS). Linear regression analysis examined associations of low BMD and genetic risk.

RESULTS

Low BMD prevalence was 7% in our cohort (n = 600) based on spine bone mineral apparent density (BMAD), which best accounts for growth delays. Median (interquartile range [IQR]) spine BMAD Z-score was -0.37 SD (-1.11 to 0.35). Predictors of low BMAD included lower BMI Z-score (odds ratio [OR]: 0.67, p value: 0.02) and decreased height Z-score (OR: 0.6, p value: 0.005). Of those with longitudinal data (n = 118), low BMI (OR: 0.44, p value: <0.001) and steroid use (OR: 3.42, p value: 0.01) were associated with suboptimal bone health (Z-scores ≤ -1SD). In the cohort with genetic data, heel genomic SOS (β [standard error] = 0.17 [0.35], p ≤ 0.01) was associated with BMD.

CONCLUSIONS

Lower BMI should prompt DXA monitoring in pediatric IBD. Genetic predisposition may identify an at-risk subpopulation.

Development of bone mineral density and content in children with cerebral palsy: a retrospective, longitudinal study

OBJECTIVES

The aim of this study was to investigate long-term bone development in children with cerebral palsy (CP) using longitudinal measurements of total body less head bone mineral content (TBLH-BMC) and bone mineral density (TBLH-BMD).

METHODS

A retrospective longitudinal analysis was performed on 109 children with CP who participated in a rehabilitation programme from 2006 to 2018. Dual-energy X-ray absorptiometry (DXA) scans were performed at the beginning of the programme and repeated as clinically indicated. The study used SITAR growth curve analysis and the LMS method within the GAMLSS model to generate developmental trajectories for TBLH-BMC and TBLH-BMD.

RESULTS

The findings suggest that the expected developmental trajectories of TBLH-BMC and TBLH-BMD in children with CP approximately follow the third percentile of healthy children. The median annual increase in bone mineral density was similar between GMFCS I-II and III-V groups at 5.12 and 5.79 %, respectively. Girls with CP reached age at peak velocity (APV) earlier than boys. The intensive exercise programme may have contributed to greater annual bone growth in children with more severe CP.

CONCLUSIONS

Children with CP have bone growth trajectories close to the third percentile of their healthy peers, suggesting that age-adjusted z-scores for TBLH-BMC and BMD remain relatively stable throughout childhood and adolescence. Early and targeted interventions, including improving muscle strength and mobility and optimising nutritional and hormonal status, are essential to promote better bone health and quality of life in children with CP.

The Prevalence of Reduced Bone Mineral Density and the Impact of Specific Auxological Factors and Hormones on Bone Mass in Children with Endocrine Disorders

Background/Objectives: The skeletal system reaches peak bone mass through modeling and remodeling processes, influenced by environmental, dietary, hormonal, and genetic factors. In children with endocrinopathies, disturbances in bone mass and mineralization may correlate with hormonal levels, but conditions like short stature or obesity can confound DXA results. This study aimed to assess the prevalence of decreased bone mineral density (BMD) in children with endocrine disorders and evaluate the impact of auxological and hormonal abnormalities on BMD. Methods: This study analyzed medical records of 148 children (mean age 11.85 ± 3.34 years); 73 girls and 75 boys). Conditions included obesity (22.9%), short stature (47.9%), precocious puberty (10.1%), and other diagnoses. Clinical data included primary diagnosis, height, body weight, pubertal stage, and serum concentrations of calcium, phosphate, alkaline phosphatase, 25OHD, PTH, osteocalcin, Crosslaps, TSH, fT4, IGF-1, IGF-BP3, cortisol, estradiol, testosterone, and bone age. DXA scans were performed at the total body less head (TBLH) and lumbar spine (Spine) projection. Results: Low bone mass (aBMD Z-score ≤ -2) was found in 34.46% at TBLH and 15.54% at the Spine. After height adjustment (HAZ adjustment), the prevalence of low bone mass decreased to 11.4% at TBLH and 4.1% at the Spine. In the short stature group, the normalization of Z-scores for height significantly reduced abnormal results. A positive correlation was found between DXA parameters and age, height standard deviation score (HSDS), BMI SDS, estradiol, testosterone, IGF-1, and IGF-BP3. A negative correlation existed between vitamin D and DXA parameters. Bone turnover markers (osteocalcin and Crosslaps) also negatively affected bone mass. No significant correlations were found with PTH, TSH, fT4, or cortisol. In children with growth retardation, lower aBMDHAZ Z-scores were observed in those with decreased IGF-1. Positive correlations existed between BMI SDS, IGF-1, and adjusted aBMD Z-scores. Conclusions: Children with endocrine disorders, especially those with short stature, are at risk for bone mineralization disorders. Height normalization is crucial for accurate DXA interpretation and avoiding overdiagnosis. Positive influences on bone mass include height, BMI, IGF-1, estradiol, and testosterone, while negative factors include bone turnover markers and low vitamin D.

The Determinants of Bone Health in Children With Autism Spectrum Disorder: A Systematic Narrative Review

Autism spectrum disorder (ASD) is a complex disorder associated with social and communication impairments and repetitive and restrictive behavioural patterns. Children with ASD often present with concurrent conditions, including poor bone health, which affect long-term health. Although there is compelling evidence to suggest that children with ASD have poorer bone traits than typically developing children, the primary factors associated with these differences are unclear. This review will explore the potential role that factors such as physical activity, nutrition (calcium, protein, vitamin C, vitamin D) and lifestyle (sleep, medication) play on bone health in children with ASD. Having a greater understanding of the influencing factors of low BMD and how these might interact in a synergistic manner in ASD children will provide an opportunity to develop targeted interventions to improve bone health aiming to avert attainment of suboptimal peak bone mass which may lead to early onset osteoporosis, fracture and muscle deconditioning in this paediatric population.

TBS as a complementary tool for assessing vertebral fractures and spinal deformity in children and adolescents with osteogenesis imperfecta

This study evaluated trabecular bone score (TBS) for assessing vertebral fractures and spinal deformity in children and adolescents with osteogenesis imperfecta (OI). TBS showed superior performance in identifying vertebral fractures compared to areal bone mineral density (aBMD), especially in patients without densitometric osteoporosis, suggesting its potential for monitoring vertebral fractures and spinal deformity risk.

BACKGROUND

TBS, derived from a textural greyscale analysis of lumbar spine dual-energy X-ray absorptiometry (DXA) images, offers a non-invasive and indirect evaluation of bone microarchitecture. This method potentially enhances the assessment of skeletal phenotypes beyond the scope of aBMD. We aim to explore the utility of TBS in assessing vertebral fractures and spinal deformity in children and adolescents with OI.

METHODS

In this cross-sectional study, 153 children and adolescents with OI were enrolled. DXA was used to measure TBS and aBMD, and their Z-scores were calculated based on reference values for BMD and TBS in normal children and adolescents with the same age and sex. Lateral thoracolumbar films were used to evaluate vertebral fractures and calculate the spine deformity index (SDI). The accuracy of TBS and aBMD for identifying vertebral compression fractures (VCFs) was assessed using area under the curve (AUC).

RESULTS

TBS Z-score was negatively correlated with the age of children with OI (r =  - 0.435, P < 0.001) and was positively correlated to aBMD Z-score at the lumbar spine and femoral neck (both P < 0.01), even after adjusting for confounding factors. TBS Z-score was as effective as lumbar spine aBMD Z-score in discriminating VCFs (AUC, 0.667 vs 0.666, P > 0.05). Notably, in patients without densitometric osteoporosis, TBS Z-score demonstrated superior discriminative power for VCFs compared to lumbar spine aBMD Z-score (AUC, 0.719 vs 0.545, P < 0.05). In this population, only the TBS Z-score (r =  - 0.358, P < 0.05), rather than the lumbar spine aBMD Z-score, was negatively correlated with the SDI.

CONCLUSION

TBS has a close correlation with bone mineral density in children and adolescents with OI. In patients without densitometric osteoporosis, the Z-score of TBS is more effective than that of bone mineral density in assessing VCFs and spinal deformity, highlighting the potential of TBS in evaluating the risk of VCFs and monitoring the progression of spinal deformity.

Independent effect of body fat content on inflammatory biomarkers in children and adolescents: The GENOBOX study

BACKGROUND AND AIMS

To assess the relationship between body composition indicators and inflammatory biomarkers in children and adolescents of the GENOBOX study.

METHODS AND RESULTS

Anthropometry data from 264 subjects from the subsample of Zaragoza (Spain) included: weight, height, waist circumference, body mass index and triponderal index. Body composition was determined by Dual-energy X-ray Absorptiometry (DXA), obtaining visceral adipose tissue, fat mass index and lean mass index. Age and sex specific z-scores were computed. Simple linear regression models were performed with inflammatory biomarkers (hsCRP, IL8, TNF-α, adiponectin, leptin and resistin) as dependent variables, and each of the body composition indices as independent variables. Prepubertal boys had higher IL8 and resistin values and pubertal girls had higher HOMA-IR and leptin values. hsCPR and leptin were associated with fat mass, both in prepubertals and pubertals, independently of lean mass, and regardless of how body composition was measured. All body composition indices were inversely associated with adiponectin, except for fat mass index in pubertals, but none of them were statistically significant.

CONCLUSION

A positive association between hsCRP and leptin with all body fat composition parameters, measured by standard nutritional indicators and DXA, was observed in both sexual stages.

Bone health and bisphosphonate treatment in females with Rett syndrome in a national center

BACKGROUND

Impaired bone health is a common morbidity in Rett syndrome (RTT). We aimed to assess lumbar bone mineral density (BMD) and trabecular bone score (TBS) in females with RTT, and to evaluate the effectiveness of bisphosphonate treatment.

METHODS

This retrospective study included 40 females with RTT, aged 5-22 years, who underwent dual-energy X-ray absorptiometry (DXA) scans during 2019-2024 at a national center for RTT. Data collected included medical treatment, anthropometric measurements, and functional scores.

RESULTS

The median age at the first DXA scan was 10.8 years. The mean L1-4 BMD Z-score was -2.1 ± 1.4, and the mean TBS Z-score was -0.4 ± 1.3. The L1-4 BMD Z-score correlated with height (r = 0.407, p = 0.009), weight (r = 0.551, p < 0.001), BMI (r = 0.644, p < 0.001), and TBS Z-scores (r = 0.594, p = 0.009). Poor L1-4 BMD Z-scores were associated with poor mobility scores (p = 0.05) and valproate treatment (p = 0.016). Nine patients (23%) received zoledronate, for a mean 2 years. The mean age at zoledronate initiation was 9.7 ± 2.3 years. Four completed two DXA scans (pre- and post-treatment); the mean BMD Z-score improved from -2.2 ± 0.9 to -1.4 ± 0.9 after treatment.

CONCLUSIONS

Females with RTT have reduced lumbar BMD, which was associated with anthropometric factors, TBS, mobility, and valproate use. Zoledronate may be effective for some patients.

IMPACT

In a retrospective study of 40 females with Rett syndrome (RTT), low bone mineral density (BMD) correlated with lower anthropometric measurements, impaired mobility, and valproic acid use. The association between BMD and trabecular bone score (TBS) in the context of RTT is a novel finding. Our preliminary data support the effectiveness and safety of zoledronate for treating osteoporosis in patients with RTT. Our findings are important in light of the increasing life expectancy of individuals with RTT, and the consequent need to prioritize bone health in this population.

The association between dietary inflammatory index and bone health in US adolescents: Analysis of the NHANES data

Introduction

Adolescents with a lower peak bone mineral density (BMD) and bone mineral content (BMC) have an elevated risk of osteoporosis in adulthood. The impact of diet on bone health, particularly its role in managing inflammation, which is a key factor in bone health, is gaining wider recognition. Despite evidence that anti-inflammatory diets can enhance bone health, the link between the dietary inflammatory index (DII) and bone health among US adolescents has not been thoroughly investigated. This study aimed to evaluate the correlation between DII score and bone health in this population.

Methods

This cross-sectional study used data from the National Health and Nutrition Examination Survey (NHANES) of US adolescents aged 12-18 years, spanning surveys from 2001 to 2018. The DII was derived from dietary recall data obtained through questionnaire interviews. Bone health was assessed through total body less head (TBLH) BMD and BMC z-scores and lumbar spine bone mineral apparent density for age (BMADa).

Results

The study comprised 8773 adolescents with a mean age of 14.94 ± 1.97 years, 52.2 % were male. Multivariate linear regression analysis revealed a negative correlation between DII and lumbar spine BMADa (β = -0.000003, 95 % confidence interval [CI], -0.000005 to -0.000001; P = 0.001).This significant association remained robust when DII was treated as a categorical variable. Compared with individuals in quartile 1(Q1) DII scores (-3.71 to 1.04), those in Q4 (3.37 to 5.04) had lower BMADa, with a regression coefficient of -0.00002 (95 % CI, -0.00003 to -0.000007, P < 0.001). DII was negatively correlated with TBLH BMC z-scores; however, the difference was not statistically significant. Subgroup analyses showed that DII was associated with lumbar spine BMADa and TBLH BMC z-scores in participants who were male, non-black, with a higher educational level, with a high family income, and underweight to normal weight. We found no significant association between DII and TBLH BMD z-scores.

Conclusion

The findings from this cross-sectional analysis indicate a significant association between the DII and bone health among adolescents in the US, with a notable impact in males and non-black. These insights underscore the importance of adopting dietary patterns to mitigate inflammation and to support optimal bone health and metabolism.

Outpatient Management of Clinical Comorbidities in Children With Cerebral Palsy in Low- and Middle-Income Countries

BACKGROUND

Cerebral palsy (CP) is the most common physical disability of childhood. Its prevalence in low-and middle-income countries (LMICs) is over 3/1000 live births, about double the 1.6/1000 in high income countries (HICs). Multimorbidity is highly prevalent in CP. In LMICs, there are higher rates of prevalence, severity, comorbidities and mortality in children with CP. The evidence base for the recommendations in CP emanates overwhelmingly from studies conducted in HICs. Research conducted in LMICs settings, involving local clinicians, considering local context and investigating local solutions are urgently needed.

METHODS

This scoping review aimed to identify and synthesise current evidence on management of clinical comorbidities in children with CP in LMICs. The Joanna Briggs Institute guidelines were followed for the data extraction and analysis phases. The following questions guided the scoping review: What are the main clinical comorbidities in children with CP? What are the gold standards for diagnosis and treatment of these comorbidities? What options do we have to diagnose and treat these comorbidities in LMICs when gold standards are not available?

RESULTS

A total of 22 188 citations were identified by our search strategy, with 21 380 remaining after the removal of 808 duplicates. After screening titles and abstracts, 1918 citations progressed to full text review. A total of 194 articles met the eligibility criteria and were included in the review. The guiding questions of the review were answered for the following morbidities: respiratory impairments, dysphagia and aspiration, gastroesophageal reflux disease, drooling, obstructive sleep apnea syndrome, malnutrition, constipation, epilepsy, sleep disorders, spasticity, dystonia, pain, hip disorders, scoliosis and osteoporosis.

CONCLUSION

This article highlights the need for interventions adapted to the realities of LMICs. Empowering paediatricians and healthcare professionals in LMICs is crucial for early diagnosis and proactive interventions. Specific guidelines for LMICs can better guide professionals in managing these complex conditions.

Advances in the estimation of body fat percentage using an artificial intelligence 2D-photo method

There is a growing need to evaluate the agreement between the field methods and integrate artificial intelligence (AI) using two-dimensional (2D) photos for enhanced real-world analysis. This study evaluated the agreement between AI-2D photos and the clinical reference method, dual-energy X-ray absorptiometry (DXA) to estimate the body fat percentage (BFP). Other methods were also investigated, including skinfolds, A-mode ultrasound, and bioelectrical impedance analysis (BIA). This cross-sectional study was conducted on 1273 adults of both sexes. The Bland-Altman plots, Lin's Correlation Coefficient of Agreement (CCC), and error analyses were calculated. AI-2D photos demonstrated substantial agreement with DXA presenting the highest agreement (CCC ≥ 0.96) among all the investigated methods. InBody-270 and Omron HBF-514 BIA devices showed moderate agreement (CCC = 0.90 to 0.95) for all participants, age groups >30 years, and body mass index >25 kg/m2. AI-2D photos can be interchangeable with DXA, providing a practical, accessible alternative and an easy-to-use system for BFP estimation.

The Management of Bone Defects in Rett Syndrome

Rett syndrome (RS) is a rare neurodevelopmental disorder primarily caused by mutations in the X-linked methyl-CpG binding protein 2 (MECP2) gene, responsible for encoding MECP2 which plays a pivotal role in regulating gene expression. The neurological and non-neurological manifestations of RS vary widely in severity depending on the specific mutation type. Bone complications, mostly scoliosis but also osteoporosis, hip displacement, and a high rate of fractures, are among the most prevalent non-neurological comorbidities observed in girls with RS. Low bone mineral density (BMD) is primarily due to a slow rate of bone formation due to dysfunctional osteoblast activity. The use of anticonvulsants, immobilization, low physical activity, poor nutrition, and inadequate vitamin D intake all significantly hamper skeletal maturation and the accumulation of bone mass in RS girls, making them more susceptible to fragility fractures. In RS patients, the upper and lower limbs are the most common sites for fractures which are due to both a reduced BMD and a diminished bone size. This review summarizes the knowledge on risk factors for fragility fracture in patients with RS and proposes a potential diagnostic and therapeutic pathway to enhance low BMD and mitigate the risk of fragility fractures. In particular, this review focused on the importance of clinical and instrumental evaluation of bone status as a basis for adequate planning of nutritional, pharmacological, and surgical interventions to be undertaken. Additionally, the management of bone defects in individuals with RS should be customized to meet each person's specific needs, abilities, and general health.

The role of vitamin D metabolism in regulating bone turnover in adolescents with perinatally-acquired HIV in Southern Africa: a cross-sectional study in Zimbabwe and Zambia

Vitamin D dysregulation can occur in people living with HIV, disrupting calcium homeostasis, and bone turnover. We aimed to investigate the potential mechanisms by which vitamin D regulates bone turnover in adolescents living with perinatally-acquired HIV (ALWH) in Southern Africa. A pre-planned secondary analysis was performed of baseline data from the vitamin D for adolescents with HIV to reduce musculoskeletal morbidity and immunopathology trial (PACTR20200989766029) which enrolled ALWH (11-19 yr) taking antiretroviral therapy for ≥6 mo, and recorded socio-demographic, clinical and dietary data. After over-night fasting, vitamin D metabolites (25(OH)D, 1,25(OH)2D, and 24,25(OH)2D), intact parathyroid hormone (PTH), and bone turnover markers (BTMs) (C-terminal telopeptide of type I collagen (CTX) and procollagen type 1 N-terminal propeptide (P1NP)) were measured. Tandem Mass Spectrometry measured vitamin D metabolites, while intact PTH and BTMs were analyzed by electrochemiluminescence immunoassay. Stratified by 25(OH)D (<75 vs ≥75 nmol/L), associations between standardized concentrations (β = standard deviations) of vitamin D metabolites, intact PTH and BTMs were assessed using structural equations modelling (SEM) adjusted for age, sex, and country (Zimbabwe/Zambia). Among the 842 ALWH enrolled, the median dietary calcium intake was 100 mg (IQR: 55-145). The SEM showed PTH was positively associated (β: 0.21; 95% CI, 0.1, 0.32) with 1,25(OH)2D, only when 25(OH)D was <75 vs ≥75 nmol/L (β: 0.23; 95%CI, -0.13, 0.59), with evidence of an interaction (β: -0.11; 95%CI, -0.20, -0.02). A positive relationship between 25(OH)D and 24,25(OH)2D was seen irrespective of 25(OH)D concentration. 24,25(OH)2D was inversely related to BTMs, particularly when 25(OH)D was <75 nmol/L (CTX: β: -0.15; 95% CI, -0.24, -0.06 and P1NP: β: -0.14; 95%CI, -0.22, -0.06). There was interaction between dietary calcium and 25(OH)D on PTH (β: -0.15; 95% CI, -0.22, -0.07) suggesting an interaction between low 25(OH)D and low dietary calcium which increases PTH. In conclusion, associations between 25(OH)D, PTH, 1,25(OH)2D, and BTMs in ALWH appear dependent upon 25(OH)D concentrations <75 nmol/L and calcium intake. A novel, potentially causal pathway between 25(OH)D, 24,25(OH)2D, and BTMs was seen. Findings enhance understanding of vitamin D metabolism in people living with HIV.

Associations between phthalate metabolites and body composition in children aged 8-19 years

This study aimed to determine the relationship between individual and combined phthalate metabolites and body composition in children and adolescents using data from the 2015-2018 National Health and Nutrition Examination Survey. Single-exposure analysis indicated that most phthalate metabolites were negatively correlated with areal bone mineral density (aBMD). Quantile g-computation demonstrated a negative relationship between the mixture of phthalate metabolites and aBMD, which was confirmed by the Bayesian kernel machine regression model. Sex-stratified analysis revealed that mono-butyl phthalate (MBP) was negatively correlated with aBMD, and MBP, mono-ethyl phthalate (MEP), and mono-isobutyl phthalate (MiBP) were negatively linked to lean mass in males but not in females. The results did not differ according to developmental stages (childhood vs. adolescence). Our findings indicate that phthalate metabolites may affect the body composition in children and adolescents, particularly aBMD. Certain phthalate metabolites seem to be sex-specific, with males showing higher sensitivity than females.

Mid-Childhood Plasma Concentrations of Per- and Polyfluoroalkyl Substances, Modifiable Lifestyle Factors, and Bone Mineral Density Through Late Adolescence

There is limited research on associations of per- and polyfluoroalkyl substances (PFAS) with areal bone mineral density (aBMD) through adolescence and whether bone-strengthening factors ameliorate effects. In the Project Viva cohort (N = 484; 50% female), we used sex-stratified linear regression and quantile g-computation mixture models to examine associations of mid-childhood (median: 7.8 years; 2007-2010) plasma PFAS concentrations with a dual-energy X-ray absorptiometry total-body aBMD Z-score in early and late adolescence (median: 12.9 and 17.6 years, respectively). We explored stratum-specific estimates by parent/self-reported physical activity and dairy intake. Using linear mixed models, we evaluated associations with aBMD accrual from mid-childhood through late adolescence. Females with higher perfluorooctanoate (PFOA) and perfluorodecanoate (PFDA) had lower early adolescent aBMD Z-score [e.g., β(95%CI)] per doubling PFOA: -0.19(-0.41, 0.03)]. Youth with higher PFOA and PFDA had lower late adolescent aBMD Z-score, but CIs were wide [e.g., PFOA: females, -0.12(-0.40, 0.16); males, -0.10(-0.42, 0.21)]. Mixture models generally corroborated single PFAS results, and in linear mixed models, females with higher PFAS concentrations, and males with higher PFOA, had slower aBMD accrual. Less active males with higher PFOA, PFDA, and the PFAS mixture had lower late adolescent aBMD Z-score. Some PFAS appeared more negatively associated with the aBMD Z-score among those who consumed less dairy, but there was not consistent evidence of effect modification. Exposure to select PFAS may affect bone accrual through adolescence, with possible resilience conferred by greater physical activity and dairy intake.

Updated reference values for BMD and lean mass measured by DXA in Thai children

INTRODUCTION

This study established normative references for total body less head (TBLH) BMD, lumbar spine (L1-L4) BMD, and both total and appendicular lean mass (LM) in Thai children and adolescents (aged 5-18 years) using DXA. This work expands upon 2014 normative data for Thai children, which included L2-L4 BMD, total body BMD (head included), and total LM.

MATERIALS AND METHODS

We reanalyzed total body and lumbar spine DXA scans (Lunar Prodigy Pro, GE Healthcare; enCORE version 7.53) from 174 boys and 193 girls, using upgraded software (enCORE version 17SP2) for TBLH BMD, L1-L4 BMD, and LM analysis. The "enhanced" mode was applied for TBLH BMD and LM. Adjustments for total and appendicular LM were made relative to squared height (m2) to account for body size variability.

RESULTS

Normative data stratified by sex and Tanner stage were generated for TBLH BMD, L1-L4 BMD, and LM indices. Weight and Tanner stage significantly determined BMD and LM. Adolescent girls exhibited higher LSBMD values due to earlier pubertal onset. Boys showed higher LM indices with more rapid gains during growth spurts.

CONCLUSION

This study provides updated normative reference values for BMD (TBLH and L1-L4) and LM (total and appendicular) in Thai children and adolescents, measured via DXA. These references will enhance the assessment of low bone mass and LM deficits in Thai pediatric populations, particularly in those with chronic illnesses.

Associations of ethnicity, skin tone, and genome-wide sequencing with bone mineral density in adolescents

BACKGROUND

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).

METHODS

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.

RESULTS

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.

CONCLUSION

Genetic similarity was robustly associated with BMD, prompting a reevaluation of adolescent BMD reference data to exclude the consideration of race.

IMPACT

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.

Association of per- and polyfluoroalkylated substances/heavy metals and bone health in children and adolescents

Background

Research on the correlation between exposure to per- and polyfluoroalkylated substances (PFASs)/heavy metals and bone health during childhood and adolescence is limited. Considering their role as endocrine disruptors, we examined relationships of six PFASs and three heavy metals with bone mineral density (BMD) in children and adolescents using representative samples from the National Health and Nutrition Examination Survey (NHANES).

Methods

The study included 622 participants aged 12-19. The relationship between single pollutant and lumbar spine and total BMD was studied using linear regression analyses. Additionally, Bayesian Kernel Machine Regression (BKMR) models were applied to assess the joint effects of multiple PFASs and heavy metals exposure on the lumbar spine and total BMD.

Results

Statistically significant differences were noted in the serum concentrations of perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), blood lead (Pb), and blood manganese (Mn) between male and female participants (all p < 0.05). Single-exposure studies have shown that Mn was negatively correlated with lumbar spine BMD and total BMD. Multivariate linear regression models revealed that, in the male group, total bone density decreased as the blood PFOA levels [95% CI = (-0.031, -0.001), p = 0.040] and blood manganese levels [95% CI = (-0.009, -0.002), p = 0.004] increased. Similarly, lumbar spine bone density decreased as the blood manganese levels [95% CI = (-0.011, -0.002), p = 0.009] increased. In the female group, total bone density decreased as the serum PFNA levels [95% CI = (-0.039, 0.000), p = 0.048] increased. As shown in the BKMR model, the joint effects of pollutant mixtures, including Mn, were negatively associated with both the lumbar spine and total BMD. Among the pollutants analyzed, Mn appeared to be the primary contributor to this negative association.

Conclusion

This study suggests that exposure to certain PFASs and heavy metals may be associated with poor bone health. Childhood and adolescence are crucial stages for bone development, and improper exposure to PFASs and heavy metals during these stages could potentially jeopardize future bone health, consequently raising the risk of osteoporosis in adulthood.

Assessing the Muscle-Bone Unit in Girls Exposed to Different Amounts of Impact-Loading Physical Activity-A Cross-Sectional Association Study

BACKGROUND/OBJECTIVES

In children, an association exists between muscle and bone, as well as between physical activity and osteogenesis. Impact loading is a factor in increasing bone accrual during growth. In this work, we explored the muscle-bone association in girls exposed to long-term physical activity at different levels of impact loading.

METHODS

Four groups of girls aged 7-16 were considered. The curricular (C; n = 22) group only had curricular physical activity at school (2 h/w). In addition to curricular physical activity, the girls in the dance (D; n = 21), gymnastics at lower training (GL; n = 14), and gymnastics at higher training (GH; n = 20) groups had 2 h/w, 4 h/w, and 4 h/w < training ≤ 12 h/w additional physical activity, respectively, for at least one year. A visual analysis estimated the respective amounts of impact-loading activity. The bone mineral content (BMC), areal bone mineral density (aBMD), and fat-free soft tissue mass (FFSTM) were assessed with dual-energy X-ray absorptiometry.

RESULTS

The results showed that, after adjusting for several confounders, statistically significant correlations were present between muscle mass and several bone mineral variables. A regression analysis confirmed the correlation in the data, and showed the marginal role of other body composition variables and physical activity for predicting BMC and BMD.

CONCLUSION

Skeletal muscle mass is a major determinant of the BMC and BMD of the TBLH, as well as of the Appendicular level, in girls exposed to different amounts of long-term impact-loading physical activity.

Association Between Vitamin D Insufficiency and Impaired Bone Density Among Adolescents With Perinatally Acquired HIV Infection

Background

Stunting and pubertal delay are common among children growing up with human immunodeficiency virus (HIV) and are associated with bone and muscle impairments. We investigated factors associated with bone density and muscle function in adolescents living with HIV (ALWH).

Methods

The VITALITY trial (PACTR202009897660297) investigated whether vitamin D and calcium supplementation improves musculoskeletal health among ALWH. A total of 842 ALWH aged 11-19 years, established on antiretroviral therapy (ART) for ≥6 months, were enrolled from HIV clinics in Zambia and Zimbabwe. Clinical history and examination were undertaken, and serum 25-hydroxyvitamin D3 (25[OH]D3) was measured. Dual-energy X-ray absorptiometry measured total-body-less-head bone mineral density adjusted for height (TBLH-BMDHT), and lumbar spine bone mineral apparent density (LS-BMAD) z scores. The association between a priori-defined covariates and musculoskeletal outcomes were investigated using baseline enrollment data and multivariable logistic regression.

Results

TBLH-BMDHT  z scores were impaired (mean, -1.42 for male and -0.63 female participants), as were LS-BMAD z scores (mean -1.15 for male and -0.47 for female participants). In bivariate analysis, early pubertal stage, less physical activity, and older age at ART initiation were associated with lower TBLH-BMDHT  z scores. Younger age, early pubertal stage, and low socioeconomic status were associated with lower LS-BMAD z scores. Grip-strength-for-height and jump-power-for-height z scores were associated with lower TBLH-BMDHT and LS-BMAD z scores. Low dietary vitamin D and calcium were associated with lower adjusted TBLH-BMDHT  z scores. Lower 25(OH)D3 was associated with lower adjusted TBLH-BMDHT and LS-BMAD z scores.

Conclusions

Deficits in bone density are common in ALWH. Vitamin D and calcium supplementation and promotion of exercise may improve musculoskeletal health among perinatally infected ALWH.

The assessment of bone health in children with juvenile idiopathic arthritis; comparison of different imaging-based methods

BACKGROUND

Osteoporosis is increasingly being recognized in children, mostly secondary to systemic underlying conditions or medication. However, no imaging modality currently provides a full evaluation of bone health in children. We compared DXA, a radiographic bone health index (BHI (BoneXpert) and cone-beam CT for the assessment of low bone mass in children with juvenile idiopathic arthritis (JIA).

METHODS

Data used in the present study was drawn from a large multicentre study including 228 children aged 4-16 years, examined between 2015 and 2020. All had a radiograph of the left hand, a DXA scan and a cone-beam CT of the temporomandibular joints within four weeks of each other. For the present study, we included 120 subjects, selected based on DXA BMD and BoneXpert BHI to secure values across the whole range to be tested.

RESULTS

One hundred and twenty children (60.0% females) were included, mean age 11.6 years (SD 3.1 years). There was a strong correlation between the absolute values of BHI and BMD for both total body less head (TBLH) (r = 0.75, p < 0.001) and lumbar spine (L1-L4) (r = 0.77, p < 0.001). The correlation between BHI standard deviation score (SDS) and BMD TBLH Z-scores was weak (r = 0.34) but significant (0 = 0.001), varying from weak (r = 0.31) to moderate (r = 0.42) between the three study sites. Categorizing BHI SDS and DXA BMD Z-scores on a 0-5 scale yielded a weak agreement between the two for both TBLH and LS, with w-kappa of 0.2, increasing to 0.3 when using quadratic weights. The agreement was notably higher for one of the three study sites as compared to the two others, particularly for spine assessment, yielding a moderate kappa value of 0.4 - 0.5. For cone-beam CT, based on a 1-3 scale, 59 out of 94 left TMJ's were scored as 1 and 31 as score 2 by the first observer vs. 87 and 7 by the second observer yielding a poor agreement (kappa 0.1).

CONCLUSIONS

Categorizing DXA LS and automated radiographic Z-scores on a 0-5 scale gave a weak to moderate agreement between the two methods, indicating that a hand radiograph might provide an adjuvant tool to DXA when assessing bone health children with JIA, given thorough calibration is performed.

Osteoporosis and Bone Fragility in Children: Diagnostic and Treatment Strategies

The incidence of osteoporosis in children is increasing because of the increased survival rate of children with chronic diseases and the increased use of bone-damaging drugs. As childhood bone fragility has several etiologies, its management requires a thorough evaluation of all potentially contributing pathogenetic mechanisms. This review focuses on the main causes of primary and secondary osteoporosis and on the benefits and limits of the different radiological methods currently used in clinical practice for the study of bone quality. The therapeutic and preventive strategies currently available and the most novel diagnostic and treatment strategies are also presented. Optimal management of underlying systemic conditions is key for the treatment of bone fragility in childhood. DXA still represents the gold standard for the radiologic evaluation of bone health in children, although other imaging techniques such as computed tomography and ultrasound evaluations, as well as REMS, are increasingly studied and used. Bisphosphonate therapy is the gold standard for pharmacological treatment in both primary and secondary pediatric osteoporosis. Evidence and experience are building up relative to the use of monoclonal antibodies such as denosumab in cases of poor response to bisphosphonates in specific conditions such as osteogenesis imperfecta, juvenile Paget's disease and in some cases of secondary osteoporosis. Lifestyle interventions including adequate nutrition with adequate calcium and vitamin D intake, as well as physical activity, are recommended for prevention.

Fat-free mass predictive equation using bioelectrical impedance and maturity offset in adolescent athletes: Development and cross-validation

OBJECTIVES

This is a cross-sectional study, aimed to develop and cross-validate a fat-free mass (FFM) predictive equation using single-frequency bioelectrical impedance (BIA), considering the predicted age at peak height velocity (PHV) as a variable. Additionally, the study aims to test the FFM-BIA obtained using a previous predictive equation that used skeletal maturity as a variable.

METHOD

The participants (n = 169 male adolescent athletes) were randomly divided into two groups: development of a new predictive equation (n = 113), and cross-validation (n = 56). The concordance test between the FFM values obtained by Koury et al. predictive equation and DXA data was determined (n = 169). Bioelectrical data was obtained using a single-frequency analyzer.

RESULTS

Among the models tested, the new predictive equation has resistance index (height2/resistance) and predictive age at PHV as variables and presented R2 = 0.918. The frequency of maturity status using skeletal maturity and PHV diagnosis was inadequate (Kappa = 0.4257; 95%CI = 0.298-0.553). Bland-Altman plots and concordance correlation coefficient showed substantial concordance between the FFM-DXA values (48.8 ± 11.2 kg) and the new predictive equation (CCC = 0.960). The results showed that the new equation performed better than the equation developed by Koury et al. (CCC = 0.901).

CONCLUSIONS

Our results show that it is feasible to predict FFM in male adolescent athletes using predictive age at PHV, with moderate concordance. The calculation of FFM using more economical and less complex variables is viable and should be further explored.

Prenatal and childhood exposure to bisphenols and bone mineral density in 7-year-old children from the Odense Child Cohort

BACKGROUND

Bisphenol A (BPA) is a well-known endocrine disrupter used in several consumer products. Restricted use of BPA has led to increased use of bisphenol F (BPF) and bisphenol S (BPS). While previous studies found no associations between prenatal BPA and BPF exposure and bone mineral density (BMD), two recent cohort studies found that prenatal BPS exposure was negatively associated with bone mineral density in the offspring.

AIM

To determine possible associations between maternal and child urinary bisphenol concentrations, BMD and bone mineral content (BMC) in 7-year-old healthy children.

METHODS

Pregnant women were recruited in 2010-2012 to participate in the Odense Child Cohort (OCC), Denmark. Maternal urine samples were collected in gestational week 28 and urinary BPA concentration was measured by isotope diluted LC-MS/MS. The children delivered a urine sample at age 7 years in which BPA, BPF and BPS were measured by an extended LS-MS/MS method based on the original method. At age 7 years DXA scans were performed and BMC and Z-score for BMD calculated. Associations between osmolality adjusted urinary maternal BPA and child BPA, BPF and BPS concentrations and BMC and BMD Z-score were examined by multiple linear regression analysis adjusted for potential confounders. Additionally, a combined effect of the bisphenols were evaluated by including the sum of child urinary BPA, BPF and BPS concentrations in the statistical analyses.

RESULTS

A total of 546 mothers and 453 children aged 7 years participated. BPA was detected in 84% and 96% of the maternal and child urine samples, respectively. We found no significant association between maternal urinary BPA concentration during pregnancy and BMC and BMD Z-score in 7-year-old children. In addition, no association between current bisphenol exposure in tertiles and bone density was found, interestingly, current BPA and summed bisphenol exposure in the highest 10% was associated with lower BMD Z-score at age 7-years, statistically significant for boys.

CONCLUSION

In these low exposed children we found no association between prenatal or current bisphenol exposure in tertiles and BMD in healthy children, however, the highest 10% exposed children had lower BMD, significant for boys, suggesting a negative impact with high bisphenol exposure. The short half-lives of bisphenols and the cross-sectional nature of the child exposure prompt more longitudinal studies to further clarify this topic.

Per- and polyfluoroalkyl substances and bone mineral content in early adolescence: Modification by diet and physical activity

BACKGROUND

Per- and polyfluoroalkyl substance (PFAS) exposures may negatively impact bone mineral accrual, but little is known about potential mitigators of this relation. We assessed whether associations of PFAS and their mixture with bone mineral content (BMC) in adolescence were modified by diet and physical activity.

METHODS

We included 197 adolescents enrolled in a prospective pregnancy and birth cohort in Cincinnati, Ohio (2003-2006). At age 12 years, we collected serum for PFAS measurements and used dual-energy x-ray absorptiometry to measure BMC. We calculated dietary calcium intake and Health Eating Index (HEI) scores from repeated 24-h dietary recalls, physical activity scores using the Physical Activity Questionnaire for Older Children (PAQ-C), and average moderate to vigorous physical activity (MVPA) based on accelerometry. We estimated covariate-adjusted differences in BMC z-scores per interquartile range (IQR) increase of individual PFAS concentrations using linear regression and per simultaneous IQR increase in all four PFAS using g-computation. We evaluated effect measure modification (EMM) using interaction terms between each modifier and PFAS.

RESULTS

Higher serum perfluorooctanoic acid, perfluorooctanesulfonic acid, and perfluorononanoic acid concentrations and the PFAS mixture were associated with lower BMC z-scores. An IQR increase in all PFAS was associated with a 0.27 (-0.54, 0.01) lower distal radius BMC z-score. Associations with lower BMC were generally stronger among adolescents classified as < median for calcium intake, HEI scores, or MVPA compared to those ≥ median. The difference in distal radius BMC z-score per IQR increase in all PFAS was -0.38 (-0.72, -0.04) for those with

CONCLUSION

Healthy, calcium-rich diets and higher intensity physical activity may mitigate the adverse impact of PFAS on adolescent bone health.

Collapse

Key Words

• Adolescent health
• Bone mineral content
• Calcium
• Diet
• Perfluoroalkyl substances
• Physical activity

Collapse

MESH Headings

• Humans
• Female
• Fluorocarbons/blood
• Male
• Bone Density/drug effects
• Child
• Adolescent
• Diet
• Environmental Pollutants/blood
• Prospective Studies
• Ohio
• Alkanesulfonic Acids/blood
• Exercise
• Motor Activity/drug effects

Collapse

Grants

• R01 ES030078 NIEHS NIH HHS
• R01 ES033252 NIEHS NIH HHS
• R01 ES027224 NIEHS NIH HHS
• L40 ES032257 NIEHS NIH HHS
• P01 ES011261 NIEHS NIH HHS
• R01 ES032836 NIEHS NIH HHS
• R01 ES028277 NIEHS NIH HHS
• T32 ES007141 NIEHS NIH HHS
• R01 ES025214 NIEHS NIH HHS
• R01 ES020349 NIEHS NIH HHS

Collapse

Affiliation(s)

Jessie P Buckley Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Junyi Zhou Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
Katherine M Marquess Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
Bruce P Lanphear Faculty of Health Sciences, Simon Fraser University, Vancouver, Canada
Kim M Cecil Department of Radiology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, USA; Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, USA
Aimin Chen Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania Perelman School of Medicine, Philadelphia, USA
Clara G Sears Christina Lee Brown Envirome Institute, Department of Medicine, Division of Environmental Medicine, University of Louisville, KY, USA
Yingying Xu Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, USA
Kimberly Yolton Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, USA
Heidi J Kalkwarf Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, USA
Joseph M Braun Department of Epidemiology, Brown University, Providence, USA
Jordan R Kuiper Department of Environmental and Occupational Health, The George Washington University Milken Institute School of Public Health, Washington, D.C., USA

Collapse

Collaborators Collapse

Muscle-bone cross-talk through the FNIP1-TFEB-IGF2 axis is associated with bone metabolism in human and mouse

Clinical evidence indicates a close association between muscle dysfunction and bone loss; however, the underlying mechanisms remain unclear. Here, we report that muscle dysfunction-related bone loss in humans with limb-girdle muscular dystrophy is associated with decreased expression of folliculin-interacting protein 1 (FNIP1) in muscle tissue. Supporting this finding, murine gain- and loss-of-function genetic models demonstrated that muscle-specific ablation of FNIP1 caused decreased bone mass, increased osteoclastic activity, and mechanical impairment that could be rescued by myofiber-specific expression of FNIP1. Myofiber-specific FNIP1 deficiency stimulated expression of nuclear translocation of transcription factor EB, thereby activating transcription of insulin-like growth factor 2 (Igf2) at a conserved promoter-binding site and subsequent IGF2 secretion. Muscle-derived IGF2 stimulated osteoclastogenesis through IGF2 receptor signaling. AAV9-mediated overexpression of IGF2 was sufficient to decrease bone volume and impair bone mechanical properties in mice. Further, we found that serum IGF2 concentration was negatively correlated with bone health in humans in the context of osteoporosis. Our findings elucidate a muscle-bone cross-talk mechanism bridging the gap between muscle dysfunction and bone loss. This cross-talk represents a potential target to treat musculoskeletal diseases and osteoporosis.

Neuroendocrine disturbances in women with functional hypothalamic amenorrhea: an update and future directions

Functional hypothalamic amenorrhea (FHA) is one of the most common causes of both primary and secondary amenorrhea in women of reproductive age. It is characterized by chronic anovulation and the absence of menses that appear as a result of stressors such as eating disorders, excessive exercise, or psychological distress. FHA is presumed to be a functional disruption in the pulsatile secretion of hypothalamic gonadotropin-releasing hormone, which in turn impairs the release of gonadotropin. Hypoestrogenism is observed due to the absence of ovarian follicle recruitment. Numerous neurotransmitters have been identified which play an important role in the regulation of the hypothalamic-pituitary-ovarian axis and of which the impairment would contribute to developing FHA. In this review we summarize the most recent advances in the identification of contributing neuroendocrine disturbances and relevant contributors to the development of FHA.

Clinical, biochemical, and molecular insights into Cerebrotendinous Xanthomatosis: A nationwide study of 100 Turkish individuals

OBJECTIVE

Cerebrotendinous xanthomatosis (CTX) is an inherited metabolic disorder characterized by progressive neurologic and extraneurologic findings. The aim of this retrospective, descriptive study was to explore the time of presentation and diagnosis, and to expand the phenotype and genotype of CTX, based on a nationwide and comprehensive series of patients in Turkey.

METHODS

The demographic, clinical, biochemical and genotypic characteristics of the CTX patients were reviewed. Data on molecular analysis, age of onset and diagnosis, diagnostic delay, neurologic and extraneurologic symptomatology, results of plasma cholestanol levels, brain magnetic resonance imaging and electromyography at the time of diagnosis were reviewed.

RESULTS

100 confirmed CTX patients from 72 families were included. The mean age at diagnosis was 28.16 ± 14.28 years, and diagnostic delay was 18.39 ± 13.71 years. 36 patients were diagnosed in childhood. Frequency of intention tremor (p = 0.069), peripheral neuropathy (p = 0.234) and psychiatric manifestations (p = 0.396) did not differ between two groups, demonstrating the high rate in pediatric patients. Three adult patients showed a milder phenotype without neurologic involvement. Seven patients had normal plasma cholestanol levels despite neurological impairment. Sequencing of the CYP27A1 gene revealed 25 different variants, with a novel c.671_672del variant not previously described in literature.

CONCLUSION

Based on the observations of this Turkish CTX cohort, it is emphasized that the true prevalence of CTX is probably underestimated and that it has a wide spectrum of clinical phenotypes even without neurological impairment. In children, abnormal cerebellar findings, peripheral neuropathy and psychiatric findings associated with intellectual disability have been suggested as warning signs to avoid diagnostic delay. In cases of clinical suspicion, molecular analysis is recommended despite normal plasma cholestanol levels, as severe neurologic involvement may occur in CTX patients without elevated cholestanol levels.

Impaired bone mineral density and microarchitecture in female adolescents with IgE-mediated cow's milk allergy

This study compared the bone parameters of adolescents with persistent cow's milk allergy (CMA) with those of healthy adolescents. Adolescents with CMA had compromised bone parameters (lower bone mineral density, impaired trabecular microarchitecture, and lower bone strength). Partial exclusion diet was associated with better bone parameters than total exclusion diet.

BACKGROUND

Persistent immunoglobulin E (IgE)-mediated cow's milk allergy (CMA) may impair bone parameters and increase the risk of fractures. High-resolution peripheral quantitative computed tomography (HR-pQCT) is a novel methodology that not only assesses trabecular and cortical bone compartments and volumetric density measurements, but also evaluates bone microarchitecture and estimates biomechanical properties through finite element analysis (FEA). Both HR-pQCT and bone strength parameters derived from FEA have shown a strong correlation with fracture risk.

PURPOSE

To assess the bone density, microarchitecture, and bone strength of adolescents with persistent IgE-mediated CMA (IgE-CMA).

METHODS

This was an observational, cross-sectional study with female adolescents with persistent IgE-CMA and healthy control participants matched by female sex and sexual maturation. Bone parameters were assessed by areal bone mineral density (aBMD) through dual-energy X-ray absorptiometry (DXA), bone microarchitecture by HR-pQCT at the radius and tibia, and laboratory markers related to bone metabolism.

RESULTS

The median age of adolescents with persistent IgE-CMA (n = 26) was 13.0 years (interquartile range (IQR) 11.4-14.7) and of healthy control participants (n = 28) was 13.6 years (IQR 11.9-14.9). Adolescents with IgE-CMA ingested 27.4% less calcium (p = 0.012) and 28.8% less phosphorus (p = 0.009) than controls. Adolescents with IgE-CMA had lower bone mineral content (BMC) (38.83 g vs. 44.50 g) and aBMD (0.796 g/cm2 vs. 0.872 g/cm2) at lumbar spine, and lower BMC (1.11 kg vs. 1.27 kg) and aBMD (0.823 g/cm2 vs. 0.877 g/cm2) at total body less head (TBLH) (p < 0.05). However, Z-scores BMC and Z-scores aBMD at lumbar spine and TBLH, when adjusted for Z-score height/age, were not significantly different between the groups. Moreover, CMA adolescents had lower bone strength at the distal tibia (S 169 kN/mm vs. 194 kN/mm; F Load 8030 N vs. 9223 N) (p < 0.05). Pairing of groups by the presence of menarche showed compromised parameters at the tibia-lower total volumetric BMD (Tt.vBMD) (293.9 mg HA/cm3 vs. 325.9 mg HA/cm3) and trabecular vBMD (Tb.vBMD) (170.8 mg HA/cm3 vs. 192.2 mg HA/cm3), along with lower cortical thickness (Ct.th) (1.02 mm vs. 1.16 mm) and bone strength (S 174 kN vs. 210 kN; F Load 8301 N vs. 9950 N)-and at the radius (S 61 kN/mm vs. 71 kN/mm; F Load 2920 N vs. 3398 N) (p < 0.05) among adolescents with IgE-CMA. Adolescents with IgE-CMA on a total exclusion diet (n = 12) showed greater impairment of bone features than those on a partial exclusion diet (n = 14), with lower lumbar spine Z-score BMC (- 0.65 vs. 0.18; p = 0.013), lumbar spine trabecular bone score (TBS) (1.268 vs. 1.383; p = 0.005), Z-score TBS (0.03 vs. 1.14; p = 0.020), TBLH Z-score BMC (- 1.17 vs. - 0.35; p = 0.012), TBLH Z-score aBMD (- 1.13 vs. - 0.33; p = 0.027), Tt.vBMD at the tibia (259.0 mg HA/cm3 vs. 298.7 mg HA/cm3; p = 0.021), Ct.th at the tibia (0.77 mm vs. 1.04 mm; p = 0.015) and Ct.th at the radius (0.16 mm vs. 0.56 mm; p = 0.033).

CONCLUSION

Adolescents with persistent IgE-CMA had lower aBMD and compromised microarchitecture (impaired trabecular microarchitecture and lower bone strength). Adolescents on a partial exclusion diet had better bone parameters than those on a total exclusion diet.

Assessment and management of low bone mineral density in children with cerebral palsy

Cerebral palsy (CP) is an impairment in motor function and coordination due to a nonprogressive brain injury that occurs pre-, peri-, or postnatally until 2 years of age with a prevalence of 1 to 4 per 1,000 live births. Along with impaired motor function, decreased bone mineral density (BMD) in children with CP is of concern for providers. An algorithm has been created to help identify patients at risk for decreased BMD who are seen by providers. Factors included in the algorithm are medication history, fracture history, ketogenic diet, ambulation status, history of endocrinopathy, and pubertal stage.BMD levels are measured using dual-energy x-ray absorptiometry scans. Once a patient is identified as having decreased BMD several treatment options are available. BMD can be increased through stander use, diet, and bisphosphonate treatment. This paper serves as a summary of the current ways in which children with CP are assessed at each visit, as well as how to treat low BMD once it has been identified.

Key Concepts

(1)Explain the algorithm used to identify patients at risk for decreased BMD.(2)Review how to assess patients with decreased BMD.(3)Summarize treatment recommendations to increase BMD in children with CP.

GBA1 as a risk gene for osteoporosis in the specific populations and its role in the development of Gaucher disease

BACKGROUND

Osteoporosis and its primary complication, fragility fractures, contribute to substantial global morbidity and mortality. Gaucher disease (GD) is caused by glucocerebrosidase (GBA1) deficiency, leading to skeletal complications. This study aimed to investigate the impact of the GBA1 gene on osteoporosis progression in GD patients and the specific populations.

METHODS

We selected 8115 patients with osteoporosis (T-score ≤ - 2.5) and 55,942 healthy individuals (T-score > - 1) from a clinical database (N = 95,223). Monocytes from GD patients were evaluated in relation to endoplasmic reticulum (ER) stress, inflammasome activation, and osteoclastogenesis. An in vitro model of GD patient's cells treated with adeno-associated virus 9 (AAV9)-GBA1 to assess GBA1 enzyme activity, chitotriosidase activity, ER stress, and osteoclast differentiation. Longitudinal dual-energy X-ray absorptiometry (DXA) data tracking bone density in patients with Gaucher disease (GD) undergoing enzyme replacement therapy (ERT) over an extended period.

RESULTS

The GBA1 gene variant rs11264345 was significantly associated [P < 0.002, Odds Ratio (OR) = 1.06] with an increased risk of bone disease. Upregulation of Calnexin, NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) and Apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC) was positively associated with osteoclastogenesis in patients with GD. In vitro AAV9-GBA1 treatment of GD patient cells led to enhanced GBA1 enzyme activity, reduced chitotriosidase activity, diminished ER stress, and decreased osteoclast differentiation. Long-term bone density data suggests that initiating ERT earlier in GD leads to greater improvements in bone density.

CONCLUSIONS

Elevated ER stress and inflammasome activation are indicative of osteoporosis development, suggesting the need for clinical monitoring of patients with GD. Furthermore, disease-associated variant in the GBA1 gene may constitute a risk factor predisposing specific populations to osteoporosis.

Reference-Class Problems Are Real: Health-Adjusted Reference Classes and Low Bone Mineral Density

Elselijn Kingma argues that Christopher Boorse's biostatistical theory (the BST) does not show how the reference classes it uses are objective and naturalistic. Recently, philosophers of medicine have attempted to rebut Kingma's concerns. I argue that these rebuttals are theoretically unconvincing, and that there are clear examples of physicians adjusting their reference classes according to their prior knowledge of health and disease. I focus on the use of age-adjusted reference classes to diagnose low bone mineral density in children. In addition to using the BST's age, sex, and species, physicians also choose to use other factors to define reference classes, such as pubertal status, bone age, body size, and muscle mass. I show that physicians calibrate the reference classes they use according to their prior knowledge of health and disease. Reference classes are also chosen for pragmatic reasons, such as to predict fragility fractures.

Exposure to perfluoroalkyl substances and longitudinal changes in bone mineral density in adolescents and young adults: A multi-cohort study

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) may impair bone development in adolescence, which impacts life-long bone health. No previous studies have examined prospective associations of individual PFAS and their mixture with bone mineral density (BMD) changes in Hispanic young persons, a population at high risk of osteoporosis in adulthood.

OBJECTIVES

To examine associations of individual PFAS and PFAS mixtures with longitudinal changes in BMD in an adolescent Hispanic cohort and examine generalizability of findings in a mixed-ethnicity young adult cohort (58.4% Hispanic).

METHODS

Overweight/obese adolescents from the Study of Latino Adolescents at Risk of Type 2 Diabetes (SOLAR; n = 304; mean follow-up = 1.4 years) and young adults from the Southern California Children's Health Study (CHS; n = 137; mean follow-up = 4.1 years) were included in this study. Plasma PFAS were measured at baseline and dual x-ray absorptiometry scans were performed at baseline and follow-up to measure BMD. We estimated longitudinal associations between BMD and five PFAS via separate covariate-adjusted linear mixed effects models, and between BMD and the PFAS mixture via quantile g-computation.

RESULTS

In SOLAR adolescents, baseline plasma perfluorooctanesulfonic acid (PFOS) was associated with longitudinal changes in BMD. Each doubling of PFOS was associated with an average -0.003 g/cm2 difference in change in trunk BMD per year over follow-up (95% CI: -0.005, -0.0002). Associations with PFOS persisted in CHS young adults, where each doubling of plasma PFOS was associated with an average -0.032 g/cm2 difference in total BMD at baseline (95% CI -0.062, -0.003), though longitudinal associations were non-significant. We did not find associations of other PFAS with BMD; associations of the PFAS mixture with BMD outcomes were primarily negative though non-significant.

DISCUSSION

PFOS exposure was associated with lower BMD in adolescence and young adulthood, important periods for bone development, which may have implications on future bone health and risk of osteoporosis in adulthood.

Assessment of Biochemical Bone Turnover Markers in Polish Healthy Children and Adolescents

BACKGROUND

Assessing bone turnover in paediatric populations is crucial for understanding the physiological changes occurring during skeletal development and identifying potential abnormalities. The objective of this study was to assess osteocalcin (OC), bone alkaline phosphatase (BALP), and C-terminal telopeptide of type I collagen (CTX-I) levels reflecting bone formation and resorption for age and sex in Polish healthy children and adolescents.

MATERIALS AND METHODS

A total of 355 healthy normal-weight children and adolescents (46.5% girls) aged 1-18 years old were recruited. Total body less head (TBLH) and spine L1-L4 were used in children to assess bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA). Bone marker concentrations were determined by immunoenzymatic methods.

RESULTS

Bone marker levels in girls and boys started with higher values in the first year of life and subsequently decreased until reaching a nadir during the prepubertal period. The pubertal peak values of bone markers were reached at 11-13 years old in boys and at 9-11 years old in girls. After puberty, the adolescents showed a gradual decline in bone marker concentrations to the values observed in adults. We found positive correlations between OC level and TBLH-BMD (r = 0.329, p = 0.002), TBLH-BMD Z-score (r = 0.245, p = 0.023), and L1-L4 BMD (r = 0.280, p = 0.009) in the prepubertal group.

CONCLUSIONS

We showed serum levels of bone turnover markers-BALP, OC, and CTX-I-in relation to age and sex in healthy Polish children and adolescents. The age intervals of these markers for girls and boys aged 1-18 years old may be clinically useful in the assessment of bone metabolism in individuals with skeletal disorders.

ESPEN-ESPGHAN-ECFS guideline on nutrition care for cystic fibrosis

BACKGROUND

Nutritional status is paramount in Cystic Fibrosis (CF) and is directly correlated with morbidity and mortality. The first ESPEN-ESPGHAN-ECFS guidelines on nutrition care for infants, children, and adults with CF were published in 2016. An update to these guidelines is presented.

METHODS

The study was developed by an international multidisciplinary working group in accordance with officially accepted standards. Literature since 2016 was reviewed, PICO questions were discussed and the GRADE system was utilized. Statements were discussed and submitted for on-line voting by the Working Group and by all ESPEN members.

RESULTS

The Working Group updated the nutritional guidelines including assessment and management at all ages. Supplementation of vitamins and pancreatic enzymes remains largely the same. There are expanded chapters on pregnancy, CF-related liver disease, and CF-related diabetes, bone disease, nutritional and mineral supplements, and probiotics. There are new chapters on nutrition with highly effective modulator therapies and nutrition after organ transplantation.

Research hotspots for pediatric fractures from 2017 to 2022: A bibliometric and visual analysis via Citespace

Objective

This review provides guidance and ideas for researchers through a comprehensive and comparative analysis of the present state, trends, and hotspots in the pediatric fracture literature over the past 6 years.

Methods

We used Citespace 6.1.R6 software to explore the country/region distribution, institutions, journals, keyword analysis, and co-cited references of the literature from Web of Science core database.

Results

There are 6472 pieces of pediatric fracture-related literature, including 2962 from 2017 to 2019 and 3510 from 2020 to 2022. The country with the most papers is the United States, and US institutions and journals also have a pivotal position in this field. Research hotspots for pediatric fractures in 2017-2019: The topic with the most attention is bone mineral density leading to related bone diseases. Treatment for pediatric fractures, including supracondylar humeral fractures, Monteggia fractures, forearm fractures, knee fractures, and ankle fractures in children, is another topic of greater interest. Brain injuries and dental injuries in children due to abuse and trauma are also concerning issues. Research hotspots for pediatric fractures in 2020-2022: comparison with 2017-2019 revealed a relative decrease regarding ankle-related epiphyseal injuries, but there is a higher focus on the epidemiology of fractures in children, risk factors, and reasons for childhood trauma. We have confirmed through literature co-citations that the literature of high interest is also in these aspects.

Conclusion

Researchers and clinicians can quickly learn about topics of interest through authoritative journals and highly cited literature and rapidly master the current status and frontiers of the field through study, providing ideas for future work.

Bone Mineral Density and Vitamin D Status in Patients with Autoimmune Polyglandular Syndromes: A Single Tertiary Care Center Experience

Immunological abnormalities, the resulting endocrinopathies, and their treatments may impact bone health and 25-hydroxyvitamin D (25-OHD) in patients with autoimmune polyglandular syndromes (APS). Several etiologies contribute to increased risk for low bone mineral density (BMD), including vitamin D deficiency. This study evaluated the vitamin D level and BMD of patients with APS. We performed a cross-sectional study on 44 patients with APS and 55 age and gender-matched control subjects. Among patients with APS, 14 were classified as APS-2 [Addison's disease (AD)+autoimmune thyroid disease (ATD) and/or type 1 diabetes(T1D)]. In contrast, the other 30 were APS-3 (ATD+T1D+other autoimmune diseases). Serum samples were analyzed for vitamin D levels. The lumbar spine and femoral neck BMD were measured by dual X-ray absorptiometry. Z-scores were obtained by comparison with age- and gender-matched average values (both patients and controls). The accepted normal levels were Z-score>-1 and 25-OHD>30 ng/ml. Patients with APS showed 25-OHD levels and BMD significantly lower than healthy controls (p<0.001 and p<0.05, respectively). The highest prevalence of abnormal BMD was observed in the APS-2 subgroup (13 out of 14 patients, 92.6%). Identifying and treating vitamin D deficiency and low BMD is critical in APS patients. The fact that the significant endocrine component of APS-2 is AD, and these patients receive chronic long-term glucocorticoid therapy can be shown as the reason for this result. However, more extensive prospective controlled studies are needed to confirm these findings.

The Relationship between Bone Health Parameters, Vitamin D and Iron Status, and Dietary Calcium Intake in Young Males

Vitamin D, calcium, and iron are micronutrients crucial for bone health. However, their effect has been studied primarily in the cortical bone, with vitamin D status being assessed mainly from the total 25(OH)D serum fraction. The study aimed to investigate the impact of vitamin D (total and free fraction) and iron status (i.e., serum ferritin or soluble transferrin receptor) and calcium intake (ADOS-Ca questionnaire) on lumbar cortical and trabecular bone. In a cohort of 113 male subjects (76 athletes, 37 non-athletes) aged 15-19, the lumbar spine status (Z-score, bone mineral apparent density (BMAD), and trabecular bone score (TBS)) was determined using dual-energy X-ray absorptiometry (DXA). Relationships between the examined micronutrients and bone health parameters were observed only in athletes. Free 25(OH)D was significantly (p < 0.001) correlated with Z-score and BMAD, while total 25(OH)D (p < 0.001) and iron status (ferritin, Fe stores; p < 0.01) correlated solely with BMAD. Free 25(OH)D and ferritin concentrations were the best determinants of bone status (R2 = 0.330; p < 0.001) and explained 25% and 7% of the BMAD variance, respectively. No relationships were found between the micronutrients and TBS. The results confirmed the positive influence of vitamin D and iron on cortical, but not trabecular, bone status solely in physically active subjects. In athletes, free 25(OH)D seems to be a superior indicator of bone health to a total 25(OH)D fraction.

Effects of Hormone Replacement Therapy on Bone Mineral Density in Korean Adults With Turner Syndrome

BACKGROUND

Turner syndrome (TS) is a common chromosomal abnormality, which is caused by loss of all or part of one X chromosome. Hormone replacement therapy in TS is important in terms of puberty, growth and prevention of osteoporosis however, such a study has never been conducted in Korea. Therefore, the purpose of our study was to determine relationship between the starting age, duration of estrogen replacement therapy (ERT) in TS and develop a hormone replacement protocol suitable for the situation in Korea.

METHODS

This is retrospective study analyzed the medical records in TS patients treated at the Severance hospital, Yonsei University College of Medicine, Seoul, Korea from 1997 to 2019. Total of 188 subjects who had received a bone density test at least once were included in the study. Korean National Health and Nutrition Examination Survey (KNHANES) was used for achieving bone mineral density (BMD) of normal control group. Student's t-test, Mann-Whitney U test, ANOVA and correlation analysis were performed using SPSS 18.0.

RESULTS

Each BMD measurement was significantly lower in women with TS than in healthy Korean women. Early start and longer duration of ERT is associated with higher lumbar spine BMD but not femur neck BMD. Femur neck BMD, but not lumbar spine BMD was significantly higher in women with mosaicism than 45XO group.

CONCLUSION

Early onset and appropriate duration of hormone replacement therapy is important for increasing bone mineral density in patients with Turner syndrome. Also, ERT affects differently to TS patients according to mosaicism.

Which indices of cardiorespiratory fitness are more strongly associated with brain health in children with overweight/obesity?

PURPOSE

To compare the strength of associations between different indices of cardiorespiratory fitness (CRF) and brain health outcomes in children with overweight/obesity.

METHODS

Participants were 100 children aged 8-11 years. CRF was assessed using treadmill exercise test (peak oxygen uptake [V̇O2peak ], treadmill time, and V̇O2 at ventilatory threshold) and 20-metre shuttle run test (20mSRT, laps, running speed, estimated V̇O2peak using the equations by Léger et al., Mahar et al., and Matsuzaka et al.). Intelligence, executive functions, and academic performance were assessed using validated methods. Total gray matter and hippocampal volumes were assessed using structural MRI.

RESULTS

V̇O2peak /body mass (β = 0.18, 95% CI = 0.01-0.35) and treadmill time (β = 0.18-0.21, 95% CI = 0.01-0.39) were positively associated with gray matter volume. 20mSRT laps were positively associated with executive functions (β = 0.255, 95% CI = 0.089-0.421) and academic performance (β = 0.199-0.255, 95% CI = 0.006-0.421), and the running speed was positively associated with executive functions (β = 0.203, 95% CI = 0.039-0.367). Estimated V̇O2peak/Léger et al. was positively associated with intelligence, executive functions, academic performance, and gray matter volume (β = 0.205-0.282, 95% CI = 0.013-0.500). Estimated V̇O2peak/Mahar et al. and V̇O2peak/Matsuzaka et al. (speed) were positively associated with executive functions (β = 0.204-0.256, 95% CI = 0.031-0.436).

CONCLUSION

Although V̇O2peak is considered the gold standard indicator of CRF in children, peak performance (laps or running speed) and estimated V̇O2peak/Léger et al. derived from 20mSRT had stronger and more consistent associations with brain health outcomes than other indices of CRF in children with overweight/obesity.

Dual x-ray absorptiometry monitoring in pediatric short bowel syndrome: an integrative review

OBJECTIVE

To analyze the bone health of pediatric patients with short bowel syndrome intestinal failure (SBS-IF).

DATA SOURCE

An integrative literature review was performed using the data published in the MEDLINE-PubMed and Scientific Electronic Library Online (SciELO) databases between January 2010 and April 2021, and through a manual search of the reference lists of relevant studies. Studies were included if they assessed bone mineral density by the Dual X-Ray Absorptiometry (DXA) technique, incorporated pediatric patients (up to 20 years of age) with SBS under parenteral nutrition (PN) and were written in English. Eleven primary sources met the inclusion criteria for this study.

DATA SYNTHESIS

Pediatric patients with SBS-IF under long-term parenteral nutrition experienced frequent changes in bone metabolism, leading to osteoporotic fractures and growth failure. These patients have deficiencies in multiple nutrients, such as calcium, magnesium, phosphorus, and vitamin D. Consequently, there are variations in the secretion and regulation of the parathyroid hormone. In addition, the pharmacotechnical limitations related to calcium and phosphorus in the PN solution, use of glucocorticoids, and difficulty performing physical activity are risk factors for the development of metabolic bone disease in pediatric patients with SBS-IF.

CONCLUSIONS

Low bone mineral density was associated with a high risk of developing osteoporosis, fractures, and growth deficiency in pediatric patients with SBS-IF on PN therapy in the long term.

Evaluation of bone mineral density in adolescent idiopathic scoliosis using a three-dimensional finite element model: a retrospective study

BACKGROUND

Adolescent idiopathic scoliosis (AIS) is often accompanied by osteopenia and osteoporosis, which can cause serious complications. The aim of this study was to determine the specific bone mineral density (BMD) of each vertebral body in patients with AIS using biomechanical finite element modeling based on three-dimensional (3D) reconstruction.

METHODS

This retrospective study involved 56 patients with AIS. Computed tomography (CT) and radiography were performed. Spinal vertebrae were segmented from the spinal CT images of patients with AIS to reconstruct 3D vertebral models. The vertebral models were meshed into tetrahedral finite elements to assess the BMD.

RESULTS

The mean main curve Cobb angle was 88.6 ± 36.7°, and the mean kyphosis angle was 36.8 ± 31.5°. The mean BMD of the global spine was 0.83 ± 0.15 g/cm2. The highest BMD was measured on the concave side of the apex (0.98 ± 0.16 g/cm2). Apical vertebral BMD was negatively correlated with age and height (r = - 0.490, p = 0.009 and r =  - 0.478, p = 0.043, respectively). There were no significant differences in BMD values between the concave and convex sides (p > 0.05).

CONCLUSIONS

The 3D finite element modeling of BMD in patients with AIS is a reliable and accurate BMD measurement method. Using this method, the overall BMD of patients with AIS was shown to gradually decrease from the top to the bottom of the spine. Our findings provide valuable insights for surgical planning, choice of screw trajectories, and additional biomechanical analyzes using finite element models in the context of scoliosis.