Decreased bone mineral density in adults born with very low birth weight: a cohort study

Stature and Its Association With Physiological Stress Exposure in a Pediatric Autopsy Sample

INTRODUCTION AND BACKGROUND

Experiencing illnesses or other stressors may disrupt processes of growth and development throughout the different stages of prepubertal development. Stunted stature for age is one potential outcome from such disruption, with both the nature and timing of stressors playing a role in the development of stunting. This study explores whether stress events in utero or during birth, and prepubertal development have an impact on stature, by examining associations between experience of prenatal or birth issues, postnatal stressor exposure by severity, and stature at time-of-death, with the impact of different stress experiences compared.

METHODS

A coronial pediatric dataset of individuals aged 0-20.9 years (280 male, 195 female) who died in the state of New Mexico from years 2011 to 2019 was assessed for presence/absence of stunting associated with physiological stress exposure type whilst controlling for low socioeconomic status (as inferred by housing type) and sex using two multiple logistic regression models for ages < 12, and for ages 12+. Broad postnatal condition categories were then investigated, again controlling for socioeconomic status and sex for these two cohorts. A linear regression model was also used to assess relationships between stunting, physiological stress, low socioeconomic status housing, and age-at-death.

RESULTS AND DISCUSSION

For both groups aged < 12 and 12+, experiencing moderate to severe illness prior to 12 years of age increased the odds of being stunted at death. Only experience of prenatal or birth issues was associated with younger age-at-death, but stunting itself was not, potentially reflecting the prolonged exposure to severe stressors necessary for stunted growth.

Epigenetic signature of very low birth weight in young adult life

BACKGROUND

Globally, one in ten babies is born preterm (<37 weeks), and 1-2% preterm at very low birth weight (VLBW, <1500 g). As adults, they are at increased risk for a plethora of health conditions, e.g., cardiometabolic disease, which may partly be mediated by epigenetic regulation. We compared blood DNA methylation between young adults born at VLBW and controls.

METHODS

157 subjects born at VLBW and 161 controls born at term, from the Helsinki Study of Very Low Birth Weight Adults, were assessed for peripheral venous blood DNA methylation levels at mean age of 22 years. Significant CpG-sites (5'-C-phosphate-G-3') were meta-analyzed against continuous birth weight in four independent cohorts (pooled n = 2235) with cohort mean ages varying from 0 to 31 years.

RESULTS

In the discovery cohort, 66 CpG-sites were differentially methylated between VLBW adults and controls. Top hits were located in HIF3A, EBF4, and an intergenic region nearest to GLI2 (distance 57,533 bp). Five CpG-sites, all in proximity to GLI2, were hypermethylated in VLBW and associated with lower birth weight in the meta-analysis.

CONCLUSION

We identified differentially methylated CpG-sites suggesting an epigenetic signature of preterm birth at VLBW present in adult life.

IMPACT

Being born preterm at very low birth weight has major implications for later health and chronic disease risk factors. The mechanism linking preterm birth to later outcomes remains unknown. Our cohort study of 157 very low birth weight adults and 161 controls found 66 differentially methylated sites at mean age of 22 years. Our findings suggest an epigenetic mark of preterm birth present in adulthood, which opens up opportunities for mechanistic studies.

Analyzing Patterns of Skeletal Indicators of Developmental Stress Through the Double Lens of Ontogeny and the Life Course Approach in a Contemporary Reference Sample

OBJECTIVES

Skeletal indicators of developmental stress are commonly used to assess health, disease, and patterns of morbidity and mortality in past populations. Incorporating information about individual life history, such as adverse life events, allows for a more thorough understanding of their etiology. This paper adopts the double lens of ontogeny and the life course to analyze indicators of developmental stress in relation to known individual pathologies and developmental patterns of the cranium, vertebrae, and long bones.

MATERIAL AND METHODS

Six skeletal indicators were collected on CT scans or virtual skeletal reconstructions of 1033 contemporary deceased male and female individuals aged between 0 and 20 years from New Mexico: cribra orbitalia, porotic hyperostosis, Harris lines, stunting, vertebral neural canal diameters, and bone mineral density. Autopsy reports provided information on age, sex, disease type, and duration. Polychoric and polyserial correlations, boxplots, balloon plots, factor analyses of mixed data, and cluster analyses were used to explore patterns among indicators, ontogeny, sex, and disease.

RESULTS

The presence and prevalence of indicators varied depending on age and disease: Harris lines, stunted growth, and cribra orbitalia were common in younger age groups and in cases of long-term or respiratory illnesses, while porotic hyperostosis was more prevalent in adolescent and young adult males.

DISCUSSION

Skeletal indicators of developmental stress are most likely associated with the timing of adverse life events in relation to the corresponding ontogenetic patterns, developmental sensitivity to stressors, and developmental plasticity/canalization of the different skeletal elements that bear them.

Appendicular Muscle Mass Index as the Most Important Determinant of Bone Mineral Content and Density in Small for Gestational Age Children

Preterm small for gestational age (SGA) children are at increased risk for low bone mineral content later in life; however, data on SGA children born at term are scarce. We included 44 SGA and 57 adequate for gestational age (AGA) children aged 6 to 11 years to compare bone mineral density (BMD) and bone mineral content (BMC) and to identify which anthropometric and biochemical values influence bone mineralization in these children. Fat mass, appendicular skeletal muscle mass index (ASMMI), BMC, and BMD were significantly lower in SGA children than in AGA (P ≤ .005). Appendicular muscle mass index correlated with BMC(TBLH,FN,L1-L4) and BMD(TBLH,FN,L1-L4) in both groups (r2 = 0.7, P < .05). In multivariate analysis, ASMMI was strongly associated with BMC and BMD in both groups. There were no differences in clinical biomarkers, calcium intake, and physical activity between the groups. Achieving adequate muscle mass contributes to adequate bone mineralization and a lower risk for low BMC and BMD in SGA children.

European survey showed wide variations in diagnostic procedures and management strategies for metabolic bone disease of prematurity in 22 countries

AIM

The aim of this study was to evaluate the clinical relevance, diagnostic procedures and treatment strategies for metabolic bone disease in preterm infants across Europe.

METHODS

An e-survey was distributed by email to 545 neonatal units in 38 European countries between July and October 2021. The protocol was based on the Checklist for Reporting Results of Internet E-Surveys.

RESULTS

In total, 76 neonatal units (14%) from 22 European countries (58%) completed the e-survey. In the 12 months prior to the survey, 29% of 76 units reported at least one symptomatic case of fracture associated with metabolic bone disease of prematurity, and 18% of 76 units reported at least one case of craniofacial deformity. Most centres followed local guidelines for diagnosis (77% of 73 units) and treatment (63% of 72 units). Alkaline phosphatase was the blood marker most used for treatment indication (81% of 72 units), and phosphate supplementation was the treatment most used (82% of 71 units).

CONCLUSION

Metabolic bone disease of prematurity remains clinically relevant. Wide variations in diagnostic procedures and management strategies were observed in European neonatal units. Evidence-based consensus guidelines appear urgently needed to reduce the number of symptomatic cases.

Gestational vitamin D and offspring fracture risk: do associations persist into mid adolescence?

BACKGROUND

Previous studies report that maternal vitamin D exposure during pregnancy is associated with offspring later-life bone health. A study in the Vitamin D in Pregnancy (VIP) cohort reported sexually dimorphic effects of maternal 25-hydroxyvitamin-D (25(OH)D) and offspring fracture profiles at 10 years of age. We, therefore, aimed to determine associations between maternal 25(OH)D status and offspring fracture risk at 16 years of age in this cohort.

METHODS

In total, 475 mother-child pairs were recruited to the VIP study in southeastern Australia. Maternal serum samples were obtained at recruitment (<16 weeks' gestation) and/or 28-32 weeks' gestation and analysed for 25(OH)D. Radiologically-confirmed incident fractures in children were ascertained from date of birth (2002-2004) until July 16, 2019. Cox proportional hazard models were used to determine associations between maternal 25(OH)D and childhood fracture risk, and final models included maternal age at recruitment, offspring sex, birth weight, gestation length and season of 25(OH)D sample.

RESULTS

Data were available for 400 children (mean age 16.1 years). There were 122 (30.5%) children who sustained at least one fracture. Higher maternal 25(OH)D (per 10 nmol/L) in early gestation was associated with a decreased fracture risk in boys (HR 0.87; 95% CI: 0.77, 0.99); the pattern was reversed in girls (HR 1.10; 95% CI 1.00, 1.22). At late gestation, higher maternal 25(OH)D was associated with an increased fracture risk in girls (HR 1.14; 95% CI: 1.04, 1.24).

CONCLUSIONS

While our findings must be interpreted within the constraints of our limitations, we report that the contradictory risk profiles observed at early childhood in this cohort remain in adolescence.

Body composition in adults born preterm with very low birth weight

BACKGROUND

Studies on body composition in preterm very low birth weight (VLBW < 1500 g) survivors are inconsistent and trajectories later in life unknown. We assessed body composition and its change from young to mid-adulthood in VLBW adults.

METHODS

We studied 137 VLBW adults and 158 term-born controls from two birth cohorts in Finland and Norway at mean age 36 years. Body composition was assessed by 8-polar bioelectrical impedance. We compared results with dual-energy x-ray absorptiometry measurements at 24 years.

RESULTS

In mid-adulthood, VLBW women and men were shorter than controls. Fat percentage (mean difference in women 1.1%; 95% CI, -1.5% to 3.5%, men 0.8%; -2.0% to 3.6%) and BMI were similar. VLBW women had 2.9 (0.9 to 4.8) kg and VLBW men 5.3 (2.7 to 8.1) kg lower lean body mass than controls, mostly attributable to shorter height. Between young and mid-adulthood, both groups gained fat and lean body mass (p for interaction VLBW x age>0.3).

CONCLUSION

Compared with term-born controls, VLBW adults had similar body fat percentage but lower lean body mass, largely explained by their shorter height. This could contribute to lower insulin sensitivity and muscular fitness previously found in VLBW survivors and predispose to functional limitations with increasing age.

IMPACT

In mid-adulthood, individuals born preterm with very low birth weight had similar body fat percentage but lower lean body mass than those born at term. This was largely explained by their shorter height. First study to report longitudinal assessments of body size and composition from young to mid-adulthood in very low birth weight adults. Lower lean body mass in very low birth weight adults could contribute to lower insulin sensitivity and muscular fitness and lead to earlier functional limitations with increasing age.

[Association between birth conditions and bone mineral density in adults from the 1982 and 1993 birth cohorts in Pelotas, Rio Grande do Sul State, Brazil]

This study assessed the association of birth weight, gestational age, and intrauterine growth with bone mineral density (BMD) at 22 and 30 years of age in the 1982 and 1993 birth cohorts in Pelotas, Rio Grande do Sul State, Brazil. BMD was measured by dual-energy X-ray absorptiometry (DXA) and the association was assessed using analysis of variance. Multiple linear regression was used to control for confounding factors: sex; household income at birth; maternal smoking during pregnancy; maternal schooling; maternal ethnicity/skin color; and pre-pregnancy body mass index. The study tested whether body fat in adulthood was a mediator of the association analyzed, using the G-computation Formula. A total of 6,803 participants from the 1982 and 1993 cohorts were evaluated at 30 and 22 years of age, respectively. Birth weight was associated with BMD at all sites, with a greater difference at the femoral neck. Individuals born weighing less than 2,000g had on average -0.036g/cm2 (95%CI: -0.064; -0.008) of BMD in the femoral neck than individuals weighing more than 3,500g. Individuals with an intrauterine growth z-score at least 1.28 standard deviation below the mean had an average of -0.013g/cm2 (95%CI: -0.024; -0.002) of BMD in the lumbar spine compared with individuals with an above-average z-score. The mediation analysis showed that body fat in adulthood did not mediate the association. Birth conditions have been associated with BMD in adulthood and the identification of early factors related to bone loss is essential due to the demographic inversion that has been taking place in low- and middle-income countries.

Invited Mini Review Metabolic Bone Disease of Prematurity: Overview and Practice Recommendations

Metabolic bone disease of prematurity (MBDP) is defined by undermineralization of the preterm infant skeleton arising from inadequate prenatal and postnatal calcium (Ca) and phosphate (PO4) accretion. Severe MBDP can be associated with rickets and fractures. Despite advances in neonatal nutrition, MBDP remains prevalent in premature infants due to inadequate mineral accretion ex utero. There also remain significant knowledge gaps regarding best practices for monitoring and treatment of MBDP among neonatologists and pediatric endocrinologists. Preventing and treating MBDP can prevent serious consequences including rickets or pathologic fractures. Postnatal monitoring to facilitate early recognition of MBDP is best done by first-tier laboratory screening by measuring serum Ca, phosphorus, and alkaline phosphatase to identify infants at risk. If these laboratories are abnormal, further studies including assessing parathyroid hormone and/or tubular resorption of PO4 can help differentiate between Ca and PO4 deficiency as primary etiologies to guide appropriate treatment with mineral supplements. Additional research into optimal mineral supplementation for the prevention and treatment of MBDP is needed to improve long-term bone health outcomes and provide a fuller evidence base for future treatment guidelines. Metabolic bone disease of prematurity (MBDP) is defined by undermineralization of the preterm infant skeleton arising from inadequate prenatal and postnatal calcium (Ca) and phosphate (PO4) accretion. Severe MBDP can be associated with rickets and fractures. Despite advances in neonatal nutrition, MBDP remains prevalent in premature infants due to inadequate mineral accretion ex utero. There also remain significant knowledge gaps regarding best practices for monitoring and treatment of MBDP among neonatologists and pediatric endocrinologists. Preventing and treating MBDP can prevent serious consequences including rickets or pathologic fractures. Postnatal monitoring to facilitate early recognition of MBDP is best done by first-tier laboratory screening by measuring serum Ca, phosphorus, and alkaline phosphatase to identify infants at risk. If these laboratories are abnormal, further studies including assessing parathyroid hormone and/or tubular resorption of PO4 can help differentiate between Ca and PO4 deficiency as primary etiologies to guide appropriate treatment with mineral supplements. Additional research into optimal mineral supplementation for the prevention and treatment of MBDP is needed to improve long-term bone health outcomes and provide a fuller evidence base for future treatment guidelines.

Cardiometabolic health in adults born with very low birth weight-a sibling study

BACKGROUND

Preterm survivors have increased risk for impaired cardiometabolic health. We assessed glucose regulation and cardiometabolic biomarkers in adult very low birth weight (VLBW, <1500 g) survivors, using siblings as controls.

METHODS

VLBW-participants were matched with term-born, same-sex siblings. At mean age 29.2 years (SD 3.9), 74 VLBW-adults and 70 siblings underwent a 2-h 75 g oral glucose tolerance test and blood tests for assessment of cardiometabolic biomarkers.

RESULTS

Of participants, 23 (31%) VLBW and 11 (16%) sibling-controls met World Health Organization criteria for impaired glucose regulation (OR adjusted for age and sex 2.5, 95% CI: 1.1 to 5.8). Adjusting for age and sex, VLBW-participants showed 9.2% higher 2-h glucose (95% CI: 0.4% to 18.8%) than their siblings. Also, fasting (13.4%, -0.3% to 29.0%) and 2-h free fatty acids (15.6%, -2.4% to 36.9%) were higher in VLBW-participants. These differences were statistically significant only after further adjusting for confounders. No statistically significant differences were found regarding other measured biomarkers, including insulin resistance, atherogenic lipid profiles or liver tests.

CONCLUSIONS

VLBW-adults showed more impaired fatty acid metabolism and glucose regulation. Differences in cardiometabolic biomarkers were smaller than in previous non-sibling studies. This may partly be explained by shared familial, genetic, or environmental factors.

IMPACT

At young adult age, odds for impaired glucose regulation were 3.4-fold in those born at very low birth weight, compared to same-sex term-born siblings. Taking into consideration possible unmeasured, shared familial confounders, we compared cardiometabolic markers in adults born preterm at very low birth weight with term-born siblings. Prematurity increased risk for impaired glucose regulation, unrelated to current participant characteristics, including body mass index. In contrast to previous studies, differences in insulin resistance were not apparent, suggesting that insulin resistance may partially be explained by factors shared between siblings. Also, common cardiometabolic biomarkers were similar within sibling pairs.

Quantifying Bone Strength Deficits in Young Adults Born Extremely Preterm or Extremely Low Birth Weight

The long-term bone health of young adults born extremely preterm (EP; <28 weeks' gestation) or extremely low birth weight (ELBW; <1000 g birth weight) in the post-surfactant era (since the early 1990s) is unclear. This study investigated their bone structure and estimated bone strength using peripheral quantitative computed tomography (pQCT)-based finite element modeling (pQCT-FEM). Results using this technique have been associated with bone fragility in several clinical settings. Participants comprised 161 EP/ELBW survivors (46.0% male) and 122 contemporaneous term-born (44.3% male), normal birth weight controls born in Victoria, Australia, during 1991-1992. At age 25 years, participants underwent pQCT at 4% and 66% of tibia and radius length, which was analyzed using pQCT-FEM. Groups were compared using linear regression and adjusted for height and weight. An interaction term between group and sex was added to assess group differences between sexes. Parameters measured included compressive stiffness (kcomp ), torsional stiffness (ktorsion ), and bending stiffness (kbend ). EP/ELBW survivors were shorter than the controls, but their weights were similar. Several unadjusted tibial pQCT-FEM parameters were lower in the EP/ELBW group. Height- and weight-adjusted ktorsion at 66% tibia remained lower in EP/ELBW (mean difference [95% confidence interval] -180 [-352, -8] Nm/deg). The evidence for group differences in ktorsion and kbend at 66% tibia was stronger among males than females (pinteractions  <0.05). There was little evidence for group differences in adjusted radial models. Lower height- and weight-adjusted pQCT-FEM measures in EP/ELBW compared with controls suggest a clinically relevant increase in predicted long-term fracture risk in EP/ELBW survivors, particularly males. Future pQCT-FEM studies should utilize the tibial pQCT images because of the greater variability in the radius possibly related to lower measurement precision. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Bone Status and Early Nutrition in Preterm Newborns with and without Intrauterine Growth Restriction

Intrauterine growth restriction (IUGR) together with preterm birth could be harmful to bone health. The aim of the study was to examine bone status in IUGR versus non-IUGR preterms and to analyze the nutritional management best correlated with its improvement. Newborns < 34 weeks of gestational age (wGA), 75 IUGR and 75 non-IUGR, admitted to the Neonatal Intensive Care Unit of the University Hospital of Padova were enrolled and monitored from birth until 36 wGA through anthropometry (weight, length, head circumference, lower limb length (LLL)), biochemistry, bone quantitative ultrasound assessment of bone status (metacarpus bone transmission time, mc-BTT, us) and nutritional intakes monitoring during parenteral nutrition. IUGR compared to non-IUGR showed lower mean mc-BTT (0.45 vs. 0.51, p = 0.0005) and plasmatic phosphate (1.45 vs. 1.79, p < 0.001) at birth. Mc-BTT at 36 wGA, though equal between groups, correlated in IUGR newborns with basal phosphate, mean total energy of the first week and month (positively) and days to reach full enteral feeding (negatively). Lower i.v. vitamin D intake, LLL and prolonged total parenteral nutrition predicted worse mc-BTT at 36 wGA in the enrolled infants. These results suggest that preterms and in particular IUGR newborns need special nutritional care to promote bone development.

Association of Preterm Birth and Low Birthweight with Bone Fractures during Childhood

Preterm birth and low birthweight have been associated with increased fracture risk in children. Our aim was to analyze bone fractures during childhood in preterm, and low-birthweight newborns compared to full-term and normal-birthweight newborns. We conducted a nationwide register-based cohort study in Finland from 1998 to 2017 and utilized the Medical Birth Register and Care Register for Health Care. All newborns alive 28 days after birth were included, and data on all fracture visits in specialized healthcare units were gathered. Incidences per 100,000 person-years with 95% confidence intervals (CI) were calculated, and comparisons were made by incidence rate ratios (IRRs). Kaplan-Meier analysis was used to analyze the timing of fractures during childhood (0-20 years). We included a total of 997,468 newborns and 95,869 fractures; the mean follow-up was 10.0 years, and the overall incidence of fractures was 963 per 100,000 person-years. Very preterm (<32 gestational weeks) newborns had 23% lower fracture incidence than term newborns (IRR 0.77; CI: 0.70-0.85). Preterm newborns (32 to 36 gestational weeks) had a fracture rate (IRR 0.98; CI: 0.95-1.01) similar to that of term newborns. Birthweight showed a linear increase in the fracture rates as newborns with birthweight less than 1000 g had the lowest fracture incidence of 773 per 100,000 person-years and the highest incidence (966 per 100,000 person-years) was among newborns with birthweight 2500 g or more. Children born very preterm or with extremely low birthweight have in general a lower fracture incidence during childhood compared to children born full term and with normal birthweight. These findings possibly reflect, in addition to improvements of neonatal intensive care and early nutrition, the fact that childhood fracture incidences are more dependent on issues other than early life events. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Femur development in fetal growth restriction as observed on prenatal magnetic resonance imaging

OBJECTIVE

To investigate human femur development in fetal growth restriction (FGR) by analyzing femur morphometrics and distal epimetaphyseal features on prenatal magnetic resonance imaging (MRI).

METHODS

This was a retrospective study of 111 fetuses (mean gestational age (GA), 27 + 2 weeks (range, 19-35 weeks)) with FGR associated with placental insufficiency without other major abnormalities and 111 GA-matched normal controls. On 1.5-Tesla echoplanar MRI, femur morphometrics, including diaphyseal length, epiphyseal length and epiphyseal width, were assessed. Using a previously reported grading system, epimetaphyseal features, including cartilaginous epiphyseal shape, metaphyseal shape and epiphyseal ossification, were analyzed qualitatively. To compare FGR cases and controls, the paired t-test was used to assess morphometrics, generalized estimating equations were used for epimetaphyseal features and time-to-event analysis was used to assess the visibility of epiphyseal ossification.

RESULTS

There were significant differences in femur morphometrics between FGR cases and controls (all parameters, P < 0.001), with bone shortening observed in FGR. No significant differences were found in the distribution of epimetaphyseal features between FGR cases and controls (epiphyseal shape, P = 0.341; metaphyseal shape, P = 0.782; epiphyseal ossification, P = 0.85). Epiphyseal ossification was visible at a median of 33.6 weeks in FGR cases and at 32.1 weeks in controls (P = 0.008).

CONCLUSIONS

On prenatal MRI, cases with FGR associated with placental insufficiency exhibit diaphyseal and epiphyseal shortening of the femur. However, FGR cases and normal controls share similarly graded distal epimetaphyseal features. Consequently, these features may not be appropriate MRI characteristics for the identification of FGR. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Both indirect maternal and direct fetal genetic effects reflect the observational relationship between higher birth weight and lower adult bone mass

BACKGROUND

Birth weight is considered not only to undermine future growth, but also to induce lifelong diseases; the aim of this study is to explore the relationship between birth weight and adult bone mass.

METHODS

We performed multivariable regression analyses to assess the association of birth weight with bone parameters measured by dual-energy X-ray absorptiometry (DXA) and by quantitative ultrasound (QUS), independently. We also implemented a systemic Mendelian randomization (MR) analysis to explore the causal association between them with both fetal-specific and maternal-specific instrumental variables.

RESULTS

In the observational analyses, we found that higher birth weight could increase the adult bone area (lumbar spine, β-coefficient= 0.17, P < 2.00 × 10^-16; lateral spine, β-coefficient = 0.02, P = 0.04), decrease bone mineral content-adjusted bone area (BMCadjArea) (lumbar spine, β-coefficient= - 0.01, P = 2.27 × 10^-14; lateral spine, β-coefficient = - 0.05, P = 0.001), and decrease adult bone mineral density (BMD) (lumbar spine, β-coefficient = - 0.04, P = 0.007; lateral spine; β-coefficient = - 0.03, P = 0.02; heel, β-coefficient = - 0.06, P < 2.00 × 10^-16), and we observed that the effect of birth weight on bone size was larger than that on BMC. In MR analyses, the higher fetal-specific genetically determined birth weight was identified to be associated with higher bone area (lumbar spine; β-coefficient = 0.15, P = 1.26 × 10^-6, total hip, β-coefficient = 0.15, P = 0.005; intertrochanteric area, β-coefficient = 0.13, P = 0.0009; trochanter area, β-coefficient = 0.11, P = 0.03) but lower BMD (lumbar spine, β-coefficient = - 0.10, P = 0.01; lateral spine, β-coefficient = - 0.12, P = 0.0003, and heel β-coefficient = - 0.11, P = 3.33 × 10^-13). In addition, we found that the higher maternal-specific genetically determined offspring birth weight was associated with lower offspring adult heel BMD (β-coefficient = - 0.001, P = 0.04).

CONCLUSIONS

The observational analyses suggested that higher birth weight was associated with the increased adult bone area but decreased BMD. By leveraging the genetic instrumental variables with maternal- and fetal-specific effects on birth weight, the observed relationship could be reflected by both the direct fetal and indirect maternal genetic effects.

Multidisciplinary and neuroimaging findings in preterm born very low birthweight individuals from birth to 28 years of age: A systematic review of a Norwegian prospective cohort study

BACKGROUND

Children born preterm with very low birthweight (VLBW) face long-lasting neurodevelopmental challenges, where multidisciplinary assessments are warranted. The International Classification of Functioning, Disability and Health (ICF) provides a framework for understanding and conceptualising these outcomes.

OBJECTIVES

We aimed to review clinical and neuroimaging findings from birth to adulthood in a Norwegian cohort of individuals born preterm with VLBW (gestational age <37 weeks, birthweight ≤1500 g) within the framework of ICF.

DATA SOURCES

We searched PubMed and Embase for articles reporting results of the Norwegian University of Science and Technology (NTNU) Low Birth Weight in a Lifetime Perspective study.

STUDY SELECTION AND DATA EXTRACTION

We included original articles reporting proportions of adverse outcomes, mean group differences, risk factors or associations between outcomes. Data were extracted according to ICF's two-level classification. Body functions and structures comprised outcomes of brain structures, cognition, mental health, vision, pain and physical health. Activities and participation comprised motor skills, general and social functioning, education, employment, and health-related quality of life.

SYNTHESIS

We performed a qualitative synthesis of included articles. Where mean (SD) was reported, we calculated group differences in SD units.

RESULTS

Fifty-eight publications were included. Within body functions and structures, increased prevalence of brain structure pathology, lower cognitive performance, mental health problems, visual and physical health impairments through childhood, adolescence and young adulthood were reported among preterm VLBW participants compared with controls. Within activities and participation, motor problems, lower general and social functioning, and lower academic attainment were found. Perinatal factors were associated with several outcomes, and longitudinal findings suggested persistent consequences of being born preterm with VLBW.

CONCLUSIONS

Being born preterm with VLBW has long-term influences on body functions and structures, activities and participation. The ICF is appropriate for assessing general domains of functioning and guiding the management of individuals born preterm with VLBW.

Bone mineral density in very low birthweight adults-A sibling study

BACKGROUND

Children and adults born very low birthweight (VLBW, <1500 g) at preterm gestations have lower bone mineral density (BMD) and/or bone mineral content (BMC) than those born at term, but causality remains unknown.

OBJECTIVES

Our aim was to assess BMD and BMC in adults born at VLBW in a sibling comparison setting to account for shared genetic and environmental confounders.

METHODS

We conducted a cohort study of 77 adults born VLBW and 70 same-sex term-born siblings at mean age of 29 years. The primary outcome variables were BMD Z-scores, and BMC, of the femoral neck, lumbar spine, and whole body, measured using dual-energy X-ray absorptiometry. We analysed data by linear mixed models.

RESULTS

The VLBW adults had a 0.25 (95% CI 0.02, 0.47) Z-score unit lower femoral neck BMD, and 0.35 (95% CI 0.16, 0.54) grams lower femoral neck BMC than their term-born siblings, after adjustment for sex, age, and maternal smoking. Additional adjustment for adult body size attenuated the results. Lumbar spine, and whole body BMC were also lower in the VLBW group.

CONCLUSIONS

Individuals born at VLBW had lower BMC values at all three measurement sites, as well as lower femoral neck BMD Z-scores, compared to term-born siblings, partly explained by their smaller adult body size, but the differences were smaller than those reported previously with unrelated controls. This suggests that genetic or environmental confounders explain partly, but not exclusively, the association between preterm VLBW birth and adult bone mineralisation.

Outcomes into adulthood of infants born extremely preterm

As survival of infants born extremely preterm increases, more are now reaching adulthood. It is well documented that survivors born extremely preterm experience more developmental delay and disability in multiple domains compared with term-born controls in early childhood and school age. However, with increasing age, health problems involving physical and mental health become more evident. Despite these challenges, it is reassuring that self-reported quality of life remains good. Future directions of research include development of age-appropriate interventions to optimise health and development of individuals born extremely preterm beyond school age.

Maternal vitamin D and offspring fracture risk: the Vitamin D in Pregnancy study

Vitamin D is important for bone health and strength. Previous studies report 25-hydroxyvitamin D (25(OH)D) exposure during pregnancy may impact offspring bone health later in life. In this study, maternal 25(OH)D at recruitment was associated with a lower fracture risk in boys and an increased fracture risk in girls at 28-32 weeks gestation.

PURPOSE

Maternal 25-hydroxyvitamin D (25(OH)D) in pregnancy has been shown to be associated with offspring bone measures in some studies, but few have examined fracture risk. We aimed to determine associations between maternal vitamin D status and offspring fracture risk.

METHODS

In total, 475 mother-child pairs participating in the Vitamin D in Pregnancy study in southeastern Australia were recruited. Maternal serum samples were taken at recruitment (< 16 weeks gestation) and/or 28-32 weeks gestation and analysed for 25(OH)D. Incident fractures in children were ascertained from date of birth (2002-2004) until December 31, 2012. Cox proportional hazard models included maternal age at recruitment, offspring sex, birth weight, gestation length and season of vitamin D sample.

RESULTS

Complete follow-up data were available for 400 children (median age = 9.5 years). There were 68 (17.0%) children who sustained at least one fracture. Higher maternal 25(OH)D (per 10 nmol/L) in early gestation was weakly associated with a decreased fracture risk in boys (HR 0.82; 95% CI 0.68, 0.99; p = 0.048) but not girls (HR 1.10; 95% CI 0.98, 1.25; p = 0.11). At late gestation, higher maternal 25(OH)D was associated with increased fracture risk in girls (HR 1.11; 95% CI 1.01, 1.23; p = 0.038) but not boys (HR 0.94; 95% CI 0.80, 1.10; p = 0.42). No statistically significant relationships were detected in analyses investigating 25(OH)D as a categorical variable.

CONCLUSION

There is some evidence that higher maternal 25(OH)D at recruitment was associated with lower fracture risk in boys, while higher maternal 25(OH)D at 28-32 weeks gestation was associated with an increased fracture risk in girls.

Effects of Self-Regulated Physical Activity in Premature Infants on Bone Density and Length of Stay: A Pilot Study

IMPORTANCE

Premature infants are not prepared developmentally, physically, or cognitively with the multiple survival skills of the typical newborn.

OBJECTIVE

To determine whether physical activity generated spontaneously by premature infants stretching against the resistance of "prepod" garments is as effective as exercises provided by therapists in slowing bone density loss.

DESIGN

Preterm very low birth weight infants were placed in two nonrandomized parallel groups according to birth age.

SETTING

Infants routinely started in a traditional intense intervention setting and graduated to a special care section with private rooms that allowed parents to remain with their child.

PARTICIPANTS

Healthy infants without medical complications, born between 28 and 32 wk postmenstrual age.

INTERVENTION

The control group received traditional exercises. The experimental group wore a prepod almost 24 hr a day. Outcomes and Measures: An ultrasound of the tibia was obtained at 31 to 32 wk and 4 wk later. Weight gain, head circumference growth, and length of stay (LOS) were also measured.

RESULTS

Although not statistically significant, the ultrasound results showed that the prepod group had less loss of bone density than the traditional therapy exercise group. The desired outcome was for pods to be as effective at reducing bone loss as traditional exercise, so the results exceeded expectations. The unexpected, and more notable, finding was a striking drop in LOS for the prepod group.

CONCLUSIONS AND RELEVANCE

Spontaneous exercise by premature infants decreases bone loss and LOS. Better bone health and increased developmental maturity increase the chances of a positive developmental outcome and save the hospital significant expense. What This Article Adds: The prepod is a simple, cost-effective, noninvasive treatment tool occupational therapy practitioners can use to support a premature infant's development. This study has considerable potential to affect how infants are served, both developmentally and financially.

Birth weight is positively associated with adult osteoporosis risk: observational and Mendelian randomization studies

The relationship between birth weight and osteoporosis was inconsistent in previous observational studies. Therefore, we performed a systematic evaluation to determine the inconsistent relationship and further make causal inference based on the UK Biobank datasets (~500,000 individuals) and individual/summary-level genetic datasets. Observational analyses found consistent negative associations either between birth weight and estimated bone mineral density (eBMD) or between genetic risk score (GRS) of birth weight and eBMD in total subjects, and sex-stratified subgroups. Mediation analyses detected significant mediation effects of adult weight and height on associations between birth weight and eBMD. Birth weight was causally associated not only with three BMD phenotypes (eBMD, total body [TB]-BMD, and femoral neck [FN]-BMD) under two effect models (total and fetal effect), but also with the risk of fracture using different Mendelian randomization (MR) methods. Multivariable MR analyses detected the pleiotropic effects of some environmental factors (e.g., gestational duration, head circumference, hip circumference) on the associations between birth weight and BMD/fracture. Three BMD phenotypes (eBMD, TB-BMD, and FN-BMD) have significant mediation effects on the associations between birth weight and fracture by using a novel mediation MR analysis under the multivariable MR framework. This multistage systematic study found consistent causal associations between birth weight and osteoporosis risk, fetal origin of genetic effects underlying the associations, and several mediation factors on the detected associations. The results enhanced our understanding of the effects of fetal original phenotypes on outcomes in late adulthood and provided helpful clues for early prevention research on osteoporosis. © 2021 American Society for Bone and Mineral Research (ASBMR).

Update on Calcium and Phosphorus Requirements of Preterm Infants and Recommendations for Enteral Mineral Intake

Background: With current Ca and P recommendations for enteral nutrition, preterm infants, especially VLBW, fail to achieve a bone mineral content (BMC) equivalent to term infants. During the first 3 years, most notably in light at term equivalent age (<−2 Z score) VLBW infants’ BMC does not catch up. In adults born preterm with VLBW or SGA, lower adult bone mass, lower peak bone mass, and higher frequency of osteopenia/osteoporosis have been found, implying an increased risk for future bone fractures. The aim of the present narrative review was to provide recommendation for enteral mineral intake for improving bone mineral accretion. Methods: Current preterm infant mineral recommendations together with fetal and preterm infant physiology of mineral accretion were reviewed to provide recommendations for improving bone mineral accretion. Results: Current Ca and P recommendations systematically underestimate the needs, especially for Ca. Conclusion: Higher enteral fortifier/formula mineral content or individual supplementation is required. Higher general mineral intake (especially Ca) will most likely improve bone mineralization in preterm infants and possibly the long-term bone health. However, the nephrocalcinosis risk may increase in infants with high Ca absorption. Therefore, individual additional enteral Ca and/or P supplementations are recommended to improve current fortifier/formula mineral intake.

Early Nutrition during Hospitalization in Relation to Bone Health in Preterm Infants at Term Age and Six Months Corrected Age

Aim: to evaluate the potential association of macronutrient intake in the first postnatal weeks on bone mineral content (BMC) and bone mineral density (BMD) in extremely and very preterm infants. Methods: fifty-eight extremely and very preterm infants were included. Daily macronutrient intake was calculated in g kg⁻¹ day⁻¹ from birth up to 36 weeks postmenstrual age. A dual-energy X-ray absorptiometry whole body scan was used to assess BMC and BMD in preterm infants at term corrected age (TCA) and six months corrected age (CA). Results: fat intake (g kg⁻¹ day⁻¹) in the first four postnatal weeks was positively associated with BMC and BMD at TCA. At six months CA, protein and fat intake (g kg⁻¹ day⁻¹) in the first weeks of life were both individual predictors for BMD. Fat intake (g kg⁻¹ day⁻¹) in the first four postnatal weeks was significantly associated with BMC at six months CA. Conclusion: the association of macronutrient intake in the first postnatal weeks on BMC or BMD, at TCA and six months CA, suggest that early nutritional intervention immediately after birth and during early infancy is important for bone health in the first months of life.

Bone Mineral Density, Body Composition, and Metabolic Health of Very Low Birth Weight Infants Fed in Hospital Following Current Macronutrient Recommendations during the First 3 Years of Life

The present study longitudinally evaluated growth, bone mineral density, body composition, and metabolic health outcome in very low birth weight (VLBW) infants whose in-hospital target nutrient intake was within recent recommendations. From six months to three years, bone mineral density (dual-energy X-ray absorptiometry, DXA), body composition, and metabolic health outcome were compared with a reference group of term infants. The aim was to test whether in-hospital achieved weight gain until 36 weeks of gestation (light or appropriate for term equivalent age; LTEA or ATEA) predicts later growth, bone mineral density (BMD), abdominal obesity, or metabolic health outcomes such as insulin resistance, relative to term infants, during the first three years of life. Target in-hospital energy and protein intake was not achieved. Growth in weight, length and head circumference, mid arm circumference, adiposity, fat free mass (FFM), and bone mineralization in VLBW infants was less than those in term infants and influenced by nutritional status at discharge. Preterm infants had poorer motor and cognitive outcomes. Post-discharge body composition patterns indicate FFM proportional to height but lower fat mass index in LTEA preterm infants than term infants, with no evidence of increased truncal fat in preterm infants. The hypothesis of early BMD catch-up in VLBW infants after discharge was not supported by the present data. The clinical significance of these findings is unclear. The data may suggest a reduced obesity risk but an increased osteoporosis risk. Since postnatal growth restriction may have permanent negative health effects, LTEA VLBW infants would especially appear to benefit from targeted preventive interventions. Further follow-up of the infants is required.

Low birth weight and its relation to physical fitness parameters in children: Its negative effect on muscle strength and cardiorespiratory endurance

BACKGROUND

There is increasing evidence that low birth weight has a negative effect on physical fitness, muscle strength, and cardiorespiratory endurance, although the findings are inconsistent.

OBJECTIVES

This study aimed to evaluate whether birth weight acts as a prenatal determinant of physical fitness parameters and to determine the role of environmental or biological variables on this effect.

METHODS

One hundred and sixty-seven children aged 6-14 years were included in this study. The anthropometric data, physical activity index, standing long jump, flexibility, handgrip strength, and cardiorespiratory fitness were evaluated.

RESULTS

A positive correlation was found between birth weight and cardiorespiratory fitness (r = .349; p < .001), right handgrip strength (r = .337; p < .001), and left handgrip strength (r = .320; p < .001), suggesting that children with low birth weight had the worst performance in both cardiorespiratory endurance and grip strength tests. These findings remained significant after adjustment for prematurity, sex, age, physical activity index, and body mass index (BMI). Stepwise multiple regression analyses revealed a significant interaction of high birth weight, older age, and low BMI in predicting better cardiorespiratory endurance (R² = .308). When handgrip strength was tested as the dependent variable, we found that high birth weight, male sex, and older age emerged as important determinants for both sides.

CONCLUSION

Children aged 6-14 years born with a birth weight < 2.5 kg have low handgrip strength and cardiorespiratory fitness, which seems to be mediated partially by influences of both prenatal environment (e.g., birth weight) and biological variables (e.g., age, sex, BMI).

Bone health in young adult survivors born extremely preterm or extremely low birthweight in the post surfactant era

BACKGROUND

Most infants born extremely preterm (EP; <28 weeks' gestation) or extremely low birthweight (ELBW; <1000 g birthweight) in the post surfactant era (early 1990s) are now surviving into adulthood. Preterm birth/low birthweight are risk factors for reduced bone growth and mineralisation in infants and children. However, little is known about their bone health around peak bone mass and through adult life.

OBJECTIVE

To compare bone health (bone mineral measures, bone structure and strength) in young adults born EP/ELBW with controls (>2499 g birthweight), and within the EP/ELBW group examine perinatal and later variables associated with long term bone health.

METHODS

A geographic cohort comprising all 297 survivors born EP/ELBW in 1991-92 in the state of Victoria, Australia, and 260 contemporaneous controls (>2499 g birthweight) were recruited into a longitudinal study from birth. At age 25 years, investigations included dual energy X ray absorptiometry and peripheral quantitative computed tomography to measure bone, muscle and soft tissue variables, and fasting blood samples to measure serum 25 hydroxyvitamin D (25(OH)D) and bone turnover markers (BTM). Linear regression analysis, with models fitted using generalised estimating equations, was used to compare outcomes between groups, adjusting for height and weight.

RESULTS

Compared with controls (n = 129), young adults born EP/ELBW (n = 162) had lower areal bone mineral density (g/cm²) (mean difference [MD] -0.044; 95% confidence interval [CI] -0.076,-0.013) and Z-scores (MD -0.53; 95% CI -0.75, -0.30) in the femoral neck, and lower total hip Z-score (MD -0.35; 95% CI -0.54, -0.15) after adjusting for height and weight. EP/ELBW males generally displayed more bone and soft tissue deficits than females, compared with their respective controls. Within the EP/ELBW group, early growth, male sex, height and lean mass, muscle measures, 25(OH)D levels, and BTM were independently associated with bone mineral measures, structure or strength.

CONCLUSIONS

Young adults born EP/ELBW had evidence of impaired bone health around the age of peak bone mass compared with controls. Further follow-up of the EP/ELBW groups will determine if they have a heightened low-trauma fracture risk in later life.

Predictors of Vertebral Deformity in Long-Term Survivors of Childhood Acute Lymphoblastic Leukemia: The PETALE Study

BACKGROUND

The prevalence of vertebral deformities in long-term survivors of childhood acute lymphoblastic leukemia (ALL) is unknown. Our objectives were to identify the prevalence of vertebral deformities and their risk factors among long-term childhood ALL survivors.

METHODS/RESULTS

We recruited 245 (49% male) long-term childhood ALL survivors from the Preventing Late Adverse Effects of Leukemia Cohort (French-Canadian ALL survivors treated between the years 1987 and 2010 with the Dana Farber Cancer Institute clinical trials protocols, who did not experience disease relapse and/or receive hematopoietic stem cell transplant). Median age at recruitment was 21.7 years (range, 8.5-41) and median time since diagnosis was 15.1 years (range, 5.4-28.2). All participants underwent spine radiograph and dual-energy X-ray absorptiometry scans. The prevalence of vertebral deformity was 23% with 88% classified as grade 1 according to the Genant method. The majority of vertebral deformities were clinically silent. Regression analysis confirmed male sex (risk ratio [RR] = 1.94; 95% confidence interval [CI], 1.16-3.24; P = 0.011), higher glucocorticoid cumulative dose (RR = 1.05; 95% CI, 1.00-1.10; P = 0.032), and back pain (RR = 2.44; 95% CI, 1.56-3.84; P < 0.001) as predictors of prevalent vertebral deformity. Sex differences in vertebral deformity predictors emerged.

CONCLUSIONS

We report a significant prevalence of vertebral deformities in this young cohort. Male sex, cumulative glucocorticoid dose, and back pain were identified as predictors of prevalent vertebral deformity. Back pain emerging as a strong predictor of vertebral deformity underscores the importance of ongoing bone health surveillance in survivors with persistent vertebral deformities treated with these earlier protocols.

Comparison of prevalence and characteristics of fractures in term and preterm infants in the first 3 years of life

BACKGROUND

Preterm infants may be more vulnerable to fractures due to various factors, including metabolic bone disease, but an increased risk of fractures up to the age of 2 is unproven.

OBJECTIVE

To compare fracture patterns in premature and full-term children in the first 3 years of life.

MATERIALS AND METHODS

A retrospective study was conducted. We excluded any child who returned with the same injury, with known metabolic bone disease, with any disease or condition known to reduce bone density, who received any medication known to affect Vitamin D metabolism within 3 months of enrollment or who had fractures post-surgery/resuscitation. Variables such as the number of fractures sustained each year, age of presentation to the Emergency Department and mechanism of injury were compared between the preterm and term groups using statistical analysis (χ² and Fisher exact test for categorical variables and Student's t-test for continuous variables). Simple linear regression was performed on the total number of fractures sustained by age 3.

RESULTS

Forty-four children with fractures were included. Of these, none were born extremely preterm, 24 (55%) were preterm, and 20 (45%) were born at term. Mean gestational ages of the preterm and term groups were 32 weeks 3 days and 39 weeks 6 days, respectively. There were no extremely low birth weight or very low birth weight children. There was no significant difference in the number of fractures sustained yearly, the age of presentation to the Emergency Department or the site of fracture between preterm and term groups. Linear regression showed that the total number of fractures sustained by age 3 years was unrelated to prematurity status, gender or birth weight category.

CONCLUSION

No significant difference in fracture number or pattern was identified.

Bone Mineral Density in Adolescent Boys: Cross-Sectional Observational Study

Physical inactivity of children can be a precursor of reduced bone mineral density, considered to be a typical problem only in old age. The aim of this study was to evaluate bone mineral density in 96 Polish boys aged 14–17 years with varied physical activity (swimmers, track and field athletes, non-athletes) and the effect of bone composition, birth weight and breastfeeding during infancy on bone parameters. Anthropometric and body composition measurements were performed according to the kinanthropometric standards. Bone parameters of the forearm were measured by means of dual-energy X-ray absorptiometry. Data on the infant’s birth weight and the length of breastfeeding were collected during direct interviews with mothers. The strongest links with bone parameters were found for the type of physical activity and birth weight. Regardless of birth weight, track and field athletes had the most advantageous bone parameters (mainly sT-score prox values). Swimmers with normal or low birth weight had less favourable sT-score prox values than non-athletes. The type of physical activity proved to be an important determinant of bone parameters. Childhood and adolescence are important periods of bone development and increasing the content of bone mineral components, and the bone status in later years of life depends to a large extent on this period. The perinatal period, especially the correct birth weight of the child, not only has a significant effect on general health, but also on bone status.

The long-term impacts of preterm birth and associated morbidities on bone health in preschool children: a prospective cross-sectional study from Turkey

Objective: To evaluate the impact of preterm birth on bone health in preschool children.Methods: A total of 166 preschool children (aged 7-8 years) born preterm (n = 86, <37-week gestation) and at term (n = 80, ≥37 weeks of gestation) in our hospital were included in this prospective cross-sectional study. Data on antenatal, perinatal, and early postnatal characteristics and maternal obstetric history were obtained from medical records. Bone densitometry data including total bone mineral content (BMC), bone mineral density (BMD; total, lumbar, and femoral), z-scores, and bone loss were collected for each participant.Results: Current height, weight, and BMI values were significantly lower in the preterm group (p < .001). Serum calcium, phosphorus and alkaline phosphatase (ALP) levels did not differ among groups, whereas VitD3 levels were significantly higher in the preterm group (p = .039). The mean total BMC, total BMD, lumbar (L2-L4) BMD, femur BMD, total z-score, and L2-L4 z-score values were significantly lower for the preterm group, whereas the total, lumbar, and femoral bone loss were significantly higher (p < .001), regardless of the severity of prematurity. Intraventricular hemorrhage (IVH) and retinopathy were significantly associated with lower total BMC (p = .004, p = .012, respectively). Fortified breastfeeding was associated with lumbar bone loss (p = .043), and formula feeding was associated with both femur and lumbar bone loss (p = .006, p = .012, respectively).Conclusions: Our findings revealed long-term adverse effects of preterm birth on bone health, with significantly lower anthropometric values (weight, height, and BMI), lower scores for total BMC, BMD (total, lumbar, femoral), and z-scores (total, femur), along with higher bone loss (total, lumbar, femoral) and higher rates of osteopenia and osteoporosis in preschool children born preterm (whether moderate or very preterm) compared with those born at term. Exclusive breastfeeding appears to reduce the likelihood of long-term bone loss in preterm infants.

Diverging effects of premature birth and bronchopulmonary dysplasia on exercise capacity and physical activity - a case control study

Background

Extreme prematurity has been associated with exercise intolerance and reduced physical activity. We hypothesized that children with bronchopulmonary dysplasia (BPD) would be especially affected based on long-term lung function impairments. Therefore, the objective of this study was to compare exercise capacity and habitual physical activity between children born very and extremely preterm with and without BPD and term-born children.

Methods

Twenty-two school-aged children (aged 8 to 12 years) born with a gestational age < 32 weeks and a birthweight < 1500 g (9 with moderate or severe BPD (=BPD), 13 without BPD (=No-BPD)) and 15 healthy term-born children (=CONTROL) were included in the study. Physical activity was measured by accelerometry, lung function by spirometry and exercise capacity by an incremental cardiopulmonary exercise test.

Results

Peak oxygen uptake was reduced in the BPD-group (83 ± 11%predicted) compared to the No-BPD group (91 ± 8%predicted) and the CONTROL group (94 ± 9%predicted). In a general linear model, variance of peak oxygen uptake was significantly explained by BPD status and height but not by prematurity (p < 0.001).

Compared to CONTROL, all children born preterm spent significantly more time in sedentary behaviour (BPD 478 ± 50 min, No-BPD 450 ± 52 min, CONTROL 398 ± 56 min, p < 0.05) and less time in moderate-to-vigorous-physical activity (BPD 13 ± 8 min, No-BPD 16 ± 8 min, CONTROL 33 ± 16 min, p < 0.001). Prematurity but not BPD contributed significantly to explained variance in a general linear model of sedentary behaviour and likewise moderate-to-vigorous-physical activity (p < 0.05 and p < 0.001 respectively).

Conclusion

In our cohort, BPD but not prematurity was associated with a reduced exercise capacity at school-age. However, prematurity regardless of BPD was related to less engagement in physical activity and more time spent in sedentary behaviour. Thus, our findings suggest diverging effects of prematurity and BPD on exercise capacity and physical activity.

Placental colonization with periodontal pathogens: the potential missing link

Observational studies demonstrate that women with severe periodontitis have a higher risk of adverse pregnancy outcomes like preterm birth and low birthweight. Standard treatment for periodontitis in the form of scaling and root planing during the second trimester failed to reduce the risk of preterm or low birthweight. It is premature to dismiss the association between periodontitis and adverse pregnancy outcomes because one explanation for the failure of scaling and root planing to reduce the risk of adverse pregnancy outcomes is that periodontal pathogens spread to the placental tissue prior to periodontal treatment. In the placenta, orally derived organisms could cause direct tissue damage or mediate a maternal immune response that impairs the growth of the developing fetus. Sequencing studies demonstrate the presence of organisms derived from the oral microbiome in the placenta, but DNA-based sequencing studies should not be the only technique to evaluate the placental microbiome because they may not detect important shifts in the metabolic capability of the microbiome. In humans, polymerase chain reaction and histology have detected periodontal pathogens in placental tissue in association with multiple adverse pregnancy outcomes. We conclude that both placental and oral microbiomes may play a role in periodontitis-associated adverse pregnancy outcomes. However, the measure to determine the association between periodontal pathogens in the placenta and adverse pregnancy outcomes should be the amount and prevalence, not the mere presence of such microorganisms. Placental colonization with periodontal pathogens thus potentially represents the missing link between periodontitis and adverse pregnancy outcomes.

Does height catch-up in schoolchildren have an effect on bone mass in adolescents? Analysis in a Brazilian birth cohort

OBJECTIVE

To analyze the effect of height catch-up at school age on the bone mass of adolescents of a Brazilian birth cohort.

METHODS

A cohort study using data obtained from the three moments (birth, 7/9 years and 18/19 years of age) of the Cohorts-RPS study. Height catch-up was defined based on the difference between the schoolchild's z-score and birth z-score. The adolescents' bone mineral mass was analyzed using the z-score index for the lumbar spine measured by dual emission X-ray absorptiometry. A theoretical model was developed for the proposed analysis using directed acyclic graphs paired through the nearest-neighbor matching propensity score using the STATA software, version 14.0. The level of significance was set at 5%.

RESULTS

Of the 297 studied children, 24.5% achieved height catch-up. The bone mass below the expected for age was observed in 5.39% of the subjects. The mean lumbar spine z-score was -0.34 (±1.01). After the adjustment, no effect was observed between height catch-up at school age and bone mass in adolescents (Coeff=0.598; 95% CI -0.117 to 1.313; p=0.101).

CONCLUSION

Even using the directed acyclic graphs and the causal inference method by adjusting the propensity score, the height catch-up did not seem to affect bone mass in adolescents, a result perhaps related to the sample size.

Metabolic bone disease of prematurity: causes, recognition, prevention, treatment and long-term consequences

Metabolic bone disease of prematurity (MBDP) is characterised by skeletal demineralisation, and in severe cases it can result in fragility fractures of long bones and ribs during routine handling. MBDP arises from prenatal and postnatal factors. Infants who are born preterm are deprived of fetal mineral accumulation, 80% of which occurs in the third trimester. Postnatally, it is difficult to maintain a comparable intake of minerals, and medications, such as corticosteroids and diuretic therapy, lead to bone resorption. With improvements in neonatal care and nutrition, the incidence of MBDP in preterm infants appears to have decreased, although the recent practice of administering phosphate supplements alone will result in secondary hyperparathyroidism and associated bone loss, worsening MBDP. Postnatal immobilisation and loss of placental supply of oestrogen also contribute to skeletal demineralisation. There is no single diagnostic or screening test for MBDP, with pitfalls existing for most radiological and biochemical investigations. By reviewing the pathophysiology of calcium and phosphate homeostasis, one can establish that plasma parathyroid hormone is important in determining the aetiology of MBDP - primarily calcipaenia or phosphopaenia. This will then direct treatment with the appropriate supplements while considering optimal physiological calcium to phosphate ratios.

Developmental Programming of Body Composition: Update on Evidence and Mechanisms

PURPOSE OF REVIEW

A growing body of epidemiological and experimental data indicate that nutritional or environmental stressors during early development can induce long-term adaptations that increase risk of obesity, diabetes, cardiovascular disease, and other chronic conditions-a phenomenon termed "developmental programming." A common phenotype in humans and animal models is altered body composition, with reduced muscle and bone mass, and increased fat mass. In this review, we summarize the recent literature linking prenatal factors to future body composition and explore contributing mechanisms.

RECENT FINDINGS

Many prenatal exposures, including intrauterine growth restriction, extremes of birth weight, maternal obesity, and maternal diabetes, are associated with increased fat mass, reduced muscle mass, and decreased bone density, with effects reported throughout infancy and childhood, and persisting into middle age. Mechanisms and mediators include maternal diet, breastmilk composition, metabolites, appetite regulation, genetic and epigenetic influences, stem cell commitment and function, and mitochondrial metabolism. Differences in body composition are a common phenotype following disruptions to the prenatal environment, and may contribute to developmental programming of obesity and diabetes risk.

Preterm Birth as a Risk Factor for Metabolic Syndrome and Cardiovascular Disease in Adult Life: A Systematic Review and Meta-Analysis

OBJECTIVE

To determine if preterm birth is associated with components of the metabolic syndrome in adult life.

STUDY DESIGN

A structured literature search was performed using PubMed. All comparative studies reported metabolic and cardiovascular outcomes in adults (≥18 years of age) born preterm (<37 weeks of gestation) compared with adults born at term (37-42 weeks of gestation) and published through March 2018 were included. The major outcomes assessed were body mass index, waist circumference, waist-to-hip ratio, fat mass, systolic blood pressure (SBP), diastolic blood pressure (DBP), 24-hour SBP, 24-hour DBP, endothelium-dependent brachial artery flow-mediated dilation, carotid intima-media thickness, pulse wave velocity, fasting glucose and insulin, Homeostasis Model Assessment-Estimated Insulin Resistance Index, and lipid profiles. Quality appraisal was performed using a modified version of the Newcastle-Ottawa scale. A meta-analysis was performed for comparable studies which reported sufficient data.

RESULTS

Forty-three studies were included, including a combined total of 18 295 preterm and 294 063 term-born adults. Prematurity was associated with significantly higher fat mass (P = .03), SBP (P < .0001), DBP (P < .0001), 24-hour SBP (P < .001), and 24-hour DBP (P < .001). Furthermore, preterm-born adults presented higher values of fasting glucose (P = .01), insulin (P = .002), Homeostasis Model Assessment-Estimated Insulin Resistance Index (P = .05), and total cholesterol levels (P = .05) in comparison with adults born at term, in random effect models. No statistically significant difference was found between preterm and term-born adults for the other outcomes studied.

CONCLUSIONS

Preterm birth is strongly associated with a number of components of the metabolic syndrome and cardiovascular disease in adult life.

Active care of infants born between 22 and 26 weeks of gestation does not follow consensus expert recommendations

AIM

To determine the relationship between clinical practice and publication of an Australian consensus statement for management of extremely preterm infants in 2006.

METHODS

A population-based study using linked data from New South Wales, Australia for births between 22 + 0 and 26 + 6 weeks of gestation between 2000 and 2011.

RESULTS

There were 4746 births of whom 2870 were liveborn and 1876 were stillborn. Of the live births, 2041 (71%) were resuscitated, 1914 (67%) were admitted into a neonatal intensive care unit (NICU) and 1310 (46%) survived to hospital discharge. Thirty-nine (2%) stillbirths were resuscitated but none survived. No 22-week infant survived to hospital discharge. Fewer 23-week gestation infants were resuscitated between 2004 (52%) and 2005 (20%) but resuscitation rates increased by 2008 (44%). There was no difference at other gestations. Adjusted odds ratio (OR) for resuscitation was increased by birthweight (OR: 1.01), tertiary hospital birth (OR: 3.4) and Caesarean delivery (OR: 11.3) and decreased by rural residence (OR: 0.4) and male gender (OR: 0.7).

CONCLUSION

Expert recommendations may be shaped by clinical practice rather than the converse, especially for 23-week gestation infants. Recommendations should be revised regularly to include clinical practice changes.

Does type of feeding affect body composition in very low birth weight infants? - A prospective cohort study

BACKGROUND

The aim of the study was to analyse body composition of preterm infants fed with either breast milk or formula compared to a control group of full-term newborns.

METHODS

Fifty-three newborns were enrolled: a group of 34 very low birth weight (VLBW) preterm newborns subdivided into a formula-fed (n = 23; group A) and breast milk-fed (n = 11; group B) group, and a control group of 19 full-term infants (group C). Their body composition was assessed by a bioelectrical impedance analysis (BIA) either at the estimated time of birth in the VLBW group or during the 1st week of life in the full-term group.

RESULTS

There was no difference in body weight or length between any of the three studied groups. However, we discovered that fat free mass (% FFM) was lower (83.5% vs. 85.5%; p < 0.01), while fat mass (% FM) was higher (16.4% vs.14.5%; p < 0.01) in group A compared to full-term newborns. There were no such differences in FFM (84.3% vs. 85.5%; p = 0.13) or FM (15.7% vs. 14.5%; p = 0.13) between group B and control.

CONCLUSION

To sum up, the VLBW infants fed with breast milk shared similar body composition with the full-term infants, while the formula-fed VLBW developed higher amounts of adipose tissue and lower amounts of fat-free mass. This is the first study to expose differences in fat tissue content attributed to type of provided nutrition, which has become significant as early as estimated time of birth despite the comparable weight.

Prematurity Does Not Increase Early Childhood Fracture Risk

OBJECTIVE

To evaluate the impact of prematurity on fracture by age 5, controlling for medications and comorbidities of prematurity.

STUDY DESIGN

We performed a retrospective cohort study of infants born in Military Treatment Facilities in 2009-2010 with ≥5 years of follow-up care. Gestational age, low birth weight, comorbidities of prematurity (osteopenia, necrotizing enterocolitis, chronic lung disease, and cholestasis) and fractures were identified by International Classification of Disease, 9th Edition, codes. Pharmaceutical records identified treatment with caffeine, diuretics, postnatal corticosteroids, and antacids. Poisson regression analysis determined fracture rate by 5 years of life.

RESULTS

There were 65 938 infants born in 2009-2010 who received care in the military health system for ≥5 years, including 3589 born preterm; 165 born at ≤28^6/7 weeks of gestation, 380 born at 29-31^6/7 weeks of gestation, and 3044 born at 32-36^6/7 weeks of gestation. Preterm birth at any gestational age was not associated with fracture rate in adjusted models. The fracture rate was increased with cholestasis, proton pump inhibitor exposure, and male sex.

CONCLUSIONS

Prematurity was not associated with fracture rate. Neonatal cholestasis and proton pump inhibitor treatment were associated with increased fractures by age 5.

Comparison of physical activity and body composition in a cohort of children born extremely preterm or with extremely low birth weight to matched term-born controls: a follow-up study

OBJECTIVES

To compare physical activity and body composition in a cohort of children born extremely preterm/extremely low birth weight (EP/ELBW) with term-born (TB) controls.

METHODS

A regional cohort of children born during 1999-2000 at gestational age <28 weeks or with birth weight <1000 g and their individually matched TB controls were examined in 2010-2011. Information on physical activity was obtained from parental questionnaires, and body composition was determined by anthropometry and dual X-ray absorptiometry.

RESULTS

Fifty-seven EP/ELBW and 57 TB controls were included at a mean age of 11.6 years. Compared with the TB children, the EP/ELBW-born children exercised less often (22% vs 44% exercised more than 3 days per week), had lower physical endurance and poorer proficiency in sports and play and were less vigorous during exercise (p<0.05). They also had lower values (mean; 95 % CI) for muscle mass (0.9; 0.3-1.5 kg), total bone mineral density z-score (0.30; 0.13-0.52 units) and fat mass ratio (0.14; 0.06-0.21 units). The association between physical activity and bone mineral and skeletal muscle mass accrual was significantly weaker for the EP/ELBW-born than the TB children.

CONCLUSIONS

The EP/ELBW-born children were less physically active, had signs of an unfavourable body composition with less muscle mass and lower bone mineral density than the TB controls. The association between physical activity and the measures of body composition was weaker in the group of EP/ELBW-born children.

Early postnatal nutrition after preterm birth and cardiometabolic risk factors in young adulthood

Objectives

Adults born preterm at very low birthweight (VLBW; <1500 g) have a non-optimal cardiometabolic risk factor profile. Since higher protein intake during the first weeks of life predicted a healthier body composition in adulthood in our previous studies, we hypothesized that it would also predict a favorable cardiometabolic profile.

Study design

The Helsinki Study of VLBW Adults includes 166 VLBW and preterm infants born between 1978 and 1985. We collected postnatal nutrition data among 125 unimpaired subjects, who attended two study visits at the mean ages of 22.5 and 25.1 years. We evaluated the effects of energy and macronutrient intakes during the first three 3-week periods of life on key cardiometabolic risk factors with multiple linear regression models. We also report results adjusted for prenatal, postnatal and adult characteristics.

Results

Macronutrient and energy intakes were not associated with blood pressure, heart rate, or lipid levels in adulthood. Intakes were neither associated with fasting glucose or most other markers of glucose metabolism. An exception was that the first-three-weeks-of-life intakes predicted higher fasting insulin levels: 1 g/kg/day higher protein intake by 37.6% (95% CI: 8.0%, 75.2%), and 10 kcal/kg/day higher energy intake by 8.6% (2.6%, 14.9%), when adjusted for sex and age. These early intakes similarly predicted the adult homeostasis model assessment index. Further adjustments strengthened these findings.

Conclusions

Among VLBW infants with relatively low early energy intake, early macronutrient and energy intakes were unrelated to blood pressure, lipid levels and intravenous glucose tolerance test results. Contrary to our hypothesis, a higher macronutrient intake during the first three weeks of life predicted higher fasting insulin concentration in young adulthood.

The long-term impact of very preterm birth on adult bone mineral density

Introduction

Preterm infants are at increased risk of osteopenia of prematurity due to insufficient bone mineral accretion. Data on long term effects of prematurity on bone health are conflicting. This study aimed to compare bone mineral density (BMD) in young adults born very preterm and full-term controls and to examine factors associated with long-term bone health.

Methods

This observational cross-sectional study enrolled 101 young adults (18–29 years) born <29 weeks of gestation and 95 sex- and age-matched full-term controls. Participants underwent dual-energy X-ray absorptiometry to measure areal BMD and body composition. Generalized estimated equations were used to compare groups adjusting for height Z-score, lean body mass and fat mass.

Results

Adults born preterm were shorter and lighter than full-term controls. Areal BMD was reduced at the lumbar spine, the femoral neck and whole body in the preterm versus full-term group, but after adjustment, areal BMD Z-score was only significantly lower at the femoral neck by −0.3 unit (95% confidence interval −0.6 to −0.0). Low BMD (Z-score ≤ −1 standard deviation) at any site was observed in 53% of adults born preterm versus 28% of full-term controls, but this was not statistically significantly different. We did not identify any neonatal factors associated with lower BMD within the preterm group.

Conclusions

Very preterm birth is associated with lower areal BMD at the femoral neck in young adulthood, even after accounting for body size. Whether this will translate into higher risk of osteoporotic fractures later in life remains unknown.

Assessing the genetic correlations between early growth parameters and bone mineral density: A polygenic risk score analysis

OBJECTIVE

The relationships between early growth parameters and bone mineral density (BMD) remain elusive now. In this study, we performed a large scale polygenic risk score (PRS) analysis to evaluate the potential impact of early growth parameters on the variations of BMD.

METHODS

We used 2286 Caucasian subjects as cohort 1 and 3404 Framingham Heart Study (FHS) subjects as cohort 2 in this study. BMD at ulna & radius, hip and spine were measured using dual energy X-ray absorptiometry. BMD values were adjusted for age, sex, height and weight as covariates. Genome-wide single-nucleotide polymorphism (SNP) genotyping of the 2286 Caucasian subjects was performed using Affymetrix Human SNP Array 6.0. The GWAS datasets of early growth parameters were driven from the Early Growth Genetics Consortium, including birth weight (BW), birth head circumference (BHC), childhood body mass index (CBMI), pubertal height growth related indexes and tanner stage. Polygenic Risk Score (PRSice) and linkage disequilibrium (LD) score regression analysis were conducted to assess the genetic correlation between early growth parameters and BMD.

RESULTS

We detected significant genetic correlations in cohort 1, such as total spine BMD vs. CBMI (p value = 1.51 × 10^-4, rg = 0.4525), right ulna and radius BMD vs. CBMI (p value = 1.51 × 10^-4, rg = 0.4399) and total body BMD vs. tanner stage (p value = 7.00 × 10^-4, rg = -0.0721). For cohort 2, significant correlations were observed for total spine BMD vs. height change standard deviation score (SDS) between 8 years and adult (denoted as PGF + PGM) (p value = 3.97 × 10^-4, rg = -0.1425), femoral neck BMD vs. the timing of peak height velocity by looking at the height change SDS between age 14 years and adult (denoted as PTF + PTM) (p value = 7.04 × 10^-4, rg = -0.2185), and total spine BMD vs. PTF + PTM (p value = 6.86 × 10^-4, rg = -0.2180).

CONCLUSION

Our study results suggest that some early growth parameters could affect the variations of BMD.

Effect of foetal and infant growth and body composition on respiratory outcomes in preterm-born children

Body composition and growth outcomes of preterm-born subjects have been studied by many researchers. In general, preterm-born children have lower height and weight especially in infancy. Despite showing potential for catch-up growth, they continue to lag behind their term counterparts in adolescence and adulthood. The various methods of studying body composition and the differing gestations and ages at which it is assessed may go some way to explaining the inconsistent results observed in different studies. In addition, there is a paucity of data on the effects of foetal and infant growth and of body composition on later respiratory outcomes. In largely term-born subjects, foetal growth and growth trajectories appear to have differential effects on later respiratory outcomes. Early weight gain in infancy appears to be associated with increased respiratory symptoms in childhood but catch-up growth in infancy appears to be associated with possible improved lung function status.

Leisure time physical activity in 9- to 11-year-old children born moderately preterm: a cohort study

BACKGROUND

Physical activity is one of the best documented activities with impacts on health in children and adults. Children born preterm show reduced physical and psychosocial function compared to children born at term. This may influence their level of physical activity. Reports on moderately preterm children's physical activities during childhood are limited. Thus, the aim of this study was to compare the leisure time physical activity at age 9-11 years of moderately preterm children with that of children born at term.

METHODS

Data from 4941 mother-child pairs from the Aarhus Birth Cohort (1989-91) were used. The cohort gathered clinical information, including gestational age at delivery. Information about parental socio-demographic and lifestyle factors was obtained from questionnaires completed during the second trimester of pregnancy. Information about children's physical activities was reported in a 9- to 11-year follow-up questionnaire completed by parents detailing how many times per week their child participated in sports activities outside of school, hours spent per week playing outside, and hours per week engaged in sedentary activities. Data were analysed using multiple logistic regression with the lowest activity group as a reference group.

RESULTS

A total of 158 children (3.2%) were born moderately preterm, i.e., between 32 and 36 completed weeks. Children born moderately preterm participated in sports activities as often as their peers born at term; they also participated in frequent sports activities (≥ 4 times per week) as often as their peers. There were no differences in hours per week spent playing outside or in sedentary activities between the two groups.

CONCLUSIONS

Nine- to 11-year-old moderately preterm children participated in sports activities outside school to a similar extent as their peers and engaged in outdoor activities and sedentary activities for the same duration of time per week as their peers born at term.

Somatic development and some indices of lipid metabolism in 11-year-old children born with extremely low birth weight (< 1000 g) (long-term cohort study)

AIM

To continue the prospective follow-up cohort study on the somatic development and lipid metabolic parameters of 11-year-old-children born with extremely low birth weight and to compare them with the results obtained in the study of 7-year-old children from the same group.

MATERIAL AND METHODS

204 newborns with birth weight ≤1000 g were born in the Malopolska voivodship between 1.09.2002 and 31.08.2004. From this group 115 (56%) children died during infancy and 89 (44%) infants survived. At the age of 7 years 81 (91%) of the children from this group were examined. At the age of 11 years investigations were carried out in 62 (75%) of the children, while 19 (26%) were lost to follow-up. All the children underwent anthropometric measurements. Moreover, the lipid profile (serum total cholesterol, triglycerides, HDL-cholesterol, LDL cholesterol) was evaluated. The control group consisted of 36 children born at term chosen randomly from the general population and matched with regard to age and sex.

RESULTS

Children born with extremely low birth weight were generally smaller than their peers. At 7 years, they were shorter (113.75 cm(-0.72) vs.124.52 cm(0.53)), lighter (19.47 kg(-1.12)vs.25.23 kg(0.39)), had a smaller head circumference (49.81 cm(-2.19) vs.52.5 cm(-0.377)), waist circumference (50.14 cm(-0.83) vs.55.45 cm (0.34)), mid-upper arm circumference (17.51 cm vs. 19.29 cm), skinfold thickness (0.76cm(-0.817) vs.0.92cm (-0.19)) and body mass index (14.5 kg/m2 (-0.99)vs.16.16 kg/m2 (0.12)) expressed both as absolute values and z-score values compared to the control group. At 11 years old, the height (141.7 cm(-0.368) vs.146.26 cm(0.65)), weight (33.88 kg (-0.59)vs.40.45 kg(0.66)), head circumference (51.37 cm(-2.05)vs.54.02 cm(-0.33)), waist circumference (61.7 cm (0.26) vs.67.84 cm(1.06)), mid-upper arm circumference (20.95 cm vs. 22.85 cm), skinfold thickness (1.17 cm(-0.25)vs.1.68 cm(0.78)) and body mass index (16.74 kg/m2 (-0.62) vs.18.72 kg/m2 (0.36)) expressed both as absolute values and z-score values were still lower in children born with extremely low birthweight than in the control group. However, their gains over the time period between 7 and 11 years were comparable to their born-at-term peers in all the measured anthropometric parameters. There were no statistically evident differences in the indices of lipid metabolism.

CONCLUSIONS

Preterm children with extremely low birth weight (<1000 g) are at an increased risk of growth failure. Once they reach teenage years they are shorter and lighter than their age- and sexmatched born-at-term peers. They also have smaller heads. In our study we did not find statistically evident differences between the investigated and control group in lipid indices. There is a need for longitudinal studies to observe somatic, mental and metabolic development in order to organize multidisciplinary holistic medical care for them.

Effects of serum 25-hydroxyvitaminD level on decreased bone mineral density at femoral neck and total hip in Chinese type 2 diabetes

OBJECTIVE

The aims of this study is to observe the levels of serum 25-hydroxyvitaminD (25OHD), parathyroid hormone and bone mineral density (BMD) in type 2 diabetes as well as to analyze the correlationship between 25OHD level and BMD.

METHODS

The subjects included 368 type 2 diabetic patients, ages ranged 40-79 years and 300 non-diabetic control subjects matched for age, gender and body mass index. The serum 25OHD concentration, parathyroid hormone level and BMDs value at lumbar spine (L1-L4), femoral neck, total hip and total body were measured. The BMDs (g/cm2) was measured by LUNAR's DEXA dual-energy X-ray absorptiometry.

RESULTS

①Compared with control subjects, the serum 25OHD level, BMDs at the femoral neck and total hip declined in type 2 diabetes[(45±17 vs. 36±12 nmol/L), (0.93±0.17 vs. 0.85±0.14 g/cm2), (0.93±0.14 vs. 0.87±0.15g/cm2) (all P<0.05)]; The parathyroid hormone level in type 2 diabetes was higher in type 2 diabetes than that in control subjects (8.5±4.2 vs. 5.6±3.9 pmol/L) (P<0.05). ②Compared with diabetes duration ≤10 years group, BMDs at the femoral neck and total hip decreased in diabetes duration >10years group [(0.88±0.11 vs. 0.81±0.15 g/cm2), (0.91±0.14 vs. 0.84±0.16 g/cm2)(All P<0.05)]; The parathyroid hormone level increased in diabetes duration >10years group than diabetes duration ≤10 years group (10.6±9.1 vs. 7.1±3.7 pmol/L) (P<0.05). ③ Compared with hemoglobin A1c (HbA1c) ≤8% group, 25OHD and BMDs at the femoral neck and total hip in HbA1c>8% group decreased [(40±15 vs. 32±13 nmol/l), (0.89±0.13 vs. 0.83±0.13 g/cm2), (0.95±0.13 vs. 0.83±0.16 g/cm2) (All P<0.05)] and the parathyroid hormone level increased (7.2±4.0 vs. 10.0±8.8 pmol/L) (P<0.05). ④The morbidity of diabetic osteoporosis and osteopenia (41.0%, 47.8%) were higher than those in control subjects (27.0%,33.3%) (X2 = 4.37 and 4.70, P = 0.04 and 0.03); Diabetes duration, HbA1c and parathyroid hormone levels were longer or higher in Diabetic osteoporosis group than those in normal BMD group and osteopenia group(All p<0.05). ⑤ Simple factor correlation analysis showed that the BMD at the femoral neck was negatively correlated with the age, diabetes duration, HbA1c, parathyroid hormone (rs = -0.18,-0.23,-0.18,-0.25), and positively correlated with 25OHD (rs = 0.23).

CONCLUSIONS

Decreased BMDs and increased incidence of osteoporosis were observed in type 2 diabetic patients, which are closely related to the serum 25OHD level. These findings were more prominent at the femoral neck and total hip for patients with a longer diabetic history and poor glycemic control.

Neonatal Nutrition Predicts Energy Balance in Young Adults Born Preterm at Very Low Birth Weight

Epidemiological studies and animal models suggest that early postnatal nutrition and growth can influence adult health. However, few human studies have objective recordings of early nutrient intake. We studied whether nutrient intake and growth during the first 9 weeks after preterm birth with very low birth weight (VLBW, <1500 g) predict total energy intake, resting energy expenditure (REE), physical activity and food preferences in young adulthood. We collected daily nutritional intakes and weights during the initial hospital stay from hospital records for 127 unimpaired VLBW participants. At an average age 22.5 years, they completed a three-day food record and a physical activity questionnaire and underwent measurements of body composition (dual X-ray absorptiometry; n = 115 with adequate data) and REE (n = 92 with adequate data). We used linear regression and path analysis to investigate associations between neonatal nutrient intake and adult outcomes. Higher energy, protein and fat intakes during the first three weeks of life predicted lower relative (=per unit lean body mass) energy intake and relative REE in adulthood, independent of other pre- and neonatal factors. In path analysis, total effects of early nutrition and growth on relative energy intake were mostly explained by direct effects of early life nutrition. A path mediated by early growth reached statistical significance only for protein intake. There were no associations of neonatal intakes with physical activity or food preferences in adulthood. As a conclusion, higher intake of energy and nutrients during first three weeks of life of VLBW infants predicts energy balance after 20 years. This association is partly mediated through postnatal growth.