Tracking of size-adjusted bone mineral content and bone area in boys and girls from 10 to 17 years of age

Female rats consuming an iron and omega-3 fatty acid deficient diet preconception require combined iron and omega-3 fatty acid supplementation for the prevention of bone impairments in offspring

We previously showed in rats that pre- and postnatal deficiencies in iron and omega-3 (n-3) fatty acids can impair bone development, with additive and potentially irreversible effects when combined. This study aimed to investigate, in female rats consuming a combined iron and n-3 fatty acid deficient (ID + n-3 FAD) diet preconception, whether supplementation with iron and docosahexaenoic/eicosapentaenoic acid (DHA/EPA), alone and in combination, can prevent bone impairments in offspring. Using a 2 × 2 factorial design, female Wistar rats consuming an ID + n-3 FAD diet preconception were randomised to receive an: 1) iron supplemented (Fe + n-3 FAD), 2) DHA/EPA supplemented (ID + DHA/EPA), 3) Fe + DHA/EPA, or 4) ID + n-3 FAD diet from gestational day 10 throughout pregnancy and lactation. Post-weaning, offspring (n = 24/group; male:female = 1:1) remained on the respective experimental diets for three weeks until postnatal day 42-45. Offspring born to female rats consuming a control diet preconception and an Fe+DHA/EPA diet throughout pregnancy and lactation served as non-deficient reference group (Control+Fe+DHA/EPA). Bone mineral density (BMD) was measured using dual-energy X-ray absorptiometry and bone strength using three-point bending tests. Only offspring in the Fe+DHA/EPA group had significantly higher spine and femur BMD, and higher femur stiffness than offspring in the ID + n-3 FAD group, and had similar spine BMD and femur stiffness as the Control + Fe + DHA/EPA group. Offspring in the Fe + DHA/EPA group further had significantly higher femur strength (ultimate load) than the other experimental groups, and a similar femur strength as the Control + Fe + DHA/EPA group. This study shows that only combined iron and DHA/EPA supplementation can prevent bone impairments in offspring of female rats consuming an iron and n-3 FA deficient diet preconception.

Effects and Reversibility of Pre- and Post-natal Iron and Omega-3 Fatty Acid Deficiency, Alone and in Combination, on Bone Development in Rats

Both iron and omega-3 (n-3) polyunsaturated fatty acids may play an important role in bone development. The aim of this study was to investigate the effects of pre- and post-natal iron and n-3 fatty acid deficiency (FAD), alone and in combination, on bone development in rats, and to determine whether effects are reversible when a sufficient diet is provided post-weaning. Using a 2×2-factorial design, 56 female Wistar rats were allocated to one of four diets: (1) control, (2) iron deficient (ID), (3) n-3 FAD or (4) ID and n-3 FAD, and were maintained on the respective diets throughout gestation and lactation. At weaning (post-natal day [PND] 21), offspring (n = 24/group; male:female=1:1) were randomly allocated to either continue with their respective diets or to switch to the control diet until PND 42-45. Bone mineral density (BMD) and bone strength were determined using dual X-ray absorptiometry and three-point bending tests, respectively. Pre- and post-natal ID resulted in significantly lower BMD in the spine and bone strength in the left femur. Both ID and n-3 FAD resulted in lower BMD in the right femur, with an additive reduction in the combined ID and n-3 FAD group vs. controls. While negative effects of pre- and post-natal ID alone were reversed in offspring switched to a control diet post-weaning, lower BMD and bone strength persisted in offspring with combined ID and n-3 FAD during the prenatal and early post-natal period. Effects were not sex-specific. These results indicate that ID during early life may negatively influence bone development, with potential additive effects of n-3 FAD. While the effects of ID alone seem reversible, a combined ID and n-3 FAD may result in irreversible deficits in bone development.

High-dose vitamin D supplementation in pregnancy and 25(OH)D sufficiency in childhood reduce the risk of fractures and improve bone mineralization in childhood: Follow-up of a randomized clinical trial

BACKGROUND

Exposure to vitamin D in early life has been associated with improved bone mineralization, but no studies have investigated the combined effect of pregnancy supplementation and childhood 25(OH)D concentrations on bone health.

METHODS

We analyzed the effect of serum 25(OH)D concentrations at age 6 months and 6 years and the combined effect with prenatal high-dose vitamin D (2800 vs. 400 IU/day) on bone mineral density (BMD) and content (BMC) assessed by dual-energy X-ray absorptiometry (DXA) scans at age 3 and 6 years and longitudinal risk of fractures in a double-blinded, randomized clinical trial in the Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC₂₀₁₀) mother-child cohort with enrollment from March 4, 2009, to November 17, 2010, and clinical follow-up until January 31, 2019 (NCT00856947). All participants randomized to intervention and with complete data were included in the analyses.

FINDINGS

At age 6 months, serum 25(OH)D concentration was measured in 93% (n = 541) of 584 children. Children with sufficient (≥ 75 nmol/l) vs. insufficient (< 75 nmol/l) concentrations did not have lower risk of fractures: incidence rate ratio (95% CI); 0.64 (0.37;1.11), p = 0.11. However, vitamin D sufficient children from mothers receiving high-dose supplementation during pregnancy had a 60% reduced incidence of fractures compared with vitamin D insufficient children from mothers receiving standard-dose: 0.40 (0.19;0.84), p = 0.02.At age 6 years, serum 25(OH)D concentration was measured in 83% (n = 318) of 383 children with available DXA data. Whole-body bone mineralization was higher in vitamin D sufficient children at age 6 years; BMD, adjusted mean difference (aMD) (95% CI): 0.011 g/cm² (0.001;0.021), p = 0.03, and BMC, aMD: 12.3 g (-0.8;25.4), p = 0.07, with the largest effect in vitamin D sufficient children from mothers receiving high-dose vitamin D supplementation; BMD, aMD: 0.016 g/cm² (0.002;0.030), p = 0.03, and BMC, aMD: 23.5 g (5.5;41.5), p = 0.01.

INTERPRETATION

Childhood vitamin D sufficiency improved bone mineralization and in combination with prenatal high-dose vitamin D supplementation reduced the risk of fractures.

FUNDING

The study was supported by The Lundbeck Foundation R16-A1694, The Danish Ministry of Health 903,516, The Danish Council for Strategic Research 0603-00280B and The European Research Council 946,228.

The Assessment of the Supply of Calcium and Vitamin D in the Diet of Women Regularly Practicing Sport

INTRODUCTION

The appropriate intake of calcium and vitamin D in women's diet is significant for a proper maintenance of the skeletal system.

RESEARCH AIM

The aim of the research was to assess the calcium and vitamin D supply in a diet among women regularly practicing sport.

METHODOLOGY

The research was completed by 593 women at the age of 18-50 (median 25) who played sports regularly (at least 2 times a week). To assess the calcium and vitamin D intake, short Food Frequency Questionnaires for calcium and vitamin D (VIDEO-FFQ) were used. The examined group was provided with the questionnaires via social media. To assess intake levels, the authors applied the group-based cutoff point method (calcium norm was EAR 800 mg/day; vitamin D norm was AI 15 μg/day).

RESULTS

The median of calcium and vitamin D intake in a diet was 502 mg/day and 5.2 μg/day, respectively (Q25 and Q75 for calcium was 387 mg/day and 627 mg/day, respectively, and for vitamin D was 3.4 μg/day and 8.2 μg/day, respectively). In relation to the EAR norm for calcium and AI norm for vitamin D, 92.0% of the examined participants in a group demonstrated lower than recommended calcium intake levels and 97.3% showed lower than recommended vitamin D intake levels. Calcium and vitamin D supplementation was used by 13.1% (in this subgroup, 11.5% of the examined group members did not need it) and 56.8% of the examined women (in this subgroup, 2.4% of the examined group did not need it), respectively. After including the calcium and vitamin D intake, the supply median for the whole group was 535 mg/day and 28.8 μg/day, respectively (Q25 and Q75 for calcium was 402 mg/day and 671 mg/day, and for vitamin D was 6.3 µg/day and 55.7 μg/day, respectively); 87.5% of the examined participants did not meet the EAR norms for calcium and 42.0% did not meet the AI norm for vitamin D. Among the women supplementing calcium, 58.9% did not reach the reference intake value; however, all women supplementing vitamin D fulfilled the expected nutritional need.

CONCLUSIONS

It is important to educate women about the necessity to provide the body with proper calcium and vitamin D intake levels in a diet in order to avoid health problems resulting from the deficit of the nutrients.

Tracking of bone mass from childhood to puberty: a 7-year follow-up. The CHAMPS study DK

Bone mass in childhood is highly influenced by puberty. At the same age, bone mass was higher for pubertal than pre-pubertal children. A high level of tracking during 7 years from childhood through puberty was shown, indicating that early levels of bone mass may be important for later bone health.

INTRODUCTION

Bone mass development in childhood varies by sex and age, but also by pubertal stage. The objectives of this study were to (1) describe bone mass development in childhood as it relates to pubertal onset and to (2) determine the degree of tracking from childhood to adolescence.

METHODS

A longitudinal study with 7 years of follow-up was initiated in 2008 to include 831 children (407 boys) aged 8 to 17 years. Participants underwent whole body dual-energy X-ray absorptiometry (DXA) scanning, blood collection to quantify luteinizing hormone levels, and Tanner stage self-assessment three times during the 7-year follow-up. Total body less head bone mineral content, areal bone mineral density, and bone area were used to describe development in bone accrual and to examine tracking over 7 years.

RESULTS

Bone mass in pubertal children is higher than that of pre-pubertal children at the same age. Analysing tracking with quintiles of bone mass Z-scores in 2008 and 2015 showed that more than 80% of participants remained in the same or neighbouring quintile over the study period. Tracking was confirmed by correlation coefficients between Z-scores at baseline and 7-year follow-up (range, 0.80-0.84).

CONCLUSIONS

Bone mass is highly influenced by pubertal onset, and pubertal stage should be considered when examining children's bone health. Because bone mass indices track from childhood into puberty, children with low bone mass may be at risk of developing osteoporosis later in life.

Tracking of Areal Bone Mineral Density From Age Eight to Young Adulthood and Factors Associated With Deviation From Tracking: A 17-Year Prospective Cohort Study

We have previously shown that bone mineral density (BMD) tracks strongly from age 8 to 16 years. This study aimed to describe whether this strong tracking continued to age 25 years and describe factors associated with deviation from tracking. Ninety-nine participants were followed from age 8 to 25 years and 197 participants from age 16 to 25 years. Outcomes measured were BMD at the spine, hip, and total body (by dual-energy X-ray absorptiometry [DXA]). Other factors measured were anthropometrics, inhaled corticosteroids (ICS) use, history of being breastfed, sports participation, fitness (by physical work capacity [PWC₁₇₀ ]), lean mass (LM), and fat mass (FM) (by DXA). There was moderate to strong tracking of BMD from age 8 to 25 years (correlation coefficients: males, 0.59 to 0.65; females, 0.70 to 0.82) and strong tracking from age 16 to 25 years (males, 0.81 to 0.83; females, 0.84 to 0.88) after adjustment for change in body size. From age 8 to 25 years, 54% to 56% of participants kept their BMD tertile position. PWC₁₇₀ at age 8 years, relative and absolute change in LM, and sports participation at age 25 years predicted males would improve their tertile position or remain in the highest tertile of spine or hip BMD. However, relative and absolute change in FM had the opposite association in males while absolute change in FM predicted positive deviation in females. From age 16 to 25 years, LM, PWC₁₇₀ , sports participation at age 16 years, and change in LM, PWC₁₇₀ , and sports participation at age 25 years predicted positive deviation in males. LM at age 16 years was positively associated and PWC₁₇₀ negatively associated with positive deviation in females. BMD tracks from childhood to early adulthood in both males and females. There appears to be greater capacity to alter tracking before age 16 years. Increasing LM in both sexes and improving fitness and sports participation in males during growth might be effective strategies to improve BMD in early adulthood. © 2017 American Society for Bone and Mineral Research.

Perfluoroalkyl substances, bone density, and cardio-metabolic risk factors in obese 8-12 year old children: A pilot study

BACKGROUND AND OBJECTIVE

Perfluoroalkyl substances (PFASs), including perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), and perfluorononanoic acid (PFNA), have been associated with adverse bone, and metabolic changes in adults. However association of PFASs with bone health in children is understudied. Considering their role as endocrine disruptors, we examined relationships of four PFASs with bone health in children.

METHODS

In a cross sectional pilot study, 48 obese children aged 8-12 years were enrolled from Dayton's Children Hospital, Ohio. Anthropometric, clinical and biochemical assessments of serum were completed. Serum PFASs were measured by UPLC-ESI-MS/MS. In a subset of 23 children, bone health parameters were measured using calcaneal quantitative ultrasound (QUS).

RESULTS

While PFASs exposure was associated with a consistent negative relationship with bone health parameters, among four PFASs tested, only PFNA showed a significant negative relationship with bone parameter (β [95% CI], = - 72.7 [- 126.0, - 19.6], p = .010). PFNA was also associated with raised systolic blood pressure (p = .008), low density lipoprotein cholesterol (LDL-C; p < .001), and total cholesterol (TC; p = .014). In addition, both PFOA and PFOS predicted elevation in LDL-C, and PFOA predicted increased TC, as well. In this analysis, PFASs were not strongly related to thyroid hormones, 25-hydroxy vitamin D, liver enzymes, or glucose homeostasis.

CONCLUSION

PFASs exposure in obese children may play a role in adverse skeletal and cardiovascular risk profiles.

Changes and tracking of bone mineral density in late adolescence: the Tromsø Study, Fit Futures

Areal bone mineral density (aBMD) predicts future fracture risk. This study explores the development of aBMD and associated factors in Norwegian adolescents. Our results indicate a high degree of tracking of aBMD levels in adolescence. Anthropometric measures and lifestyle factors were associated with deviation from tracking.

PURPOSE

Norway has one of the highest reported incidences of hip fractures. Maximization of peak bone mass may reduce future fracture risk. The main aims of this study were to describe changes in bone mineral levels over 2 years in Norwegian adolescents aged 15-17 years at baseline, to examine the degree of tracking of aBMD during this period, and to identify baseline predictors associated with positive deviation from tracking.

METHODS

In 2010-2011, all first year upper secondary school students in Tromsø were invited to the Fit Futures study and 1038 adolescents (93%) attended. We measured femoral neck (FN), total hip (TH), and total body (TB) aBMD as g/cm² by DXA. Two years later, in 2012-2013, we invited all participants to a follow-up survey, providing 688 repeated measures of aBMD.

RESULTS

aBMD increased significantly (p < 0.05) at all skeletal sites in both sexes. Mean annual percentage increase for FN, TH, and TB was 0.3, 0.5, and 0.8 in girls and 1.5, 1.0, and 2.0 in boys, respectively (p < 0.05). There was a high degree of tracking of aBMD levels over 2 years. In girls, several lifestyle factors predicted a positive deviation from tracking, whereas anthropometric measures appeared influential in boys. Baseline z-score was associated with lower odds of upwards drift in both sexes.

CONCLUSIONS

Our results support previous findings on aBMD development in adolescence and indicate strong tracking over 2 years of follow-up. Baseline anthropometry and lifestyle factors appeared to alter tracking, but not consistently across sex and skeletal sites.

The National Osteoporosis Foundation's position statement on peak bone mass development and lifestyle factors: a systematic review and implementation recommendations

Lifestyle choices influence 20-40 % of adult peak bone mass. Therefore, optimization of lifestyle factors known to influence peak bone mass and strength is an important strategy aimed at reducing risk of osteoporosis or low bone mass later in life. The National Osteoporosis Foundation has issued this scientific statement to provide evidence-based guidance and a national implementation strategy for the purpose of helping individuals achieve maximal peak bone mass early in life. In this scientific statement, we (1) report the results of an evidence-based review of the literature since 2000 on factors that influence achieving the full genetic potential for skeletal mass; (2) recommend lifestyle choices that promote maximal bone health throughout the lifespan; (3) outline a research agenda to address current gaps; and (4) identify implementation strategies. We conducted a systematic review of the role of individual nutrients, food patterns, special issues, contraceptives, and physical activity on bone mass and strength development in youth. An evidence grading system was applied to describe the strength of available evidence on these individual modifiable lifestyle factors that may (or may not) influence the development of peak bone mass (Table 1). A summary of the grades for each of these factors is given below. We describe the underpinning biology of these relationships as well as other factors for which a systematic review approach was not possible. Articles published since 2000, all of which followed the report by Heaney et al. [1] published in that year, were considered for this scientific statement. This current review is a systematic update of the previous review conducted by the National Osteoporosis Foundation [1]. [Table: see text] Considering the evidence-based literature review, we recommend lifestyle choices that promote maximal bone health from childhood through young to late adolescence and outline a research agenda to address current gaps in knowledge. The best evidence (grade A) is available for positive effects of calcium intake and physical activity, especially during the late childhood and peripubertal years-a critical period for bone accretion. Good evidence is also available for a role of vitamin D and dairy consumption and a detriment of DMPA injections. However, more rigorous trial data on many other lifestyle choices are needed and this need is outlined in our research agenda. Implementation strategies for lifestyle modifications to promote development of peak bone mass and strength within one's genetic potential require a multisectored (i.e., family, schools, healthcare systems) approach.

A Pediatric Bone Mass Scan has Poor Ability to Predict Peak Bone Mass: An 11-Year Prospective Study in 121 Children

This 11-year prospective longitudinal study examined how a pre-pubertal pediatric bone mass scan predicts peak bone mass. We measured bone mineral content (BMC; g), bone mineral density (BMD; g/cm(2)), and bone area (cm(2)) in femoral neck, total body and lumbar spine by dual-energy X-ray absorptiometry in a population-based cohort including 65 boys and 56 girls. At baseline all participants were pre-pubertal with a mean age of 8 years (range 6-9), they were re-measured at a mean 11 years (range 10-12) later. The participants were then mean 19 years (range 18-19), an age range that corresponds to peak bone mass in femoral neck in our population. We calculated individual BMC, BMD, and bone size Z scores, using all participants at each measurement as reference and evaluated correlations between the two measurements. Individual Z scores were also stratified in quartiles to register movements between quartiles from pre-pubertal age to peak bone mass. The correlation coefficients (r) between pre-pubertal and young adulthood measurements for femoral neck BMC, BMD, and bone area varied between 0.37 and 0.65. The reached BMC value at age 8 years explained 42 % of the variance in the BMC peak value; the corresponding values for BMD were 31 % and bone area 14 %. Among the participants with femoral neck BMD in the lowest childhood quartile, 52 % had left this quartile at peak bone mass. A pediatric bone scan with a femoral neck BMD value in the lowest quartile had a sensitivity of 47 % [95 % confidence interval (CI) 28, 66] and a specificity of 82 % (95 % CI 72, 89) to identify individuals who would remain in the lowest quartile at peak bone mass. The pre-pubertal femoral neck BMD explained only 31 % of the variance in femoral neck peak bone mass. A pre-pubertal BMD scan in a population-based sample has poor ability to predict individuals who are at risk of low peak bone mass.

Longitudinal tracking of dual-energy X-ray absorptiometry bone measures over 6 years in children and adolescents: persistence of low bone mass to maturity

OBJECTIVES

Early assessment of bone mass may be useful for predicting future osteoporosis risk if bone measures "track" during growth. This prospective longitudinal multicenter study examined tracking of bone measures in children and adolescents over 6 years to sexual and skeletal maturity.

STUDY DESIGN

A total of 240 healthy male and 293 healthy female patients, ages 6-17 years, underwent yearly evaluations of height, weight, body mass index, skeletal age, Tanner stage, and dual-energy x-ray absorptiometry (DXA) bone measurements of the whole body, spine, hip, and forearm for 6 years. All subjects were sexually and skeletally mature at final follow-up. Correlation was performed between baseline and 6-year follow-up measures, and change in DXA Z-scores was examined for subjects who had baseline Z < -1.5.

RESULTS

DXA Z-scores (r = 0.66-0.87) had similar tracking to anthropometric measures (r = 0.64-0.74). Tracking was stronger for bone mineral density compared with bone mineral content and for girls compared with boys. Tracking was weakest during mid- to late puberty but improved when Z-scores were adjusted for height. Almost all subjects with baseline Z < -1.5 had final Z-scores below average, with the majority remaining less than -1.0.

CONCLUSIONS

Bone status during childhood is a strong predictor of bone status in young adulthood, when peak bone mass is achieved. This suggests that bone mass measurements in children and adolescents may be useful for early identification of individuals at risk for osteoporosis later in life.

A pediatric bone mass scan has poor ability to predict adult bone mass: a 28-year prospective study in 214 children

As the correlation of bone mass from childhood to adulthood is unclear, we conducted a long-term prospective observational study to determine if a pediatric bone mass scan could predict adult bone mass. We measured cortical bone mineral content (BMC [g]), bone mineral density (BMD [g/cm(2)]), and bone width (cm) in the distal forearm by single photon absorptiometry in 120 boys and 94 girls with a mean age of 10 years (range 3-17) and mean 28 years (range 25-29) later. We calculated individual and age-specific bone mass Z scores, using the control cohort included at baseline as reference, and evaluated correlations between the two measurements with Pearson's correlation coefficient. Individual Z scores were also stratified in quartiles to register movements between quartiles from growth to adulthood. BMD Z scores in childhood and adulthood correlated in both boys (r = 0.35, p < 0.0001) and girls (r = 0.50, p < 0.0001) and in both children ≥10 years at baseline (boys r = 0.43 and girls r = 0.58, both p < 0.0001) and children <10 years at baseline (boys r = 0.26 and girls r = 0.40, both p < 0.05). Of the children in the lowest quartile of BMD, 58% had left the lowest quartile in adulthood. A pediatric bone scan with a value in the lowest quartile had a sensitivity of 48% (95% confidence interval [CI] 27-69%) and a specificity of 76% (95% CI 66-84%) to identify individuals who would remain in the lowest quartile also in adulthood. Childhood forearm BMD explained 12% of the variance in adult BMD in men and 25% in women. A pediatric distal forearm BMD scan has poor ability to predict adult bone mass.

Are early growth and nutrition related to bone health in adolescence? The Copenhagen Cohort Study of infant nutrition and growth

BACKGROUND

It is generally accepted that peak bone mass affects later fracture risk in the elderly. The extent to which early nutrition and growth can program later bone health has been examined in only a few studies. In the Copenhagen Cohort Study we showed that breastfed infants had significantly higher serum (s)-osteocalcin concentration than did formula-fed infants.

OBJECTIVE

We investigated whether early nutrition and early growth are associated with later bone mass in adolescence.

DESIGN

Participants were examined at birth; at ages 2, 6, and 9 mo (n = 143); and at age 17 y (n = 109) with anthropometric and s-osteocalcin measures and whole-body dual-energy X-ray absorptiometry (DXA) scanning (age 17 y only). Total body (T) and lumbar spine (LS) DXA values were used.

RESULTS

The duration of exclusive breastfeeding was positively correlated with the sex-adjusted LS bone mineral content (BMC), LS bone area (BA), and LS bone mineral density (BMD) (all P < 0.03) and with size-adjusted LS-BMC (P = 0.075) at 17 y of age. s-Osteocalcin at 6 mo was positively correlated with sex-adjusted LS-BMC and LS-BMD (both P < 0.04) and with size-adjusted LS-BMC (P = 0.047) at 17 y of age. Weight and length at 9 mo and increase in weight and length during the first 9 mo of life were positively correlated with sex-adjusted T-BMC and T-BA at age 17 y (all P < 0.04).

CONCLUSIONS

Early body size and growth in infancy are related to bone mass in late adolescence. Furthermore, the duration of exclusive breastfeeding and the markers of bone turnover at 6 mo seem to be positively related to LS bone mass at age 17 y.

Pubertal timing and body mass index gain from birth to maturity in relation with femoral neck BMD and distal tibia microstructure in healthy female subjects

Childhood body mass index (BMI) gain is linked to hip fracture risk in elderly. In healthy girls, menarcheal age is inversely related to BMI gain during childhood and to femoral neck areal bone mass density (aBMD) and distal tibia structural components at maturity. This study underscores the importance of pubertal timing in age-related fragility fracture risk.

INTRODUCTION

Recent data point to a relationship between BMI change during childhood and hip fracture risk in later life. We hypothesized that BMI development is linked to variation in pubertal timing as assessed by menarcheal age (MENA) which in turn, is related to peak bone mass (PBM) and hip fracture risk in elderly.

METHODS

We studied in a 124 healthy female cohort the relationship between MENA and BMI from birth to maturity, and DXA-measured femoral neck (FN) aBMD at 20.4 year. At this age, we also measured bone strength related microstructure components of distal tibia by HR-pQCT.

RESULTS

At 20.4 ± 0.6 year, FN aBMD (mg/cm(2)), cortical thickness (μm), and trabecular density (mg HA/cm(3)) of distal tibia were inversely related to MENA (P = 0.023, 0.015, and 0.041, respectively) and positively to BMI changes from 1.0 to 12.4 years (P = 0.031, 0.089, 0.016, respectively). Significant inverse (P < 0.022 to <0.001) correlations (R = -0.21 to -0.42) were found between MENA and BMI from 7.9 to 20.4 years, but neither at birth nor at 1.0 year. Linear regression indicated that MENA Z-score was inversely related to BMI changes not only from 1.0 to 12.4 years (R = -0.35, P = 0.001), but also from 1.0 to 8.9 years, (R = -0.24, P = 0.017), i.e., before pubertal maturation.

CONCLUSION

BMI gain during childhood is associated with pubertal timing, which in turn, is correlated with several bone traits measured at PBM including FN aBMD, cortical thickness, and volumetric trabecular density of distal tibia. These data complement the reported relationship between childhood BMI gain and hip fracture risk in later life.