Childhood growth predicts higher bone mass and greater bone area in early old age: findings among a subgroup of women from the Helsinki Birth Cohort Study

Trans-ancestral genome-wide association study of longitudinal pubertal height growth and shared heritability with adult health outcomes

BACKGROUND

Pubertal growth patterns correlate with future health outcomes. However, the genetic mechanisms mediating growth trajectories remain largely unknown. Here, we modeled longitudinal height growth with Super-Imposition by Translation And Rotation (SITAR) growth curve analysis on ~ 56,000 trans-ancestry samples with repeated height measurements from age 5 years to adulthood. We performed genetic analysis on six phenotypes representing the magnitude, timing, and intensity of the pubertal growth spurt. To investigate the lifelong impact of genetic variants associated with pubertal growth trajectories, we performed genetic correlation analyses and phenome-wide association studies in the Penn Medicine BioBank and the UK Biobank.

RESULTS

Large-scale growth modeling enables an unprecedented view of adolescent growth across contemporary and 20th-century pediatric cohorts. We identify 26 genome-wide significant loci and leverage trans-ancestry data to perform fine-mapping. Our data reveals genetic relationships between pediatric height growth and health across the life course, with different growth trajectories correlated with different outcomes. For instance, a faster tempo of pubertal growth correlates with higher bone mineral density, HOMA-IR, fasting insulin, type 2 diabetes, and lung cancer, whereas being taller at early puberty, taller across puberty, and having quicker pubertal growth were associated with higher risk for atrial fibrillation.

CONCLUSION

We report novel genetic associations with the tempo of pubertal growth and find that genetic determinants of growth are correlated with reproductive, glycemic, respiratory, and cardiac traits in adulthood. These results aid in identifying specific growth trajectories impacting lifelong health and show that there may not be a single "optimal" pubertal growth pattern.

Peak Bone Mass Formation: Modern View of the Problem

Peak bone mass is the amount of bone tissue that is formed when a stable skeletal state is achieved at a young age. To date, there are no established peak bone mass standards nor clear data on the age at which peak bone mass occurs. At the same time, the level of peak bone mass at a young age is an important predictor of the onset of primary osteoporosis. The purpose of this review is to analyze the results of studies of levels of peak bone mass in general, the age of its onset, as well as factors influencing its formation. Factors such as hormonal levels, body composition, physical activity, nutrition, heredity, smoking, lifestyle, prenatal predictors, intestinal microbiota, and vitamin and micronutrient status were considered, and a comprehensive scheme of the influence of these factors on the level of peak bone mass was created. Determining the standards and timing of the formation of peak bone mass, and the factors affecting it, will help in the development of measures to prevent its shortage and the consequent prevention of osteoporosis and concomitant diseases.

Linear growth and relative weight gain in childhood and bone mass in adolescence: findings from the Pelotas (Brazil) 2004 birth cohort

With the objective to investigate the relationship of weight and height growth with bone mass at 11 years, we found that boys who grew in weight and height, especially at 48 months, and girls, who grew in weight at 24 months and height at 11 years, gained more bone mass.

PURPOSE

To investigate independent relationships of linear growth and relative weight gain during defined periods of infancy, childhood, and early adolescence with areal bone mineral density (aBMD) of three sites at 11 years.

METHODS

Data on weight and length/height were obtained at birth, 3, 12, and 24 months, and the ages of 4, 6, and 11. The outcome was whole body, femoral neck, and lumbar spine aBMD (g/cm2) measured at 11 years using dual-energy X-ray absorptiometry. The effects of weight gain and linear growth were analyzed using conditional relative weight and conditional length/height. Associations between conditional growth and outcomes were analyzed using linear regression, adjusted for multiple confounders.

RESULTS

Individuals with data available for exposures and bone outcomes were 2875 and comprised the sample. For boys, the greatest magnitude of increase for whole body and height gain was at 48 months (β 0.014, 95% CI 0.010; 0.018). For girls, higher aBMD was observed for those with greater height gain at 11 years, representing for lumbar spine an increase of 0.056 g/cm2 (95% CI 0.050; 0.062). For body weight, among boys, the greatest magnitude in the whole body was also associated with weight gain at 48 months (β 0.014, 95% CI 0.010; 0.018). For girls, the highest coefficient was at 24 months, representing for lumbar spine an increase of 0.028 g/cm2, (95% CI 0.021; 0.035).

CONCLUSION

Positive associations were demonstrated between length/height and weight gain and aBMD in both sexes, with emphasis on girls' aBMD in response to the linear growth achieved mainly at 11 years.

Birth weight associated with dual energy X-ray absorptiometry-determined muscle-bone unit in young healthy women from the Nutritionists' Health Study

Muscle and bone have been considered a functional unit that grows together early in life, deteriorates with aging, and can cause osteosarcopenia. Due to its importance in public health, detecting risk factors in early life is desirable. This study examined whether birth weight (BW) was associated with muscle-bone unit using dual energy X-ray absorptiometry (DXA) parameters in young women from the Nutritionists' Health Study (NutriHS), a cohort study of undergraduates and Nutrition graduates. This cross-sectional analysis included 170 young healthy women who answered early life events-questionnaire, and had anthropometric, muscle tests and DXA-determined body composition and bone densitometry (iDXA-Lunar®). A blood sample was obtained for a subsample of 148 participants. Appendicular skeletal muscle mass index (ASMI) was calculated. BW was categorized in quartiles (BWq) and variables of interest compared by ANOVA. Associations of BWq with calf circumference (CC), handgrip, muscle performance tests, ASMI, bone mineral density and content (BMD and BMC), and plasma glucose, lipids, insulin, and 25-hydroxyvitamin D were performed using multiple linear regression and directed acyclic graph-recommended adjustments. Mean values of age, body mass index, and BW were 23.0 years (20.0-28.0), 22.9 ± 2.9 kg/m2, and 3199 ± 424 g, respectively. Comparing variables across BWq, significant differences in CC, handgrip, ASMI, and total body BMC were detected. Regression models adjusted for confounders showed associations of BWq with CC (β = 0.72, p = 0.005), handgrip (β = 1.53, p = 0.001), ASMI (β = 0.16, p = 0.022), total body BMC (β = 64.8, p = 0.005), total femur BMC (β = 0.70, p = 0.041), total body BMD (β = 0.02, p = 0.043), and lumbar spine BMD (β = 0.03, p = 0.028). We conclude that BW is associated with muscle-bone unit using DXA-parameters in Brazilian young healthy women from the NutriHS, suggesting a role for intrauterine environment for musculoskeletal health.

Growth from birth to adolescence and bone mineral density in young adults: The 1993 Pelotas birth cohort

BACKGROUND

The study examined the association of body size (weight and length) at birth and gain in height and weight during childhood and adolescence with areal bone mineral density (aBMD) in adulthood for women and men.

METHODS

756 members (335 men and 421 women) of the 1993 Pelotas (Brazil) Birth cohort were studied. Data on weight and length/height were obtained at birth and subsequent follow-ups at 1, 4, 11, 15, 18, and 22 years of age and specific z scores were calculated by sex. The outcome was whole body aBMD (g/cm²) measured at 22 years of age using dual-energy X-ray absorptiometry (DXA). The effects of exposures, weight and length/height gain, were analyzed using conditional relative weight (CWh) and conditional length/height (CH). Linear regression models were adjusted for multiple confounders, including mother's educational level, family income, maternal smoking during pregnancy, gestational age, breastfeeding and skin color.

RESULTS

In the adjusted models, among men greater height gain at 4, 11, and 18 years of age was associated with higher whole body aBMD, and the result with greatest magnitude was at 11 years of age (β 0.018 g/cm²; 95%CI 0.006; 0.030). Among women, aBMD was associated with height gain at all assessments from 1-15 years, with greatest effect size at 4 years of age (β 0.017 g/cm²; 95%CI 0.007; 0.027). Regarding to body weight, among men, greater weight at 4 and 15 years were associated with higher aBMD, with the highest coefficients for 15 years of age (β 0.015 g/cm²; 95%CI 0.003; 0.027); for women, except at birth, all weight gain variables were associated with aBMD and the highest coefficients were observed at 4 years (β 0.025 g/cm²; 95%CI 0.015; 0.035).

CONCLUSIONS

In this birth cohort, height and weight gain, especially from 4 to 15 years have important positive implications for aBMD to early adulthood.

Early childhood as a sensitive period for the effect of growth on childhood bone mass: Evidence from Generation XXI birth cohort

BACKGROUND

To identify sensitive periods for the effect of early life growth on childhood bone mass we compared the associations between weight and length/height velocities from birth to age six and bone mineral content (BMC) and areal density (aBMD) at 7 years of age.

METHODS

We analyzed data from 1853 participants from the Generation XXI birth cohort scanned with a whole body dual-energy X-ray absorptiometry system. Velocities of growth in weight and length/height were obtained through linear spline multilevel models on the basis of data collected during routine health examinations. Using linear regression we computed associations of birth weight, birth length, five weight velocities ("early neonatal": 0-10 days, "early infancy": 10 days-3 months, "late infancy": 3-12 months, "early childhood": 1-3 years, and "later childhood": 3-6 years) and four length/height velocities ("early infancy": 0-3 months, "late infancy": 3-12 months, "early childhood": 1-3 years, and "later childhood": 3-6 years) with outcomes BMC, aBMD, height and height-adjusted BMC at age seven. Confounding by maternal and child characteristics was addressed and effects of growth velocities were adjusted to preceding growth.

RESULTS

Weight and length/height velocities up to the age of six were associated with increased bone mass, areal density and height at 7 years with the strongest associations observed for growth in early childhood. In this age period, after concurrent height and confounder adjustment, one standard deviation (SD) increase in weight velocity was associated with higher BMC z-scores: 0.27 (95%CI: 0.22, 0.32) in girls and 0.24 (95%CI: 0.19, 0.29) in boys. Height velocity was also associated with greater height-adjusted BMC z-score: 0.12 (95%CI: 0.07, 0.17) per SD in girls and 0.11 (95%CI: 0.06, 0.16) in boys. The pattern of associations was similar, albeit attenuated, after adjusting for preceding growth.

CONCLUSION

Growth in second and third years of life may represent a sensitive period for the effect of growth on childhood bone mass, partly through their effect on concurrent body size.

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.

Epigenetics of Skeletal Diseases

PURPOSE OF REVIEW

Epigenetic mechanisms modify gene activity in a stable manner without altering DNA sequence. They participate in the adaptation to the environment, as well as in the pathogenesis of common complex disorders. We provide an overview of the role of epigenetic mechanisms in bone biology and pathology.

RECENT FINDINGS

Extensive evidence supports the involvement of epigenetic mechanisms (DNA methylation, post-translational modifications of histone tails, and non-coding RNAs) in the differentiation of bone cells and mechanotransduction. A variety of epigenetic abnormalities have been described in patients with osteoporosis, osteoarthritis, and skeletal cancers, but their actual pathogenetic roles are still unclear. A few drugs targeting epigenetic marks have been approved for neoplastic disorders, and many more are being actively investigated. Advances in the field of epigenetics underscore the complex interactions between genetic and environmental factors as determinants of osteoporosis and other common disorders. Likewise, they help to explain the mechanisms by which prenatal and post-natal external factors, from nutrition to psychological stress, impact our body and influence the risk of later disease.

Maternal nutrition and the developmental origins of osteoporosis in offspring: Potential mechanisms and clinical implications

Osteoporosis, the most frequent metabolic disorder of bone, is a complex disease with a multifactorial origin that is influenced by genes and environments. However, the pathogenesis of osteoporosis has not been fully elucidated. The theory of "Developmental Origins of Health and Disease" indicates that early life environment exposure determines the risks of cardiometabolic diseases in adulthood. However, investigations into the effects of maternal nutrition and nutrition exposure during early life on the development of osteoporosis are limited. Recently, emerging evidence has strongly suggested that maternal nutrition has long-term influences on bone metabolism in offspring, and epigenetic modifications maybe the underlying mechanisms of this process. This review aimed to address maternal nutrition and its implications for the developmental origins of osteoporosis in offspring. It is novel in providing a theoretical basis for the early prevention of osteoporosis. Impact statement Our review aimed to address maternal nutrition and its implications for the developmental origins of osteoporosis in offspring, that can novelly provide a theoretical basis for the early prevention of osteoporosis.