Relations among maternal physical activity during pregnancy and child body composition.

OBJECTIVE: Physical activity (PA) during pregnancy is associated with lower neonatal fat mass, but associations with child body composition are mixed. The purpose of this study was to examine associations between trimester-specific pregnancy PA and child body composition at 4 years. METHODS: Participants of the Minnesota Infant Nutrition, Neurodevelopment, and Obesity Study were asked to recall participation in any moderate or vigorous PA in the first (T1), second (T2) and third (T3) trimesters at about 5 years postpartum. Child fat mass and fat-free mass were measured via air displacement plethysmography at 2 weeks, 3 months and 4 years of age. Multivariate linear regression was used for analyses. RESULTS: Of 51 possible participants, 37 recalled pregnancy PA. Any vigorous PA in T3 was associated with lower child fat mass at 4 years (adjß = -1.077, p < 0.05). CONCLUSION: Late pregnancy PA may have lasting benefits for child body composition. Replication of these findings is needed in a larger sample with prospective measures.

The positive association of infant weight gain with adulthood body mass index has strengthened over time in the Fels Longitudinal Study.

BACKGROUND: Infant weight gain is positively related to adulthood body mass index (BMI), but it is unknown whether or not this association is stronger for individuals born during (compared with before) the obesity epidemic. OBJECTIVES: The aim of the study was to examine how the infant weight gain-adulthood BMI association might have changed across successive birth year cohorts spanning most of the 20th century. METHODS: The sample comprised 346 participants in the Fels Longitudinal Study. Confounder-adjusted regression models were used to test the associations of conditional weight-for-length Z-score, capturing weight change between ages 0-2 years, with young adulthood BMI and blood pressure, including cohort [1933-1949 {N = 137}, 1950-1969 {N = 108}, 1970-1997 {N = 101}] as an effect modifier. RESULTS: Conditional weight-for-length Z-score was positively related to adulthood BMI, but there was significant effect modification by birth year cohort such that the association was over two times stronger in the 1970-1997 cohort (ß 2.31; 95% confidence interval 1.59, 3.03) compared with the 1933-1949 (0.98; 0.31, 1.65) and 1950-1969 (0.87; 0.21, 1.54) cohorts. A similar pattern was found for systolic blood pressure. CONCLUSIONS: The infant weight gain-adulthood BMI association was over two times stronger among a cohort born during the obesity epidemic era compared with cohorts born earlier in the 20th century.

Novel associations between blood DNA methylation and body mass index in middle-aged and older adults.

BACKGROUND/OBJECTIVES: There is increasing evidence of a relationship between blood DNA methylation and body mass index (BMI). We aimed to assess associations of BMI with individual methylation measures (CpGs) through a cross-sectional genome-wide DNA methylation association study and a longitudinal analysis of repeated measurements over time. SUBJECTS/METHODS: Using the Illumina Infinium HumanMethylation450 BeadChip, DNA methylation measures were determined in baseline peripheral blood samples from 5361 adults recruited to the Melbourne Collaborative Cohort Study (MCCS) and selected for nested case-control studies, 2586 because they were subsequently diagnosed with cancer (cases) and 2775 as controls. For a subset of 1088 controls, these measures were repeated using blood samples collected at wave 2 follow-up, a median of 11 years later; weight was measured at both time points. Associations between BMI and blood DNA methylation were assessed using linear mixed-effects regression models adjusted for batch effects and potential confounders. These were applied to cases and controls separately, with results combined through fixed-effects meta-analysis. RESULTS: Cross-sectional analysis identified 310 CpGs associated with BMI with P<1.0 × 10-7, 225 of which had not been reported previously. Of these 225 novel associations, 172 were replicated (P<0.05) using the Atherosclerosis Risk in Communities (ARIC) study. We also replicated using MCCS data (P<0.05) 335 of 392 associations previously reported with P<1.0 × 10-7, including 60 that had not been replicated before. Associations between change in BMI and change in methylation were observed for 34 of the 310 strongest signals in our cross-sectional analysis, including 7 that had not been replicated using the ARIC study. CONCLUSIONS: Together, these findings suggest that BMI is associated with blood DNA methylation at a large number of CpGs across the genome, several of which are located in or near genes involved in ATP-binding cassette transportation, tumour necrosis factor signalling, insulin resistance and lipid metabolism.

Maternal executive function, infant feeding responsiveness and infant growth during the first 3 months.

BACKGROUND: There is limited research in young infants, particularly <3 months of age, on maternal feeding practices in spite of increasing evidence that early weight gain velocity is a determinant of later obesity risk. OBJECTIVE: To examine associations between maternal executive function (cognitive control over one's own behaviour), maternal feeding decisions and infant weight and adiposity gains. METHODS: We used a checklist to assess cues mothers use to decide when to initiate and terminate infant feedings at 2 weeks and 3 months of age (N = 69). Maternal executive function was assessed using the NIH Toolbox Cognition Battery subtests for executive function and infant body composition using air displacement plethysmography. RESULTS: Mothers with higher executive function reported relying on fewer non-satiety cues at 2 weeks of age (ß = -0.29, p = 0.037) and on more infant hunger cues at 3 months of age (ß = 0.31, p = 0.018) in their decisions on initiating and terminating feedings. Responsive feeding decisions, specifically the use of infant-based hunger cues at 3 months, in turn were associated with lower gains in weight-for-length (ß = -0.30, p = 0.028) and percent body fat (ß = -0.2, p = 0.091; non-covariate adjusted ß = -0.27, p = 0.029). CONCLUSIONS: These findings show both an association between maternal executive function and responsive feeding decisions and an association between responsive feeding decisions and infant weight and adiposity gains. The causal nature and direction of these associations require further investigation.

Associations between human breast milk hormones and adipocytokines and infant growth and body composition in the first 6 months of life.

BACKGROUND: Much is to be learnt about human breast milk (HBM). OBJECTIVES: The purpose of this study is to extend our knowledge of HBM by investigating the role of maternal body mass index (BMI), sex and stage of lactation (month 1 vs. 6) on HBM insulin, glucose, leptin, IL-6 and TNF-α and their associations with infant body composition. METHODS: Thirty-seven exclusively breastfeeding infants (n = 37; 16♀, 21♂), and their mothers (19-47 kg m-2 ) were studied at 1 and 6 months of lactation. Infants had body composition measured (using dual-energy X-ray absorptiometry) and HBM collected. RESULTS: A significant interaction between maternal BMI and infant sex on insulin levels (p = 0.0322) was observed such that insulin was 229% higher in obese mothers nursing female infants than in normal weight mothers nursing female infants and 179% higher than obese mothers nursing male infants. For leptin, a significant association with BMI category was observed (p < 0.0001) such that overweight and obese mothers had 96.5% and 315.1% higher leptin levels than normal weight mothers, respectively. Leptin was also found to have a significant (p = 0.0004) 33.7% decrease from months 1 to 6, controlling for BMI category and sex. A significant inverse relationship between month 1 leptin levels and infant length (p = 0.0257), percent fat (p = 0.0223), total fat mass (p = 0.0226) and trunk fat mass (p = 0.0111) at month 6 was also found. No associations or interactions were observed for glucose, TNF-α or IL-6. CONCLUSIONS: These data demonstrate that maternal BMI, infant sex and stage of lactation affect the compositional make-up of insulin and leptin.

Is infant body mass index associated with adulthood body composition trajectories? An exploratory analysis.

BACKGROUND: Infant body mass index (BMI) is increasingly used as a marker of obesity risk based on its association with young-adulthood BMI. OBJECTIVES: The aim of this study is to test the association of infant BMI with young-adulthood fat mass and fat-free mass, and how this association changes during advancing adulthood. METHODS: Body mass index Z-score at age 9 months was measured in 350 White, non-Hispanic Fels Longitudinal Study participants. This exposure was entered into multilevel models to test its association with trajectories describing 2665 BMI observations and 1388 observations of fat mass index (FMI, kg m-2 ) and fat-free mass index (FFMI, kg m-2 ) between ages 20 and 60 years. RESULTS: Partitioning young-adulthood BMI into its fat and fat-free components, infant BMI Z-score was associated with FFMI (ß = 0.745; 95% confidence interval = 0.367 to 1.124) but not FMI (0.528; -0.055 to 1.110) at age 20 years. Greater infant BMI Z-score was associated with slower age-related increases in all outcomes, such that (looking at 10-year intervals) only FFMI at age 30 years was related to infant BMI Z-score (0.338; 0.119, 0.557). CONCLUSIONS: Focus on infant BMI reduction for adulthood obesity prevention warrants caution as high infant BMI values are associated with greater lean mass, which is protective against ageing changes.

Do anthropometric measures accurately reflect body composition in preterm infants?

BACKGROUND: Recent literature suggests that neonatal adiposity is predictive of later metabolic health, while neonatal lean mass is predictive of later cognitive function amongst preterm infants. Anthropometric indices that accurately reflect neonatal body composition could improve clinical care and aid future research, but their validity has not been systematically tested in preterm infants. OBJECTIVE: To determine the weight/length indices that best reflect neonatal body composition in preterm infants. METHODS: Weight and length were measured, and body composition (fat-free mass (FFM), fat mass (FM) and percent body fat (%BF)) was assessed using air-displacement plethysmography within 72 h of birth in 218 preterm infants. The best weight/length proxy for FFM, FM and %BF were those with the highest proportion variance explained (R2 ) and lowest root mean square error (RMSE) in linear regression models. RESULTS: Among all of the weight/length indices tested, weight/length2 was the best proxy for %BF, but nonetheless exhibited very low variance explained (R2 = 0.27) and high prediction error (RMSE = 3.5% fat). Body weight unadjusted for length was strongly associated with FFM (R2 = 0.97). CONCLUSIONS: No weight/length index accurately reflected %BF. Weight/length indices are not appropriate for assessment of relative adiposity in preterm infants near birth. What's known on this subject: Compared with term infants, preterm infants have increased fat mass and diminished fat-free mass upon hospital discharge. Early adiposity predicts later metabolic health, while early lean mass is predictive of later neurodevelopmental outcomes. Optimal anthropometric proxies for preterm body composition at birth are not established. WHAT THIS STUDY ADDS: Weight is an adequate surrogate for lean mass at birth in preterm infants. There are no weight/length indices that accurately reflect neonatal adiposity at birth.

Sex differences in the rate of abdominal adipose accrual during adulthood: the Fels Longitudinal Study.

OBJECTIVES: The purpose of this analysis was to evaluate sex differences in the rate of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) accrual in adults. Secondary analyses examined differences in the rate of VAT and SAT accrual in premenopausal, perimenopausal and postmenopausal women. SUBJECTS/METHODS: Participants were 472 (60% female) non-Hispanic whites and aged 18-84 years at baseline in whom abdominal VAT and SAT were assessed using multiple-image magnetic resonance imaging at two time points, with an average follow-up of 7.3±2.6 years. Linear regression models were used to examine the effects of sex, baseline age and their interaction on rate of change per year in body composition measures (ΔBMI, ΔVAT and ΔVAT/SAT ratio (ΔVSR)) independent of baseline body composition measures, visit year, income, marital status, physical activity, smoking and alcohol intake. Secondary analyses examined differences in the rate of fat change by menopausal status (premenopausal, perimenopausal, postmenopausal). RESULTS: Levels of body mass index (BMI), VAT and VSR all increased over the 7-year period on average (P<0.001); however, the change in BMI (mean ΔBMI=+0.5%) was far smaller than for VAT (mean ΔVAT=+6.8%), SAT (mean ΔSAT=+2.4%) and VSR (mean ΔVSR=+3.6%). ΔBMI, ΔVAT and ΔSAT decreased linearly with age in both sexes (P<0.01), such that older individuals had lower rates of BMI, VAT and SAT gain, and this deceleration in BMI, VAT and SAT accrual was greater in men than women (P for interaction <0.05). ΔVSR did not vary with age in either sex but remained higher in men than women throughout adulthood. There were no differences in rate of weight or fat gain by menopausal status after adjustment for age. CONCLUSIONS: Men and women continue to accrue abdominal adiposity with age, but the rate of weight and fat gain decreases over time, particularly in men.

Diminished growth and lower adiposity in hyperglycemic very low birth weight neonates at 4 months corrected age.

OBJECTIVE: Characterize the relationship between neonatal hyperglycemia and growth and body composition at 4 months corrected age (CA) in very low birth weight (VLBW) preterm infants. STUDY DESIGN: A prospective study of VLBW appropriate-for-gestation infants (N=53). All blood glucose measurements in the first 14 days and nutritional intake and illness markers until discharge were recorded. Standard anthropometrics and body composition via air displacement plethysmography were measured near term CA and 4 months CA. Relationships between hyperglycemia and anthropometrics and body composition were examined using multivariate linear regression. RESULTS: Infants with >5 days of hyperglycemia were lighter (5345 vs 6455 g, P⩽0.001), shorter (57.9 vs 60.9 cm, P⩽0.01), had smaller occipital-frontal head circumference (39.4 vs 42.0 cm, P⩽0.05) and were leaner (percent body fat 15.0 vs 23.8, P⩽0.01) at 4 months CA than those who did not have hyperglycemia, including after correcting for nutritional and illness factors. CONCLUSIONS: Neonatal hyperglycemia in VLBW infants is associated with decreased body size and lower adiposity at 4 months CA independent of nutritional deficit, insulin use and illness. Downregulation of the growth hormone axis may be responsible. These changes may influence long-term growth and cognitive development.

Body composition at birth in preterm infants between 30 and 36 weeks gestation.

BACKGROUND: The American Academy of Pediatrics calls for aggressive management of preterm infants to achieve body composition approximating that of the healthy infant in utero. Air displacement plethysmography (ADP) has been validated for assessment of body composition in preterm infants and could be used to monitor their nutritional status during hospitalization. Comparative datasets on body composition at birth among healthy, live-born preterm infants are lacking. OBJECTIVE: The aim of this study is to provide the first descriptive fat mass (FM) and fat-free mass (FFM) data from healthy newborn preterm infants at birth as a proxy for healthy in utero body composition. METHODS: Body mass and volume were obtained using ADP within 72 h of birth in 98 singleton, appropriate-for-gestational-age preterm infants. FM and FFM were calculated using the Fomon equation. RESULTS: Measurement with ADP was feasible and well tolerated by infants as young as 30 weeks gestation and <72 h of age. FFM and FM increased linearly over the gestational age range period at rates of 171 and 46 g week(-1) , respectively. Mean values obtained by ADP by gestational week were similar to the previously published reference data from chemical analysis on stillbirths. CONCLUSIONS: Body composition assessment using ADP is feasible in newborn preterm infants and provides group estimates similar to that of the reference fetus. In the future, integrating body composition information into the nutritional management of preterm infants may help to identify new strategies to optimize growth and development in this vulnerable population.

Neonatal hyperglycemia and diminished long-term growth in very low birth weight preterm infants.

OBJECTIVE: To investigate the association between early hyperglycemia and growth and development from hospital discharge to 2 years corrected age (CA) in very low birth weight (VLBW) infants. STUDY DESIGN: Blood glucose levels during the first 14 days after birth, weight, length and occipital-frontal circumference (OFC) at birth, hospital discharge and 4, 12 and 24 months CA, Bayley developmental scores at 12 and 24 months CA, and information on multiple clinical variables were recorded on VLBW preterm infants (N=80). The relationships between hyperglycemia, growth and developmental scores were determined using linear mixed effects regression. RESULT: Hyperglycemia was a strong predictor of poor rate of increase in weight, length and OFC until 24 months CA. Hyperglycemia was not associated with lower scores on the Bayley scales. CONCLUSION: Neonatal hyperglycemia was associated with poor physical growth until at least 2 years CA in this cohort of VLBW preterm infants.

Association of heat shock proteins with all-cause mortality.

Experimental mild heat shock is widely known as an intervention that results in extended longevity in various models along the evolutionary lineage. Heat shock proteins (HSPs) are highly upregulated immediately after a heat shock. The elevation in HSP levels was shown to inhibit stress-mediated cell death, and recent experiments indicate a highly versatile role for these proteins as inhibitors of programmed cell death. In this study, we examined common genetic variations in 31 genes encoding all members of the HSP70, small HSP, and heat shock factor (HSF) families for their association with all-cause mortality. Our discovery cohort was the Rotterdam study (RS1) containing 5,974 participants aged 55 years and older (3,174 deaths). We assessed 4,430 single nucleotide polymorphisms (SNPs) using the HumanHap550K Genotyping BeadChip from Illumina. After adjusting for multiple testing by permutation analysis, three SNPs showed evidence for association with all-cause mortality in RS1. These findings were followed in eight independent population-based cohorts, leading to a total of 25,007 participants (8,444 deaths). In the replication phase, only HSF2 (rs1416733) remained significantly associated with all-cause mortality. Rs1416733 is a known cis-eQTL for HSF2. Our findings suggest a role of HSF2 in all-cause mortality.

Stronger influence of maternal than paternal obesity on infant and early childhood body mass index: the Fels Longitudinal Study.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: Excessive early childhood adiposity is a prevalent and increasing concern in many parts of the world. Parental obesity is one of the several factors previously associated with infant and early childhood weight, length and adiposity. Parental obesity represents a surrogate marker of the complex interplay among genetic, epigenetic and shared environmental factors, and is potentially modifiable. The relative contributions of maternal and paternal body mass index (BMI) to infant and early childhood growth, as well as the timing of such effects, have not been firmly established. WHAT THIS STUDY ADDS: Utilizing serial infant measurements and growth curve modelling, this is the largest study to fully characterize and formally compare associations between maternal and paternal BMI and offspring growth across the entire infancy and early childhood period. Maternal obesity is a stronger determinant of offspring BMI than paternal obesity at birth and from 2 to 3 years of age, suggesting that prevention efforts focused particularly on maternal lifestyle and BMI may be important in reducing excess infant BMI. The observation that maternal BMI effects are not constant, but rather present at birth, wane and re-emerge during late infancy, suggests that there is a window of opportunity in early infancy when targeted interventions on children of obese mothers may be most effective. BACKGROUND/OBJECTIVE: Parental obesity influences infant body size. To fully characterize their relative effects on infant adiposity, associations between maternal and paternal body mass index (BMI) category (normal: ≤25 kg m(-2) , overweight: 25 - <30 kg m(-2) , obese: ≥30 kg m(-2) ) and infant BMI were compared in Fels Longitudinal Study participants. METHODS: A median of 9 serial weight and length measures from birth to 3.5 years were obtained from 912 European American children born in 1928-2008. Using multivariable mixed effects regression, contributions of maternal vs. paternal BMI status to infant BMI growth curves were evaluated. Cubic spline models also included parental covariates, infant sex, age and birth variables, and interactions with child's age. RESULTS: Infant BMI curves were significantly different across the three maternal BMI categories (Poverall < 0.0001), and offspring of obese mothers had greater mean BMI at birth and between 1.5 and 3.5 years than those of over- and normal weight mothers (P ≤ 0.02). Average differences between offspring of obese and normal weight mothers were similar at birth (0.8 kg m(-2) , P = 0.0009) and between 2 and 3.5 years (0.7-0.8 kg m(-2) , P < 0.0001). Infants of obese fathers also had BMI growth curves distinct from those of normal weight fathers (P = 0.02). Infant BMI was more strongly associated with maternal than paternal obesity overall (P < 0.0001); significant differences were observed at birth (1.11 kg m(-2) , P = 0.006) and from 2 to 3 years (0.62 kg m(-2) , P3 years = 0.02). CONCLUSION: At birth and in later infancy, maternal BMI has a stronger influence on BMI growth than paternal BMI, suggesting weight control in reproductive age women may be of particular benefit for preventing excess infant BMI.

Adiposity in children and adolescents: correlates and clinical consequences of fat stored in specific body depots.

The 2011 Pennington Biomedical Research Center's Scientific Symposium focused on adiposity in children and adolescents. The symposium was attended by 15 speakers and other invited experts. The specific objectives of the symposium were to (i) integrate the latest published and unpublished findings on the laboratory and clinical assessment of depot-specific adiposity in children and adolescents, (ii) understand the variation in depot-specific adiposity and related health outcomes associated with age, sex, maturation, ethnicity and other factors and (iii) identify opportunities for incorporating new markers of abdominal obesity into clinical practice guidelines for obesity in children and adolescents. This symposium provided an overview of important new advances in the field and identified directions for future research. The long-term goal of the symposium is to aid in the early identification of children and adolescents who are at increased health risk because of obesity and obesity-related conditions.

Age at menarche and risk of type 2 diabetes among African-American and white women in the Atherosclerosis Risk in Communities (ARIC) study.

AIMS/HYPOTHESIS: We examined race differences in the association between age at menarche and type 2 diabetes before and after adjustment for adiposity. METHODS: We analysed baseline and 9-year follow-up data from 8,491 women (n = 2,505 African-American, mean age 53.3 years; n = 5,986 white, mean age 54.0 years) in the Atherosclerosis Risk in Communities (ARIC) study. Stratifying by race, we used logistic regression to estimate the OR for prevalent diabetes at baseline, and Cox proportional hazard models to estimate the HR for incident diabetes over follow-up according to age at menarche category (8-11, 12, 13, 14 and 15-18 years). RESULTS: Adjusting for age and centre, we found that early age at menarche (8-11 vs 13 years) was associated with diabetes for white, but not African-American women in both the prevalent (white OR 1.72, 95% CI 1.32, 2.25; African-American OR 1.13, 95% CI 0.84, 1.51; interaction p = 0.043) and incident models (white HR 1.43, 95% CI 1.08, 1.89; African-American HR 1.20, 95% CI 0.87, 1.67; interaction p = 0.527). Adjustment for adiposity and lifestyle confounders attenuated associations for prevalent (white OR 1.41, 95% CI 1.05, 1.89; African-American OR 0.94, 95% CI 0.68, 1.30; interaction p = 0.093) and incident diabetes (white HR 1.22, 95% CI 0.92, 1.63; African-American HR 1.11, 95% CI 0.80, 1.56; interaction p = 0.554). CONCLUSIONS/INTERPRETATION: Early menarche was associated with type 2 diabetes in white women, and adulthood adiposity attenuated the relationship. We did not find a similar association in African-American women. Our findings suggest that there may be race/ethnic differences in the influence of developmental factors in the aetiology of type 2 diabetes, which merit further investigation.

Relationship of insulin, glucose, leptin, IL-6 and TNF-α in human breast milk with infant growth and body composition.

BACKGROUND: Numerous appetite, growth, obesity-related hormones and inflammatory factors are found in human breast-milk, but there is little evidence on their relationship with infant body composition. OBJECTVIE: The purpose of the present cross-sectional pilot study was to assess the cross-sectional associations of appetite-regulating hormones and growth factors (leptin, insulin and glucose) and inflammatory factors (interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α)) in human breast-milk with infant size, adiposity, and lean tissue at 1-month of age in healthy term infants. METHODS: Human breast-milk was collected from nineteen exclusively breast-feeding mothers using one full breast expression between 8:00 and 10:00 a.m. The milk was then mixed, aliquoted, stored at -80°C and then centrifuged to remove the milk fat, prior to analyses using commercially available immunoassay kits; milk analytes were natural log transformed prior to analysis. Infant body composition was assessed using a Lunar iDXA v11-30.062 scanner (Infant whole body analysis enCore 2007 software, GE, Fairfield, CT). RESULTS: Maternal pre-pregnancy BMI was positively associated with milk leptin concentration (P = 0.0027), and so maternal-BMI-adjusted Spearman correlations were examined between breast-milk analytes and infant growth and body composition variables. As previously reported, greater milk leptin was associated with lower BMIZ (BMI-for-age z-score based on WHO 2006 growth charts; r = -0.54, P = 0.03). Glucose was positively associated with relative weight (r = 0.6, P = 0.01), and both fat and lean mass (0.43-0.44, P < 0.10). Higher concentrations of milk insulin were associated with lower infant weight, relative weight, and lean mass (r = -0.49-0.58, P < 0.06). Higher milk IL-6 was associated with lower relative weight, weight gain, percent fat, and fat mass (r = -0.55-0.70, P < 0.03 for all), while higher TNF-α was associated with lower lean mass (r = -0.58, P = 0.05), but not measures of adiposity. CONCLUSIONS: These preliminary data suggest for the first time that in the first months of life, breast-milk concentrations of insulin, glucose, IL-6 and TNF-α, in addition to leptin, may be bioactive and differentially influence the accrual of fat and lean body mass.

Patterns of linear growth and skeletal maturation from birth to 18 years of age in overweight young adults.

OBJECTIVE: To estimate differences in skeletal maturity and stature from birth to age 18 years between individuals who are overweight vs normal weight in young adulthood. PATIENTS AND METHODS: Weight, length and height, and relative skeletal age (skeletal-chronological age) were assessed annually from birth to age 18 years in 521 subjects (255 women) in the Fels Longitudinal Study who were overweight or obese (body mass index (BMI) >25 kg m(-2), n=131) or normal weight (n=390) in young adulthood (18-30 years). Generalized estimating equations were used to test for skeletal maturity and stature differences by young adult BMI status. RESULTS: Differences in height increased during puberty, being significant for girls at ages 10 to 12 years, and for boys at ages 11 to 13 years (P-values<0.001), with overweight or obese adults being ∼3 cm taller at those ages than normal weight adults. These differences then diminished so that by age 18 years, overweight or obese adults were not significantly different in stature to their normal weight peers. Differences in skeletal maturity were similar, but more pervasive; overweight or obese adults were more skeletally advanced throughout childhood. Skeletal maturity differences peaked at chronological age 12 in boys and 14 in girls (P-values<0.001), with overweight or obese adults being ∼1 year more advanced than normal weight adults. CONCLUSIONS: This descriptive study is the first to track advanced skeletal maturity and linear growth acceleration throughout infancy, childhood and adolescence in individuals who become overweight, showing that differences occur primarily around the time of the pubertal growth spurt. Increased BMI in children on a path to becoming overweight adults precedes an advancement in skeletal development and subsequently tall stature during puberty. Further work is required to assess the predictive value of accelerated pubertal height growth for assessing obesity risk in a variety of populations.

Longitudinal changes in calcaneal quantitative ultrasound measures during childhood.

UNLABELLED: This longitudinal study examined how calcaneal quantitative ultrasound (QUS) measures change during childhood while taking into account skeletal maturation, body mass index (BMI), and physical activity. The study reported sex differences in QUS growth curves and an inverse relationship between BMI and speed of sound (SOS) measures. INTRODUCTION: The aim of this study was to examine how calcaneal QUS parameters change over time during childhood and to determine what factors influence these changes. METHODS: The study sample consisted of a total of 192 Caucasian children participating in the Fels Longitudinal Study. A total of 548 calcaneal broadband ultrasound attenuation (BUA) and SOS observations were obtained between the ages of 7.6 and 18 years. The best fitting growth curves were determined using statistical methods for linear mixed effect models. RESULTS: There are significant sex differences in the pattern of change in QUS parameters (p < 0.05). The relationship between QUS measures and skeletal age is best described by a cubic growth curve in boys and a linear pattern among girls. Boys experience their most rapid growth in BUA and SOS in early and late adolescence, while girls experience constant growth throughout childhood. Adiposity levels were significantly associated with the changes in SOS among boys (p < 0.001) and girls (p < 0.01), indicating that children with higher BMI are likely to have lower SOS over time compared to children with lower BMI. For girls, physical activity levels showed positive associations with changes in QUS measures (p < 0.05). CONCLUSION: This study documents significant sex differences in the pattern of change in QUS measures over childhood and adolescence. Our study also shows significant influences of adiposity and physical activity on the pattern of change in QUS measures during childhood.

Sleep disturbance in relation to health-related quality of life in adults: the Fels Longitudinal Study.

OBJECTIVE: Sleep disturbances are prevalent problems in the general population. Symptoms of insomnia can impact various physical and mental conditions. Furthermore, sleep disturbances may worsen the quality of life independently of co-occurring medical conditions. In this study, we examined the relationships between self-reported sleep disturbance symptoms and health-related quality of life measures in the Fels Longitudinal Study. DESIGN: Cross-sectional study. PARTICIPANTS: A total of 397 adults (175 men and 222 women) aged 40 years and older were included in the present study. MEASUREMENTS: Three self-reported sleep disturbance measures (difficulty falling asleep, nocturnal awakenings and maintaining sleep, and daytime tiredness) were collected between 2003 and 2006. Health-related quality of life measures were assessed using the Medical Outcomes Survey Short Form (SF)-36. Socio-demographic status (marital status, employment status, and education) and current medical conditions were collected from participants during study visits. RESULTS: Individuals who reported frequent sleep disturbances showed significantly worse quality of life on all SF-36 subscales examined. The odds ratio (OR) ranged from 1.71 to 18.32 based on symptoms of insomnia across seven SF-36 domains in analyses adjusted for significant covariates influencing quality of life. Participants with severe sleep disturbances (both sleep problems and daytime impairment) showed generally higher odds of reporting poor SF-36 scores (adjusted ORs; 5.88 - 17.09) compared to participants with no problems. CONCLUSION: Sleep disturbance is comprehensively and independently associated with poor health-related quality of life in middle-aged and older adults.

Validity of a new automated software program for visceral adipose tissue estimation.

INTRODUCTION: Given the considerable time and research cost of analyzing biomedical images to quantify adipose tissue volumes, automated image analysis methods are highly desirable. Hippo Fat is a new software program designed to automatically quantify adipose tissue areas from magnetic resonance images without user inputs. Hippo Fat has yet to be independently validated against commonly used image analysis software programs. OBJECTIVE: Our aim was to compare estimates of VAT (visceral adipose tissue) and SAT (subcutaneous adipose tissue) using the new Hippo Fat software against those from a widely used, validated, computer-assisted manual method (slice-O-matic version 4.2, Tomovision, Montreal, CA, USA) to assess its potential utility for large-scale studies. METHODS: A Siemens Magnetom Vision 1.5-T whole-body scanner and a T1-weighted fast-spin echo pulse sequence were used to collect multiple, contiguous axial images of the abdomen from a sample of 40 healthy adults (20 men) aged 18-77 years of age, with mean body mass index of 29 kg/m(2) (range=19-43 kg/m(2)). RESULTS: Hippo Fat provided estimates of VAT and SAT that were highly correlated with estimates using slice-O-matic (R (2)>0.9). Average VAT was 9.4% lower and average SAT was 3.7% higher using Hippo Fat compared to slice-O-matic; the overestimation of SAT tended to be greater among individuals with greater adiposity. Individual-level differences for VAT were also substantial; Hippo Fattrade mark gave estimates of VAT ranging from 1184 cm(3) less to 566 cm(3) more than estimates for the same person using slice-O-matic. CONCLUSION: Hippo Fat provides a rapid method of quantifying total VAT, although the method does not provide estimates that are interchangeable with slice-O-matic at either the group (mean) or individual level.