Weight at birth and all-cause mortality in adulthood

Review: Is rapid fat accumulation in early life associated with adverse later health outcomes?

This review discusses ways in which the maternal environment and placental function affect the birth weight and adult health outcomes of offspring. These maternal and placental factors have varying and sometimes opposing effects on birth weight, resulting in infants that are born small for gestational age (SGA), large for gestational age (LGA) or preterm. However, all these alterations in weight have similar effects on adult health, increasing the risk of obesity and its associated cardiovascular and metabolic disorders. While birth weight has been used as a marker for risk of adverse adult health, we propose that a common feature of all these scenarios - early accumulation of excess body fat - may be a better marker than birth weight alone. Furthermore, altered neonatal fat accumulation may be more closely related to the mechanism by which maternal environment and placental adaptation mediate effects on adult health. We suggest that more research should be focussed on early fat accretion, factors that promote fat accretion and if it can be avoided, and whether it would be beneficial to try to reduce fat accumulation in early life.

Recent hip fracture trends in Sweden and Denmark with age-period-cohort effects

This study used nationwide hip fracture data from Denmark and Sweden during 1987-2010 to examine effects of (birth) cohort and period. We found that time trends, cohort, and period effects were different in the two countries. Results also indicated that hip fracture rates may increase in the not so far future.

INTRODUCTION

The reasons for the downturn in hip fracture rates remain largely unclear but circumstances earlier in life seem important.

METHODS

We ascertained hip fractures in the populations ≥50 years in Denmark and Sweden in national discharge registers. Country- and sex-specific age-period-cohort (APC) effects during 1987-2010 were evaluated by log-likelihood estimates in Poisson regression models presented as incidence rate ratios (IRR).

RESULTS

There were 399,596 hip fractures in SE and 248,773 in DK. Age-standardized hip fracture rate was stable in SE men but decreased in SE women and in DK. Combined period + cohort effects were generally stronger in SE than DK and in women than men. IRR per period ranged from 1.05 to 1.30 in SE and 0.95 to 1.21 in DK. IRR per birth cohort ranged from 1.07 to 3.13 in SE and 0.77 to 1.67 in DK. Relative period effects decreased with successive period in SE and described a convex curve in DK. Relative cohort effects increased with successive birth cohort in both countries but with lower risks for DK women and men and SE women born around the 1930s (age 75-86 years today and responsible for most hip fractures) partly explaining the recent downturn. Men and women born thereafter however seem to have a higher hip fracture risk, and we expect a reversal of the present decline in rates, with increasing hip fracture rates in both Denmark and Sweden during the upcoming decade.

CONCLUSIONS

Time trends, cohort, and period effects were different in SE and DK. This may reflect differences in general health as evident in known differences in life expectancy, healthcare organization, and prevention such as use of anti-osteoporosis drugs. Analyses indicate that hip fracture rates may increase in the not so far future.

Validity of recalled v. recorded birth weight: a systematic review and meta-analysis

Low birth weight is associated with adverse health outcomes. If birth weight records are not available, studies may use recalled birth weight. It is unclear whether this is reliable. We performed a systematic review and meta-analysis of studies comparing recalled with recorded birth weights. We followed the Meta-Analyses of Observational Studies in Epidemiology (MOOSE) statement and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched MEDLINE, EMBASE and Cumulative Index to Nursing and Allied Health Literature (CINAHL) to May 2015. We included studies that reported recalled birth weight and recorded birth weight. We excluded studies investigating a clinical population. Two reviewers independently reviewed citations, extracted data, assessed risk of bias. Data were pooled in a random effects meta-analysis for correlation and mean difference. In total, 40 studies were eligible for qualitative synthesis (n=78,997 births from 78,196 parents). Agreement between recalled and recorded birth weight was high: pooled estimate of correlation in 23 samples from 19 studies (n=7406) was 0.90 [95% confidence interval (CI) 0.87–0.93]. The difference between recalled and recorded birth weight in 29 samples from 26 studies (n=29,293) was small [range −86–129 g; random effects estimate 1.4 g (95% CI −4.0–6.9 g)]. Studies were heterogeneous, with no evidence for an effect of time since birth, person reporting, recall bias, or birth order. In post-hoc subgroup analysis, recall was higher than recorded birth weight by 80 g (95% CI 57–103 g) in low and middle income countries. In conclusion, there is high agreement between recalled and recorded birth weight. If birth weight is recalled, it is suitable for use in epidemiological studies, at least in high income countries.

Prenatal, birth and early life predictors of sedentary behavior in young people: a systematic review

BACKGROUND

Our aim was to systematically summarize the evidence on whether prenatal, birth and early life factors up to 6 years of age predict sedentary behavior in young people (≤18 years).

METHODS

PRISMA guidelines were followed, and searches were conducted in PubMed, SPORTDiscus, EMBASE and Web of Science up to December 1, 2015. We included observational (non-intervention) and longitudinal studies, that reported data on the association between one or more of the potential predictors and objectively or subjectively measured sedentary behavior. Study quality was assessed using a formal checklist and data extraction was performed using standardized forms independently by two researchers.

RESULTS

More than 18,000 articles were screened, and 16 studies, examining 10 different predictors, were included. Study quality was variable (0.36-0.95). Two studies suggest that heritability and BMI in children aged 2-6 years were significant predictors of sedentary behavior later in life, while four and seven studies suggest no evidence for an association between gestational age, birth weight and sedentary behavior respectively. There was insufficient evidence whether other prenatal, birth and early life factors act as predictors of later sedentary behavior in young people.

CONCLUSION

The results suggest that heritability and early childhood BMI may predict sedentary behavior in young people. However, small number of studies included and methodological limitations, including subjective and poorly validated sedentary behavior assessment, limits the conclusions.

TRIAL REGISTRATION

The systematic review is registered in the International Prospective Register of Systematic Reviews, PROSPERO, 17.10.2014 ( CRD42014014156 ).

Birth characteristics and all-cause mortality: a sibling analysis using the Uppsala birth cohort multigenerational study

This paper investigates the association between perinatal health and all-cause mortality for specific age intervals, assessing the contribution of maternal socioeconomic characteristics and the presence of maternal-level confounding. Our study is based on a cohort of 12,564 singletons born between 1915 and 1929 at the Uppsala University Hospital. We fitted Cox regression models to estimate age-varying hazard ratios of all-cause mortality for absolute and relative birth weight and for gestational age. We found that associations with mortality vary by age and according to the measure under scrutiny, with effects being concentrated in infancy, childhood or early adult life. For example, the effect of low birth weight was greatest in the first year of life and then continued up to 44 years of age (HR between 2.82 and 1.51). These associations were confirmed in within-family analyses, which provided no evidence of residual confounding by maternal characteristics. Our findings support the interpretation that policies oriented towards improving population health should invest in birth outcomes and hence in maternal health.

Using an External Exposome Framework to Examine Pregnancy-Related Morbidities and Mortalities: Implications for Health Disparities Research

Objective: We have conducted a study to assess the role of environment on the burden of maternal morbidities and mortalities among women using an external exposome approach for the purpose of developing targeted public health interventions to decrease disparities. Methods: We identified counties in the 48 contiguous USA where observed low birthweight (LBW) rates were higher than expected during a five-year study period. The identification was conducted using a retrospective space-time analysis scan for statistically significant clusters with high or low rates by a Discrete Poisson Model. Results: We observed statistically significant associations of LBW rate with a set of predictive variables. However, in one of the two spatiotemporal models we discovered LBW to be associated with five predictive variables (teen birth rate, adult obesity, uninsured adults, physically unhealthy days, and percent of adults who smoke) in two counties situated in Alabama after adjusting for location changes. Counties with higher than expected LBW rates were similarly associated with two environmental variables (ozone and fine particulate matter). Conclusions: The county-level predictive measures of LBW offer new insights into spatiotemporal patterns relative to key contributory factors. An external framework provides a promising place-based approach for identifying “hotspots” with implications for designing targeted interventions and control measures to reduce and eliminate health disparities.

Comparison of birth weight between school health records and medical birth records in Denmark: determinants of discrepancies

OBJECTIVE

To compare reported birth weight (BW) information in school health records with BW from medical birth records, and to investigate if maternal and offspring characteristics were associated with any discrepancies.

DESIGN

Register-based cohort study.

SETTING

Denmark, 1973-1991.

PARTICIPANTS

The study was based on BW recorded in the Copenhagen School Health Records Register (CSHRR) and in The Medical Birth Register (MBR). The registers were linked via the Danish personal identification number.

PRIMARY AND SECONDARY OUTCOME MEASURES

Statistical comparisons of BW in the registers were performed using t tests, Pearson's correlation coefficients, Bland-Altman plots and κ coefficients. Odds of BW discrepancies >100 g were examined by logistic regressions.

RESULTS

The study population included 47,534 children. From 1973 to 1979 when BW was grouped in 500 g intervals in the MBR, mean BW differed significantly between the registers. During 1979-1991 when BW was recorded in 10 and 1 g intervals, mean BW did not significantly differ between the two registers. BW from both registers was highly correlated (0.93-0.97). Odds of a BW discrepancy significantly increased with parity, the child's age at recall and by marital status (children of married women had the highest odds).

CONCLUSIONS

Overall, BW information in school health records agreed very well with BW from medical birth records, suggesting that reports of BWs in school health records in Copenhagen, Denmark generally are valid.

A Genetically Informed Study of the Associations Between Maternal Age at Childbearing and Adverse Perinatal Outcomes

We examined associations of maternal age at childbearing (MAC) with gestational age and fetal growth (i.e., birth weight adjusting for gestational age), using two genetically informed designs (cousin and sibling comparisons) and data from two cohorts, a population-based Swedish sample and a nationally representative United States sample. We also conducted sensitivity analyses to test limitations of the designs. The findings were consistent across samples and suggested that, associations observed in the population between younger MAC and shorter gestational age were confounded by shared familial factors; however, associations of advanced MAC with shorter gestational age remained robust after accounting for shared familial factors. In contrast to the gestational age findings, neither early nor advanced MAC was associated with lower fetal growth after accounting for shared familial factors. Given certain assumptions, these findings provide support for a causal association between advanced MAC and shorter gestational age. The results also suggest that there are not causal associations between early MAC and shorter gestational age, between early MAC and lower fetal growth, and between advanced MAC and lower fetal growth.

Long-Term Survival of Individuals Born Small and Large for Gestational Age

Background

Little is known on long-term survival and causes of death among individuals born small or large for gestational age. This study investigates birth weight in relation to survival and causes of death over time.

Methods

A national cohort of 1.7 million live-born singletons in Denmark was followed during 1979–2011, using the Danish Civil Registration System, the Medical Birth Registry and the Cause of Death Registry. Cox proportional hazards were estimated for the impact of small (SGA) and large (LGA) gestation weight and mortality overall, by age group and birth cohort.

Results

Compared to normal weight children, SGA children were associated with increased risk of dying over time. Though most of the deaths occurred during the first year of life, the cumulative mortality risk was increased until 30 years of age. The hazard ratios [HR] for dying among SGA children ages <2 years were: 3.47 (95% CI, 3.30–3.64) and 1.06 (95% CI, 0.60–1.87) in 30 years and older. HR for dying among SGA adults (20–29 years) were: 1.20 (95% CI, 0.99–1.46) in years 1979–1982 and 1.61 (95% CI, 1.04–2.51) in years 1989–1994. The SGA born had increased risk of dying from infection, heart disease, respiratory disease, digestive disease, congenital malformation, perinatal conditions, and accidents, suicide, and homicide. Individuals born LGA were associated with decreased mortality risk, but with increased risk of dying from malignant neoplasm.

Conclusions

Survival has improved independently of birth weight the past 30 years. However, children born SGA remain at significantly increased risk of dying up till they turn 30 years of age. Individuals born LGA have lower mortality risk but only in the first two years of life.

Comparison of weight and length at birth of non-Roma and Roma newborn in Serbia

OBJECTIVES

Roma infants tend to be smaller and are diagnosed as SGA more often than non-Roma infants, suggesting that specific anthropometric norms for these infants may be useful. We aimed to construct population-based centile, gender-specific charts for birth weight and length for singleton Roma infants born from 35 to 42 weeks of gestation and to compare it with anthropometric data of non-Roma infants.

METHODS

We analyzed data on 27,602 non-Roma (53 % males) and 2235 Roma (51 % males) singleton live infants delivered from 2006 to 2012 in South East Serbia. The LMS method was used to estimate the birth weight and length centiles.

RESULTS

Roma infants were up to 12 % lighter and up to 4 % shorter than non-Roma infants. Estimated centile charts for Roma males and females were constructed showing the 3rd, 10th, 25th, 50th, 75th, 90th and 97th centiles.

CONCLUSIONS

We created the separate centile charts for Roma ethnic group. The sample size was sufficient to demonstrate differences in mean birth weights and lengths of at term infants born during the study period.

Low birthweight or rapid catch-up growth: which is more associated with cardiovascular disease and its risk factors in later life? A systematic review and cryptanalysis

BACKGROUND

The effects of birthweight (the Barker hypothesis) and growth trajectory in early life on the incidence of cardiovascular disease (CVD) and its risk factors in later life have been investigated in a number of studies.

OBJECTIVE

To undertake a systematic review and cryptanalysis of the association of low birthweight (LBW) and the postnatal growth trajectory with CVD and its risk factors.

METHODS

English-language publications in PubMed, ISI Web of Science and Scopus were searched. Initially, two independent reviewers identified relevant papers in several steps and the quality of papers was then determined by a validated quality-appraisal checklist.

RESULTS

By applying maximum sensitivity, 7259 paper were identified, 382 of which were duplicates and 1273 were considered to be relevant to the topic. Then, after title and abstract review, 628 irrelevant papers were excluded; 26 papers were added after reference-checking. Then, 250 other papers were deleted after full text review. Finally, 39 relevant papers remained and were entered into the systematic review. Overall, 79·6% of all CVD risk factors reported in primary studies of the rapid catch-up growth hypothesis were statistically significant, whereas the corresponding figure was 58·5% for the effects of LBW (Barker hypothesis).

CONCLUSIONS

This systematic review highlights the importance of low birthweight in increasing the risk of CVD and its risk factors in later life. The results support rapid postnatal catch-up growth of LBW neonates as a more important factor than LBW alone in CVD and its risk factors.

Association between birth weight and objectively measured sedentary time is mediated by central adiposity: data in 10,793 youth from the International Children's Accelerometry Database

BACKGROUND

Birth weight is an early correlate of disease later in life, and animal studies suggest that low birth weight is associated with reduced activity and increased sedentary time. Whether birth weight predicts later sedentary time in humans is uncertain.

OBJECTIVES

We examined the relation between birth weight and sedentary time in youth and examined whether this association was mediated by central adiposity.

DESIGN

We used pooled cross-sectional data from 8 observational studies conducted between 1997 and 2007 that consisted of 10,793 youth (boys: 47%) aged 6-18 y from the International Children's Accelerometry Database. Birth weight was measured in hospitals or maternally reported, sedentary time was assessed by using accelerometry (<100 counts/min), and abdominal adiposity (waist circumference) was measured according to WHO procedures. A mediation analysis with bootstrapping was used to analyze data.

RESULTS

The mean (±SD) time spent sedentary was 370 ± 91 min/d. Birth weight was positively associated with sedentary time (B = 4.04, P = 0.006) and waist circumference (B = 1.59, P < 0.001), whereas waist circumference was positively associated with sedentary time (B = 0.82, P < 0.001). Results of the mediation analysis showed a significant indirect effect of birth weight on sedentary time through waist circumference (B: 1.30; 95% bias-corrected CI: 0.94, 1.72), and when waist circumference was controlled for, the effect of birth weight on sedentary time was attenuated by 32% (B = 2.74, P = 0.06).

CONCLUSION

The association between birth weight and sedentary time appears partially mediated by central adiposity, suggesting that both birth weight and abdominal adiposity may be correlates of sedentary time in youth.

Early pregnancy maternal and fetal angiogenic factors and fetal and childhood growth: the Generation R Study

STUDY QUESTION

What are the effects of maternal and fetal soluble fms-like tyrosine kinase 1 (sFlt-1) and placental growth factor (PlGF) concentrations on fetal and childhood growth patterns?

SUMMARY ANSWER

An angiogenic profile that is characterized by both low early pregnancy maternal sFlt-1 and PlGF concentrations and higher sFlt-1 concentrations, lower PlGF concentrations or a higher sFlt-1:PlGF ratio in umbilical cord blood is associated with a reduced fetal and childhood growth.

WHAT IS KNOWN ALREADY

An imbalance in maternal and fetal sFlt-1 and PlGF concentrations has been suggested to affect pregnancy outcomes. However, their effects on longitudinal fetal and childhood growth remain largely unknown.

STUDY DESIGN, SIZE, DURATION

This study was performed in 5980 mothers and 4108 of their children, participating in the Generation R Study; a population-based prospective cohort study from fetal life onwards in Rotterdam, the Netherlands (2001-2005).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Blood samples were obtained from mothers in early and mid-pregnancy and from the umbilical vein at delivery. Fetal and childhood growth characteristics (weight and length) were measured repeatedly by ultrasound and physical examinations until the age of 6 years. We assessed the associations of maternal and fetal angiogenic factors with fetal and childhood growth using repeated measurement regression models. Logistic regression models were used to determine associations between angiogenic factors and small for gestational age at birth (SGA).

MAIN RESULTS AND THE ROLE OF CHANCE

Compared with early pregnancy maternal sFlt-1 concentrations in the lowest quintile, early pregnancy maternal sFlt-1 concentrations in the highest quintile were associated with a higher fetal weight growth resulting in a higher birthweight (difference in birthweight 0.33 standard deviation score (SDS); 95% Confidence Interval (CI) 0.25-0.41), a lower risk of SGA (Odds Ratio (OR) 0.36; 95% CI 0.27-0.48) and a subsequent higher weight growth until the age of 6 years. Early pregnancy maternal PlGF concentrations in the lowest quintile were associated with a reduced weight growth pattern resulting in a smaller birthweight (difference in birthweight -0.34 SDS; 95% CI -0.44, -0.25), an increased risk of SGA (OR 3.48; 95% CI 2.39-5.08) and a lower weight growth throughout childhood. An early pregnancy maternal sFlt-1:PlGF ratio in the highest quintile was associated with a higher fetal weight growth pattern from 30 weeks onwards, resulting in a higher weight at birth (difference in birthweight 0.09 SDS; P-value <0.05), which remained present until the age of 2 years. Newborns with higher umbilical cord sFlt-1 concentrations, lower PlGF concentrations or a higher sFlt-1:PlGF ratio showed a lower fetal and childhood weight growth from 30 weeks gestation onwards until the age of 6 years (P-value <0.05). Similar patterns were observed in relation to fetal and childhood length growth.

LIMITATIONS, REASONS FOR CAUTION

The study is an observational study. Therefore, no causal relationships can be established.

WIDER IMPLICATIONS OF THE FINDINGS

Both a maternal and fetal angiogenic imbalance may affect fetal and childhood growth. Changes in angiogenic profiles may be involved in the pathways linking fetal growth restriction with the long-term risk of vascular disease in adulthood.

STUDY FUNDING/COMPETING INTERESTS

The first phase of the Generation R Study is made possible by financial support from The Erasmus Medical Centre, Rotterdam, the Erasmus University Rotterdam, and the Netherlands Organization for Health Research and Development (ZonMw 21000074). V.W.V.J. received additional grants from the Netherlands Organization for Health Research and Development (ZonMw VIDI). M.I.B.-B. is financially supported by the Bo Hjelt foundation (grant 2009). The authors have no competing interests.

A high birth weight is associated with increased risk of type 2 diabetes and obesity

BACKGROUND

The association between low birth weight and adult disease is well known. Less is known on long-term effects of high birth weight.

OBJECTIVE

This study aims to investigate whether a high birth weight increases risk for adult metabolic disease.

METHODS

Swedish term single births, 1973-1982 (n = 759,999), were studied to age 27.5-37.5 years using Swedish national registers. Hazard ratios (HRs) were calculated in relation to birth weight for type 2 diabetes, obesity, hypertension and dyslipidaemia.

RESULTS

Men with birth weights between 2 and 3 standard deviation score (SDS) had a 1.9-fold increased risk (HR 1.91, 95% confidence interval [CI] 1.25-2.90) of type 2 diabetes, whereas those with birth weights above 3 SDS had a 5.4-fold increased risk (HR 5.44, 95% CI 2.70-10.96) compared to men with birth weights between -2 and 2 SDS. The corresponding HRs for women were 0.60 (95% CI 0.40-0.91) and 1.71 (95% CI 0.85-3.43) for birth weights 2-3 SDS and >3 SDS, respectively. Men with birth weights between 2 and 3 SDS had a 1.5-fold increased risk (HR 1.47, 95% CI 1.22-1.77) of obesity. The corresponding risk for women was 1.3-fold increased (HR 1.32, 95% CI 1.19-1.46). For men and women with birth weights above 3 SDS, the risks of adult obesity were higher, HR 2.46 (95% CI 1.63-3.71) and HR 1.85 (95% CI 1.44-2.37), respectively.

CONCLUSIONS

A high birth weight, particularly very high, increases the risk of type 2 diabetes in male young adults. The risk of obesity increases with increasing birth weight in both genders.

A possible role of aryl hydrocarbon receptor in spontaneous preterm birth

Preterm birth (PTB) is defined as birth before 37 weeks of gestation and is a leading cause of neonatal mortality and morbidity. To date, the etiology of spontaneous PTB (sPTB) remains unclear; however, intrauterine bacterial infection-induced inflammation is considered to be one of the major triggers. Aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor. Upon activation, AhR signaling mediates many biological processes. AhR is abundantly expressed in human placentas, primarily in trophoblasts, and several fetal organs and tissues. The activation of AhR signaling can modulate inflammatory responses via promoting production of pro-inflammatory cytokines by the placenta and fetal membranes. These cytokines could enhance expression and/or activity of cyclooxygenase-2 (COX2) in human trophoblasts and amniotic epithelia, which in turn stimulate synthesis and release of prostaglandins (PGs; e.g., PGE2 and PGF2α). Given the discovery of a number of natural and endogenous AhR ligands in human, we hypothesize that in a subset of patients with high AhR expression in placentas and fetal membranes, repeated exposure to these AhR ligands hyperactivates AhR, inducing hyperactivation of the cytokines/COX2/PGs pathway, resulting in myometrial contractions, ultimately leading to sPTB. We further hypothesize that hyperactivation of this AhR pathway can induce sPTB either directly or in synergy with the bacterial infection. Proof of this hypothesis may provide a novel mechanism underlying sPTB.

Sexual dimorphism in epigenomic responses of stem cells to extreme fetal growth

Extreme fetal growth is associated with increased susceptibility to a range of adult diseases through an unknown mechanism of cellular memory. We tested whether heritable epigenetic processes in long-lived CD34+ hematopoietic stem/progenitor cells (HSPCs) showed evidence for re-programming associated with the extremes of fetal growth. Here we show that both fetal growth restriction and over-growth are associated with global shifts towards DNA hypermethylation, targeting cis-regulatory elements in proximity to genes involved in glucose homeostasis and stem cell function. We find a sexually dimorphic response; intrauterine growth restriction (IUGR) is associated with substantially greater epigenetic dysregulation in males, whereas large for gestational age (LGA) growth predominantly affects females. The findings are consistent with extreme fetal growth interacting with variable fetal susceptibility to influence cellular aging and metabolic characteristics through epigenetic mechanisms, potentially generating biomarkers that could identify infants at higher risk for chronic disease later in life.

Birth weight and subsequent risk of cancer

BACKGROUND

We aimed to determine the association between self-reported birth weight and incident cancer in the Women's Health Initiative Observational Study cohort, a large multiethnic cohort of postmenopausal women.

METHODS

65,850 women reported their birth weight by category (<6 lbs, 6-7 lbs 15 oz, 8-9 lbs 15 oz, and ≥10 lbs). All self-reported, incident cancers were adjudicated by study staff. We used Cox proportional hazards regression to estimate crude and adjusted hazard ratios (aHR) for associations between birth weight and: (1) all cancer sites combined, (2) gynecologic cancers, and (3) several site-specific cancer sites.

RESULTS

After adjustments, birth weight was positively associated with the risk of lung cancer (p=0.01), and colon cancer (p=0.04). An inverse trend was observed between birth weight and risk for leukemia (p=0.04). A significant trend was not observed with breast cancer risk (p=0.67); however, women born weighing ≥10 lbs were less likely to develop breast cancer compared to women born between 6 lbs-7 lbs 15 oz (aHR 0.77, 95% CI 0.63, 0.94).

CONCLUSION

Birth weight category appears to be significantly associated with the risk of any postmenopausal incident cancer, though the direction of the association varies by cancer type.

Early-life nutritional programming of longevity

Available data from both experimental and epidemiological studies suggest that inadequate diet in early life can permanently change the structure and function of specific organs or homoeostatic pathways, thereby ‘programming’ the individual’s health status and longevity. Sufficient evidence has accumulated showing significant impact of epigenetic regulation mechanisms in nutritional programming phenomenon. The essential role of early-life diet in the development of aging-related chronic diseases is well established and described in many scientific publications. However, the programming effects on lifespan have not been extensively reviewed systematically. The aim of the review is to provide a summary of research findings and theoretical explanations that indicate that longevity can be influenced by early nutrition.

Birth weight, physical morbidity, and mortality: a population-based sibling-comparison study

Associations between low birth weight (≤2,500 g) and increased risk of mortality and morbidity provided the foundation for the "developmental origins of health and disease" hypothesis. Previous between-family studies could not control for unmeasured confounders. Therefore, we compared differentially exposed siblings to estimate the extent to which the associations were due to uncontrolled factors. Our population cohort included 3,291,773 persons born in Sweden from 1973 to 2008. Analyses controlled for gestational age, among other covariates, and considered birth weight as both an ordinal and a continuous variable. Outcomes included mortality after 1 year, cardiac-related death, hypertension, ischemic heart disease, pulmonary circulation problems, stroke, and type 2 diabetes mellitus. We fitted fixed-effects models to compare siblings and conducted sensitivity analyses to test alternative explanations. Across the population, the lower the birth weight, the greater the risk of mortality (e.g., cardiac-related death (low birth weight hazard ratio = 2.69, 95% confidence interval: 2.05, 3.53)) and morbidity (e.g., type 2 diabetes mellitus (low birth weight hazard ratio = 1.79, 95% confidence interval: 1.50, 2.14)) outcomes in comparison with normal birth weight. All associations were independent of shared familial confounders and measured covariates. Results emphasize the importance of birth weight as a risk factor for subsequent mortality and morbidity.

Prenatal exposure to methylmercury and LCPUFA in relation to birth weight

BACKGROUND

Epidemiologic studies have been inconclusive regarding the impact of coexposure to long chain polyunsaturated fatty acids (LCPUFA) and methylmercury (MeHg) from fish consumption during pregnancy on measures of fetal development.

OBJECTIVES

We evaluated the association between birth weight and prenatal maternal LCPUFA status and MeHg exposure in the Republic of Seychelles.

METHODS

We measured LCPUFA in maternal whole blood collected at 28 weeks of gestation and following delivery and MeHg in maternal hair obtained at delivery. There were 230 births with complete data on birth weight and covariates. Multiple linear regression models controlled for infant sex, gestational age, maternal age, smoking during pregnancy, intrapartum weight gain, prepregnancy body mass index, maternal socioeconomic status, parity, gestational diabetes, and alcohol use during pregnancy.

RESULTS

The average birth weight was 3252 g (range 1654-4450) and the average gestational age was 39 weeks (range 34-41). Prenatal MeHg exposure and maternal LCPUFA status were not associated with birth weight. Infant sex and length of gestation were the only predictors, with male sex and increased gestational age consistently associated with greater birth weight.

CONCLUSIONS

These findings do not support a relationship between prenatal exposure to LCPUFA and/or MeHg from fish consumption and birth weight.

High Bab Birth Weight Andof Hormone-Associated Cancer in Mothers: The Cancer–Cardiovascular Disease Dichotomy and its Possible Causes

The idea of intrauterine or fetal factors being the cause of several prevalent noninfectious diseases in adults has recently gained the status of an axiom. One of the most thoroughly studied predictors is birth weight (BW). Although many published studies point at relations between BW and later adult morbidity or mortality, much less attention is paid to associations between baby BW and maternal morbidity. Available data suggest a sort of dichotomy in these relationships. Thus, cardiovascular risk is higher in mothers of babies with a reduced BW, while cancer risk, mainly of the breast and some other hormone-dependent cancers, is often higher among mothers of babies with a large BW (newborn macrosomia). This review addresses possible causes and endocrine mechanisms of this topic and suggests a ‘particular’ and ‘general’ solution for arising controversy. Emphasis is placed on a probable competition between chronic diseases (mainly, between female hormone-related cancer and cardiovascular pathology) within the concept of multiple causes of death. These associations should be remembered while studying the relation between offspring BW and maternal predisposition to hormone-associated cancers and other noncommunicable diseases.

Epigenetics of gestational diabetes mellitus and offspring health: the time for action is in early stages of life

The epidemic increase of type 2 diabetes and obesity in developed countries cannot be explained by overnutrition, physical inactivity and/or genetic factors alone. Epidemiologic evidence suggests that an adverse intrauterine environment, in particular a shortage or excess of nutrients is associated with increased risks for many complex diseases later in life. An impressive example for the 'fetal origins of adult disease' is gestational diabetes mellitus which usually presents in 1% to >10% of third trimester pregnancies. Intrauterine hyperglycemia is not only associated with increased perinatal morbidity and mortality, but also with increased lifelong risks of the exposed offspring for obesity, metabolic, cardiovascular and malignant diseases. Accumulating evidence suggests that fetal overnutrition (and similarly undernutrition) lead to persistent epigenetic changes in developmentally important genes, influencing neuroendocrine functions, energy homeostasis and metabolism. The concept of fetal programming has important implications for reproductive medicine. Because during early development the epigenome is much more vulnerable to environmental cues than later in life, avoiding adverse environmental factors in the periconceptional and intrauterine period may be much more important for the prevention of adult disease than any (i.e. dietetic) measures in infants and adults. A successful pregnancy should not primarily be defined by the outcome at birth but also by the health status in later life.

Birth weight, growth and feeding pattern in early infancy predict overweight/obesity status at two years of age: a birth cohort study of Chinese infants

OBJECTIVES

To investigate the early determinants of overweight and obesity status at age two years.

METHODS

A total of 1098 healthy neonates (563 boys and 535 girls) were involved in this community-based prospective study in China. Data on body weight and length were collected at birth, the 3(rd) and 24(th) month. A self-administered questionnaire was used to collect data on social demography and feeding patterns of children, etc. Three multivariable logistic regression models were employed to make various comparisons of weight status, i.e., model 1 (obesity vs. non-obesity), model 2 (combined overweight and obesity vs. normal weight, and model 3 (obesity, overweight and normal weight).

RESULTS

Prevalences of overweight/obesity (95(th) >BMI ≥85(th) p and BMI ≥95(th) p, referring to WHO BMI standards) at 2 years of age are 15.8%/11.2% for boys and 12.9%/9.0% for girls, respectively. Being born with macrosomia (OR: 1.80-1.88), relatively greater BMI increment in the first 3 months (OR: 1.15-1.16) and bottle emptying by encouragement at age two (OR: 1.30-1.57) were found in all three models to be significant risk factors for higher BMI status at 2 years. Pre-pregnancy maternal BMI (OR: 1.09-1.12), paternal BMI (OR: 1.06), and mixed breastfeeding (OR: 1.54-1.57) or formula feeding (OR: 1.90-1.93) in the first month were identified as significant in models 2 and 3. Child-initiated bottle emptying at age two was observed to increase the risk of obesity by 1.31 times but only in model 1.

CONCLUSION

Fetal and early postnatal growth and feeding pattern appear to have significant impacts on early childhood overweight and obesity status independent of parental BMI. Policy-based and multidisciplinary approaches to promote breastfeeding and enhancement of feeding skills of care takers may be promising intervention strategies.

Association between diet during preadolescence and adolescence and risk for breast cancer during adulthood

It is increasingly evident that diet during preadolescence and adolescence has important consequences for breast cancer during adulthood. However, only a few epidemiologic studies have been conducted on the relationship between diet during preadolescence and adolescence, and cancer during adulthood. This situation is partly because of methodological challenges such as the long latency period, the complexity of breast cancer, the lack of validated diet assessment tools, and the large number of subjects that must be followed, all of which increase costs. In addition, funding opportunities are few for such studies. Results from the small number of epidemiologic studies are inconsistent, but evidence is emerging that specific aspects of the diet during preadolescence and adolescence are important. For example, during preadolescence and adolescence, severe calorie restriction with poor food quality, high total fat intake, and alcohol intake tend to increase risk, whereas high soy intake decreases risk. Research on preadolescent and adolescent diet is a paradigm shift in breast cancer investigations. This research paradigm has the potential to produce transformative knowledge to inform breast cancer prevention strategies through dietary intervention during preadolescence and adolescence, rather than later in life, as is current practice, when it is perhaps less effective. Methodological challenges that have plagued the field might now be overcome by leveraging several existing large-scale cohort studies in the U.S. and around the world to investigate the role of diet during preadolescence and adolescence in risk for adult breast cancer.

Is fetal macrosomia related to blood pressure among adolescents? A birth cohort study in China

Birth weight (BW) has effects on blood pressure (BP). In order to explore the effects of macrosomia on BP in childhood and in adolescence, a longitudinal cohort study was conducted in Wuxi, China. Subjects with BW ≥4000 g, born in 1993-1995, were the exposed group; the unexposed comparisons were matched by year of birth and sex of infant, with BW of 2500-4000 g. Follow-ups in 2005-6 and 2011-12 were conducted, and height, weight and BP were measured by trained doctors. Multi-mixed models in SAS were used to control for repeated measures to explore the effects of fetal macrosomia on BP. At the inception of the cohort, 1595 pairs of participants were recruited. At the end, 1112 in the exposed group and 1126 in the unexposed group finished both follow-ups. Among adolescents, mean (s.d.) of systolic BP (SBP) was 110.83 (9.43)  mm  Hg, which was statistically significantly higher than that in the unexposed group (mean ± s.d.: 109.33 ± 9.26)  mm  Hg (P=0.0002). After adjusting the repeated measures and birth year, sex, mother's occupation and delivery age, adding weight during pregnancy, hypertension during delivery, gestational age and parity, being a picky eater in childhood, the macrosomia group had higher SBP than the normal BW group; the parameter estimate value was 1.03 (s.e.=0.30). When BMI in childhood and BMI in adolescence were added in the multi-model, the estimated β was 0.71 (s.e.=0.29). No statistically significant effect of macrosomia was found on diastolic BP among adolescents in the multianalysis.

A Comparative Study of Population Health in the United States and Canada during the Neoliberal Era, 1980–2008

This article draws on the vast evidence that suggests, on one hand, that socioeconomic inequalities in health are present in every society in which they have been measured and, on the other hand, that the size of inequalities varies substantially across societies. We conduct a comparative case study of the United States and Canada to explore the role of neoliberalism as a force that has created inequalities in socioeconomic resources (and thus in health) in both societies and the roles of other societal forces (political, economic, and social) that have provided a buffer, thereby lessening socioeconomic inequalities or their effects on health. Our findings suggest that, from 1980 to 2008, while both the United States and Canada underwent significant neoliberal reforms, Canada showed more resilience in terms of health inequalities as a result of differences in: ( a) the degree of income inequality, itself resulting from differences in features of the labor market and tax and transfer policies, ( b) equality in the provision of social goods such as health care and education, and ( c) the extent of social cohesiveness across race/ethnic- and class-based groups. Our study suggests that further attention must be given to both causes and buffers of health inequalities.

Epigenetic basis for fetal origins of age-related disease

The current concept of fetal origins of adult diseases describes in utero programming, or adaptation to a spectrum of adverse environmental conditions that ultimately leads to increased susceptibility to age-related diseases (e.g., type 2 diabetes and cardiovascular disease) later in life. Although the precise mechanism of this biological memory remains unclear, mounting evidence suggests an epigenetic basis. The increased susceptibility to chronic disease and involvement of multiple organ systems that is observed is analogous to the decline in resistance to disease that is typical of normal aging. Although the cumulative environment over the course of a lifetime can induce increasing epigenetic dysregulation, we propose that adverse events that occur during early development can induce significant additional dysregulation of the epigenome. Here, we describe the current evidence for fetal origins of adult disease and the associated role of epigenetic dysregulation. In addition, we present a new perspective on the induction of epigenetic alterations in utero, which subsequently lead to an aging phenotype marked by increased susceptibility to age-related diseases.

Trends of preterm birth and low birth weight in Japan: a one hospital-based study

Background

The proportions of preterm birth (PTB, ie., delivered before 37 gestational weeks) and low birth weight (LBW, ie., birth weight less than 2500 g at delivery) have been rising in developed countries. We sought to examine the factors contributing to the rise in Japan, with particular focus on the effects of obstetric interventions.

Methods

We used a database maintained by one large regional hospital in Shizuoka, Japan. We restricted the analysis to mothers who delivered live singleton births from 1997 to 2010 (n = 19,221). We assessed the temporal trends in PTB and LBW, then divided the study period into four intervals and compared the proportions of PTB and LBW. We also compared the newborns’ outcomes between the intervals.

Results

PTB, in particular medically indicated PTB, increased considerably. The increase was largely explained by changes in caesarean sections. The neonatal outcomes did not worsen, and instead the Apgar scores and proportions requiring neonatal intensive care unit (NICU) admission improved. In particular, the risks of NICU admission in the interval from 2007 to 2010 were decreased among all births [odds ratio (OR): 0.84; 95% confidence interval (CI): 0.75, 0.95] and medically indicated births (OR: 0.44; 95% CI: 0.29, 0.68) compared with the interval from 1997 to 2000.

Conclusions

Despite the increases in PTB as well as LBW, the present study suggests benefits of obstetric interventions. Rather than simple categorization of PTB or LBW, indicators such as perinatal mortality or other outcomes may be more appropriate for evaluation of perinatal health in developed countries.

Maternal inflammatory bowel disease and offspring body size: a prospective cohort study

BACKGROUND

Maternal inflammatory bowel disease (IBD) may influence intrauterine growth and hence size at birth, but the consequences for offspring in later life remain uncertain. This study investigated the growth of children of mothers with Crohn's disease (CD) or ulcerative colitis (UC).

METHODS

The Danish National Birth Cohort, comprising 40,640 mother-child pairs with 7-year follow-up of children's height and weight, were linked to the Danish National Disease Register, whereby 50 mothers with CD and 147 mothers with UC were identified. Associations were tested by regression analyses, taking several covariates into account.

RESULTS

Children of mothers with IBD were significantly shorter at birth than children of unaffected mothers (adjusted; CD, difference in cm, -0.82; 95% confidence interval [CI], -1.39 to -0.25; UC, -0.41; 95% CI, -0.75 to -0.07) and they tended to be of lower birth weight (adjusted; CD, difference in grams, -119.7; 95% CI, -246.7 to 7.3; UC, -64.0; 95% CI, -138.7 to 10.7). However, during the first year of life children of IBD mothers reached similar body sizes as children of unaffected mothers. At the 7-year follow-up, girls, but not boys, of CD mothers tended to be overweight (adjusted odds ratio [OR], 2.47; 95% CI, 0.98-6.24) and had increased waist circumference (adjusted difference in cm, 3.48; 95% CI, 1.40-5.58) compared to the unaffected population.

CONCLUSIONS

The present study confirms that maternal history of IBD leads to decreased birth size in offspring. Reassuringly, body size in children of IBD mothers approached body size in children of unaffected mothers during childhood.

Epigenetic Contributions to the Relationship between Cancer and Dietary Intake of Nutrients, Bioactive Food Components, and Environmental Toxicants

Epigenetics is the study of heritable changes in gene expression that occur without a change in DNA sequence. Cancer is a multistep process derived from combinational crosstalk between genetic alterations and epigenetic influences through various environmental factors. The observation that epigenetic changes are reversible makes them an attractive target for cancer prevention. Until recently, there have been difficulties studying epigenetic mechanisms in interactions between dietary factors and environmental toxicants. The development of the field of cancer epigenetics during the past decade has been advanced rapidly by genome-wide technologies - which initially employed microarrays but increasingly are using high-throughput sequencing - which helped to improve the quality of the analysis, increase the capacity of sample throughput, and reduce the cost of assays. It is particularly true for applications of cancer epigenetics in epidemiologic studies that examine the relationship among diet, epigenetics, and cancer because of the issues of tissue heterogeneity, the often limiting amount of DNA samples, and the significant cost of the analyses. This review offers an overview of the state of the science in nutrition, environmental toxicants, epigenetics, and cancer to stimulate further exploration of this important and developing area of science. Additional epidemiologic research is needed to clarify the relationship between these complex epigenetic mechanisms and cancer.

Obesity research based on the Copenhagen School Health Records Register

INTRODUCTION

To summarise key findings from research performed using data from the Copenhagen School Health Records Register over the last 30 years with a main focus on obesity-related research. The register contains computerised anthropometric information on 372,636 schoolchildren from the capital city of Denmark. Additional information on the cohort members has been obtained via linkages with population studies and national registers.

RESEARCH TOPICS

Studies using data from the register have made important contributions in the areas of the aetiology of obesity, the development of the obesity epidemic, and the long-term health consequences of birth weight as well as body size and growth in childhood.

CONCLUSION

Research using this unique register is ongoing, and its contributions to the study of obesity as well as other topics will continue for years to come.

Racial residential segregation and low birth weight in Michigan's metropolitan areas

OBJECTIVES

We examined the influence of racial residential segregation, independent of neighborhood economic factors, on the overall and specific etiological risks of low birth weight.

METHODS

We geocoded all singleton births in Michigan metropolitan areas during 2000 to census tracts. We used hierarchical generalized linear models to investigate the association between low birth weight (< 2500 g) and neighborhood-level economic and racial segregation, controlling for individual and neighborhood characteristics. We analyzed competing risks of the 2 etiologies of low birth weight: intrauterine growth restriction and preterm birth.

RESULTS

Living in a Black segregated area was associated with increased odds (odds ratio [OR] = 1.15; 95% confidence interval [CI] = 1.03, 1.29; P < .05) of low birth weight after adjusting for individual- and tract-level measures. The analysis suggested that the association between low birth weight and racial segregation was attributable primarily to increased risk of intrauterine growth restriction (OR = 1.19; 95% CI = 1.03, 1.37; P < .05).

CONCLUSIONS

Odds of low birth weight are higher in racially segregated Black neighborhoods in Michigan's metropolitan areas, independent of economic factors. The association appears to operate through intrauterine growth restriction rather than preterm birth.

A Review of Lifetime Risk Factors for Mortality

This review was undertaken for the Faculty and Institute of Actuaries as part of their programme to encourage research collaborations between health researchers and actuaries in order to understand better the factors influencing mortality and longevity. The authors presented their findings in a number of linked sessions at the Edinburgh conference (Joining Forces on Mortality and Longevity) in October 2009 and contributed to this overview. The purpose is to review evidence for the impact on adult mortality of characteristics of the individual's lifetime socioeconomic or psychosocial environment or phenotype at the behavioural; multi-system (e.g. cognitive and physical function); or body system level (e.g. vascular and metabolic traits) that may be common risk factors for a number of major causes of death. This review shows there is growing evidence from large studies and systematic reviews that these individual characteristics, measured in pre-adult as well as the adult life, are associated with later mortality risk. The relative contribution of lifetime environment, genetic factors and chance, whether these contributions change with age, and the underlying social and biological pathways are still to be clarified. This review identifies areas where further life course research is warranted.

Inflammatory links between obesity and metabolic disease

The obesity epidemic has forced us to evaluate the role of inflammation in the health complications of obesity. This has led to a convergence of the fields of immunology and nutrient physiology and the understanding that they are inextricably linked. The reframing of obesity as an inflammatory condition has had a wide impact on our conceptualization of obesity-associated diseases. In this Review, we highlight the cellular and molecular mechanisms at play in the generation of obesity-induced inflammation. We also emphasize how defining the immune regulation in metabolic tissues has broadened the understanding of the diversity of inflammatory responses.

Birth weight, postnatal weight change, and risk for high blood pressure among chinese children

BACKGROUND

It is hypothesized that a physiological predisposition toward hypertension results from a combination of intrauterine growth restriction or overgrowth and excessive postnatal weight gain. Previous studies were conducted largely in Western countries however the hypothesis may also be relevant in developing countries where metabolic disorders are increasing.

OBJECTIVE

We investigated the association of birth weight and postnatal weight gain with hypertension among Chinese children.

METHODS

A population based study was conducted among 15 600 children aged 3 to 6 years from Tianjin, China. Weight was expressed as z scores. Postnatal weight gain was defined as changes in z scores from birth to 3 to younger than 4 years, 4 to younger than 5 years, and 5 to 6 years. Hypertension was defined as greater than the 90th percentile of either systolic or diastolic blood pressure. Logistic regression-derived odds ratios and 95% confidence intervals were generated to estimate the association between birth weight and postnatal weight gain with hypertension risk in childhood.

RESULTS

Birth weight was positively associated with childhood hypertension in boys and girls (odds ratios [95% confidence interval] comparing extreme quartiles [high versus low] were 5.67 [3.83-8.39] and 2.58 [3.83-8.39], respectively). Postnatal weight gain was positively associated with hypertension and the association did not significantly vary by birth size for gestational age.

CONCLUSIONS

Greater birth weight or postnatal weight gain was associated with increased childhood hypertension risk, suggesting that intrauterine growth and postnatal weight gain may have implications on health during childhood.

Angiogenic factors in maternal circulation and the risk of severe fetal growth restriction

Maternal angiogenic factors (placental growth factor, soluble fms-like tyrosine kinase 1 (Flt-1), and soluble endoglin) may be associated with fetal growth restriction, and the associations may differ according to stage of pregnancy. Among children born to pregnant women without preeclampsia in Norway between 1992 and 1994, 217 singletons with severe growth restriction (small for gestational age (SGA), <2.5th percentile) were compared with 378 singleton controls. For each angiogenic factor, SGA risk was related to concentrations in maternal serum collected in the first 2 trimesters, by using women with a serum concentration in the middle third at both samplings as reference. A low placental growth factor (lowest third) at both samplings was associated with high risk of SGA (odds ratio=3.8, 95% confidence interval: 1.6, 8.8). An increase from the lowest to the highest third of soluble Flt-1 was associated with high SGA risk (odds ratio=6.2, 95% confidence interval: 2.4, 16.1). Women with high soluble endoglin (highest third) at the second sampling had approximately a 3.5-fold increased risk of SGA. Low maternal soluble Flt-1 in early pregnancy followed by a strong subsequent increase in soluble Flt-1 and soluble endoglin was associated with a particularly high risk of severe fetal growth restriction.

High-protein diet in lactation leads to a sudden infant death-like syndrome in mice

Background

It is well accepted that reduced foetal growth and development resulting from maternal malnutrition are associated with a number of chronic conditions in later life. On the other hand such generation-transcending effects of over-nutrition and of high-protein consumption in pregnancy and lactation, a proven fact in all developed societies, are widely unknown. Thus, we intended to describe the generation-transcending effects of a high-protein diet, covering most relevant topics of human life like embryonic mortality, infant death, and physical health in later life.

Methods

Female mice received control food (21% protein) or were fed a high protein diet (42% protein) during mating. After fertilisation, females stayed on their respective diet until weaning. At birth, pups were put to foster mothers who were fed with standard food or with HP diet. After weaning, control diet was fed to all mice. All offspring were monitored up to 360 days after birth. We determined glucose-tolerance and measured cardiovascular parameters using a tip-catheter. Finally, abdominal fat amount was measured.

Results and Conclusions

We identified a worried impact of high-protein diet during pregnancy on dams' body weight gain, body weight of newborns, number of offspring, and also survival in later life. Even more important is the discovery that high-protein diet during lactation caused a more than eight-fold increase in offspring mortality. The observed higher newborn mortality during lactation is a hitherto non-described, unique link to the still incompletely understood human sudden infant death syndrome (SIDS). Thus, although offspring of lactating mothers on high-protein diet might have the advantage of lower abdominal fat within the second half of life, this benefit seems not to compensate the immense risk of an early sudden death during lactation. Our data may implicate that both pregnant women and lactating mothers should not follow classical high-protein diets.

Birthweight and mortality in adulthood: a systematic review and meta-analysis

BACKGROUND

Small birth size may be associated with increased risk of cardiovascular diseases (CVD), whereas large birth size may predict increased risk of obesity and some cancers. The net effect of birth size on long-term mortality has only been assessed in individual studies, with conflicting results.

METHODS

The Meta-analyses of Observational Studies in Epidemiology (MOOSE) guidelines for conducting and reporting meta-analysis of observational studies were followed. We retrieved 22 studies that assessed the association between birthweight and adult mortality from all causes, CVD or cancer. The studies were systematically reviewed and those reporting hazard ratios (HRs) and 95% confidence intervals (95% CIs) per kilogram (kg) increase in birthweight were included in generic inverse variance meta-analyses.

RESULTS

For all-cause mortality, 36,834 deaths were included and the results showed a 6% lower risk (adjusted HR = 0.94, 95% CI: 0.92-0.97) per kg higher birthweight for men and women combined. For cardiovascular mortality, the corresponding inverse association was stronger (HR = 0.88, 95% CI: 0.85-0.91). For cancer mortality, HR per kg higher birthweight was 1.13 (95% CI: 1.07-1.19) for men and 1.04 (95% CI: 0.98-1.10) for women (P(interaction) = 0.03). Residual confounding could not be eliminated, but is unlikely to account for the main findings.

CONCLUSION

These results show an inverse but moderate association of birthweight with adult mortality from all-causes and a stronger inverse association with cardiovascular mortality. For men, higher birthweight was strongly associated with increased risk of cancer deaths. The findings suggest that birthweight can be a useful indicator of processes that influence long-term health.

Birthweight centile charts for South Asian infants born in the UK

BACKGROUND

UK-born infants of South Asian ethnic origin are known to have lower birthweights than their White British counterparts. When plotted on currently used birthweight charts they can be misclassified as small for gestational age. Similarly, large for gestational age infants can be missed. This has important clinical implications in their management.

OBJECTIVE

To create birthweight centile charts for the UK-born South Asian infants to identify true small and large for gestational age infants.

METHODS

A retrospective cross-sectional analysis of infants born 1 January 2003 to 31 December 2006 was undertaken. The birthweights of the South Asian and White British infants were compared. The LMS method was used to construct centile charts for the South Asian infants.

RESULTS

24,274 White British and 7,190 South Asian infants were included in the analysis. Overall, the South Asian males were 9-15% lighter than the White British males and the South Asian females were 9-13% lighter than the White British females. At term, the median birthweight for South Asian males was 329 g lower than that for White British males and for South Asian females 295 g less than the White British females.

CONCLUSION

There are significant differences in the birthweights of White British and UK-born South Asian infants. Hence the standard birthweight centile charts which were designed using the birthweight data of White British infants appear to misclassify a proportion of South Asian infants. Use of ethnic specific birthweight charts would allow better detection of truly growth-restricted and macrosomic South Asian infants.

Birth weight, childhood body mass index and risk of coronary heart disease in adults: combined historical cohort studies

Background

Low birth weight and high childhood body mass index (BMI) is each associated with an increased risk of coronary heart disease (CHD) in adult life. We studied individual and combined associations of birth weight and childhood BMI with the risk of CHD in adulthood.

Methods/Principal Findings

Birth weight and BMI at age seven years were available in 216,771 Danish and Finnish individuals born 1924–1976. Linkage to national registers for hospitalization and causes of death identified 8,805 CHD events during up to 33 years of follow-up (median = 24 years) after age 25 years. Analyses were conducted with Cox regression based on restricted cubic splines. Using median birth weight of 3.4 kg as reference, a non-linear relation between birth weight and CHD was found. It was not significantly different between cohorts, or between men and women, nor was the association altered by childhood BMI. For birth weights below 3.4 kg, the risk of CHD increased linearly and reached 1.28 (95% confidence limits: 1.13 to 1.44) at 2 kg. Above 3.4 kg the association weakened, and from about 4 kg there was virtually no association. BMI at age seven years was strongly positively associated with the risk of CHD and the relation was not altered by birth weight. The excess risk in individuals with a birth weight of 2.5 kg and a BMI of 17.7 kg/m² at age seven years was 44% (95% CI: 30% to 59%) compared with individuals with median values of birth weight (3.4 kg) and BMI (15.3 kg/m²).

Conclusions/Significance

Birth weight and BMI at age seven years appeared independently associated with the risk of CHD in adulthood. From a public health perspective we suggest that particular attention should be paid to children with a birth weight below the average in combination with excess relative weight in childhood.

Child health research funding and policy: imperatives and investments for a healthier world

Although pediatric research enjoyed significant benefits during the National Institutes of Health (NIH) doubling era, the proportion of the NIH budget devoted to the pediatric-research portfolio has declined overall. In light of this declining support for pediatric biomedical research, the Federation of Pediatric Organizations held a topic symposium at the 2009 Pediatric Academic Societies annual meeting as a forum for discussion of the past and future states of funding, the rationale for directing public funds toward the understanding of child health and disease, and new programs and paradigms for promoting child health research. This report of the symposium is intended to disseminate more broadly the information presented and conclusions discussed to encourage those in the child health research community to exert influence with policy makers to increase the allocation of national funding for this underfunded area.