Relationship between birth weight and cardiovascular risk factors in Japanese young adults

Association between maternal hypothyroidism, baby birth weight, and adult cardiovascular disease risk: insights from ECG measurements

OBJECTIVES

Thyroid hormone (TH) deficiency during pregnancy may affect cardiovascular function in offspring rats. This study aimed to evaluate the effect of TH deficiency during gestation, on the electrocardiogram indices of young and middle-aged offspring of male rats.

METHODS

Eight female rats were equally divided into hypothyroid and control groups. The hypothyroid mothers received 0.025% 6-propyl-2-thiouracil (PTU) in drinking water throughout pregnancy, while control mothers consumed only tap water. Following birth, male rats from each group were observed for 4 months (young age) and 12 months (middle-aged). The group known as fetal hypothyroid (FH) consisted of rats born from hypothyroid mothers. The serum T4 and TSH concentrations from mothers and newborn male rats were assayed at the end of gestation. Lead II electrocardiogram (ECG) was recorded for 5 minutes using Power Lab, AD Instruments.

RESULTS

There was a significant rise in the P wave voltage in young FH rats, whereas, it was decreased in middle-aged control and FH rats. The voltage of QRS decreased and its duration increased in the young and middle-aged FH rats compared to the corresponding control groups. Duration and voltage of the T wave were significantly altered in the young and middle-aged FH groups. PR and QT intervals significantly increased in the young and middle-aged FH groups compared to their controls.

CONCLUSIONS

Maternal hypothyroidism affected the electrocardiogram indices of offspring rats, possibly signaling cardiovascular problems later in life.

Association Between Birth Weight and Prevalence of Cardiovascular Disease and Other Lifestyle-related Diseases Among the Japanese Population: The JPHC-NEXT Study

BACKGROUND

An association between birth weight and cardiovascular disease (CVD) in adulthood has been observed in many countries; however, only a few studies have been conducted in Asian populations.

METHODS

We used data from the baseline survey (2011-2016) of the Japan Public Health Center-based Prospective Study for the Next Generation Cohort, which included 114,105 participants aged 40-74 years. Adjusted prevalence ratios (aPRs) and 95% confidence intervals (CIs) were calculated from the prevalence of present and past histories of CVD and other lifestyle-related diseases, including hypertension, diabetes, hyperlipidemia, and gout, by birth weight, using Poisson regression.

RESULTS

The prevalence of CVD increased with lower birth weight, with the highest prevalence among those with birth weight under 1,500 grams (males 4.6%; females 1.7%) and the lowest one among those with birth weight at or over 4,000 g (males 3.7%: females 0.8%). Among 88,653 participants (41,156 males and 47,497 females) with complete data on possible confounders, birth weight under 1,500 g was associated with a higher prevalence of CVD (aPR 1.76; 95% CI, 1.37-2.26), hypertension (aPR 1.29; 95% CI, 1.17-1.42), and diabetes (aPR 1.53; 95% CI, 1.26-1.86) when a birth weight of 3,000-3,999 grams was used as the reference. Weaker associations were observed for birth weight of 1,500-2,499 grams and 2,500-2,999 grams, while no significant associations were observed for birth weight at or over 4,000 grams. The association between birth weight and the prevalence of hyperlipidemia was less profound, and no significant association was observed between birth weight and gout.

CONCLUSION

Lower birth weight was associated with a higher prevalence of CVD, hypertension, and diabetes in the Japanese population.

Metabolic adjustments in neonatal dwarf and normal-sized goat kids: Relationship between serum metabolites and body size

The relationship between body size and metabolism of goats remains poorly studied. The study evaluated the neonatal metabolic adjustments and elucidated the relationship between serum metabolites and body size in 39 single-born dwarf and normal-sized goat kids. Body weight, length and height of kids were recorded at birth and blood samples were collected from the dwarf and normal-sized (Red Sokoto and Sahel) goats on Days 0 (birth), 3, 10 and 20, postnatal. Also, the body mass index (BMI) was calculated and the concentration of metabolic markers was determined. Results revealed that values of BMI, body weight, length and height were lowest (P < 0.01) in the dwarf, followed by values in Red Sokoto kids, while the Sahel kids had the highest (P < 0.01) values. Conversely, the concentration of triglyceride at birth was highest (P < 0.05) in the dwarf, moderate in Red Sokoto and lowest in Sahel goats. Similarly, the Sahel goat kids had the lowest neonatal (P < 0.05) concentration of serum cholesterol. Neonatal concentrations of serum albumin and urea were higher in Sahel than Red Sokoto (P < 0.05) and the dwarf (P > 0.05) goats. Concentration of serum albumin was lower (P < 0.05) at birth, but significantly increased later, while values of serum urea concentration were higher (P < 0.05) at birth, but significantly decreased in subsequent postnatal days. Unlike the BMI, birth weight showed significant negative (P < 0.05) correlation with the concentration of most serum metabolites, especially triglyceride, which showed negative correlation at birth and in subsequent postnatal days. We concluded that dwarfism or small body size is associated with high serum triglyceride in single-born neonatal goats, and this is probably due to the accumulation of body energy reserve in the form of body fat to compensate for lower body tissue mass.

Precocious evaluation of cardiovascular risk and its correlation with perinatal condition

The cardiovascular disease is the main cause of worldwide death. This profile is potentialized by the increased severity of infections in people with obesity, type 2 diabetes and hypertension. Children and adolescents are target groups for the prevention of non-communicable diseases. The Developmental Origins of Health and Disease concept points that perinatal conditions are an important risk factor to development of non-communicable disease in adulthood. In this context, the present review identifies perinatal factor that induces precocious cardiovascular risk factors, related with cardiometabolic syndrome. The low or high birth weight and caesarean delivery are risk factors that induce increased occurrence of cardiovascular risk biomarkers in children and adolescents, while the breast feeding or feeding with breast milk from the birth until two years-old is a protector strategy. Evaluation of perinatal conditions associated with precocious identification of cardiovascular risk factors in children and adolescents is an efficient strategy to prevent and control cardiovascular mortality; through interventions, as lifestyle changes during vulnerable windows of development, able to set up the risk to cardiometabolic disease.

Physique at Birth and Cardiovascular Disease Risk Factors in Japanese Urban Residents: the KOBE Study

Aim: This study investigated the relationship between birth physique and cardiovascular risk factors in Japanese urban residents aged 40 years and more.

Methods: A self-administered questionnaire on birth physique was performed among 624 individuals (165 men and 459 women) who participated in the KOBE study. We examined whether self-reported birth physique and available recorded birth weights matched for 72 participants. Then the association between birth physique and risk factors for all participants was examined by gender. Body size at birth in the questionnaire (large, medium, small) was set as an exposure and laboratory values from the baseline survey (2010-2011) were used as outcomes.

Results: Mean (standard deviation) recorded birth weight of 72 participants was 3665 (318), 3051 (300), and 2653 (199) g, in the large, medium, and small group, respectively. In the analysis for all participants, odds ratio for having both hypertension and impaired glucose tolerance were significantly higher in the small versus large birth weight group, which was 7.42 (95% CI 1.75–31.50) for men and 4.44 (95% CI 1.14–17.30) for women after adjusting for age, body mass index, smoking/alcohol/exercise habits, and menstrual status in women. Similar results were observed in participants with recorded birth weight.

Conclusions: The present study indicates that individuals with small physique at birth might be at higher risk for hypertension and impaired glucose tolerance in middle age compared to those with large birth weight.

Birth Weight and Risk of Type 2 Diabetes Mellitus, Cardiovascular Disease, and Hypertension in Adults: A Meta-Analysis of 7 646 267 Participants From 135 Studies

Background Low birth weight has been associated with increased risk of type 2 diabetes mellitus, cardiovascular disease, and hypertension, but the risk at high birth weight levels remains uncertain. This systematic review and meta-analysis aimed to clarify the shape of associations between birth weight and aforementioned diseases in adults and assessed sex-specific risks. Methods and Results We systematically searched PubMed, EMBASE , and Web of Science for studies published between 1980 and October 2016. Studies of birth weight and type 2 diabetes mellitus (T2 DM ), cardiovascular disease ( CVD ), and hypertension were included. Random-effects models were used to derive the summary relative risks and corresponding 95% confidence intervals.We identified 49 studies with 4 053 367 participants assessing the association between birth weight and T2 DM , 33 studies with 5 949 477 participants for CVD , and 53 studies with 4 335 149 participants for hypertension and high blood pressure. Sex-specific binary analyses showed that only females had an increased risk of T2 DM and CVD at the upper tail of the birth weight distribution. While categorical analyses of 6 birth weight groups and dose-response analyses showed J-shaped associations of birth weight with T2 DM and CVD , the association was inverse with hypertension. The lowest risks for T2 DM , CVD , and hypertension were observed at 3.5 to 4.0, 4.0 to 4.5, and 4.0 to 4.5 kg, respectively. Conclusions These findings indicate that birth weight is associated with risk of T2 DM and CVD in a J-shaped manner and that this is more pronounced among females.

Deciphering the Role of the Non-Coding Genome in Regulating Gene-Diet Interactions

Protein encoding genes constitute a small fraction of mammalian genomes. In addition to the protein coding genes, there are other functional units within the genome that are transcribed, but not translated into protein, the so called non-coding RNAs. There are many types of non-coding RNAs that have been identified and shown to have important roles in regulating gene expression either at the transcriptional or post-transcriptional level. A number of recent studies have highlighted that dietary manipulation in mammals can influence the expression or function of a number of classes of non-coding RNAs that contribute to the protein translation machinery. The identification of protein translation as a common target for nutritional regulation underscores the need to investigate how this may mechanistically contribute to phenotypes and diseases that are modified by nutritional intervention. Finally, we describe the state of the art and the application of emerging ‘-omics’ technologies to address the regulation of protein translation in response to diet.

Association between Blood Pressure and Birth Weight among Rural South African Children: Ellisras Longitudinal Study

The aim of this cross-sectional study was to investigate the association between birth weight, underweight, and blood pressure (BP) among Ellisras rural children aged between 5 and 15 years. Data were collected from 528 respondents who participated in the Ellisras Longitudinal Study (ELS) and had their birth weight recorded on their health clinic card. Standard procedure was used to measure the anthropometric measurements and BP. Linear regression was used to assess BP, underweight variables, and birth weight. Logistic regression was used to assess the association of hypertension risks, low birth weight, and underweight. The association between birth weight and BP was not statistically significant. There was a significant (p < 0.05) association between mean BP and the sum of four skinfolds (β = 0.26, 95% CI 0.15-0.23) even after adjusting for age (β = 0.18, 95% CI 0.01-0.22). Hypertension was significantly associated with weight for age z-scores (OR = 5.13, 95% CI 1.89-13.92) even after adjusting for age and sex (OR = 5.26, 95% CI 1.93-14.34). BP was significantly associated with the sum of four skinfolds, but not birth weight. Hypertension was significantly associated with underweight. Longitudinal studies should confirm whether the changes in body weight we found can influence the risk of cardiovascular diseases.

Trends in perinatal mortality and its risk factors in Japan: Analysis of vital registration data, 1979-2010

As Japan has achieved one of the lowest perinatal mortality rates (PMR), our study aims to estimate trends in and risk factors for perinatal mortality among singleton births in Japan. We used Japanese vital registration data to assess trends in and risk factors for perinatal outcomes between 1979 and 2010. Birth and death registration data were merged. An autoregressive integrated moving average model was fitted separately by sex to the PMR and the proportion of stillbirths. A multilevel Poisson regression model was used to estimate risk factors for perinatal mortality. Between 1979 and 2010 there were 40,833,957 pregnancies and 355,193 perinatal deaths, the PMR decreased from 18.86 per 1,000 all births to 3.25 per 1,000 all births, and the proportion of stillbirths increased from 83.6% to 92.1%. Key risk factors for perinatal mortality were low or high birth weight, prematurity and post maturity, and being from poorer or unemployed families. A higher proportion of excess perinatal deaths could be averted by effective policies to prevent stillbirths and improved research into their interventions and risk factors. As the cost and challenge of maintaining perinatal mortality gains increases, policies need to be targeted towards higher risk groups and social determinants of health.

Sex differences in the developmental origins of cardiovascular disease

The Developmental Origins of Health and Disease (DOHaD) proposes that adverse events during early life program an increased risk for cardiovascular disease. Experimental models provide proof of concept but also indicate that insults during early life program sex differences in adult blood pressure and cardiovascular risk. This review will highlight the potential mechanisms that contribute to the etiology of sex differences in the developmental programming of cardiovascular disease.

Relationships between birth weight and serum cholesterol levels in healthy Japanese late adolescents

Poor growth in utero has been suggested to be associated with adverse levels of serum cholesterol concentrations in later life. In Asia, there have only been a limited number of studies examining the relationship between fetal status and serum lipids, especially in adolescents. The objective of this study was to examine the relationships between birth weight and serum high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol levels; adjusting for current physical status including percent body fat, physical activity and nutrient intake in healthy Japanese late adolescents. The data of 573 late adolescents with an average age of 17.6 (287 boys and 286 girls) who underwent physical examinations which included blood sampling and who had all the required data, were analyzed. Birth weight was obtained from their maternal and child health handbook. Multiple regression analysis showed that birth weight was positively associated with serum HDL in girls, independently of percent body fat or fat intake, when adjusted for current body height and weight. There were no associations between birth weight and serum HDL in boys, or serum LDL in either sex.

Lifetime growth and blood pressure in adolescence: Hong Kong's "Children of 1997" birth cohort

OBJECTIVES

Blood pressure tracks from adolescence to adulthood and is positively associated with low birth weight and faster infant growth. Most observations are from Western populations; it is unclear whether these are biologically based or contextually specific. We examined the associations of growth with blood pressure in adolescence.

METHODS

Multivariable partial least squares regression was used to assess the associations of growth to ~11 years with blood pressure at ~11 years in 5813 term births from Hong Kong's Children of 1997 birth cohort. Growth was considered as gender- and age-specific z-scores for birth weight, BMI, and length at 3 months; change in z-scores for BMI and height at 3 to 9 months, 9 to 36 months, 3 to 7 years, and 7 to 11 years; and BMI and height at 11 years.

RESULTS

Birth weight was weakly inversely associated with systolic blood pressure in girls -0.58 mm Hg 95% confidence interval -1.05 to -0.12 (boys -0.21, -0.71 to 0.30). Childhood growth, particularly linear growth at 7 to 11 years (girls: 1.27, 0.56 to 1.98; boys 2.11, 1.39 to 2.83), as well as current height (girls: 2.40, 2.04 to 2.76, boys: 2.65, 2.29 to 3.01) and BMI (girls: 2.72, 2.35 to 3.09, boys: 2.72, 2.09 to 3.36) were associated with higher systolic blood pressure. Diastolic blood pressure was also positively associated with current size.

CONCLUSIONS

In the first study to examine simultaneously the role of pre- and postnatal growth in adolescent blood pressure, the role of late childhood growth predominated.

Epidemiological studies of the developmental origins of adult health and disease in Japan: a pediatric perspective in present day Japan

The origins of adult disease are considered to relate to fetal undernutrition, and this concept is termed “developmental origins of adult health and disease” (DOHaD). Here, we describe several epidemiological studies performed in Japan and discuss whether DOHaD is applicable to children in present day Japan. In a study of healthy children and young adults, it was found that systolic blood pressure, total cholesterol and adiponectin were associated with birth weight. Hyperinsulinemia, high blood pressure, elevated transaminase levels and prevalence of metabolic syndrome in obese children were inversely correlated with birth weight and positively correlated with current weight and waist circumference. Birth weight was related to the development of type 2 diabetes in children. DOHaD is therefore considered to be applicable in Japan. The key considerations of DOHaD are the following two mismatches. The first mismatch pertains to growth and development in response to environmental influences, especially those of nutrition. The second mismatch pertains to the prenatal versus postnatal environment. We consider that the chance of children in present day Japan developing adult diseases is determined by the above mismatches. Pediatricians and schoolteachers should therefore understand the concept of DOHaD, so that they can educate both children and their families regarding an appropriate diet to reduce the likelihood of developing adult diseases in later life.

Lipid profiles in middle-aged men and women after famine exposure during gestation: the Dutch Hunger Winter Families Study

BACKGROUND

Many studies in humans have related birth weight to lipid profiles in adulthood. Fewer have estimated associations directly attributable to maternal nutrition during pregnancy.

OBJECTIVE

Our objective was to determine whether famine exposure during gestation is associated with a more atherogenic profile in adult offspring.

DESIGN

In 2003-2005, we studied 1) 359 singleton men and women born between January 1945 and March 1946 in clinics in Amsterdam, Rotterdam, and Leiden whose mothers were exposed to the famine during pregnancy; 2) 299 singletons born in the same 3 institutions during 1943 or 1947; and 3) 313 unexposed same-sex siblings of the above individuals. A lipid profile was obtained after an overnight fast.

RESULTS

Female offspring with prenatal famine exposure had a dyslipidemic pattern characterized by elevated total cholesterol (0.26 mmol/L; 95% CI: 0.07, 0.46; P = 0.007), triglycerides (0.17 mmol/L; 95% CI: 0.03, 0.31; P = 0.02), and LDL cholesterol (0.17 mmol/L; 95% CI: -0.01, 0.36; P = 0.06) compared with unexposed offspring. This pattern was not seen in men. The increases in total cholesterol and LDL cholesterol were independent of body mass index, waist circumference, and midthigh circumference. The increase in triglycerides was independent of midthigh circumference but was attenuated with control for either body mass index or waist circumference. There was no evidence for associations within specific gestational windows. No association was observed between prenatal famine exposure and HDL cholesterol in either sex.

CONCLUSION

In women, but not in men, aged approximately 58 y, we observed an association between prenatal undernutrition and elevated total cholesterol concentrations and triglycerides.

Lower birth weight is associated with higher resting heart rate during boyhood

There is substantial evidence that low birth weight is associated with the development of cardiovascular disease in adult life. Moreover, resting heart rate is a prognostic factor of cardiovascular morbidity and mortality. However, there are scarce data regarding the association between birth weight and resting heart rate in later life. Therefore, we investigated the association of anthropometric data at birth and hemodynamic indices including resting heart rate in Japanese boys. The data of 1,107 male students of a junior high school in Tokyo, Japan, who underwent a medical check-up in the year of admission to the school (12 or 13 years old) were used. Information on anthropometric data at birth based on "The Maternal and Child Health Handbook" was obtained from 573 students. From a standard 12-channel resting electrocardiogram, 8 cardiac cycles were used to estimate heart rate. Resting heart rate correlated positively with body mass index at the same age (r=0.100, p=0.017) and correlated negatively with birth weight (r=-0.102, p=0.015), height at birth (r=-0.125, p=0.003), and head circumference at birth (r=-0.095, p=0.025). The negative correlation of anthropometric data at birth with heart rate at the age of 12 or 13 was independent of body mass index at the same age. The mean value of resting heart rate at the age of 12 or 13 adjusted for body mass index at the same age was significantly higher in the lower tertile of birth weight than in the higher tertile of birth weight (81.7 vs. 78.5 beats/min, p=0.028). In conclusion, lower birth weight is associated with higher resting heart rate during boyhood, suggesting that elevated heart rate may be one mechanism linking small size at birth with the development of cardiovascular disease in future life.

Birth size and coronary heart disease risk score in young adulthood. The Atherosclerosis Risk in Young Adults (ARYA) study

Data of the Atherosclerosis Risk in Young Adults (ARYA) study were used to investigate the association between birth size and the absolute risk for coronary heart disease in healthy young adults. The cohort study comprises 750 (46.9% men) subjects born between 1970 and 1973. Birth characteristics were obtained from school health records. At young adulthood, blood pressure, anthropometry and fasting lipid levels were measured. Questionnaires were taken about smoking and diabetes. The young adult 10-year risk for coronary heart disease was calculated using the Framingham risk score. The overall 10-year risk for coronary heart disease was 1.6% (standard deviation (SD) 1.9), 3.0% (SD 1.9) in men and 0.3% (SD 0.2) in women. Using linear regression it was shown that a SD lower birth weight (=0.54 kg) was associated with 0.1% greater risk in the overall population (95% confidence interval (CI): -0.19, -0.004). Similarly, a lower ponderal index at birth was associated with an 0.11% higher risk (95% CI: -0.21, -0.002). These relations were stronger in men. Lower birth length was related with an increased risk in women (-0.02% risk/SD birth length; 95% CI: -0.04, 0.0001). These results suggest that small birth size is associated with an increased risk score for coronary artery disease in young adulthood.

Birth Weight and Adult Hypertension Cross-Sectional Study in a Japanese Workplace Population

BACKGROUND

Low birth weight has been associated with adult hypertension in several Western populations. This association needs to be evaluated in Japanese people.

METHODS AND RESULTS

A population-based cross-sectional study of 3,107 subjects (2,303 males and 804 females) aged 35-66 years was conducted. The participants responded to a questionnaire about their birth weights, blood pressure, medical history, parental history, and lifestyle factors. Hypertension was defined as systolic blood pressure > or =140 mmHg and/or diastolic blood pressure > or =90 mmHg and/or under treatment by anti-hypertensives. Multiple logistic regression analysis adjusted for age, sex, body mass index, parental history, and lifestyle revealed the adjusted odds ratios for hypertension were 1.26 (95% confidence interval: 0.88-1.80), 1.00 (reference), 0.89 (0.73-1.08) and 0.70 (0.49-1.00) in subjects in birth weight categories of <2,500 g, 2,500-<3,000 g, 3,000-<3,500 g, 3,500- g, respectively (p-value for trend =0.009). Furthermore, this inverse association was clearly pronounced in normal-weight subjects.

CONCLUSION

Low birth weight was independently associated with adult hypertension in the Japanese workplace population. Our results support the inverse association observed previously in Western populations and suggest that intrauterine environmental insults might lead to permanent changes in the metabolism and structure of the fetal organs influencing the regulation of blood pressure.

Developmental determinants of blood pressure in adults

Over the past 20 years a large and varied body of research has attempted to make the case for the developmental origins of elevated adult blood pressure (BP). Experimental animal research has identified plausible biological mechanisms through which fetal nutritional insufficiency may affect adult BP. The majority of human epidemiologic studies demonstrate an inverse association of birth weight (the most commonly used marker of fetal nutrition) with adult BP and higher risk of hypertension among individuals with lower weight at birth. The most adverse BP outcomes occur among individuals who were small at birth but relatively large as adults, a finding that suggests a role for postnatal growth. We critically review the literature on proposed mechanisms and epidemiologic evidence for developmental origins of adult BP and hypertension, considering associations with birth weight, maternal nutrition during pregnancy, child growth patterns, and infant feeding.

Sex differences in the association between birth weight and total cholesterol. A meta-analysis

PURPOSE

Determine whether a sex difference exists in the association between birth weight and total cholesterol later in life.

METHODS

Meta-analysis of within-study differences in regression coefficients of cholesterol on birth weight.

RESULTS

A total of 34 regression coefficients from 30 studies were included in the analyses; these provided data on 33,650 males and 23,129 females. There was evidence that the inverse association between birth weight and total cholesterol was stronger in males compared to females. The pooled within-study difference in age-adjusted regression coefficients was -0.03 mmol/l (-0.06, -0.01), p = 0.02 and the pooled within-study difference in age and body mass index adjusted regression coefficients was -0.04 mmol/l (-0.07, -0.02), p = 0.002. There was no evidence of heterogeneity in these meta-analyses (both p values > 0.6).

CONCLUSIONS

These results provide some evidence for a sex difference in the birth weight-total cholesterol association. This is consistent with studies of fetal growth which suggest that birth size reflects different biological processes for females and males. However, other very large studies are required to confirm this finding.

Low birth weight is associated with higher adult total cholesterol concentration in men: findings from an occupational cohort of 25,843 employees

BACKGROUND

The majority of studies investigating the association between birth weight and adult total cholesterol (TC) concentration have been small and underpowered: not surprisingly, the findings have been inconsistent. We aimed to determine whether birth weight predicted adult TC in a large sample population.

METHODS AND RESULTS

Between 1994 and 1996, 132,000 British Telecom employees undertook voluntary occupational health screening. Birth weight and lifestyle factors were self-reported; TC concentration and body size were measured by occupational health nurses. Complete measurements were available for 18,286 men and 7557 women (age range, 17 to 64 years). We found that sex and birth weight significantly interacted to predict adult TC (birth weight/sex interaction term, P=0.002). In men, lower birth weight was associated with higher adult TC levels (a -0.07 reduction in TC for each 1-kg increase in birth weight; 95% CI, -0.09 to -0.04 mmol/L; P<0.001), whereas no association was observed in women. Adjustment for potential confounding factors, including current body size and menopausal status, did not alter the findings. Analysis by SD score showed that in men, a 1-SD decrease in body mass index lowered TC concentration approximately 5-fold more than a 1-SD increase in birth weight.

CONCLUSIONS

This is the largest study to investigate the association between birth weight and TC and suggests that the association may be dependent on sex. The absence of an association in women was not explained by menopausal status. The influence of fetal environment on adult TC is small compared with the influence of adult adiposity.

A supply–demand model of fetal energy sufficiency predicts lipid profiles in male but not female Filipino adolescents

OBJECTIVE

To test the hypothesis that the balance between fetal nutritional demand and maternal nutritional supply during pregnancy will predict lipid profiles in offspring measured in adolescence.

SUBJECTS AND METHODS

A total of 296 male and 307 female Filipino offspring (aged 14-16 y) and mothers enrolled in a longitudinal birth cohort study (begun in 1983-84) had lipid profiles measured. Data on maternal height (as a proxy for offspring growth potential and thus fetal nutritional demand) and third trimester maternal arm fat area (as a proxy for maternal supply) were used to create four groups hypothesized to reflect a gradient of fetal energy sufficiency.

RESULTS

As fetal energy sufficiency increased among males, there was a decrease in total cholesterol (TC) (P<0.05 for trend), low-density lipoprotein cholesterol (LDL-C), and the ratios of TC/HDL-C cholesterol and LDL-C/HDL-C (all P<0.001), while HDL-C increased (P<0.05). Similar associations were identified when lipid levels were modeled as dichotomous 'high-risk' cut-points used in cardiovascular disease prevention in adolescents. These relationships were stronger, or only present, among offspring of mothers in the lower half of the third trimester energy intake distribution, and were independent of the child's current adiposity, dietary energy and fat intake, maturity, household income, and birth weight. In females, the supply-demand model did not predict any lipid outcome or clinical risk criteria.

CONCLUSIONS

Our findings in males support the hypothesis that the balance between fetal nutritional demand and maternal nutritional supply has implications for future lipid profiles. The lack of significant associations in females adds to mounting evidence for sex differences in lipid metabolism programming, and may reflect sex differences in fetal nutritional demand.

SPONSORSHIP

The National Science Foundation, the Mellon Foundation, the Nestle Foundation, and the Emory University Internationalization Program.

Birth weight and lipids in a national birth cohort study

OBJECTIVE

To investigate the association between birth weight and lipid levels in a 53-year-old birth cohort from England, Scotland, and Wales.

METHODS AND RESULTS

Lipid levels were obtained from nonfasting blood samples, collected at the most recent follow-up of the MRC National Survey of Health and Development, for 2559 men and women. Regression models indicated that in men, a 1-kg increase in birth weight was associated with a 0.13-mmol/L decrease (95% CI: -0.23, -0.01) in total cholesterol at age 53 years (P=0.03), compared with a 0.02-mmol/L (95% CI: -0.11, 0.15) increase in women and a 0.06-mmol/L (95% CI: -0.15, 0.02) decrease in men and women combined. Adjustment for current height and body mass index (BMI) in men reduced the size of the relationship, with height being responsible for the reduction. Adult height and height at 2 and 4 years were significantly associated with total cholesterol in men and in men and women combined. The negative association between total cholesterol and birth weight was strongest among men with high BMI at age 53 years (P=0.03 for test for interaction between birth weight and BMI). There was no significant association between birth weight and LDL or HDL cholesterol in men or women before adjustment, but there was a positive association with HDL in women. When both sexes were analyzed together, an association was seen after adjustment for current body size. No confounding of these findings with social class was observed in this study.

CONCLUSIONS

Our results suggest that the small effect of birth weight on lipid levels at age 53 years has a limited public health impact. The findings suggest that childhood height growth may be more important than prenatal growth.

Relationship between birthweight and blood lipid concentrations in later life: evidence from the existing literature

BACKGROUND

It has been suggested that there is a link between fetal growth and chronic diseases later in life. Several studies have shown a negative association between birthweight and cardiovascular diseases, as well as cardiovascular disease risk factors, such as blood pressure and type 2 diabetes. Far fewer studies have focused on the association between size at birth and blood lipid concentrations. We have conducted a qualitative assessment of the direction and consistency of the relationship between size at birth and blood lipid concentrations to see whether the suggested relationship between intrauterine growth and cardiovascular diseases is mediated by lipid metabolism.

METHODS

A literature search covering the period January 1966 to January 2003 was performed using Medline, Embase, and Web of Science. All papers written in English and reporting the relationship between size at birth and lipid levels in humans were assessed. Bibliographies were searched for further publications.

RESULTS

From an initial screen of 1198 references, 39 papers were included involving 28 578 individuals. There was no consistent relationship between size at birth and blood lipid levels; the one exception being triglyceride concentration, which showed statistically significant negative or U-shaped, but not positive, relationships with birthweight.

CONCLUSION

This review does not strongly support a link between birthweight and blood lipid levels in later life. However, the research in this area is limited and in order to make any definitive conclusions, longitudinal studies with sufficient power, data, and prospective follow-up are needed.

Timing is everything: a reconsideration of fetal growth velocity patterns identifies the importance of individual and sex differences

Fetal growth has been posited to follow a "timing hypothesis" sequence in which the second trimester favors a single growth velocity peak in body length and the third trimester accommodates a single growth velocity peak in weight accrual. To our knowledge, this proposition has never been tested with high-frequency longitudinal ultrasound data from normally growing human fetuses. The present study examined whether fetal growth in leg length had its peak velocity at or about 20-26 gestational weeks and declined subsequently and whether estimated fetal weight velocity was maximal at or about 33 weeks and declined subsequently; if the greatest acquisition of leg length occurred in the second trimester and weight in the third trimester; and if birth outcomes reflected these relationships. The data in this study included approximately weekly longitudinal ultrasound data collected from 44 maternal/fetal pairs in Brussels, Belgium. Diaphyseal lengths of the femur and tibia provided information on leg growth and estimated fetal weight was assessed from the biparietal and occipital-frontal head diameters and transverse and anterior-posterior diameters of the abdomen. Growth patterns were investigated from individual growth curves derived from daily growth velocity z-scores. Paired t-tests compared individuals' trimestral increments in leg length and fetal weight. Least-squares regression models employing the robust procedure for repeated measurements were used to test for relationships between trimester, size, growth rates, and birth outcome, controlling for day of measurement, sex, maternal smoking, and gestational age at birth. The normal fetuses in this study grew by pulsatile patterns of leg and estimated weight acquisition, not a single peak and decline process. Greater incremental growth in estimated fetal weight occurred during the second trimester and leg length in the third trimester. Individual and sex effects were significant in growth velocity patterns. Girls grew with greater synchrony between leg and weight growth and were accelerated by comparison with boys, with faster leg growth predicting lower ponderal index by the second trimester. Birth outcomes were sex-specific in timing effects and predictive variables. These results support the importance of sex-specific analyses, reemphasize the common notion that girls grow faster than boys, and direct attention to cross-talk between energy resources and growth.

Birth weight and blood cholesterol level: a study in adolescents and systematic review

OBJECTIVE

To examine the relationship between birth weight and blood total cholesterol (TC) and to compare its strength with that of the relationship between current body mass index and TC.

METHODS

1). Cross-sectional study of adolescents, with retrospective ascertainment of birth weight from birth records or parental recall; 2). systematic review of studies examining the relations between birth weight and cholesterol at all ages.

PARTICIPANTS

1). 1532 individuals (92% white, 55% male) in 10 British towns; 2). 28 studies with 32 observations showing the change in TC per 1 kg increase in birth weight-6 in infancy, 14 in adolescents, 12 in adults.

RESULTS

In the cross-sectional study, there was a weak inverse relation between birth weight and TC level (-.061 mmol/L fall in TC per kg increase in birth weight, 95% confidence interval -.131 to.008 mmol/L per kg) which was little affected by adjustment for current body size. The difference in TC corresponding to an interquartile range increase in birth weight (-.03 mmol/L) was approximately a quarter of that for an equivalent increase in body mass index (.11 mmol/L). In the systematic review, an inverse association between birth weight and TC of a similar size to that in the cross-sectional study was observed (-.048 mmol/L per kg, 95% confidence interval -.078 to -.018 mmol/L per kg) similar in strength at all ages.

CONCLUSION

The relation of fetal nutrition to TC appears to be weak and is probably of limited public health importance when compared with the effects of childhood obesity.

Lipid profiles in adolescent Filipinos: relation to birth weight and maternal energy status during pregnancy

BACKGROUND

The finding that persons with low birth weight have a higher cardiovascular disease (CVD) risk than do persons with higher birth weight remains poorly understood.

OBJECTIVE

We tested the hypothesis that maternal arm fat area (MAFA) in the third trimester of pregnancy and birth weight of offspring are inversely related to the offspring's risk of CVD.

DESIGN

In a 1-y birth cohort study (1983-1984), 296 male and 307 female offspring were followed up (1998-1999) to measure their lipid profiles. Participants came from randomly selected communities of Cebu, Philippines.

RESULTS

MAFA (log cm2) was positively associated (beta) with HDL cholesterol (0.12 log mg/dL; P < 0.01) and inversely associated with total cholesterol (-10.0 mg/dL; P < 0.10), LDL cholesterol (-13.1 mg/dL; P < 0.01), and the ratios of total to HDL cholesterol and LDL to HDL cholesterol (both P < 0.001) in males. These relations were independent of birth weight, present adiposity, energy and fat intakes, maturity, and income. Birth weight < or = 2.6 kg was associated with elevated LDL cholesterol (9.9 mg/dL; P < 0.01) and an elevated ratio of LDL to HDL cholesterol (0.22; P < 0.10) only in males. In females, MAFA related positively to total (15.5 mg/dL; P < 0.05) and LDL (11.9 mg/dL; P < 0.05) cholesterol.

CONCLUSIONS

In this Filipino population, mothers with low energy status during pregnancy gave birth to male offspring who had a high CVD risk in adolescence, as indicated by lipid profiles. The findings in females are less consistent with the fetal origins hypothesis and suggest sex differences in the relation between fetal nutrition and postnatal lipid metabolism.

Environmental pollution and the global burden of disease

Exposures to environmental pollution remain a major source of health risk throughout the world, though risks are generally higher in developing countries, where poverty, lack of investment in modern technology and weak environmental legislation combine to cause high pollution levels. Associations between environmental pollution and health outcome are, however, complex and often poorly characterized. Levels of exposure, for example, are often uncertain or unknown as a result of the lack of detailed monitoring and inevitable variations within any population group. Exposures may occur via a range of pathways and exposure processes. Individual pollutants may be implicated in a wide range of health effects, whereas few diseases are directly attributable to single pollutants. Long latency times, the effects of cumulative exposures, and multiple exposures to different pollutants which might act synergistically all create difficulties in unravelling associations between environmental pollution and health. Nevertheless, in recent years, several attempts have been made to assess the global burden of disease as a result of environmental pollution, either in terms of mortality or disability-adjusted life years (DALYs). About 8-9% of the total disease burden may be attributed to pollution, but considerably more in developing countries. Unsafe water, poor sanitation and poor hygiene are seen to be the major sources of exposure, along with indoor air pollution.

Low birth weight contributes to the excess prevalence of end-stage renal disease in African Americans

The risk of hypertension and related target organ damage is much greater in African Americans than in Caucasians. The risk of hypertensive end-stage renal disease is approximately five-fold higher in African Americans. Many studies have shown that low birth weight is strongly associated with increased risk of hypertension, stroke, and myocardial infarction. However, until recently the relationship between birth weight and hypertension-related diseases was not clearly established in African Americans. Moreover, it was also unclear if low birth weight in humans heightened the risk for end-stage renal disease. This is a critical gap in the literature, since low birth weight occurs at twice the rate in African Americans as among Caucasians. We identified a significant relationship between end-stage renal disease and low birth weight in both African Americans and Caucasians. Given the higher rates of low birth weight in African Americans, differences in fetal development may, therefore, contribute to the racial disparity in end-stage renal disease. Continued study of the biological factors linking early development with later risk of hypertension-related diseases is important and may shed light on racial disparities in health outcomes. (c)2001 by Le Jacq Communications, Inc.