Birth Weight,Adulthood BMI,and Subsequent Weight Gain in Relation to Leptin Levels in Swedish Women

LISSNER, LAUREN, CECILIA KARLSSON, ANNA KARIN LINDROOS, LARS SJOSTROM, BJORN CARLSSON, LENA CARLSSON, AND CALLE BENGTSSON. Birth weight, adulthood BMI, and subsequent weight gain in relation to leptin levels in Swedish women. Obes Res. Objective Leptin seems to be involved in the regulation of energy balance, although little is known about the epidemiology of leptin with respect to prediction of weight gain and incidence of obesity-related diseases. The dual aim of this study is to document characteristics of leptin after long-term storage, and to describe its relation to body weight, from birth to old age, in an ongoing prospective study. Research Methods and Procedures A population-based sample of Swedish women was first examined at the ages of 38 to 60 and re-examined 24 years later. This study used 1358 frozen serum samples that had been stored 29 years for analysis of leptin concentrations and their relation to body weight history. Results Leptin values obtained from stored samples showed the same correlation with relative weight as that seen in a contemporary sample with similar demographic characteristics. Lower self-reported birth weight was associated with higher leptin levels in adulthood (p = 0.01), controlling for age and adult BMI. Prospective analyses revealed that high leptin in 38 to 46-year-olds predicted subsequent long-term weight gain (p = 0.003), although no significant associations were seen in women initially aged 50 or older. Discussion: It is feasible to use frozen serum for studying leptin in relation to obesity and related developments many years later. High leptin level was a risk factor for subsequent weight gain in 38- and 46-year-old women. Retrospective analyses involving birth weight suggest that leptin resistance in adulthood might have fetal origins.     

Polymorphisms in FTO and MAF Genes and Birth Weight,BMI, Ponderal Index,Weight Gain in a Large Cohort of Infants with a Birth Weight below 1500 Grams

Background

The FTO gene, located on chromosome 16q12.2, and the MAF gene, located on chromosome 16q22-23, were identified as genes harboring common variants with an impact on obesity predisposition. We studied the association of common variants with birth weight, gain of body weight, body mass index (BMI), Ponderal index and relevant neonatal outcomes in a large German cohort of infants with a birth weight below 1500 grams.

Methods

The single nucleotide polymorphisms rs9939609 (FTO gene) and rs1424233 (MAF gene) were genotyped using allelic discrimination assays in a prospective multicenter cohort study conducted in 15 neonatal intensive care units in Germany from September 2003 until January 2008. DNA samples were extracted from buccal swabs according to standard protocols.

Results

1946 infants were successfully genotyped at FTO and 2149 infants at MAF. Allele frequencies were not significantly different from other European cohorts. The polymorphisms were in Hardy-Weinberg equilibrium. The polymorphisms did not show associations with birth weight, BMI and Ponderal Index at discharge, and weight gain, neither testing for a dominant, additive nor for a recessive model.

Discussion

Since an association of the polymorphisms with weight gain has been demonstrated in multiple populations, the lack of association in a population of preterm infants with regular tube feeding after birth and highly controlled feeding volumes provides evidence for the hypothesis that these polymorphisms affect food intake behavior and hunger rather than metabolism and energy consumption.     

Birth Weight Reference Percentiles for Chinese

Objective

To develop a reference of population-based gestational age-specific birth weight percentiles for contemporary Chinese.

Methods

Birth weight data was collected by the China National Population-based Birth Defects Surveillance System. A total of 1,105,214 live singleton births aged ≥28 weeks of gestation without birth defects during 2006–2010 were included. The lambda-mu-sigma method was utilized to generate percentiles and curves.

Results

Gestational age-specific birth weight percentiles for male and female infants were constructed separately. Significant differences were observed between the current reference and other references developed for Chinese or non-Chinese infants.

Conclusion

There have been moderate increases in birth weight percentiles for Chinese infants of both sexes and most gestational ages since 1980s, suggesting the importance of utilizing an updated national reference for both clinical and research purposes.     

Familial Trends in Low Birth Weight

The reproductive performance of sisters and sisters-in-law of 185 women who had delivered “light-for-dates” and “premature expulsion” low birth weight infants was studied. Percentile birth weights were compared taking into account length of gestation, fetal sex, and the height, weight, parity, and smoking habits of the mother. Sisters of women who had delivered light-for-dates babies had lighter babies than the general population, their sisters-in-law, or the sisters of women in the premature expulsion group. These other groups, however, had the expected distribution of percentile birth weights. Data on familial trends in smoking habits and unknown gestation are also presented. The results are consistent with the theory that the mother''s own intrauterine experience affects her reproductive performance but could also be explained by shared family learning experience of as yet unidentified microsocial factors related to pregnancy performance.     

大熊猫出生体质量分类的初步探究

以成都大熊猫繁育研究基地的192只大熊猫Ailuropoda melanoleuca活体幼仔为研究对象,分析大熊猫出生体质量的统计学分布特点.结果显示,大熊猫出生体质量主要分布在[100,210),且处于[100,110)和[200,210)区间的个体频率也较高,而出生体质量低于60 g的幼仔个体极少;因此,根据大熊猫...     

Low Birth Weight and Normal Birth Weight Newborns of Kolkata, India: Comparison of Some Maternal Risk Factors

This study compared several maternal risk factors of low birth weight (LBW) between 204 normal birth weight (NBW) and 133 LBW newborns from Kolkata, India. Based on their birth weight (BW), newborns were classified as LBW (BW < 2.5 kg) and NBW (BW ≥ 2.5 kg). Results revealed that means for maternal age (MA, p < 0.05), gestational age (GA, p < 0.01), hemoglobin (Hb) concentration (p < 0.05), and per capita daily income (PCDI, p < 0.05) were significantly higher among mothers of NBW. Correlation analyses revealed that MA (r = 0.119, p < 0.05), GA (r = 0.583, p < 0.01), PCDI (r = 0.118, p < 0.05), and Hb (r = 0.138, p < 0.05) were significantly positively correlated with BW; PCDI was also significantly positively correlated (r = 0.142, p < 0.01) with Hb. Stepwise regression analyses with BW as the dependent variable revealed that GA (t = 7.915, p < 0.001) and Hb (t = 2.057, p < 0.05) were the most important predictive variables. The effect of Hb, independent of GA, was statistically significant (change in F = 4.231, p < 0.05). Because GA is not modifiable in pregnant women, there is a need to increase Hb levels among pregnant mothers. Most importantly, appropriately targeted preventive strategies, including iron supplementation, need to be implemented for health promotion.     

Maternal Determinants of Birth Weight in Northern Ghana

Objectives

Weight at birth is usually considered as an indicator of the health status of a given society. As a result this study was designed to investigate the association between birth weight and maternal factors such as gestational weight gain, pre—pregnancy BMI and socio—economic status in Northern Ghana.

Methods

The study was a facility-based cross-sectional survey conducted in two districts in the Northern region of Ghana. These districts were purposively sampled to represent a mix of urban, peri—urban and rural population. The current study included 419 mother-infant pairs who delivered at term (37–42 weeks). Mother’s height, pre-pregnancy weight and weight changes were generated from the antenatal records. Questionnaires were administered to establish socio-economic and demographic information of respondents. Maternal factors associated with birth weight were examined using multiple and univariate regressions.

Results

The mothers were generally well nourished before conception (Underweight 3.82%, Normal 57.76%, Overweight 25.06% and Obesity 13.37%) but approximately half of them could not gain adequate weight according to Institute of Medicine recommendations (Low weight gain 49.64%, Adequate weight gain 42.96% and Excessive weight gain 7.40%). Infants whose mothers had excess weight gain were 431g (95% CI 18–444) heavier compared to those whose mothers gained normal weight, while those whose mothers gained less were 479g (95% CI -682– (-276) lighter. Infants of mothers who were overweight and obese before conception were 246g (95% CI 87–405) and 595g (95% CI 375–815) respectively heavier than those of normal mothers, whereas those whose mothers were underweight were 305g (95% CI -565 –(-44) lighter. The mean birth weight observed was 2.98 ± 0.68 kg.

Conclusion

Our findings show that pre-pregnancy body mass index and weight gain during pregnancy influence birth weight. Therefore, emphasis should be placed on counseling and assisting pregnant women to stay within the recommended weight gain ranges.     

Intergenerational Predictors of Birth Weight in the Philippines: Correlations with Mother's and Father's Birth Weight and Test of Maternal Constraint

Background

Birth weight (BW) predicts many health outcomes, but the relative contributions of genes and environmental factors to BW remain uncertain. Some studies report stronger mother-offspring than father-offspring BW correlations, with attenuated father-offspring BW correlations when the mother is stunted. These findings have been interpreted as evidence that maternal genetic or environmental factors play an important role in determining birth size, with small maternal size constraining paternal genetic contributions to offspring BW. Here we evaluate mother-offspring and father-offspring birth weight (BW) associations and evaluate whether maternal stunting constrains genetic contributions to offspring birth size.

Methods/Principal Findings

Data include BW of offspring (n = 1,101) born to female members (n = 382) and spouses of male members (n = 275) of a birth cohort (born 1983–84) in Metropolitan Cebu, Philippines. Regression was used to relate parental and offspring BW adjusting for confounders. Resampling testing was used to evaluate whether false paternity could explain any evidence for excess matrilineal inheritance. In a pooled model adjusting for maternal height and confounders, parental BW was a borderline-significantly stronger predictor of offspring BW in mothers compared to fathers (sex of parent interaction p = 0.068). In separate multivariate models, each kg in mother’s and father’s BW predicted a 271±53 g (p<0.00001) and 132±55 g (p = 0.017) increase in offspring BW, respectively. Resampling statistics suggested that false paternity rates of >25% and likely 50% would be needed to explain these differences. There was no interaction between maternal stature and maternal BW (interaction p = 0.520) or paternal BW (p = 0.545).

Conclusions/Significance

Each kg change in mother’s BW predicted twice the change in offspring BW as predicted by a change in father’s BW, consistent with an intergenerational maternal effect on offspring BW. Evidence for excess matrilineal BW heritability at all levels of maternal stature points to indirect genetic, mitochondrial, or epigenetic maternal contributions to offspring fetal growth.     

Weight Loss Surgery Eligibility According to Various BMI Criteria Among Adolescents

A BMI cutoff point at the 99th percentile for age and gender or at 40 kg/m² has been suggested for more aggressive treatment of adolescent obesity. The main objective of this study was to determine the proportion of adolescents eligible for weight loss surgery (WLS) based on various BMI cutoff points. Data was extracted from the electronic medical record database of an urban pediatric ambulatory care center over 4 years. National data were used to calculate BMI percentiles (Centers for Disease Control and Prevention (CDC), 2000). Eligibility for WLS was based on a BMI percentile criterion (≥99th percentile) or the adult WLS cutoff point (≥40 kg/m²). The sample consisted of 3,220 adolescents aged 12–17.9 years, of which 53% were female, 55% were of black race, and 17% of Hispanic ethnicity. Overall, 88 (3%) adolescents had a BMI ≥40 kg/m² and 236 (7%) had a BMI ≥99th percentile (P < 0.001). All adolescents with BMI ≥40 kg/m² had a BMI ≥99th percentile. A total of 159/2,007 (8%) of 12–14.9‐year olds had a BMI ≥99th percentile compared with 77/1,213 (6%) 15–17.9‐year olds (P = 0.10), whereas 43/2,007 (2%) of 12–14.9‐year olds had a BMI ≥40 kg/m² compared with 45/1,213 (4%) 15–17.9‐year olds (P = 0.003). In summary, a relatively large proportion of adolescents from a diverse urban population would qualify for WLS based on the percentile criterion. Fewer adolescents would be eligible based on the adult WLS criterion, and younger adolescents would be less likely to be eligible for WLS than older adolescents.     

The Association between Weight Perception and BMI among High School Students

Objective: To assess the association between weight perception and BMI among a large, diverse sample of adolescents. This study used both measured and self‐reported height and weight to calculate BMI. Research Methods and Procedures: A convenience sample of students (n = 2032) in grades 9 through 12 completed a questionnaire assessing demographic characteristics, self‐reported height and weight, and body weight perception. These students were then weighed and had their height measured using a standard protocol. Results: Using BMI calculated from measured height and weight, 1.5% of students were classified as underweight or at risk for underweight, 51.2% of students were normal weight, and 47.4% were overweight or at risk for overweight. Among this same sample of students, however, 34.8% perceived themselves as underweight, 42.9% perceived themselves as about the right weight, and 22.3% perceived themselves as overweight. Even when using BMI calculated from self‐reported height and weight, >20% of students who were overweight or at risk for overweight perceived themselves as underweight. Discussion: Because perception of overweight is a key determinant of adolescent nutritional habits and weight management, many students who are overweight or at risk for overweight but who do not perceive themselves as such are unlikely to engage in weight control practices. Increasing awareness of medical definitions of overweight might improve accuracy of weight perceptions and lead to healthier eating and increased physical activity.