Cognitive and motor outcomes in children born low birth weight: a systematic review and meta-analysis of studies from South Asia

National and subnational trends of birthweight in Peru: Pooled analysis of 2,927,761 births between 2012 and 2019 from the national birth registry

Background

National and subnational characterization of birthweight profiles lacks in low- and middle-income countries, yet these are needed for monitoring the progress of national and global nutritional targets. We aimed to describe birthweight indicators at the national and subnational levels in Peru (2012-2019), and by selected correlates.

Methods

We studied mean birthweight (g), low birthweight (<2,500 g) and small for gestational age (according to international growth curves) prevalences. We analysed the national birth registry and summarized the three birthweight indicators at the national, regional, and province level, also by geographic area (Coast, Highlands, and Amazon). With individual-level data from the mother, we described the birthweight indicators by age, educational level and healthcare provider. Following an ecological approach (province level), we described the birthweight indicators by human development index (HDI), altitude above sea level, proportion of the population living in poverty and proportion of rural population.

Findings

Mean birthweight was always the lowest in the Highlands (2,954 g in 2019) yet the highest in the Coast (3,516 g in 2019). The same was observed for low birthweight and small for gestational age. In regions with Coast and Highlands, the birthweight indicators worsen from the Coast to the Highlands; the largest absolute difference in mean birthweight between Coast and Highlands in the same region was 367 g. All birthweight indicators were the worst in mothers with none/initial education, while they improved with higher HDI.

Interpretation

This analysis suggests that interventions are needed at the province level, given the large differences observed between Coast and Highlands even in the same region.

Funding

Wellcome Trust (214185/Z/18/Z).

Elevated risk of attention deficit hyperactivity disorder (ADHD) in Japanese children with higher genetic susceptibility to ADHD with a birth weight under 2000 g

BACKGROUND

Both genetic and pre- and perinatal factors, including birth weight, have been implicated in the onset of attention deficit hyperactivity disorder (ADHD) traits among children. This study aimed to elucidate to what extent the genetic risk of ADHD moderates the association between birth weight and ADHD traits among Japanese children.

METHODS

We conducted a longitudinal birth cohort study (Hamamatsu Birth Cohort for Mother and Children Study) to investigate the association of genetic risk for ADHD and low birth weight with ADHD traits among Japanese children. Out of 1258 children, we included 796 who completed follow-ups at 8 to 9 years of age. Birth weight was categorized as <2000 g, 2000-2499 g, and ≥2500 g. Polygenic risk score for ADHD was generated using the summary data of a large-scale genome-wide association study. The Rating Scale IV (ADHD-RS) assessed ADHD traits (inattention and hyperactivity/impulsivity) based on parental reports. Following previous studies, sex, birth order of the child, gestational age at birth, mother's age at delivery, educational attainment, pre-pregnancy body mass index, pre-pregnancy or during pregnancy smoking status, alcohol consumption during pregnancy, father's age, education, and annual family income were considered as covariates. Multivariable negative binomial regression was applied to evaluate the association between birth weight and ADHD traits, while adjusting for potential covariates. The interaction term between birth weight categories and binary polygenic risk was added to the model.

RESULTS

Birth weight of 2000-2499 g was not associated with ADHD traits. Birth weight under 2000 g was significantly associated with both inattention and hyperactivity. When accounting for higher and lower genetic risk for ADHD, only those with higher genetic risk and birth weight < 2000 g were associated with inattention (rate ratio [RR] 1.56, 95% CI 1.07-2.27) and hyperactivity (RR 1.87, 95% CI 1.14-3.06).

CONCLUSIONS

Birth weight under 2000 g, together with the genetic risk of ADHD, contributes to higher levels of ADHD traits among Japanese children aged 8 to 9 years. The suggested association between low birth weight and ADHD is confined to children with a genetic susceptibility to ADHD, indicating the relevance of genetic-environmental interactions in the etiology.

Factors determining cognitive, motor and language scores in low birth weight infants from North India

BACKGROUND

Children born with low birth weight (LBW) tend to have lower neurodevelopmental scores compared to term normal birth weight children. It is important to determine factors that influence neurodevelopment in these low birth weight children especially in the first 2-3 years of life that represents a period of substantial brain development.

METHODS

This secondary data analysis was conducted using data from LBW infants enrolled soon after birth in an individually randomized controlled trial (RCT) and followed up till end of 1st year. Neurodevelopmental assessment was done at 12 months of corrected age by trained psychologists using Bayley Scales of Infant and Toddler Development 3rd edition (Bayley-III). Factors influencing cognitive, motor and language scores were determined using multivariable linear regression model.

RESULTS

Linear growth (i.e., length for age z score, LAZ) [cognitive: Standardized ẞ-coefficient = 2.19, 95% CI; 1.29, 3.10; motor: 2.41, 95% CI; 1.59, 3.23; language: 1.37, 95% CI; 0.70, 2.04], stimulation at home [cognitive: 0.21, 95% CI; 0.15, 0.27; motor: 0.12, 95% CI; 0.07, 0.17; language: 0.21, 95% CI; 0.16, 0.25] and number of diarrhoeal episodes [cognitive: -2.87, 95% CI; -4.34, -1.39; motor: -2.62, 95% CI; -3.93, -1.29; language: -2.25, 95% CI; -3.32, -1.17] influenced the composite scores in all three domains i.e., cognitive, language and motor. While increase in LAZ score and stimulation led to increase in composite scores; an increase in number of diarrhoeal episodes was associated with decrease in scores. Weight for height z scores (WHZ) were associated with motor and language but not with cognitive scores. Additionally, a negative association of birth order with cognitive and language scores was noted.

CONCLUSIONS

The findings indicate the possible importance of promoting nutrition and preventing diarrhoea as well as ensuring optimal stimulation and nurturance at home for enhancing child development in LBW infants.

Poor Birth Outcomes in Malaria in Pregnancy: Recent Insights Into Mechanisms and Prevention Approaches

Pregnant women in malaria-endemic regions are susceptible to malaria in pregnancy, which has adverse consequences on birth outcomes, including having small for gestational age and preterm babies. These babies are likely to have low birthweights, which predisposes to infant mortality and lifelong morbidities. During malaria in pregnancy, Plasmodium falciparum-infected erythrocytes express a unique variant surface antigen, VAR2CSA, that mediates sequestration in the placenta. This process may initiate a range of host responses that contribute to placental inflammation and dysregulated placental development, which affects placental vasculogenesis, angiogenesis and nutrient transport. Collectively, these result in the impairment of placental functions, affecting fetal development. In this review, we provide an overview of malaria in pregnancy and the different pathological pathways leading to malaria in pregnancy-associated low birthweight. We also discuss current prevention and management strategies for malaria in pregnancy, and some potential therapeutic interventions that may improve birth outcomes. Lastly, we outline some priorities for future research that could bring us one step closer to reducing this health burden.

Diminished verbal ability among children conceived through ART with exposure to high serum estradiol in utero

Purpose

Higher serum estradiol levels occur in women undergoing assisted reproductive technology (ART) owing to ovarian stimulation. Here, we investigated the association between maternal serum estradiol levels and the intellectual development of offspring conceived with ART.

Methods

A total of 204 singletons born after fresh embryo transfer were recruited for this cohort study. Among them, 102 children were born from mothers with high serum estradiol levels (> 12,000 pmol/L) on the day that human chorionic gonadotropin was administered. Another 102 children, matched by gestational age and age of the children, were recruited as controls from mothers with low serum estradiol (≤ 12,000 pmol/L). The Wechsler Preschool and Primary Scale of Intelligence was used to evaluate the intellectual development of the children.

Results

Children from mothers with higher serum estradiol levels scored lower in the verbal intelligence quotient (IQ) tests and verbal comprehension than children whose mothers had lower estradiol levels. The main difference between the two groups was in verbal subtests including information, vocabulary, and sorting. Partial correlation analysis revealed that the logarithm of maternal serum estradiol level negatively correlated with verbal IQ, performance IQ, and full scale IQ.

Conclusion

Our data demonstrate that a high maternal serum estradiol level may negatively associate the verbal ability of children conceived via ART.

Long-term motor outcomes of very preterm and/or very low birth weight individuals without cerebral palsy: A review of the current evidence

We reviewed literature on long-term motor outcomes of individuals aged five years or older born very preterm (VP: ≤32 weeks of gestation) or with very low birth weight (VLBW: ≤1500g), without cerebral palsy (CP). PubMed produced 2827 articles, whereof 38 were eligible. Assessed by standardised and norm-based motor tests, the Movement Assessment Battery for Children being the most widely used, VP/VLBW individuals showed poorer motor skills compared with term-born controls with differences of approximately 1 SD in magnitude. Some studies assessed subdomains and differences were present in fine motor/manual dexterity, ball skills and gross motor/balance. Prevalence of motor problems varied largely from 8-37% in studies with cut-off at the 5th percentile or -1.5 SD to 12-71% in studies with cut-off at the 15th percentile or -1 SD. This review shows that the degree of motor impairments continues to be substantial among VP/VLBW individuals who do not develop CP.

Association between maternal HIV infection and birthweight in a tertiary hospital in southern Ethiopia: retrospective cohort study

BACKGROUND

Human Immunodeficiency Virus (HIV) infection and low birth weight (LBW) continue to be significant public health concerns in many low-income countries including Ethiopia. Yet the effect of maternal HIV infection on birth weight has not been thoroughly explored and the existing studies reported opposing findings. We examined the association between maternal HIV infection and LBW in a tertiary hospital in Southern Ethiopia.

METHODS

A retrospective cohort study was conducted based on the medical records of 277 HIV-negative and 252 HIV-positive mothers who gave singleton live birth between September 2014 to August 2017 in Hawassa University Comprehensive Specialized Hospital, Southern Ethiopia. The recodes were identified using systematic sampling approach and relevant information were extracted by using pretested extraction form. Multivariable binary logit model was fitted to examine the relationship between the exposure and outcome while adjusting for potential confounders. Adjusted odds ratio (AOR) and 95% confidence intervals (CI) is used for summarizing the findings of the analysis.

RESULTS

The mean (± standard deviation) birth weight of infants born to HIV-negative women (3.1 ± 0.7 kg) was significantly higher than those born to HIV-positive counterparts (3.0 ± 0.6 kg) (p = 0.020). The prevalence of LBW was also significantly higher in the HIV-exposed group (22.2%) than the non-exposed group (13.7%) (p = 0.011). In the logit model adjusted for multiple covariates, HIV-positive women had four times increased odds than HIV-negative women to give birth to LBW infant(AOR = 4.03, 95% CI: 2.01-8.06). Other significant predictors of LBW were rural place of residence (AOR = 2.04, 95% CI: 1.16-3.60), prenatal anemia (AOR = 3.17, 95% CI: 1.71-5.90), chronic hypertension (AOR = 3.68, 95% CI: 1.10-12.46) and preeclampsia (AOR = 6.80, 95% CI: 3.00-15.38).

CONCLUSION

Maternal HIV infection is associated with increased odds of LBW. HIV prevention activities are also likely to contribute for the reduction of LBW.

Community initiated kangaroo mother care and early child development in low birth weight infants in India-a randomized controlled trial

BACKGROUND

In a randomized controlled trial (RCT) with 8402 stable low birthweight (LBW) infants, majority being late preterm or term small for gestational age, community-initiated KMC (ciKMC) showed a significant improvement in survival. However, the effect of ciKMC on neurodevelopment is unclear. This is important to elucidate as children born with low birth weight are at high risk of neurodevelopmental deficits. In the first 552 stable LBW infants enrolled in the above trial, we evaluated the effect of ciKMC on neurodevelopmental outcomes during infancy.

METHOD

This RCT was conducted among 552 stable LBW infants, majorly late preterm or term small for gestational age infants without any problems at birth and weighing 1500-2250 g at birth. The intervention comprised of promotion of skin-to-skin contact and exclusive breastfeeding by trained intervention delivery team through home visits. The intervention group mother-infant-dyads were supported to practice ciKMC till day 28 after birth or until the baby wriggled-out. All infants in the intervention and control groups received Home Based Post Natal Care (HBPNC) visits by government health workers. Cognitive, language, motor and socio-emotional outcomes were assessed at infant-ages 6- and 12-months using Bayley Scale of Infant Development (BSID-III). Other outcomes measured were infant temperament, maternal depression, maternal sense of competence, mother-infant bonding and home-environment. We performed post-hoc equivalence testing using two one-sided tests of equivalence (TOST) to provide evidence that ciKMC does not do harm in terms of neurodevelopment.

RESULTS

In the intervention arm, the median (IQR) time to initiate ciKMC was 48 (48 to 72) hours after birth. The mean (SD) duration of skin-to-skin-contact was 27.9 (3.9) days with a mean (SD) of 8.7 (3.5) hours per day. We did not find significant effect of ciKMC on any of the child developmental outcomes during infancy. The TOST analysis demonstrated that composite scores for cognitive, language and motor domains at 12 months among the study arms were statistically equivalent.

CONCLUSION

Our study was unable to capture any effect of ciKMC on neurodevelopment during infancy in this sample of stable late preterm or term small for gestational age infants. Long term follow-up may provide meaningful insights.

TRIAL REGISTRATION

The trial is registered at clinicaltrials.gov NCT02631343 dated February 17, 2016; Retrospectively registered.

Impact of an integrated nutrition, health, water sanitation and hygiene, psychosocial care and support intervention package delivered during the pre- and peri-conception period and/or during pregnancy and early childhood on linear growth of infants in the first two years of life, birth outcomes and nutritional status of mothers: study protocol of a factorial, individually randomized controlled trial in India

Background

The period from conception to two years of life denotes a critical window of opportunity for promoting optimal growth and development of children. Poor nutrition and health in women of reproductive age and during pregnancy can negatively impact birth outcomes and subsequent infant survival, health and growth. Studies to improve birth outcomes and to achieve optimal growth and development in young children have usually tested the effect of standalone interventions in pregnancy and/or the postnatal period. It is not clearly known whether evidence-based interventions in the different domains such as health, nutrition, water sanitation and hygiene (WASH) and psychosocial care, when delivered together have a synergistic effect. Further, the effect of delivery of an intervention package in the pre and peri-conception period is not fully understood. This study was conceived with an aim to understand the impact of an integrated intervention package, delivered across the pre and peri-conception period, through pregnancy and till 24 months of child age on birth outcomes, growth and development in children.

Methods

An individually randomized controlled trial with factorial design is being conducted in urban and peri-urban low- to mid-socioeconomic neighbourhoods in South Delhi, India. 13,500 married women aged 18 to 30 years will be enrolled and randomized to receive either the pre and peri-conception intervention package or routine care (first randomization). Interventions will be delivered until women are confirmed to be pregnant or complete 18 months of follow up. Once pregnancy is confirmed, women are randomized again (second randomization) to receive either the intervention package for pregnancy and postnatal period or to routine care. Newborns will be followed up till 24 months of age. The interventions are delivered through different study teams. Outcome data are collected by an independent outcome ascertainment team.

Discussion

This study will demonstrate the improvement that can be achieved when key factors known to limit child growth and development are addressed together, throughout the continuum from pre and peri-conception until early childhood. The findings will increase our scientific understanding and provide guidance to nutrition programs in low- and middle-income settings.

Trial registration

Clinical Trial Registry – India #CTRI/2017/06/008908; Registered 23 June 2017, http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=19339&EncHid=&userName=society%20for%20applied%20studies

Size at birth and cognitive function among rural adolescents: a life course epidemiology study protocol of the Kisalaya cohort in Mysuru, South India

INTRODUCTION

It is proven that adverse intrauterine environment results in 'early life programming,' alterations in metabolism and physiological development of the fetus, often termed as 'Developmental Origins of Health and Disease' (DOHaD) resulting in a smaller size at birth, greater non-communicable diseases (NCD) risk factors during childhood and adolescence, and cardiometabolic disorders in adulthood. Nevertheless, very few studies have examined the relationship between DOHaD programming and cognition. This study aims to examine if impaired prenatal growth indicated by birth weight is associated with cognition among adolescents in the Kisalaya cohort, a rural birth cohort in South India, thus providing newer insights into DOHaD programming for adolescent mental health in a low-income and middle-income country setting.

METHODS AND ANALYSIS

Kisalaya cohort was established in 2008, to provide integrated antenatal care and HIV testing using mobile clinics to improve maternal and child health outcomes. This cohort included pregnant women residing in 144 villages of Mysuru Taluk (rural) who received antenatal care through mobile clinics and delivered their children between 2008 and 2011. Data related to mother-infant dyads for all pregnant women who received care in the Kisalaya programme are available for this study. Presently, children born to women who received care through Kisalaya are adolescents between 10 and 12 years. At this point, information would be collected on sociodemographic data and assessments of mental health, stressful life events, cognition, vision, speech, language, hearing and anthropometric measures would be done and relevant maternal data and child data, available from the cohort would be retracted for analysis. We plan to retrace as many adolescents as possible out of 1544 adolescents who are currently available for study excluding twins, abortions, stillbirths and postdelivery deaths. Analyses will be extended to construct a life course pathway for cognition using structural equation modelling.

Determinants of Cognitive Development in the Early Life of Children in Bhaktapur, Nepal

Background

Children in low and middle income countries may have many risk factors for poor cognitive development, and are accordingly at a high risk of not reaching their developmental potential. Determinants for cognitive development in early life can be found among biological and socioeconomic factors, as well as in stimulation and learning opportunities.

Objective

The present study aimed to identify determinants of cognitive, language and motor development in 6–11 months old Nepalese infants.

Methods

Six hundred infants with a length-for-age z-score <-1 were assessed with the Bayley Scales of Infant and Toddler development, 3rd edition (Bayley-III). Information on socioeconomic factors, child and maternal demographics, clinical and biological factors, and the home environment were collected. In a manual stepwise variable selection procedure, we examined the association between selected biological, socioeconomic and stimulation and learning opportunity variables and the Bayley-III cognitive, language and motor development subscale scores in multiple linear regression models.

Results

The length-for-age z-scores was positively associated with the cognitive composite score [standardized beta (ß): 0.22, p < 0.001] and the motor composite score [(ß): 0.14, p = 0.001]. Children born with low birth weight (<2500 g) scored significantly lower on all subscale scores. Diarrheal history was associated with poor language composite scores, and females had higher language composite scores than boys [(ß): 0.11, p = 0.015]. Children who had been hospitalized during the first month of life had also lower cognitive and motor composite scores than those who had not been hospitalized. Parental reports of physical punishment and lack of spontaneous vocalization were associated with poor cognitive and language composite scores, respectively. The statistical models with the various subscale scores as dependent variables explained between 8 to 16 percent of the variability in the cognitive developmental outcomes.

Conclusion

Our findings reveal important determinants for developmental scores in infancy, and underline the role of biological risk factors faced by marginalized children in low and middle income countries such as in Nepal.

Early life cognitive development trajectories and intelligence quotient in middle childhood and early adolescence in rural western China

The relationship of cognitive developmental trajectories during the dynamic first years with later life development outcomes remains unclear in low- and middle-income countries. 1388 Children born to women who participated in a randomized trial of antenatal micronutrient supplementation in rural China were prospectively followed. Cognitive development was assessed six times between 3 and 30 months of age using Bayley Scales of Infant Development, and then in mid-childhood (7-9 years) and early adolescence (10-12 years) using Wechsler Intelligence Scale for Children. We identified four distinct infant cognitive development trajectory subgroups using group-based trajectory modeling: (i) consistently above average, (ii) consistently average, (iii) started below average and then improved, and (iv) started below average and then declined. LBW infants (<2500 g) were 10.60 times (95% CI 3.57, 31.49) more likely to be in the trajectory group that started below average and then declined, while each grade increase in maternal education decreased the risk of being in this group by 73% (95% CI 54%, 84%). Infants who performed consistently above average had 8.02 (95% CI 1.46, 14.59) points higher IQ in adolescence versus the declining trajectory group. These findings suggest that interventions to improve early child development trajectories may produce long-term human capital benefits.