Perinatal and childhood risk factors of adverse early childhood developmental outcomes: systematic review

Abstract
Adverse early childhood developmental outcomes have pervasive effects on children's physical, social, emotional, cognitive, and language development. This comprehensive synthesis informs health promotion and disease prevention strategies by systematically identifying perinatal and childhood risk factors contributing to adverse developmental outcomes.
Methods
A systematic search of EMBASE, Medline, Global Health, PsycINFO, CINAHL, and Web of Science Core Collection from 2000 to 2023 was conducted. Studies meeting Population, Exposure, Comparison, Outcome, and Studies (PECOCS) criteria were included: 1) Population: Children under eight years undergoing developmental assessments; 2) Exposure: Various perinatal and childhood risk factors; 3) Comparison: Children with minimal exposure to risk factors, 4) Outcome: Adverse early childhood developmental outcomes, 5) Study design: Observational studies including cohort, case-control, nested case-control, and cross-sectional studies.
Results
Out of 27,376 identified studies, 175 were analysed, representing over 80 countries, with a concentration in Australia, the US, Canada, and China. More than 43 assessment tools were utilised. Perinatal risk factors such as gestational age, birth weight, maternal age, maternal mental health issues, tobacco smoking, and maternal anaemia emerged as significant contributors to adverse developmental outcomes. Childhood-related factors, including chronic illness, hospitalisation, surgery exposure, infectious diseases, excessive screen time, physical inactivity, and inadequate sleep, were identified as risk factors across multiple developmental domains. Environmental influences such as indoor air pollution, proximity to major roads, and exposure to various chemicals also had significant impacts.
Interpretation
Multifaceted risk factors influence early childhood development. Understanding these interconnected factors is crucial for designing interventions to promote optimal development and mitigate adversities. Holistic approaches addressing these influences can ensure every child can thrive and reach their full potential.

Context and Aim
In Australia, large health disparities are observed between population groups defined by geography, sex, ethnicity and socio-economic position. However, national and state averages may mask disparities between discrete communities in which people live, offering little to guide local public health action. As part of an investigation into health inequalities within the catchment of the recently established Western Public Health Unit (WPHU), we explored the prevalence of self-reported diabetes in 25–49-year-olds, using small-area data from the 2021 Census and applying an intersectionality lens.

Methods and findings
We calculated the prevalence of self-reported diabetes in the WPHU catchment and stratified by local government area (LGA), area-level index of relative socio-economic disadvantage (IRSD quintile at Statistical Area 1 level) and sex. The prevalence of diabetes was 30% higher among populations living in quintile 1 areas (the most socio-economically disadvantaged) compared to quintile 5 areas (3.2% vs 2.0%) The double-disaggregation of sex and IRSD revealed evidence of gender inequity, whereby the effect of socioeconomic disadvantage on diabetes prevalence was greater for women than men. This was more evident in outer-suburban local government areas. In one LGA with high overall prevalence of diabetes for both sexes (2.9%), the prevalence in women was 230% higher in the most disadvantaged areas compared to the least disadvantaged. In contrast, the difference in prevalence for men between the most and least disadvantaged areas was 40%.

Translational outcomes
Our results suggest that underlying gender inequity (social structures, attitudes and allocation of resources and power that bias against women) may be more pronounced in some areas and hence, socioeconomic status has a greater impact on health for women than men in these areas. WPHU will consider where sex and socioeconomics may interplay in programs, initiatives or policy, to ensure we provide equitable public health.

Future actions
WPHU will continue to explore gender dynamics that may be playing out across the catchment and underpinning these findings. We will consider additional indicators that include processes, risk factors and behaviours which could highlight key drivers of the inequalities revealed in this analysis and inform future interventions.

In regions of India where caste systems deeply influence social dynamics, women experiencing intimate partner violence (IPV) poses risk to the lives of newborns, infants, and children. This study investigates the impact of IPV on child mortality across various caste groups, exploring how IPV within families affects the survival of the most vulnerable. Addressing IPV within these social structures is crucial, not only for the immediate safety of individuals but also for the broader goal of improving child health outcomes and maternal well-being. By examining the impact of IPV in caste dynamics on child mortality, this research aims to uncover underlying factors that perpetuate these issues.
This study used data from recent National Family Health Surveys (NFHS) in India from 2015 to 2021, involving 58,685 mother-child pairs who completed the prevalence of IPV. Adjusted odds ratios (aOR) were used to assess the impact of caste-based intimate partner violence (IPV) on child mortality.
Mothers from upper castes experiencing intimate partner violence (IPV) have a significant impact with an increased likelihood of neonatal (1.715***), infant (1.488***), and child mortality (1.434***) compared to mothers from lower castes who face IPV. This difference could be due to varied access to resources, coping strategies, and community support. Despite having better healthcare and education, mothers from upper castes may endure more psychological stress and societal pressure from IPV, which can adversely affect their children. Conversely, mothers from lower castes often benefit from stronger community ties and more effective coping methods, protecting their children from IPV's impacts. Additionally, these mothers typically work, potentially enhancing their empowerment and household bargaining power, aiding them in managing IPV more effectively. This scenario demonstrates how socio-economic and cultural factors significantly shape the effects of IPV in caste dynamics on child mortality, emphasising the importance of tailored interventions.
Tackling IPV in caste-specific situations is essential to protect the health of mothers and children. Further, incorporating IPV interventions into existing programs can significantly improve survival rates for newborns and children in India, while also ensuring maternal health.

What is the issue that requires public health action?

People who are homeless experience enormous health disparities, including a three-decade life expectancy gap and a high prevalence of chronic disease. Conventional public health campaigns rarely reach this population, who encounter barriers to healthcare access and healthy behaviours and who are rarely recognised as a priority group due to largely being invisible in general population health data.

What have we learned to address this issue, and how has this finding been derived?

Using rich longitudinal health data for 1,482 patients of a specialist homelessness primary care practice, we examined the prevalence and risk factors for preventable chronic conditions and barriers and enablers to health promotion salience and preventive health. Factors examined included tobacco use, blood pressure, diabetes assessment and cancer screening.

The prevalence of chronic disease risk factors and conditions is high, and many barriers to preventive healthcare access exist. Daily survival can take precedence, but many patients were interested and engaged in improving their health. Primary health care providers with established trust can be a valuable conduit for health promotion.

How has this been used in practice?

This research involved collaboration with a large provider of primary care services to people experiencing homelessness, with a shared commitment to increasing preventive health access and support for this population. Implications for public health programs are being shared and an advocacy strategy has been developed promoting recognition of people experiencing homelessness as a priority group in key national and state health strategies.

What actions should we take in the future?

Trauma, adversity and social exclusion contribute to the high prevalence of preventable disease in homeless populations and other vulnerable groups. Mainstream public health interventions should recognise this and be trauma-informed, and tailored strategies should be developed to reduce the preventable life expectancy gap.