Abstract
Background: Under-five mortality (U5M) remains a critical public health challenge in low- and lower-middle-income countries (LLMICs), where over 90% of global deaths occur. Despite progress, the changing contribution of risk factors to U5M remains unexplored in LLMICs.
Methods: We analysed Demographic and Health Survey (DHS) data from 24 LLMICs across two periods: 1997-2005 and 2016-2022. We included 139,890 live births in 1997-2005 and 319,034 in 2016-2022. We employed a mixed-effects robust Poisson regression model with a log link function to identify risk factors of U5M for each period. Population-attributable fractions (PAFs) were calculated and compared to investigate changes in the contributions of risk factors over time.
Results: Under-five mortality attributable to never having been breastfed increased by 15.5 percentage points (95% CI: 8.6, 22.9), by 5.4 percentage points (95% CI: 3.1, 5.7) for early maternal age at birth (<20 years), and by 1.2 percentage points (95% CI: 0.4, 1.8) for plural births. U5M reductions attributable to maternal secondary education were increased by 5.5 percentage points (95% CI: 0.4, 11.0), and reductions due to tertiary education increased by 2.6 percentage points (95% CI: 1.6, 4.2). However, U5M reductions associated with 1-3 antenatal care (ANC) visits were decreased by 7.2 percentage points (95% CI: 2.4, 11.7).
Conclusions: The contributions of risk factors to U5M have changed over time. Interventions need to prioritise promoting breastfeeding, enhancing maternal education and increasing ANC uptake, and addressing other significant contributors to U5M.

Abstract
Background: Rural sub-Saharan Africa faces systemic challenges like food insecurity, malnutrition, and limited healthcare, impacting health outcomes. This study examines maternal iron supplementation adherence and socio-economic factors influencing its association with low birth weight (LBW) among rural women.
Methods: Demographic and Health Survey (DHS) data from 196,076 rural women across 26 sub-Saharan countries were analysed. A generalised linear mixed-effects model assessed adherence to iron supplementation (≥90 days) and its association with LBW, stratified by socio-economic factors and service access. Results were reported as odds ratios (ORs) with 95% confidence intervals (CIs), with p ≤ 0.05 indicating significance.
Results: Adherence to iron supplementation in rural sub-Saharan Africa was 31.58%, lower among uneducated women (25.62%) and those from the poorest families (28.05%). Overall, not taking iron during pregnancy among rural women increased LBW odds (aOR=1.13; 95%CI: 1.04, 1.23). In contrast, taking iron for ≥90 days reduced LBW odds (aOR=0.82; 95%CI: 0.74, 0.90). Further, adherence to supplementation reduced the odds of LBW among uneducated women (aOR=0.78; 95%CI: 0.66, 0.90), women with low family income (aOR=0.71; 95%CI: 0.63, 0.81), did not work (aOR=0.74; 95%CI: 0.63, 0.87), and partner with lower education (aOR=0.85; 95%CI: 0.75, 0.95).
Conclusions: Adherence to iron supplementation (≥90 days) during pregnancy in rural sub-Saharan Africa was low; however, adherence reduced the odds of LBW, particularly among uneducated, lower partner education, and low-income women. Developing health-promoting strategies to facilitate uptake and optimum adherence of iron supplementation into community health programs and providing vocational training for rural women is necessary.
Keywords: Iron supplementation, Rural Area, Low Birth Weight, Sub-Saharan Africa

Abstract
Background: Women’s empowerment directly influences the quality and timeliness of the maternal healthcare they receive. A lack of women's empowerment, particularly in low- and middle-income countries (LMICs), is likely to contribute to poor uptake of maternal health care. This study aims to evaluate the role of women's empowerment in maternal healthcare in LMICs.
Methods: We used the recent Demographic and Health Survey (DHS) data from 35 LMICs. A total of 71,077 married/partnered women were included. Women were categorised as empowered if they participated in all decision-making activities and were able to disagree that a husband is justified in hitting or beating his wife for any reason. A logit propensity score matching (PSM) analysis was used to estimate the effect of women's empowerment on maternal health services.
Result: In this study, only one-third (33.8%) of reproductive-age women in LMICs (95% CI: 27.7%, 40.8%) reported being empowered. Women’s empowerment was associated with an 11.2 percentage point increase in having adequate ANC visits (average treatment effects on the treated (ATT) of 0.112, standard error (SE): 0.026), and an 8.0 percentage point increase in the likelihood of health facility childbirth (ATT=0.078, SE: 0.039). However, there was insufficient evidence for early PNC visits.
Conclusion: Empowering women has a positive association with the utilisation of adequate ANC visits and health facility childbirth in LMICs. These findings underscore the necessity for public health programs aimed at empowering women and enhancing their decision-making abilities to improve maternal health care uptake, such as health facility childbirth and ANC visits.

Background: Chronic exposure to air pollution during early life is associated with increased risks of high blood pressure in childhood. However, there is limited research on the long-term effects of acute, high-intensity air pollution events, such as wildfire smoke. This study aimed to investigate the association between exposure during pregnancy and infancy to PM2.5 from the 2014 Hazelwood coal mine fire in the Latrobe Valley, Victoria, and blood pressure in later childhood.
Methods: A cohort of 293 children classified into three groups: exposure while in-utero (n=100), exposure during infancy (from birth to 2 years of age, n=122) and not exposed (n=71), undertook brachial and central (aortic) blood pressure assessments at 3, 7 and 9 years after the fire. Individual mean and peak daily exposures to mine fire PM2.5 were calculated by mapping time-location diaries against modelled temporospatial pollution estimates. Multivariable linear regression models adjusted for potential confounders, were used to evaluate the association between PM2.5 exposure and blood pressure. Rate of change in blood pressure measurements from 3 to 9 years after the fire was conducted by comparing exposed with unexposed groups of children.
Results: At the 9-year follow-up, each 10 µg/m3 increase in mean fire-related PM2.5 was associated with a 2.48 mmHg increase in central DBP (95% CI: 0.73, 4.88) among children exposed during infancy. Being exposed to fire smoke during infancy was also associated with an annual increase from 3 to 9 years after the fire in brachial SBP (2.18 mmHg [95% CI: 1.11, 3.24]), brachial DBP (1.90 mmHg, [95% CI: 0.95, 2.86]), central SBP (1.58 mmHg [95% CI: 0.59, 2.56]) and central DBP (1.86 mmHg [95% CI: 0.85, 2.88]) than for the unexposed group.
Conclusions: Exposure to high levels of air pollution during infancy was associated with long-term increased blood pressure in later childhood.

Background

Atopic dermatitis (AD) and food allergy (FA) are common disorder in children, and an impaired skin barrier has been implicated in the pathogenesis of these diseases. Lipids are one of the key components of skin that maintain barrier function. Skin lipids are complex structures and encompass different species that are interdependent. We have previously shown that low levels of protein-bound ω-hydroxy fatty acids sphingosine ceramides (POS-CER, type of skin lipids) are associated with increased risk of “AD without allergic sensitisation”. However, whether particular lipids are important in the aetiology of AD with or without FA remains unknown.

Methods

Skin lipids were sampled at 6-weeks of age from 133 children with a family history of allergic diseases, and 176 lipid species were identified and measured using liquid chromatography-tandem mass spectrometry. AD was assessed at 1-year of age using modified UK Working Party Criteria. FA was assessed based on food allergic sensitisation, oral food challenges and parent-reported food reaction history. Lipid profiles were characterised using Uniform Manifold Approximation and Projection (UMAP). Associations between skin lipid profiles and the development of AD/FA phenotypes were estimated using multinominal logistic regression.

Results

We identified 5 lipid profiles. In unadjusted models, 19% of children had a profile with lower levels of POS-CER profile at 6-weeks of age were at increased risk of “AD without FA” (OR=3.35, 95%CI:1.24-9.06, p=0.02) but not “AD with FA” at 1-year of age, compared to children without this profile. These associations became insignificant when adjusted for possible confounders (OR=2.70, 95%CI:0.94-7.76, p=0.07).

Conclusions

A predominated low POS-CER profile was associated with the development of “AD without concurrent FA” but not “AD with FA”. Findings are similar with a previous independent study, supporting that reduced levels of POS-CER may have a role in the pathogenesis of AD without FA at 1-year of age.

Objective: To determine the association between perinatal artificially sweetened beverage (ASB) consumption and adverse pregnancy outcomes such as gestational diabetes mellitus (GDM), hypertensive disorder of pregnancy (HDP), and preterm birth (PTB).
Methods: We analysed data from the Australian Longitudinal Study on Women’s Health (ALSWH). For GDM and HDP, we analysed 3,653 women (2,168 and 1,485 women for preconception and pregnancy exposure assessment, respectively: mutually exclusive participants). For PTB, we analysed 2,796 women (1,673 and 1,123 women for preconception and pregnancy exposure assessment, respectively: mutually exclusive participants). A generalized linear mixed model and augmented inverse probability weighting estimator were used to estimate the relative risk and average treatment effect (ATE), respectively. All models were adjusted for confounders identified a priori.
Results: The incidence of GDM, HDP, and PTB in the preconception exposure group was 9.1%, 6.7%, and 4.3%, while in the pregnancy exposure group it was 8.6%, 7.5%, and 4.0%, respectively. The adjusted relative risk (aRR) of frequent preconception ASB (≥5 drinks/week) compared to no or rare intake was 1.41 (95% confidence interval [CI] 0.91–2.16) for GDM, 1.17 (95% CI 0.68–2.01) for HDP, and 0.93 (95% CI 0.41–2.07) for PTB. Frequent consumption of ASB (≥5 drinks/week) during pregnancy was associated with an increased risk of GDM (aRR 1.88; 95% CI 1.12–3.14), HDP (aRR 1.59; 95% CI 0.86–2.93), and PTB (aRR 1.22; 95% CI 0.36–3.99) compared with no or rare consumption. The effect estimates for HDP and PTB were imprecise. The ATE of frequent ASB intake during pregnancy showed an increased risk of GDM (ATE = 0.06; 95% CI 0.01–0.11).
Conclusions: Frequent ASB consumption during pregnancy is associated with increased risk of GDM. The association between ASB intake during pregnancy with HDP and PTB, as well as preconception ASB intake and all outcomes, remain inconclusive.

Background:
Asthma is one of the most common chronic diseases among children in Australia, placing significant burden on individuals and society in terms of quality of life and long-term morbidity. Current monitoring relies on stand-alone survey and administrative data, limiting the ability to report on the needs and health care experiences of children with asthma.
The aim of this work was to estimate the prevalence and characteristics of asthma-related service users among children aged 1–14 in linked administrative health data.

Methods:
Analysis was conducted using de-identified linked Medicare Benefits Schedule (MBS) and Pharmaceutical Benefits Scheme (PBS) data from the National Health Data Hub (NHDH). Children were included if they were living, eligible for Medicare and aged 1–14 years in the study period. Asthma-related health service use was defined as having been dispensed at least 2 asthma-related PBS medications and/or claimed an asthma cycle-of-care MBS item in the year. Annual prevalence was calculated as proportion of children with asthma-related health claims among eligible children in the year. PBS claims were also used classify children as likely having either mild, moderate or severe asthma.

Results:
In 2020–21, 4.8% of children aged 1–14 (n=219,000) were identified as asthma-related health service users. Prevalence of asthma-related service use was:
• higher among boys than girls
• higher among those living in the most disadvantaged areas compared with the highest
• highest in Inner regional areas.
Of these children:
• 21% started using asthma-related health services in 2020–21.
• 49% were considered to have mild asthma, 34% moderate asthma and 17% severe asthma, based on medication dispensed.

Conclusion:
National linked administrative health data, such as the NHDH, is a valuable resource for asthma-related service use among children. It also presents opportunities exploring health care journeys, disease across the life course, and improved population health monitoring.

Abstract
Background: Childhood height is influenced by both genetic (heritability) and environmental factors. However, it is unclear how these factors vary by geographical region and by study design, particularly in developing countries where data is scarce. Understanding these variations will aid the identification of factors that may be hindering growth in specific populations.
Methods: We analysed height data from 17,066 twin and 2,024,672 parent-offspring pairs across 69 countries, using the Demographic and Health Survey (DHS) database. We classified countries into four regions: Sub-Saharan Africa (SSA), North Africa/West Asia/Europe (NAWAE), Central, South & Southeast Asia (Asia) and Latin America & Caribbean (LAC). We estimated genetic and environmental contributions to childhood height using a mixture distribution method for twins with unknown zygosity and a parent-offspring regression for singletons.
Results: The mean height of children aged 0-5 years varied geographically, with the tallest children in NAWAE (twins: 84.18 ± 14.88 cm; singletons: 85.05 ±14.86 cm) and the shortest in SSA (twins: 78.85 ± 14.61cm; singletons: 81.28 ± 14.07 cm). Twin studies consistently estimated heritability at around 0.35 (95%CI, 0.34-0.37) across all regions. Conversely, there was variation in the estimates from family studies, ranging from 0.27 (95%CI,0.26-0.30) in NAWAE to 0.47 (95%CI,0.46-0.48) in LAC.
Conclusion: Our findings confirm that genetic factors significantly influence childhood height across diverse populations. However, the observed discrepancies between twin and family study estimates underscore the complex interplay between genetic and environmental factors. These variations suggest that environmental factors play a critical role in determining height outcomes during childhood. Further research is needed to explore these environmental factors in greater detail with the aim of developing region-specific interventions to address height disparities, particularly in underprivileged regions.