Zero-dose children and the extended immunisation cascade: Understanding the path to full immunisation with six childhood vaccines in 43 countries.

Background: As part of the Immunisation Agenda 2030, the World Health Organization set a goal to reduce the number of children who did not receive any routine vaccine by 50% by 2030. We aimed to describe the patterns of vaccines received for children with zero, one, and up to full vaccination, while considering newly deployed vaccines (pneumococcal conjugate vaccine (PCV) and rotavirus (ROTA) vaccine) alongside longstanding ones such as the Bacille Calmete-Guérin (BCG), diphtheria, tetanus, and pertussis (DPT), and poliomyelitis vaccines, and measles-containing vaccines (MCVs). Methods: We used data from national household surveys (Demographic and Health Surveys and Multiple Indicator Cluster Surveys) carried out in 43 low- and middle-income countries since 2014. We calculated the immunisation cascade as a score ranging from zero to six, considering BCG, polio, DPT, and ROTA vaccines, and the MCV and PCV. We also described the most prevalent combination of vaccines. The analyses were pooled across countries and stratified by household wealth quintiles. Results: In the pooled analyses with all countries combined, 9.0% of children failed to receive any vaccines, 58.6% received at least one dose of each of the six vaccines, and 47.2% were fully vaccinated with all doses. Among the few children receiving 1-5 vaccines, the most frequent were BCG vaccines, polio vaccines, DPT vaccines, PCV, ROTA vaccines, and MCV. Conclusions: Targeting children with their initial vaccine is crucial, as those who receive a first vaccine are more likely to undergo subsequent vaccinations. Finding zero-dose children and starting their immunisation is essential to leaving no one behind during the era of Sustainable Development Goals.

Global inequities in adverse pregnancy outcomes: what can we do?

The Health Equity Leadership & Exchange Network states that "health equity exists when all people, regardless of race, sex, sexual orientation, disability, socioeconomic status, geographic location, or other societal constructs, have fair and just access, opportunity, and resources to achieve their highest potential for health." It is clear from the wide discrepancies in maternal and infant mortalities, by race, ethnicity, location, and social and economic status, that health equity has not been achieved in pregnancy care. Although the most obvious evidence of inequities is in low-resource settings, inequities also exist in high-resource settings. In this presentation, based on the Global Pregnancy Collaboration Workshop, which addressed this issue, the bases for the differences in outcomes were explored. Several different settings in which inequities exist in high- and low-resource settings were reviewed. Apparent causes include social drivers of health, such as low income, inadequate housing, suboptimal access to clean water, structural racism, and growing maternal healthcare deserts globally. In addition, a question is asked whether maternal health inequities will extend to and be partially due to current research practices. Our overview of inequities provides approaches to resolve these inequities, which are relevant to low- and high-resource settings. Based on the evidence, recommendations have been provided to increase health equity in pregnancy care. Unfortunately, some of these inequities are more amenable to resolution than others. Therefore, continued attention to these inequities and innovative thinking and research to seek solutions to these inequities are encouraged.

Mental health from childhood to adolescence predicts excessive weight and body composition at 18 years.

OBJECTIVE: To investigate the association of mental health in childhood and adolescence with four outcomes at 18 years: ultra-processed food (UPF) consumption, body mass index (BMI), excessive weight (EW), and body composition, including fat mass (FM) and fat free mass (FFM) in kg, FM index (FMI) and FFM index (FFMI) in kg/m2. METHODS: Cohort study in which The Development and Well-Being Assessment (DAWBA) (6 and 11 years) and the MINI International Neuropsychiatric Interview (MINI) (18 years) provided information on internalizing (INT), externalizing (EXT) and any mental disorder (ANY). The exposure was classified in: "never", "at 6 and/or 11 years", "at 18 years only" and "at 6, 11, and 18 years". Linear and logistic regression were run. All analyses were stratified by sex. RESULTS: A total of 2722 participants were analyzed. At 18 years, female with EXT disorders at 6 and/or 11 years presented higher BMI (ß: 1.70; 0.18-3.23), FM (ß: 4.74; 1.42-8.06), and FMI (ß: 1.53; 0.28-2.79) than those who never had. The odds of EW at 18 years was also higher in females with EXT disorders at 6 and/or 11 years (OR: 3.39; 1.56-7.36) and at the three time points (OR: 7.08; 1.69-29.59). Males with EXT disorders at 6 and/or 11 years presented higher FM (ß: 4.45; 1.85-7.06) and FMI (ß: 1.47; 0.63-2.31). CONCLUSIONS: Among children and adolescents showing symptoms of EXT disorders, weight should be monitored carefully, thus ultimately contributing to reduce the burden of EW in adolescence.

Predictors of early child development for screening pregnant women most in need of support in Brazil.

Background: Home visiting programmes can support child development and reduce inequalities, but failure to identify the most vulnerable families can undermine such efforts. We examined whether there are strong predictors of poor child development that could be used to screen pregnant women in primary health care settings to target early interventions in a Brazilian population. Considering selected predictors, we assessed coverage and focus of a large-scale home visiting programme named Primeira Infância Melhor (PIM). Methods: We undertook a prospective cohort study on 3603 children whom we followed from gestation to age four years. We then used 27 potential socioeconomic, psychosocial, and clinical risk factors measurable during pregnancy to predict child development, which was assessed by the Battelle Developmental Inventory (BDI) at the age of four years. We compared the results from a Bonferroni-adjusted conditional inference tree with exploratory linear regression and principal component analysis (PCA), and we conducted external validation using data from a second cohort from the same population. Lastly, we assessed PIM coverage and focus by linking 2015 cohort data with PIM databases. Results: The decision tree analyses identified maternal schooling as the most important variable for predicting BDI, followed by paternal schooling. Based on these variables, a group of 214 children who had the lowest mean BDI (BDI = -0.48; 95% confidence interval (CI) = -0.63, -0.33) was defined by mothers with ≤5 years and fathers with ≤4 years of schooling. Maternal and paternal schooling were also the strongest predictors in the exploratory analysis using regression and PCA, showing linear associations with the outcome. However, their capacity to explain outcome variance was low, with an adjusted R2 of 5.3% and an area under the receiver operating characteristic curve of 0.62 (95% CI = 0.60, 0.64). External validation showed consistent results. We also provided an online screening tool using parental schooling data to support programme's targeting. PIM coverage during pregnancy was low, but the focus was adequate, especially among families with longer enrolment, indicating families most in need received higher dosage. Conclusions: Information on maternal and paternal schooling can improve the focus of home visiting programmes if used for initial population-level screening of pregnant women in Brazil. However, enrolment decisions require complementary information on parental resources and direct interactions with families to jointly decide on inclusion.

Changes of adolescent sleep patterns during the COVID-19 pandemic.

OBJECTIVE: The COVID-19 pandemic has raised numerous concerns regarding its effects on individuals' health and lifestyle. We aim to analyze potential changes in adolescent sleep patterns from before and during the pandemic and identify specific predictors of changes. METHODS: A subgroup of adolescents from a population-based birth cohort from Pelotas, Brazil, was assessed pre-pandemic (T1, November-2019 to March-2020) and peri-pandemic (T2, August-2021 to December-2021) in in-person interviews (n = 1,949). Sleep parameters, including sleep duration and latency time on workdays and free days, as well as social jetlag (SJL), were assessed using the Munich ChronoType Questionnaire (MCTQ). Socio-demographic, pre-pandemic, and pandemic-related predictors were analyzed. Changes in sleep parameters from T1 to T2 were estimated by multivariate latent change score modeling. RESULTS: The latent change factor shows a significant mean increase in workday sleep duration (M = 0.334, p < 0.001), workday sleep latency (M = 0.029, p = 0.002), and free day sleep latency (M = 0.021, p = 0.034), and a decreased in SJL (M = -0.758, p < 0.001) during the pandemic. Female adolescents presented higher increases in workday sleep duration. Adolescents who adopted a stricter social distancing level during the pandemic presented greater increases in workday sleep duration and smaller reductions in SJL. Self-evaluated insomnia during the pandemic predicted lower increases in workday and free day sleep duration and higher increases in workday and free day sleep latency. CONCLUSION: The COVID-19 outbreak brought certain advantages regarding increased sleep duration and reduced SJL. However, the observed increase in sleep latency and the influence of self-reported insomnia could be related to psychological distress inherent to the pandemic.

Exploring the "Urban Advantage" in Access to Immunization Services: A Comparison of Zero-Dose Prevalence Between Rural, and Poor and Non-poor Urban Households Across 97 Low- and Middle-Income Countries.

Urban children are more likely to be vaccinated than rural children, but that advantage is not evenly distributed. Children living in poor urban areas face unique challenges, living far from health facilities and with lower-quality health services, which can impact their access to life-saving vaccines. Our goal was to compare the prevalence of zero-dose children in poor and non-poor urban and rural areas of low- and middle-income countries (LMICs). Zero-dose children were those who failed to receive any dose of a diphtheria-pertussis-tetanus (DPT) containing vaccine. We used data from nationally representative household surveys of 97 LMICs to investigate 201,283 children aged 12-23 months. The pooled prevalence of zero-dose children was 6.5% among the urban non-poor, 12.6% for the urban poor, and 14.7% for the rural areas. There were significant differences between these areas in 43 countries. In most of these countries, the non-poor urban children were at an advantage compared to the urban poor, who were still better off or similar to rural children. Our results emphasize the inequalities between urban and rural areas, but also within urban areas, highlighting the challenges faced by poor urban and rural children. Outreach programs and community interventions that can reach poor urban and rural communities-along with strengthening of current vaccination programs and services-are important steps to reduce inequalities and ensure that no child is left unvaccinated.

Association between women's empowerment and demand for family planning satisfied among Christians and Muslims in multireligious African countries.

BACKGROUND: Although the levels of demand for family planning satisfied (DFPS) have increased in many countries, cultural norms remain a significant barrier in low- and middle-income countries. In the context of multireligious African countries, our objective was to investigate intersectional inequalities in DFPS by modern or traditional contraceptives according to religion and women's empowerment. METHODS: Analyses were based on Demographic and Health Surveys carried out between 2010 and 2021 in African countries. Countries with at least 10% of Muslims and Christians were selected to analyse inequalities in family planning. The religious groups were characterised by wealth, area of residence, women's age and women's empowerment. The mean level of empowerment was estimated for each religious group, and multilevel Poisson regression was used to assess whether DFPS varied based on the level of women's empowerment among Muslims and Christians. RESULTS: Our study sample of 14 countries comprised 35% of Muslim and 61% of Christian women. Christians had higher levels of empowerment across all three domains compared with Muslims and women with no/other religion. DFPS was also higher among Christians (57%) than among Muslims (36%). Pooled analysis indicated a consistent association between DFPS and women's empowerment, with higher prevalence ratios among Muslims than Christians, especially in the decision-making domain. CONCLUSIONS: The gap between Muslims and Christians in DFPS significantly reduced as the level of empowerment increased. It highlights the importance of understanding and addressing cultural factors sensibly and respectfully to satisfy the demand for family planning services.

Policies for expanding family planning coverage: lessons from five successful countries.

Background: Enhancing the design of family planning interventions is crucial for promoting gender equality and improving maternal and child health outcomes. We identified, critically appraised, and synthesized policies and strategies from five selected countries that successfully increased family planning coverage. Methods: We conducted a policy analysis through a scoping review and document search, focusing on documents published from 1950 to 2023 that examined or assessed policies aimed at enhancing family planning coverage in Brazil, Ecuador, Egypt, Ethiopia, and Rwanda. A search was conducted through PubMed, SCOPUS, and Web of Science. Government documents and conference proceedings were also critically analyzed. National health surveys were analyzed to estimate time trends in demand for family planning satisfied by modern methods (mDFPS) at the national level and by wealth. Changes in the method mix were also assessed. The findings of the studies were presented in a narrative synthesis. Findings: We selected 231 studies, in which 196 policies were identified. All countries started to endorse family planning in the 1960s, with the number of identified policies ranging between 21 in Ecuador and 52 in Ethiopia. Most of the policies exclusively targeted women and were related to supplying contraceptives and enhancing the quality of the services. Little focus was found on monitoring and evaluation of the policies implemented. Conclusion: Among the five selected countries, a multitude of actions were happening simultaneously, each with its own vigor and enthusiasm. Our findings highlight that these five countries were successful in increasing family planning coverage by implementing broader multi-sectoral policies and considering the diverse needs of the population, as well as the specific contextual factors at play. Successful policies require a nuanced consideration of how these policies align with each culture's framework, recognizing that both sociocultural norms and the impact of past public policies shape the current state of family planning.

Gene - maltreatment interplay in adult ADHD symptoms: main role of a gene-environment correlation effect in a Brazilian population longitudinal study.

Childhood maltreatment correlates with attention-deficit/hyperactivity disorder (ADHD) in previous research. The interaction between ADHD genetic predisposition and maltreatment's impact on ADHD symptom risk remains unclear. We aimed to elucidate this relationship by examining the interplay between a polygenic score for ADHD (ADHD-PGS) and childhood maltreatment in predicting ADHD symptoms during young adulthood. Using data from the 2004 Pelotas (Brazil) birth cohort comprising 4231 participants, we analyzed gene-environment interaction (GxE) and correlation (rGE). We further explored rGE mechanisms through mediation models. ADHD symptoms were assessed at age 18 via self-report (Adult Self Report Scale - ASRS) and mother-reports (Strength and Difficulties Questionnaire - SDQ). The ADHD-PGS was derived from published ADHD GWAS meta-analysis. Physical and psychological child maltreatment was gauged using the Parent-Child Conflict Tactics Scale (CTSPC) at ages 6 and 11, with a mean score utilized as a variable. The ADHD-PGS exhibited associations with ADHD symptoms on both ASRS (ß = 0.53; 95% CI: 0.03; 1.03, p = 0.036), and SDQ (ß = 0.20; 95% CI: 0.08; 0.32, p = 0.001) scales. The total mean maltreatment score was associated with ADHD symptoms using both scales [(ßASRS = 0.51; 95% CI: 0.26;0.77) and (ßSDQ = 0.24; 95% CI: 0.18;0.29)]. The ADHD-PGS was associated with total mean maltreatment scores (ß = 0.09; 95% CI: 0.01; 0.17; p = 0.030). Approximately 47% of the total effect of ADHD-PGS on maltreatment was mediated by ADHD symptoms at age 6. No evidence supported gene-environment interaction in predicting ADHD symptoms. Our findings underscore the significant roles of genetics and childhood maltreatment as predictors for ADHD symptoms in adulthood, while also indicating a potential evocative mechanism through gene-environment correlation.

Comparison of Wealth-Related Inequality in Tetanus Vaccination Coverage before and during Pregnancy: A Cross-Sectional Analysis of 72 Low- and Middle-Income Countries.

Immunization of pregnant women against tetanus is a key strategy for reducing tetanus morbidity and mortality while also achieving the goal of maternal and neonatal tetanus elimination. Despite substantial progress in improving newborn protection from tetanus at birth through maternal immunization, umbilical cord practices and sterilized and safe deliveries, inequitable gaps in protection remain. Notably, an infant's tetanus protection at birth is comprised of immunization received by the mother during and before the pregnancy (e.g., through childhood vaccination, booster doses, mass vaccination campaigns, or during prior pregnancies). In this work, we examine wealth-related inequalities in maternal tetanus toxoid containing vaccination coverage before pregnancy, during pregnancy, and at birth for 72 low- and middle-income countries with a recent Demographic and Health Survey or Multiple Indicator Cluster Survey (between 2013 and 2022). We summarize coverage levels and absolute and relative inequalities at each time point; compare the relative contributions of inequalities before and during pregnancy to inequalities at birth; and examine associations between inequalities and coverage levels. We present the findings for countries individually and on aggregate, by World Bank country income grouping, as well as by maternal and neonatal tetanus elimination status, finding that most of the inequality in tetanus immunization coverage at birth is introduced during pregnancy. Inequalities in coverage during pregnancy are most pronounced in low- and lower-middle-income countries, and even more so in countries which have not achieved maternal and neonatal tetanus elimination. These findings suggest that pregnancy is a key time of opportunity for equity-oriented interventions to improve maternal tetanus immunization coverage.

Child immunization status according to number of siblings and birth order in 85 low- and middle-income countries: a cross-sectional study.

Background: Identification of unvaccinated children is important for preventing deaths due to infections. Number of siblings and birth order have been postulated as risk factors for zero-dose prevalence. Methods: We analysed nationally representative cross-sectional surveys from 85 low and middle-income countries (2010-2020) with information on immunisation status of children aged 12-35 months. Zero-dose prevalence was defined as the failure to receive any doses of DPT (diphtheria-pertussis-tetanus) vaccine. We examined associations with birth order and the number of siblings, adjusting for child's sex, maternal age and education, household wealth quintiles and place of residence. Poisson regression was used to calculate zero-dose prevalence ratios. Findings: We studied 375,548 children, of whom 13.7% (n = 51,450) were classified as zero-dose. Prevalence increased monotonically with birth order and with the number of siblings, with prevalence increasing from 11.0% for firstborn children to 17.1% for birth order 5 or higher, and from 10.5% for children with no siblings to 17.2% for those with four or more siblings. Adjustment for confounders attenuated but did not eliminate these associations. The number of siblings remained as a strong risk factor when adjusted for confounders and birth order, but the reverse was not observed. Among children with the same number of siblings, there was no clear pattern in zero-dose prevalence by birth order; for instance, among children with two siblings, the prevalence was 13.0%, 14.7%, and 13.3% for firstborn, second, and third-born, respectively. Similar results were observed for girls and boys. 9513 families had two children aged 12-35 months. When the younger sibling was unvaccinated, 61.9% of the older siblings were also unvaccinated. On the other hand, when the younger sibling was vaccinated, only 5.9% of the older siblings were unvaccinated. Interpretation: The number of siblings is a better predictor than birth order in identifying children to be targeted by immunization campaigns. Zero-dose children tend to be clustered within families. Funding: Gavi, the Vaccine Alliance.

Towards a better tomorrow: addressing intersectional gender power relations to eradicate inequities in maternal health.

An equity lens to maternal health has typically focused on assessing the differences in coverage and use of healthcare services and critical interventions. While this approach is important, we argue that healthcare experiences, dignity, rights, justice, and well-being are fundamental components of high quality and person-centred maternal healthcare that must also be considered. Looking at differences across one dimension alone does not reflect how fundamental drivers of maternal health inequities-including racism, ethnic or caste-based discrimination, and gendered power relations-operate. In this paper, we describe how using an intersectionality approach to maternal health can illuminate how power and privilege (and conversely oppression and exclusion) intersect and drive inequities. We present an intersectionality-informed analysis on antenatal care quality to illustrate the advantages of this approach, and what is lost in its absence. We reviewed and mapped equity-informed interventions in maternal health to existing literature to identify opportunities for improvement and areas for innovation. The gaps and opportunities identified were then synthesised to propose recommendations on how to apply an intersectionality lens to maternal health research, programmes, and policies.

A composite index; socioeconomic deprivation and coverage of reproductive and maternal health interventions.

Objective: To examine inequalities in the coverage of reproductive and maternal health interventions in low- and middle-income countries and territories using a composite index of socioeconomic deprivation status. Methods: We obtained data on education and living standards from national household surveys conducted between 2015 and 2019 to calculate socioeconomic deprivation status. We assessed the coverage of reproductive and maternal health interventions, using three indicators: (i) demand for family planning satisfied with modern methods; (ii) women who received antenatal care in at least four visits; and (iii) the presence of a skilled attendant at delivery. Absolute and relative inequalities were evaluated both directly and using the slope index of inequality and the concentration index. Findings: In the 73 countries and territories with available data, the median proportions of deprivation were 41% in the low-income category, 11% in the lower-middle-income category and less than 1% in the upper-middle-income category. The coverage analysis, conducted for 48 countries with sufficient data, showed consistently lower median coverage among deprived households across all health indicators. The coverage of skilled attendant at delivery showed the largest inequalities, where coverage among the socioeconomically deprived was substantially lower in almost all countries. Antenatal care visits and demand for family planning satisfied with modern methods also showed significant disparities, favouring the less deprived population. Conclusion: The findings highlight persistent disparities in the coverage of reproductive and maternal health interventions, requiring efforts to reduce those disparities and improve coverage, particularly for skilled attendant at delivery.

Identifying and Characterizing the Poorest Urban Population Using National Household Surveys in 38 Cities in Sub-Saharan Africa.

Identifying and classifying poor and rich groups in cities depends on several factors. Using data from available nationally representative surveys from 38 sub-Saharan African countries, we aimed to identify, through different poverty classifications, the best classification in urban and large city contexts. Additionally, we characterized the poor and rich groups in terms of living standards and schooling. We relied on absolute and relative measures in the identification process. For absolute ones, we selected people living below the poverty line, socioeconomic deprivation status and the UN-Habitat slum definition. We used different cut-off points for relative measures based on wealth distribution: 30%, 40%, 50%, and 60%. We analyzed all these measures according to the absence of electricity, improved drinking water and sanitation facilities, the proportion of children out-of-school, and any household member aged 10 or more with less than 6 years of education. We used the sample size, the gap between the poorest and richest groups, and the observed agreement between absolute and relative measures to identify the best measure. The best classification was based on 40% of the wealth since it has good discriminatory power between groups and median observed agreement higher than 60% in all selected cities. Using this measure, the median prevalence of absence of improved sanitation facilities was 82% among the poorer, and this indicator presented the highest inequalities. Educational indicators presented the lower prevalence and inequalities. Luanda, Ouagadougou, and N'Djaména were considered the worst performers, while Lagos, Douala, and Nairobi were the best performers. The higher the human development index, the lower the observed inequalities. When analyzing cities using nationally representative surveys, we recommend using the relative measure of 40% of wealth to characterize the poorest group. This classification presented large gaps in the selected outcomes and good agreement with absolute measures.

Maternal mental health and offspring's IQ: Evidence from two Brazilian birth cohorts.

Maternal mental health during different stages of life can have a significant impact on a child's cognitive development. This study aimed to investigate the association between maternal CMD at two distinct stages of the offspring's life (at 3 months and 11 years) and their IQ scores at 6 and 18 years across two birth cohorts. The study utilized data from two Brazilian birth cohorts: the 1993 cohort (full sample: N = 3719, subsample: N = 436), and the 2004 Pelotas Birth Cohort (N = 3440). IQ assessments were conducted at ages 18 and 6, employing the Wechsler Adult Intelligence Scale, third version (WAIS-III), and Wechsler Intelligence Scale for Children, third version (WISC-III), respectively. The presence of maternal CMD at 3 months and 11 years of age was evaluated using the Brazilian version of the Self-Reporting Questionnaire (SRQ-20). After adjustment, participants whose mothers experienced CMD at 3 months had average IQ scores 1.74 (95 % CI: -2.83 to -0.67) and 2.79 (95 % CI: -5.54 to -0.04) points lower at ages 6 (2004 cohort) and 18 (1993 cohort subsample), respectively. Furthermore, in the 1993 cohort (both full and subsample), maternal CMD at 11 years was associated with lower IQ scores at age 18. Understanding the mechanisms underlying this association, emphasized by these findings, is crucial for promoting children's cognitive development, educational achievement, and overall well-being.

Evaluation of genomic factors and early childhood stimulation on intelligence in children from a Brazilian birth cohort: The primary role of independent factors.

BACKGROUND: Childhood cognitive abilities are a predictor of health outcomes and adult income potential. Identifying factors associated with childhood intelligence and their interactions is essential in behavioral research. We assessed the impact of genetic variants and early child stimulation (ECS) on child intelligence and examined their possible interaction as potential modifiers of IQ in a population-based longitudinal study. METHODS: Participants of the 2004 Pelotas Birth Cohort study (N = 4231) underwent intelligent quotient (IQ) by WISC-III assessment at 6 years of age. At 24 and 48-months, mothers answered five ECS marker questions, whose sum was used to create a score. The polygenic score for intelligence (IQ-PGS) was constructed from the GWAS-weighted estimate of cognition. Association was assessed using multiple linear regression models adjusted for maternal, family, and child confounding variables. To explore the possible influence of skin color and ethnoracial classification, the regression models were stratified according to the skin color variable, as a sensitivity analysis. RESULTS: In the adjusted analysis, IQ-PGS (ß = 0.79, 95% confidence interval [95% CI] 0.26;1.31) as well as ECS (ß = 2.34; 95% CI: 1.76;2.92) were associated with IQ in this sample. The association between IQ-PGS and IQ was significant only in the white Brazilian group in the sensitivity analysis. However, there was no interaction between IQ-PGS and ECS on IQ (p(IQ-PGS x ECS) = 0.46). CONCLUSIONS: ECS did not modify the impact of genetic potential on intellectual development during childhood, suggesting that genetic factors and ECS exert independent effects on the IQ levels of children.

Accelerometer-based sleep metrics and gut microbiota during adolescence: Association findings from a Brazilian population-based birth cohort.

BACKGROUND: Sleep and gut microbiota are emerging putative risk factors for several physical, mental, and cognitive conditions. Sleep deprivation has been shown to be linked with unhealthy microbiome environments in animal studies. However, in humans, the results are mixed. Epidemiological studies evaluating the effect of accelerometer-based sleep measures on gut microbiome are scarce. This study aims to explore the relationship between sleep duration and efficiency with the gut microbiota in adolescence. METHODS: A subsample of 352 participants from the 2004 Pelotas (Brazil) Birth Cohort Study with sleep and fecal microbiota data available were included in the study. Sleep duration and sleep efficiency were obtained from actigraphy information at 11 years old whereas microbiota information from fecal samples was collected at 12 years. The fecal microbiota was analyzed via Illumina MiSeq (16S rRNA V3-V4 region) and the UNOISE pipeline. Alpha was assessed in QIIME2. Association measures for sleep variables and microbial α-diversity, and bacterial relative abundance were assessed through generalized models (linear and logistic regression), adjusting for maternal and child variables confounders. RESULTS: Adjusted models showed that sleep duration was positively associated with Simpson index of α-diversity (ß = 0.003; CI95 %: 0.00004; 0.01). Both sleep duration (OR = 0.43; CI95 % 0.25; 0.74) and efficiency (OR = 0.55; CI95 % 0.38; 0.78) were associated with lower Bacteroidetes abundance. CONCLUSION: Our results suggest that sleep duration and efficiency are linked to gut microbiota diversity and composition even with 1-2 years gap from exposure to outcome. The findings support the role of sleep in the gut-brain axis as well as provide insights on how to improve microbiota health.

Cross-sectional and prospective associations between screen time and childhood neurodevelopment in two Brazilian cohorts born 11 years apart.

BACKGROUND: The aim of this study was to investigate the associations between screen time from ages 2 to 4 years and child neurodevelopment at age 4. METHODS: The participants were from the 2004 (N = 3787) and 2015 (N = 3604) Pelotas (Brazil) birth cohort studies. Childhood neurodevelopment was assessed at age 4 using the Battelle Development Inventory. The time children spent on screen devices was reported by their guardians at ages 2 and 4 years. Linear regression models were used to investigate the association of: (i) time spent on television at ages 2 and 4 years; (ii) time spent on other screens at age 4; and (iii) total screen time at age 4 (television + other screens) with childhood neurodevelopment at age 4. RESULTS: Average daily screen time among children born in 2004 and those born in 2005 aged 4 years were 3.4 (SD: 2.4) and 4.4 h (SD: 2.9), respectively. Overall, few associations of very small magnitude between screen time and child neurodevelopment were observed. Television time at 2 years of age was statistically associated with lower neurodevelopment at 4 years of age in the 2015 cohort (ß = -0.30, 95%CI = -0.55; -0.05). Conversely, television time (ß = 0.17, 95%CI = 0.07, 0.26) and total screen time (ß = 0.22, 95%CI = 0.13, 0.31) at age 4 were associated with higher neurodevelopment at age 4 in the 2004 cohort. CONCLUSIONS: The findings of this study suggest that the amount of time spent on screen devices might not be associated with neurodevelopment of children under 5 years of age. The small magnitude and inconsistencies in the direction of associations did not find evidence to support the current guidelines for screen time at this age. Therefore, more studies, especially those with longitudinal data, are important to comprehend the true effect of screen time on neurodevelopment and other health outcomes.

Perception of parents and caregivers about the need for dental appointments for adolescents from a Brazilian birth cohort.

OBJECTIVE: To investigate the perception of parents or caregivers regarding the need for dental appointments for adolescents aged 12-13 years and associated factors. METHODS: Data from the Pelotas 2004 Birth Cohort were used. The outcome variable was the need for dental appointments for young adolescents perceived by parents or caregivers. Demographic and economic exposure variables were obtained from the first (2004) and sixth general follow-up (2015), respectively. The exposure variables 'previous history of dental pain', 'self-rated oral health', clinical variables and the outcome variable were obtained from the second oral health follow-up (2017). Unadjusted and adjusted multivariate Poisson regression analyses provided prevalence ratios (PR) and respective 95% confidence intervals (CI). RESULTS: At the first oral health follow-up (2009), 1303 five-year-old children were recruited, 996 of whom were reassessed and underwent oral health examinations at 12 and 13 years of age (response rate: 76.4%). The findings showed that 72.4% of parents/caregivers perceived that the adolescents needed dental appointments. No associations were found between the outcome and sociodemographic or economic variables. After adjustments, the outcome remained positively associated with previous history of toothache (PR 1.22; 95% CI 1.14-1.32), self-rated oral health as fair or poor (PR 1.26; 95% CI 1.15-1.39), the presence of dental caries (PR 1.27; 95% CI 1.20-1.38) and severe or disabling malocclusion (PR 1.14; 95% CI 1.05-1.25). CONCLUSIONS: The perception of parents/caregivers regarding the need for dental appointments on the part of their adolescent sons and daughters was associated with oral health problems, and these findings can serve as the basis for creating and improving oral health programmes that seek a better understanding on the part of parents and caregivers regarding the importance of integral care for their adolescent children.