Does early nutrition predict cognitive skills during later childhood? Evidence from two developing countries.

The existing evidence linking early undernutrition to educational outcomes in developing countries is largely focused on assessing its impacts on grade attainment and achievement test scores, with limited evidence on the foundational cognitive skills required to perform well at school. We use unique data collected in Ethiopia and Peru as part of the Young Lives Study to investigate the relationship between early undernutrition and four foundational cognitive skills measured later in childhood, the first two of which measure executive functioning: working memory, inhibitory control, long-term memory, and implicit learning. We exploit the rich longitudinal data available to control for potential confounders at the household and individual level and for time-invariant community characteristics. We also take advantage of the availability of data for paired-siblings to obtain household fixed-effects estimates. In the latter specification, we find robust evidence that stunting at ~ age 5 is negatively related with executive functions measured years later, predicting reductions in working memory and inhibitory control by 12.6% and 5.8% of a standard deviation. Although the main cohort of Young Lives was around 12 years old when executive functions were measured, complementary results and analysis of the data available for the younger siblings suggest that the impact of stunting on executive functions-specifically, on working memory-starts at an earlier age. Our results shed light on the mechanisms that explain the relationship between early nutrition and school achievement tests suggesting that good nutrition is an important determinant of children's learning capacities.

Social Protection and Foundational Cognitive Skills during Adolescence: Evidence from a Large Public Works Program.

Many low- and middle-income countries have introduced public works programs (PWPs) to fight poverty. This paper provides the first evidence that children from families who benefit from PWPs show increased foundational cognitive skills. The results, based on unique tablet-based data collected as part of a long-standing longitudinal survey, show positive associations between participation in the Productive Safety Net Programme (PSNP) in Ethiopia during childhood with long-term memory and implicit learning, and suggestive evidence for working memory. These associations appear to be strongest for children whose households were still PSNP participants in the year of data collection. Evidence suggests that the association with implicit learning may be operating partially through children's time reallocation away from unpaid labor responsibilities, while the association with long-term memory may in part be due to the program's success in remediating nutritional deficits caused by early-life rainfall shocks.

Late-childhood foundational cognitive skills predict educational outcomes through adolescence and into young adulthood: evidence from Ethiopia and Peru.

We estimate associations between foundational cognitive skills (inhibitory control, working memory, long-term memory, and implicit learning) measured at age 12 and educational outcomes measured at ages 15 and 19-20 in Ethiopia and Peru, using the Young Lives data. The estimates adjust for rich sets of controls and include measurements of children's baseline abilities. For a subset of the outcomes, we exploit within-household variation. Working memory and long-term memory are consistently and positively associated with subsequent domain-specific cognitive achievement tests (measuring specifically numeracy, vocabulary and literacy achievement) in both countries, university enrolment in Peru (long-term memory) and lower secondary-school completion in Ethiopia (working memory). Inhibitory control predicts subsequent math-test scores in both countries, grade attainment (Ethiopia), and university enrolment (Peru). Value-added estimates show that these skills play roles during adolescence, with the memory-related skills predicting higher domain-specific test scores (Peru and Ethiopia) and grade attainment (Ethiopia), while inhibitory control has associations with math (both countries). These results provide additional evidence to justify the importance of promoting investments in cognitive skills throughout childhood and adolescence, and elucidate how such investments impact educational achievements.

Long-term effects of early life rainfall shocks on foundational cognitive skills: Evidence from Peru.

Global warming is changing precipitation patterns, particularly harming communities in low-and-middle income countries (LMICs). Whilst the long-term effects of being exposed to rainfall shocks early in life on school-achievement tests are well-established, there is little population-based evidence from LMICs on the mechanisms through which these shocks operate. Executive functions (EFs) are key for children's learning abilities. This paper analyses the effects of early exposure to rainfall shocks on four foundational cognitive skills (FCSs), including EFs that have been found to be key predictors of educational success. These skills were measured via a series of tablet-based tasks administered in Peru as part of the Young Lives longitudinal study (YLS). We combine the YLS data with gridded data on monthly precipitation to generate monthly, community-level rainfall shock estimates. The key identification strategy relies on temporary climatic shocks being uncorrelated with other latent determinants of FCSs development. Our results show significant negative effects of early life exposure to rainfall shocks on EFs-especially, on working memory-measured in later childhood. We also find evidence of rainfall shocks decreasing households' abilities to invest in human capital, which may affect both FCSs and domain-specific test scores. Finally, there is suggestive, but not conclusive, evidence that a conditional-cash-transfer program providing poor households with additional financial resources might partially offset the effects of the rainfall shocks.

Interactions between genetic and lifestyle factors on cardiometabolic disease-related outcomes in Latin American and Caribbean populations: A systematic review.

Introduction: The prevalence of cardiometabolic diseases has increased in Latin American and the Caribbean populations (LACP). To identify gene-lifestyle interactions that modify the risk of cardiometabolic diseases in LACP, a systematic search using 11 search engines was conducted up to May 2022. Methods: Eligible studies were observational and interventional studies in either English, Spanish, or Portuguese. A total of 26,171 publications were screened for title and abstract; of these, 101 potential studies were evaluated for eligibility, and 74 articles were included in this study following full-text screening and risk of bias assessment. The Appraisal tool for Cross-Sectional Studies (AXIS) and the Risk Of Bias In Non-Randomized Studies-of Interventions (ROBINS-I) assessment tool were used to assess the methodological quality and risk of bias of the included studies. Results: We identified 122 significant interactions between genetic and lifestyle factors on cardiometabolic traits and the vast majority of studies come from Brazil (29), Mexico (15) and Costa Rica (12) with FTO, APOE, and TCF7L2 being the most studied genes. The results of the gene-lifestyle interactions suggest effects which are population-, gender-, and ethnic-specific. Most of the gene-lifestyle interactions were conducted once, necessitating replication to reinforce these results. Discussion: The findings of this review indicate that 27 out of 33 LACP have not conducted gene-lifestyle interaction studies and only five studies have been undertaken in low-socioeconomic settings. Most of the studies were cross-sectional, indicating a need for longitudinal/prospective studies. Future gene-lifestyle interaction studies will need to replicate primary research of already studied genetic variants to enable comparison, and to explore the interactions between genetic and other lifestyle factors such as those conditioned by socioeconomic factors and the built environment. The protocol has been registered on PROSPERO, number CRD42022308488. Systematic review registration: https://clinicaltrials.gov, identifier CRD420223 08488.

The origins of cognitive skills and non-cognitive skills: The long-term effect of in-utero rainfall shocks in India.

Skills are an important predictor of labour, education, and wellbeing outcomes. Understanding the origins of skills formation is important for reducing future inequalities. This paper analyses the effect of shocks in-utero on human capital outcomes in childhood and adolescence in India. Combining historical rainfall data and longitudinal data from Young Lives, we estimate the effect of rainfall shocks in-utero on cognitive and non-cognitive skills development over the first 15 years of life. We find negative effects of rainfall shocks on receptive vocabulary at age 5, and on mathematics and non-cognitive skills at age 15. The negative effects on cognitive skills are driven by boys, while the effect for both cognitive and non-cognitive skills are driven by children of parents with lower education, suggesting that prenatal shocks might exacerbate pre-existing inequalities. Our findings support the implementation of policies aiming at reducing inequalities at very early stages in life.

The evolution of young people's mental health during COVID-19 and the role of food insecurity: Evidence from a four low-and-middle-income-country cohort study.

OBJECTIVES: Provide evidence on how young people's mental health has evolved in Low-and-Middle-Income-Countries (LMICs) during the progression of the COVID-19 pandemic. Identify particularly vulnerable groups who report high and/or continuously high rates of mental health issues. STUDY DESIGN: Longitudinal, observational. METHODS: Two consecutive phone-surveys (August-October and November-December 2020) in Ethiopia, India, Peru and Vietnam interviewed around 9000 participants of a 20-year cohort study who grew up in poverty, now aged 19 and 26. Rates of at least mild anxiety/depression measured by GAD-7/PHQ-8 were each compared across countries; between males/females, and food secure/food insecure households. RESULTS: Overall, rates of at least mild anxiety and mild depression significantly decreased between mid and end-2020 in all countries but Ethiopia as COVID-19 infection rates fell. Females report higher rates of anxiety and depression in all countries but Ethiopia, however the gender gap is closing. Young people in food insecure households have not shown consistent improvements in their rates of anxiety and depression. Food insecure households are poorer, and have significantly more children (p < 0.05) except in Ethiopia. CONCLUSION: Food insecurity is negatively associated with young people's mental health and urgent support targeted towards the most vulnerable should be a priority. Further research into increasing rates of mental health issues in Ethiopia is needed.

Development of an online food frequency questionnaire and estimation of misreporting of energy intake during the COVID-19 pandemic among young adults in Peru.

Background: The Young Lives longitudinal study switched to remote data collection methods including the adaptation of dietary intake assessment to online modes due to the physical contact restrictions imposed by the COVID-19 pandemic. This study aimed to describe the adaptation process and validation of an online quantitative food frequency questionnaire (FFQ) for Peruvian young adults. Methods: A previously validated face-to-face FFQ for the adult Peruvian population was adapted to be administered through an online self-administered questionnaire using a multi-stage process. Questionnaire development was informed by experts' opinions and pilot surveys. FFQ validity was assessed by estimating misreporting of energy intake (EI) using the McCrory method, and the FFQ reliability with Cronbach alpha. Logistic regressions were used to examine associations of misreporting with sociodemographic, body mass index (BMI), and physical activity covariates. Results: The FFQ was completed by 426 Peruvian young adults from urban and rural areas, among whom 31% were classified as misreporters, with most of them (16.2%) overreporting daily EI. Men had a lower risk of under-reporting and a higher risk of over-reporting (OR = 0.28 and 1.89). Participants without a higher education degree had a lower risk of under-reporting and a higher risk of over-reporting (OR = 2.18 and 0.36, respectively). No major difference in misreporting was found across age groups, areas, studying as the main activity, being physically active or sedentary, or BMI. Results showed good internal reliability for the overall FFQ (Cronbach alpha = 0.82). Conclusion: Misreporting of EI was mostly explained by education level and sex across participants. Other sociodemographic characteristics, physical activity, sedentary behavior, and BMI did not explain the differences in EI misreporting. The adapted online FFQ proved to be reliable and valid for assessing dietary intakes among Peruvian young adults during the COVID pandemic. Further studies should aim at using and validating innovative dietary intake data collection methods, such as those described, for informing public health policies targeting malnutrition in different contexts after the COVID-19 pandemic.

The impact of COVID-19 lockdowns on physical domestic violence: Evidence from a list randomization experiment.

We quantify the increase in physical domestic violence (family or intimate partner violence) experienced by young people aged 18-26 during the 2020 COVID-19 lockdowns in Peru. To do this we use an indirect methodology, the double list randomization experiment. The list experiment was embedded in a telephone survey to participants of the Young Lives study, a long-standing cohort survey. We find that 8.3% of the sample experienced an increase in physical violence within their households during the lockdown period. Those who had already reported experiencing domestic violence in the last round of (in-person) data collection in 2016 are more likely to have experienced increased physical violence during the COVID-19 lockdown, with 23.6% reporting an increase during this time. The reported increase in violence does not differ significantly by gender. List experiments, if carefully conducted, may be a relatively cheap and feasible way to elicit information about sensitive issues during a phone survey.

Impact of the COVID-19 pandemic on anxiety and depression symptoms of young people in the global south: evidence from a four-country cohort study.

OBJECTIVE: To provide evidence on the effect of the COVID-19 pandemic on the mental health of young people who grew up in poverty in low/middle-income countries (LMICs). DESIGN: A phone survey administered between August and October 2020 to participants of a population-based longitudinal cohort study established in 2002 comprising two cohorts born in 1994-1995 and 2001-2002 in Ethiopia, India (Andhra Pradesh and Telangana), Peru and Vietnam. We use logistic regressions to examine associations between mental health and pandemic-related stressors, structural factors (gender, age), and lifelong protective/risk factors (parent and peer relationship, wealth, long-term health problems, past emotional problems, subjective well-being) measured at younger ages. SETTING: A geographically diverse, poverty-focused sample, also reaching those without mobile phones or internet access. PARTICIPANTS: 10 496 individuals were approached; 9730 participated. Overall, 8988 individuals were included in this study; 4610 (51%) men and 4378 (49%) women. Non-inclusion was due to non-location or missing data. MAIN OUTCOME MEASURES: Symptoms consistent with at least mild anxiety or depression were measured by Generalized Anxiety Disorder-7 (≥5) or Patient Health Questionnaire-8 (≥5). RESULTS: Rates of symptoms of at least mild anxiety (depression) were highest in Peru at 41% (32%) (95% CI 38.63% to 43.12%; (29.49-33.74)), and lowest in Vietnam at 9% (9%) (95% CI 8.16% to 10.58%; (8.33-10.77)), mirroring COVID-19 mortality rates. Women were most affected in all countries except Ethiopia. Pandemic-related stressors such as health risks/expenses, economic adversity, food insecurity, and educational or employment disruption were risk factors for anxiety and depression, though showed varying levels of importance across countries. Prior parent/peer relationships were protective factors, while long-term health or emotional problems were risk factors. CONCLUSION: Pandemic-related health, economic and social stress present significant risks to the mental health of young people in LMICs where mental health support is limited, but urgently needed to prevent long-term consequences.

Role of Government Financial Support and Vulnerability Characteristics Associated with Food Insecurity during the COVID-19 Pandemic among Young Peruvians.

Peruvian households have experienced one of the most prevalent economic shocks due to COVID-19, significantly increasing their vulnerability to food insecurity (FI). To understand the vulnerability characteristics of these households among the Peruvian young population, including the role of the government's response through emergency cash transfer, we analysed longitudinal data from the Young Lives study (n = 2026), a study that follows the livelihoods of two birth cohorts currently aged 18 to 27 years old. FI was assessed using the Food Insecurity Experience Scale. Household characteristics were collected before and during the COVID-19 outbreak in Peru to characterise participants' vulnerability to FI. Multivariate logistic regression was used to evaluate the association between government support and participants' vulnerability characteristics to FI. During the period under study (March to December 2020), 24% (95% CI: 22.1-25.9%) of the participants experienced FI. Families in the top wealth tercile were 49% less likely to experience FI. Larger families (>5 members) and those with increased household expenses and decreased income due to COVID-19 were more likely to experience FI (by 35%, 39% and 42%, respectively). There was no significant association between government support and FI (p = 0.768). We conclude that pre-pandemic socioeconomic status, family size, and the economic disruption during COVID-19 contribute to the risk of FI among the Peruvian young population, while government support insufficiently curtailed the risk to these households.