Summary: New analysis links childhood poverty and exposure to stressful life events with a higher risk of externalizing mental health disorders during adolescence and early adulthood, with effects especially pronounced among females.
Source: FAPESP
A cohort study published in European Child & Adolescent Psychiatry finds a clear association between early-life poverty and a greater likelihood of developing externalizing disorders in adolescence and young adulthood, particularly for girls.
Externalizing disorders are psychiatric conditions marked by behaviors such as aggression, impulsivity, rule-breaking, and attention-deficit/hyperactivity symptoms. These problems often impair learning, relationships, and future employment prospects.
Researchers conclude that multidimensional poverty and repeated exposure to stressful life events—such as family conflict and bereavement—operate as modifiable risk factors. Addressing these conditions in childhood could reduce the long-term burden of mental health problems. The study evaluated multiple socioeconomic indicators, including parental education, access to basic services, housing quality, and household infrastructure.
The analysis followed 1,590 students from public schools in Porto Alegre and São Paulo over roughly seven years, with assessments at three points, the last occurring in 2018–2019. These participants are a subset of the Brazilian High-Risk Cohort Study for Childhood Psychiatric Disorders (BHRC), a large community-based project that began in 2010 with 2,511 families of children aged 6–10.
Led by the National Institute of Developmental Psychiatry and supported by FAPESP and CNPq, the BHRC—also called Project Connection—Minds of the Future, is among Brazil’s most extensive studies of child and adolescent mental health. Its principal investigator is Eurípedes Constantino Miguel Filho of the University of São Paulo’s Medical School. The project involves more than 80 researchers from over 20 institutions.
“While it might seem intuitive that poverty contributes to mental health problems, this study is unique in Brazil for using repeated psychiatric assessments to track developmental trajectories from childhood into early adulthood,” said Carolina Ziebold, the study’s lead author and a researcher at the Federal University of São Paulo (UNIFESP). The repeated measures allowed the team to observe how disorder rates changed over time rather than relying on a single snapshot.
Psychiatric diagnoses were determined using the Development and Well-Being Assessment (DAWBA), a validated set of interviews and questionnaires administered at mean ages 9.7, 13.5 and 18.2 years. The researchers aimed to identify both internalizing disorders (for example, depression and anxiety) and externalizing disorders, finding the strongest effects for the latter.
Socioeconomic status was measured with a standardized instrument tailored for the cohort; 11.4% of participants were classified as living in poverty at baseline. Longitudinal modeling showed that, although children from poorer households initially displayed lower levels of externalizing disorders than their better-off peers, their risk rose over time. By adolescence and early adulthood, the probability of developing externalizing disorders reached roughly 63% among those from poor backgrounds, while it declined among non-poor participants.
Gender differences
When the researchers stratified the data by sex, they observed a pronounced gender disparity: the association between childhood poverty and later externalizing disorders was strongest and statistically significant among females. This stood out because externalizing disorders are typically more common in males.
Ziebold and colleagues propose several explanations. Mental health problems in girls from impoverished backgrounds may go undetected in family and school settings, delaying diagnosis and treatment. Additionally, girls often take on more caregiving and domestic responsibilities early in life—looking after younger siblings or sick relatives—which increases their exposure to stressful experiences. This cumulative burden may escalate the risk of developing psychiatric disorders as they transition to adulthood.
The study group’s earlier work using the same cohort linked externalizing disorders to poorer educational outcomes for girls, including grade repetition and school dropout. Their analysis suggests that preventing or treating these disorders could reduce age-grade distortion: an estimated ten out of every 100 overage girls might have remained on track with their peers, and five fewer girls would have repeated a grade.
“Children and young adults with externalizing disorders often face setbacks in learning, social development and employment, which can perpetuate poverty into adulthood,” Ziebold noted. International comparisons highlight the challenge in Brazil: intergenerational educational mobility is low, meaning children whose parents have limited schooling are far more likely to repeat that pattern.
Labor market outcomes are tightly linked to parental education: children of degree-holders are substantially more likely to obtain highly skilled, well-paid jobs than children whose parents have little formal education.
Pandemic context and policy implications
Given the long-term effects of externalizing disorders on health, education and employment, the findings underscore the importance of early anti-poverty and prevention programs. Ziebold emphasizes a multidimensional response: short-term measures such as cash transfers, fee waivers and income support are vital, but so are investments in socio-emotional skill building, stress reduction programs, access to quality education, and accessible mental health services for children and adolescents.
The COVID-19 pandemic has exacerbated the problem. UNICEF reports that multidimensional child poverty increased globally during the pandemic, with an estimated 100 million more children falling into poverty since 2019. The crisis also disrupted mental health services in most countries, compounding risks for young people and lengthening the time required to return to pre-pandemic levels of child well-being.
About this poverty and mental health research news
Author: Luciana Constantino
Source: FAPESP
Contact: Luciana Constantino – FAPESP
Image: The image is in the public domain
Original Research: Closed access.
“Childhood poverty and mental health disorders in early adulthood: evidence from a Brazilian cohort study” by Carolina Ziebold et al. European Child & Adolescent Psychiatry
Abstract
Childhood poverty and mental health disorders in early adulthood: evidence from a Brazilian cohort study
Background
This study examined links between childhood poverty and mental health disorders from childhood into early adulthood. It also tested whether exposure to stressful life events mediates the relationship between early poverty and later psychiatric outcomes.
Methods
Data came from a prospective community cohort assessed at baseline (mean age 9.7), first follow-up (mean 13.5) and second follow-up (mean 18.2), with 1,590 participants included. Poverty was measured by a standardized classification; exposure to 20 types of stressful life events was recorded via a Life History instrument. Psychiatric diagnoses were obtained using the Development and Well-Being Assessment. Latent growth models evaluated how baseline poverty predicted trajectories of any mental health disorder, externalizing disorders and internalizing disorders. Mediation analyses tested whether stressful life events explained links between childhood poverty and disorders in early adulthood.
Results
At baseline, 11.4% of the sample lived in poverty. Childhood poverty predicted a greater tendency to develop externalizing disorders in adolescence and early adulthood (standardized estimate = 0.27, p = 0.016); associations with any disorder or internalizing disorders were not significant. Poverty raised the likelihood of externalizing disorders in early adulthood partly through increased exposure to stressful life events (OR = 1.07, 95% CI 1.01–1.14). In sex-stratified analyses, results were replicated only among females.
Conclusions
Childhood poverty negatively affected trajectories of externalizing mental health disorders during adolescence, particularly among girls. Both poverty and exposure to stressful life events are preventable risk factors; addressing them could reduce the burden of externalizing disorders in young people and improve long-term social and health outcomes.