Economic Inequalities and the Social Determinants of Psychopathology
Recap of Biological and Early-Life Factors
There is substantial evidence that psychopathology is influenced by genetic factors. A key phenomenon in this area is pleiotropy, where there is significant overlap in genetic variants across different forms of psychopathology. In addition to genetics, early environmental ‘insults’ are critically related to the development of psychopathology. These insults occur during critical early development periods, including the prenatal environment. Specific examples of these early-life stressors include:
Maternal infection during pregnancy.
Alcohol use during pregnancy.
Prenatal stress.
Exposure to pollution.
These factors are assumed to have a direct impact on brain development, creating cascading effects that persist across the individual’s lifespan. While biological emphasis is common, it is essential to consider the broader systemic factors influencing health.
Introduction to Public Health and Social Determinants
Mental health is fundamentally a public health issue. The public health approach focuses on three pillars: prevention, promotion, and protection. Mental health is categorized alongside other major public health concerns, such as non-communicable diseases, infectious diseases, reproductive and sexual health, and obesity or malnutrition. Because these are significant issues at scale, it is necessary to examine determinants at scale, focusing on non-medical and social determinants ranging from local to international levels.
Social determinants are the social, economic, and physical conditions that influence health at both the individual and societal levels. These include:
Economic factors (e.g., income and wealth).
Neighborhood environments.
Protected characteristics.
Social support and inclusion.
Exposure to adversity (Alegria et al., 2018; Kirkbride et al., 2024).
Key perspectives on social determinants include:
Life Course Perspective: Adversity is not restricted to childhood; its effects are cumulative across the lifespan.
Intergenerational Impact: Determinants can affect outcomes across generations.
Intersectionality: Individuals hold multiple social identities that interact to influence health risk.
Modifiability: Many social determinants are structural and therefore capable of being changed through policy.
Health Inequalities and the Social Gradient
Health inequalities are defined as avoidable, unfair, and systematic inequalities in social determinants (risk or protective factors), health disparities, access to services, and the quality and experience of support. There is a reciprocal relationship between health and social determinants, where health impacts choices and circumstances, which in turn can widen mental health inequalities and increase risk.
According to the Mental Health Foundation (2020): ‘The likelihood of our developing a mental health problem is influenced by our biological makeup, and by the circumstances in which we are born, grow, live and age. Those who face the greatest disadvantages in life also face the greatest risks to their mental health. This unequal distribution of risk to our mental health is what we call mental health inequalities.’
Central to this is the Social Gradient, which dictates that lower social status is linked to worse health outcomes, including psychopathology. This occurs across a social spectrum, and the impact accumulates over time (Alegria et al., 2018; Kirkbride et al., 2024).
Economic Inequalities: The Impact of Low Income
Economic inequality is a multifaceted concept. ‘Poverty’ can be defined in multiple ways, such as a low income that is well below the national average (often referred to as the ‘poverty level’ or ‘poverty line’). Researchers use multiple economic indicators to assess this, including income inequalities within an area, food insecurity, employment status, education level, and socioeconomic status (a combination of these factors).
Low household income during childhood (childhood poverty) is strongly associated with:
Emotional and behavioural problems.
Dimensional psychopathology.
Depression and anxiety.
Recurrent issues from childhood into young adulthood (Chau et al., 2025; Fitzsimons et al., 2017; Najman et al., 2011; Zilanawala et al., 2019).
The impact is worse when exposure is persistent or cumulative. There is also an ongoing discussion regarding whether income inequality becomes more impactful at an age where it is actively noticed by the individual. In low and middle-income countries, household income alone may not be the most important indicator; multiple overlapping indicators are often required for an accurate assessment.
Area-Based Income Inequality and the Gini Coefficient
Beyond household income, researchers look at ‘relative income’ rather than just ‘absolute poverty.’ This is often measured using the Gini coefficient, which represents income inequality within a specific area such as a neighborhood, city, or country. A higher Gini coefficient indicates greater income inequality, meaning more income is held by fewer people.
Higher area-based income inequality is associated with poorer mental health in adolescents and adults across various settings, including schools, neighborhoods, and states or counties (Benny et al., 2021; Farmer et al., 2022; Fone et al., 2018; Tibber et al., 2022; Vilhjalmsdottir et al., 2016). Interestingly, this effect is often not observed in very young children, suggesting a developmental lag before the psychological impacts of inequality manifest.
Importantly, these findings remain significant even when controlling for absolute deprivation, indicating that the psychological impact of inequality is not just about having basic needs unmet, but about the inequality itself.
The Psychological Costs of Inequality: The Inner Level
Richard Wilkinson and Kate Pickett, authors of The Spirit Level and The Inner Level, argue that unequal societies are worse for everyone, not just those at the bottom. Their research suggests that larger income differences in a society increase the prevalence of nearly all health and social problems that occur more frequently lower down the social ladder.
Key takeaways from Wilkinson and Pickett (2017):
Inequality fundamentally affects the quality of social relations.
Humans have two evolved social strategies: one adaptive for dominance hierarchies and one for egalitarian societies based on reciprocity and cooperation.
Material inequality shifts the balance toward dominance-based strategies, which increases the prevalence of various psychopathologies.
Food Insecurity and Psychopathology
Food insecurity is defined as a household’s lack of access to a sufficient amount of food, or a lack of nutritional and safe food required to maintain a healthy and active lifestyle. Statistics indicate that of UK households experience food insecurity, rising to among households with children. Globally, food insecurity affects approximately of the population.
Food insecurity is associated with:
Dimensional psychopathology.
Poor neurodevelopmental outcomes.
Specific diagnostic categories (Althoff et al., 2016; Lund et al., 2010; Romero et al., 2025; Smith et al., 2023; Thielman et al., 2024).
These associations exist over and above the effects of general poverty and income. Food insecurity can increase the burden on parents, which subsequently impacts child mental health. However, the direction of the relationship remains unclear, as psychopathology itself may lead to food insecurity.
Employment and Education as Determinants
Employment factors influencing mental health include being unemployed versus employed, loss of income (distinct from job loss), and job insecurity (precarious employment). Precarious employment involves the possibility of losing one’s job, difficulty finding work while unemployed, poor working conditions, or temporary work. Employment-related issues affect adult mental health and are linked to emotional difficulties in offspring. Re-employment has been found to be a protective factor.
Education is closely linked to economic disadvantage. Lower levels of education are associated with poorer mental health, particularly in low and middle-income countries. Parental education is also a predictor of offspring psychopathology from childhood through adolescence. Conversely, higher educational attainment serves as a protective factor against psychiatric disorders (Chua et al., 2025; Erickson et al., 2016; Straatmann et al., 2019).
Mechanisms and Theoretical Models
The mechanisms linking economic inequalities to psychopathology risk include both material and psychological pathways:
Unmet Basic Needs: Lack of food, shelter, or safety.
Social Disruption: Impact on social support, social cohesion, and trust.
Social Comparison: Also known as status anxiety; the psychological strain of comparing one's status to others in an unequal society.
Chronic Stress: Biological pathways activated by persistent environmental stressors.
Interconnectivity: Indicators of economic inequality often influence and exacerbate each other.
There is an ongoing debate between two primary models:
Social Causation: Higher exposure to multiple risk factors in disadvantaged environments causes mental health problems. This impact is cumulative and increases through adolescence.
Social Drift: Individuals with psychopathology may drift into adverse economic circumstances due to the functional impairment caused by their condition.
Evidence suggests the relationship is likely bidirectional: economic inequality increases the risk of psychopathology, and psychopathology impacts social determinants, causing inequalities to widen over time.
Environmental Injustice and Neurodevelopment
Environmental exposure disparities are often a consequence of structural racism. Low-income minoritized populations experience a disproportionate burden of hazardous exposures due to proximity to industrial facilities, high-traffic roads, and suboptimal housing. Research from has focused on exposures like air pollution, metal exposures, and water contamination.
Vulnerable populations are at double risk because they face a greater burden of exposure while having fewer resources to manage the associated expenses or access quality care. Reducing these exposures is critical for improving child development and overall public health (Dickerson et al., 2023).
Essential Reading and References
Essential Core Reading:
Thielman, J. et al. (2024). Cross-sectional analysis of household food insecurity and mental health in children aged in Canada. BMJ Open, 14(6).
Zilanawala, A. et al. (2019). Internalising and externalising behaviour profiles across childhood. Social Science & Medicine, 226, 207-216.
Recommended Reading:
Chua, Y. W. et al. (2025). Socioeconomic inequalities in mental health difficulties over childhood. Social Science & Medicine, 378.
Tibber, M. S. et al. (2022). The association between income inequality and adult mental health at the subnational level. Social Psychiatry and Psychiatric Epidemiology.
Further Reading:
Fitzsimons, E. et al. (2017). Poverty dynamics and parental mental health in the UK. Social Science & Medicine, 175, 43-51.
Najman, J. M. et al. (2010). Family poverty over the early life course and recurrent adolescent anxiety and depression. American Journal of Public Health, 100(9), 1719-1723.