Could Socioeconomic Status Help Explain Differences in Brain Function and Depression Treatment Outcomes?
January 19, 2026
Individuals with major depressive disorder do not all respond to treatment in the same way, and researchers are still working to understand why. A recent CAN-BIND study investigated whether socioeconomic status, primarily measured by household income, could help explain these differences.
What is Socioeconomic Status (SES)?
Socioeconomic status, or SES, refers to a person’s social and economic position in society, which is shaped by things like income, education, and job status. While previous research has shown that people with lower socioeconomic status are more likely to experience depression and may have poorer treatment outcomes, the biological and brain-based reasons for these differences are not very well understood.
“Despite SES being identified as a predictor of antidepressant response and studies showing that childhood SES influences brain structure and function later in life, these relationships have not yet been established for adults with MDD and current SES.“
How the Study Worked
In this study, researchers focused mainly on household income as a measure of socioeconomic status. The study included over 300 adults, both with and without major depressive disorder. Participants completed questionnaires to assess motivation and reward sensitivity, provided blood samples to measure inflammation, including interleukin 1 beta, a protein involved in the immune system, and underwent resting-state brain scans to examine connections between brain regions involved in reward and goal-directed behaviour.
Participants with major depressive disorder were treated with the antidepressant escitalopram, and their symptoms were monitored over time to track treatment response. The researchers then analyzed how socioeconomic status was associated with differences in reward processing, brain connectivity, inflammation, and the rate of symptom improvement.
What Did This Study Reveal?
The study identified several important connections between socioeconomic status and how depression affects the brain and response to treatment:
- Among people with major depressive disorder, those from lower income households reported lower motivation to pursue goals, a key part of reward processing.
- Lower income was associated with differences in resting state connections between the striatum and other brain regions involved in reward and decision making.
- Participants with lower income showed slower improvement during antidepressant treatment compared with those from higher income households.
- Levels of interleukin 1 beta, an immune related inflammatory protein, varied by income among people with major depressive disorder, although this relationship was partly influenced by body mass index.
Together, these findings add to growing evidence that socioeconomic conditions are linked not only to mental health outcomes, but also to differences in brain function and biological processes involved in depression and recovery.
Why This Matters
Depression is influenced by a combination of biological, psychological, and social factors, and this study suggests that socioeconomic conditions are an important part of that picture. Understanding how social and economic experiences become connected to brain and biological processes may help researchers and clinicians develop treatment approaches that take multiple aspects of a person’s life into account. In the long term, this could support more equitable and effective care for people from different socioeconomic backgrounds.
“…better characterizing how SES interacts with an individual’s well-being and their neurobiology, and by extension identifying how these factors can be directly targeted, is vital for ensuring the best possible outcomes for people affected by MDD”
Limitations to Consider
In this study, socioeconomic status was measured using household income and education, which provide useful insights but do not capture the full complexity of a person’s life circumstances. While the findings do not show direct cause and effect, they highlight how social and biological factors may interact to shape depression outcomes. Building on these results, future research can further explore these interactions to improve understanding and treatment of depression.
Final Takeaway
The findings from this study highlight that depression is shaped not only by biology but also by social and economic factors. By examining how socioeconomic conditions relate to brain function and treatment response, researchers can gain a fuller understanding of why people respond differently to antidepressants. With further research, integrating social and economic context into depression care could help clinicians develop more personalized and effective treatments, ultimately supporting better outcomes for people across diverse communities.
Citation: Jani, S., Hassel, S., Foster, J. A., Turecki, G., Bock, N., Churchill, N., Mueller, D. J., Lam, R. W., Taylor, V. H., Milev, R., Soares, C., Rotzinger, S., Rizvi, S. J., Kennedy, S. H., Frey, B. N., & Dunlop, K. (2026). Socioeconomic status is associated with reward processing, interleukin 1β, striatal connectivity, and antidepressant outcomes in individuals with major depressive disorder: A can-bind-1 report. Biological Psychiatry Global Open Science, 6(2), 100649. https://doi.org/10.1016/j.bpsgos.2025.100649