Teenagers Appear to be ‘Spreading’ Mental Illness

As if teenagers didn’t have it bad enough. New research now suggests that they might be “infecting” their classmates with mental disorders.

JAMA Psychiatry just published a paper that claims that ninth-grade students who have a friend struggling with a mental disorder were more likely to develop – or at least report – one themselves.

Startling Results

The nationwide cohort study, which mined multiple registry datasets, found that teenagers exposed to peers with mental disorders during the ninth grade were more likely to receive similar diagnoses as they grew older. This increased risk persisted even after the researchers adjusted for several parental, school-level, and area-level factors.

Other important results include:

• The “transmission” risk appeared to be noticeably higher – at least 5 percent – when multiple classmates had mental disorders.
• The risk jumped most visibly in the first year after exposure. By as much as 9% for those with one diagnosed classmate and by 18% for those with multiple classmates.
• The study singled out mood, anxiety, and eating disorders as the most strongly linked with this elevated risk.

The findings suggest that mental disorders might be socially transmitted within adolescent peer networks. As a result, the data suggests that caregivers should consider peer influences when looking at prevention and intervention strategies.

Methodology

The groundbreaking research project involved more than 700,000 Finnish citizens. The researchers looked at anyone born between 1985 and 1997. They pulled data from multiple national registers, following study participants from the time they finished the ninth grade until they received a mental disorder diagnosis, emigrated, died, or until the end of 2019.

Researchers defined “exposure” as having one or more classmates diagnosed with a mental disorder in the ninth grade. Additionally, the team measured mental disorder diagnoses during the follow-up period as the main outcomes.

Making Sense of the Results

“If mental disorders are transmitted socially via peer networks, the phenomenon could be explained by several mechanisms,” the researchers wrote. “One plausible mechanism is the normalization of mental disorders through increased awareness and receptivity to diagnosis and treatment when having individuals with diagnosis in the same peer network.”

At the same time, the authors pointed out that teenagers who lacked peers with a diagnosis might not seek help.

“For some diagnosis categories, such as eating disorders, transmission could also occur through processes of peer social influence to which adolescents are particularly susceptible,” they added. “Another possible mechanism facilitating the transmission of certain mental disorders, such as depression, pertains to direct interpersonal contagion. For instance, it is conceivable that long-term exposure to a depressive individual could lead to [the] gradual development of depressive symptoms through the well-established neural mechanisms of emotional contagion.

The researchers argued for the need for further research to explore how mental disorders travel within peer networks. Future research could also identify effective strategies for prevention and intervention in school settings. The findings pave the way for policies that could significantly reduce the societal and economic burden of mental disorders.

Further Reading

They’re Just Like Us: Celebrities Normalize Mental Health Breaks

Mental Health Diagnoses Take Unprecedented Leap

Suicide Plagues Student-Athletes