Sad teenage girl

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HELSINKI — It’s not uncommon to see teens adopt similar mannerisms, lingo, and attitudes as their peers. According to new research out of Finland, however, it turns out mental health disorders may be just as contagious across cliques. The study uncovers a potential connection between adolescent social networks and the development of psychological issues later in life.

The findings, published in JAMA Psychiatry, suggest that having classmates diagnosed with mental health issues during the formative high school years may increase an individual’s risk of facing similar challenges down the road.

Drawing from an extensive dataset of over 700,000 individuals, researchers from the University of Helsinki and collaborating institutions across Europe tracked the mental health trajectories of Finnish citizens born between 1985 and 1997. By cross-referencing comprehensive school records with nationwide health registries, the study aimed to shed light on the connection between peer relationships and psychological well-being.

The results were intriguing: Individuals who had one or more ninth-grade classmates diagnosed with a mental disorder showed a slightly elevated risk of receiving a mental health diagnosis themselves in the years following graduation. This association held true even after accounting for a wide range of factors, such as parental mental health history, socioeconomic status, and school characteristics.

Interestingly, the study found that the risk was most pronounced in the first year after exposure to a diagnosed classmate, with a 9% increase for those with one such peer and an 18% increase for those with multiple affected classmates. The association was particularly strong for mood disorders, anxiety disorders, and eating disorders.

How are mental health disorders transmitted between teens?

While the exact mechanisms behind this potential “transmission” of mental health issues remain unclear, the researchers propose several plausible explanations. One possibility is that having peers with diagnosed disorders may normalize seeking help and receiving treatment, leading to increased recognition of one’s own mental health challenges. Alternatively, direct social influence and emotional contagion could play a role, with prolonged exposure to a struggling friend potentially contributing to the development of similar symptoms.

However, it’s crucial to note that the observed associations, while statistically significant, were relatively small in magnitude. The study’s authors caution against jumping to definitive conclusions, emphasizing the need for further research to disentangle the complex web of factors that shape mental health outcomes.

The study’s implications extend beyond the realm of public health, shedding light on the intricate dynamics of teenage friendships and their lasting impact on individual well-being. “The findings significantly deepen our understanding of how mental health problems develop and affect other people in our social networks,” says study co-author Christian Hakulinen, an associate professor at the University of Helsinki, in a statement.

Navigating friendships and cliques can be tricky for kids who want to fit in and maintain strong self-esteem. Parents should be on the lookout for symptoms of mental health struggles not only in their own children, but in those who they spend the most time with. Raising concerns with a sensitive teen can be difficult and delicate. If you’re unsure of how to approach the topic, speaking to a mental health professional first is always a good idea.

StudyFinds Editor-In-Chief Steve Fink contributed to this report.

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