Largest study on mental health contagion among schoolmates reveals significant risks of mood, anxiety, and eating disorders

Researchers discovered that mental disorders spread within school social networks, revealing a critical public health issue. Analyzing data from over 700,000 Finnish ninth-graders, they found that having classmates with mental disorders significantly increased the likelihood of being diagnosed with similar conditions later in life. This contagion effect, strongest within the first year, was most notable for mood, anxiety, and eating disorders. These findings underscore the need for preventive measures and early interventions in schools to address mental health issues proactively.

The study, conducted by the University of Helsinki, the Finnish Institute for Health and Welfare, the University of Jyväskylä, and the University of Manchester, is the largest and most comprehensive investigation into the spread of mental disorders within social networks. It involved more than 700,000 ninth-grade pupils from 860 Finnish schools, followed for a median of 11 years.

Researchers demonstrated a clear association between the number of classmates diagnosed with a mental disorder and an increased risk of future mental disorder diagnoses. “The observed link was the strongest during the first year of follow-up,” said Associate Professor Christian Hakulinen of the University of Helsinki. “This link was not explained by factors related to parents, school, and residential area and was most pronounced for mood, anxiety, and eating disorders.”

Hakulinen highlighted that previous studies yielded similar results, with American researchers noting depressive symptoms potentially transmitted within social networks. However, these studies often involved social networks chosen by the subjects, potentially biasing the data. School classes provide a more unbiased social network, as students typically do not choose their classmates.

“Defining social networks and following adolescents was made possible by comprehensive Finnish registers,” Hakulinen explained. “The findings deepen our understanding of how mental health problems develop and spread within social networks.”

Hakulinen emphasized that the connection observed in the study is not necessarily causal. The study did not explore the mechanisms of mental disorder transmission between individuals. He suggested that the normalization of seeking help for mental health issues might contribute to this contagion effect. “The threshold for seeking help might be lowered when others in the network have already sought help, which can be considered a beneficial contagion,” he added.

The study highlights the pressing need for preventive measures and early intervention. Mental disorders present a significant global challenge, impacting individuals, society, and the economy. Hakulinen stressed the increasing prevalence of anxiety and mood symptoms among young people and the importance of addressing these issues early.

“Considering preventive measures, it is crucial to recognize that mental disorders can spread from one adolescent to another,” Hakulinen emphasized. The study followed 713,809 Finnish citizens born between 1985 and 1997, from the end of comprehensive school until they received their first mental disorder diagnosis, moved abroad, or died, with follow-up ending in 2019. The median follow-up period was 11.4 years.

Funding for the study came from the European Research Council (ERC) and the Research Council of Finland.

Analysis:

The study on the spread of mental health disorders within school social networks presents significant implications from various perspectives. This analysis will explore the findings’ ramifications from sociological, psychological, and public health viewpoints.

Sociologically, the study underscores the importance of social networks in shaping individual health outcomes. The contagion effect of mental disorders highlights the role of peer influence in adolescent development. School environments, where adolescents spend significant time and form crucial social bonds, become critical in understanding and addressing mental health issues. This finding suggests that interventions should not only target individuals but also consider the broader social context, including peer relationships and school dynamics.

Psychologically, the study’s findings align with existing theories on social learning and emotional contagion. Adolescents may mimic behaviours and emotional responses observed in their peers, leading to the spread of mental health issues. This phenomenon underscores the need for mental health education and support within schools, promoting healthy coping mechanisms and resilience. It also suggests that early intervention programs should involve peer support systems to mitigate the negative impact of mental health contagion.

From a public health perspective, the study highlights the urgent need for comprehensive mental health strategies in educational settings. Preventive measures should focus on early detection and intervention, with schools serving as critical sites for mental health promotion. Policies should ensure access to mental health resources, training for educators, and programs that foster a supportive and inclusive school environment. This approach can help address the rising prevalence of mental disorders among adolescents and reduce the long-term societal and economic burden of untreated mental health issues.

Economically, the findings suggest that investing in school-based mental health programs can yield significant returns. Early intervention can prevent the escalation of mental health issues, reducing healthcare costs and improving productivity and academic performance. Policymakers should consider these economic benefits when allocating resources to mental health initiatives in schools.

In conclusion, the study on mental health disorders spread within school social networks reveals critical insights into the role of peer influence in adolescent mental health. Addressing this issue requires a multifaceted approach, involving sociological, psychological, and public health strategies. By implementing comprehensive preventive measures and early interventions, we can mitigate the spread of mental health issues and promote healthier outcomes for adolescents.