Abstract
Most mental disorders emerge in adolescence or young adulthood and are associated with a high burden and negative outcomes. The etiology of mental disorders is complex, starting with a diffuse pattern of subclinical symptoms in adolescence which precedes the onset of various full-blown disorders. Early detection of psychopathology in adolescence is important to prevent the progression of these problems. This thesis aimed to advance our understanding of adolescent psychopathology by identifying youth at risk for psychopathology, examining environmental risk factors, and evaluating access to mental health care.
To establish the iBerry Study, we screened over 16,000 adolescents at age 13 to select a cohort of adolescents at risk of developing psychopathology. Five years later we showed that these high-risk adolescents had a four to sevenfold risk of significant emotional and behavioral problems at age 18. Next, we studied the associations between several risk factors and psychopathology. First, we studied the effects of the COVID-19 pandemic on adolescent mental health. We showed that most adolescents reported emotional and behavioral symptoms within the normal range during the pandemic. For adolescents with severe problems before the pandemic, symptoms decreased during the pandemic. Second, we examined the effect of living in an urban area, where we found that, specifically for boys, living in an urban area or area with low greenspace density was associated with psychotic experiences. Third, we combined fourteen environmental risk factors into one composite score, the poly-environmental risk score (PERS). The PERS at age 15 was associated with psychotic experiences and symptoms at age 18. Fourth, we combined data from Dutch high-risk adolescents with data from Italian clinical adolescents to study if psychotic symptoms were associated with suicidality. We found that delusional ideas were associated with suicidal ideations and suicidal attempts.
Despite the prevalence of mental health problems, the majority of affected adolescents did not receive mental healthcare. Even among those with severe symptoms, access to care was limited. Especially boys were less likely to receive care. These studies showed the importance of recognizing problems early and the variety of factors that are associated with the onset of mental health problems. Finally, suggestions for future directions, both for research and prevention are described.
To establish the iBerry Study, we screened over 16,000 adolescents at age 13 to select a cohort of adolescents at risk of developing psychopathology. Five years later we showed that these high-risk adolescents had a four to sevenfold risk of significant emotional and behavioral problems at age 18. Next, we studied the associations between several risk factors and psychopathology. First, we studied the effects of the COVID-19 pandemic on adolescent mental health. We showed that most adolescents reported emotional and behavioral symptoms within the normal range during the pandemic. For adolescents with severe problems before the pandemic, symptoms decreased during the pandemic. Second, we examined the effect of living in an urban area, where we found that, specifically for boys, living in an urban area or area with low greenspace density was associated with psychotic experiences. Third, we combined fourteen environmental risk factors into one composite score, the poly-environmental risk score (PERS). The PERS at age 15 was associated with psychotic experiences and symptoms at age 18. Fourth, we combined data from Dutch high-risk adolescents with data from Italian clinical adolescents to study if psychotic symptoms were associated with suicidality. We found that delusional ideas were associated with suicidal ideations and suicidal attempts.
Despite the prevalence of mental health problems, the majority of affected adolescents did not receive mental healthcare. Even among those with severe symptoms, access to care was limited. Especially boys were less likely to receive care. These studies showed the importance of recognizing problems early and the variety of factors that are associated with the onset of mental health problems. Finally, suggestions for future directions, both for research and prevention are described.
| Original language | English |
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| Award date | 16 Sept 2025 |
| Place of Publication | Rotterdam |
| Publication status | Published - 16 Sept 2025 |
