Background: We have few data on incidence of psychiatric disorders among adolescents. This study examined first incidence of disorders among adolescents and baseline factors which increased or decreased risk of new onset cases a year later.
Methods: Data were analyzed from Teen Health 2000 (TH2K), a probability sample of 4,175 youths 11-17 and their parents assessed at baseline and 3,134 of these youth-parent dyads followed up a year later. Disorders examined were anxiety, mood, attention deficit hyperactivity disorder (ADHD), disruptive, and substance abuse/dependence disorders in the past year. Risk and protective factors were assessed from three domains: status factors, personal and social resources, and stressors. Logistic regression models were used to estimate odds of incident disorders for each risk and protective factor.
Results: Incidence rates were 2.8% for anxiety, 1.5% for mood, 1.2% for ADHD, 2.5% for disruptive, 2.9% for substance abuse/dependence, and 7.5% for one or more DSM-IV disorders. Multivariate analyses identified few independent predictors of incidence. The most consistent factors across disorders involved indicators of stress. The role of adverse family context was particularly noteworthy, predicting incidence of every disorder examined. Personal resources such as mastery consistently enhanced resilience to onset of first episodes. The presence of multiple risk factors, cumulative burden, substantially increased risk of first incidence of all disorders examined.
Conclusions: The incidence of any disorder of 7.5% was similar to two earlier studies using DSM-III-R criteria (8.9 and 10.6, respectively). This is the first study to estimate incidence of DSM-IV disorders for a range of diagnostic categories, and with the exception of substance use disorders, the rates are quite different from one earlier study using DSM-II-R criteria. A clear pattern emerged from the analyses. That is, psychiatric disorders, like other chronic diseases, are the product of multiple factors and these factors in turn have effects on multiple disorders.