• Science Update
About 20 percent of U.S. youth during their lifetime are affected by some type of mental disorder to an extent that they have difficulty functioning, according to a new NIMH survey published in the October 2010 issue of the Journal of the American Academy of Child and Adolescent Psychiatry. The data support the observation from surveys of adults that mental disorders most commonly start in early life.
Many regional surveys conducted in the United States have indicated that about one in four to five children experience a mental disorder sometime in their life. But until now, no nationally representative surveys had been conducted to determine if these prevalence rates of a wide range of mental health problems hold true across the nation.
Kathleen Merikangas, Ph.D., of NIMH and colleagues analyzed data from the National Comorbidity Study-Adolescent Supplement (NCS-A), a nationally representative, face-to-face survey of more than 10,000 teens ages 13 to 18. They used standard diagnostic criteria set by the American Psychiatric Association's Diagnostic and Statistical Manual (DSM-IV) to determine lifetime prevalence of mental disorders among the teens. To follow up on the teens' responses, they also collected data via mailed questionnaires completed by one parent or guardian of each teen surveyed.
Results of the Study
Overall, nearly half of the sample reported having met diagnostic criteria for at least one disorder over a lifetime, and about 20 percent reported that they suffered from a mental disorder with symptoms severe enough to impair their daily lives. In addition,
- 11 percent reported being severely impaired by a mood disorder (e.g., depression or bipolar disorder),
- 10 percent reported being severely impaired by a behavior disorder such as attention deficit hyperactivity disorder or conduct disorder,
- 8 percent reported being severely impaired by at least one type of anxiety disorder.
In addition, about 40 percent of those who reported having a disorder also met criteria for having at least one additional disorder. Those with a mood disorder were more likely than others to report having a coexisting disorder. Underscoring the notion that mental disorders manifest early in life, the researchers also found that symptoms of anxiety disorders tended to emerge by age 6, behavior disorders by age 11, mood disorders by age 13, and substance use disorders by age 15.
The researchers also noted strong links between parental characteristics and their teen's disorders. For example, children of parents with less education (e.g., no college degree) were at an increased risk for having any kind of mental disorder. And compared to teens with married or cohabiting parents, those with divorced parents also were at higher risk for a disorder, especially anxiety, behavior and substance use disorders.
The NSC-A results provide a broader and longer-term outlook compared with last year's National Health and Nutrition Examination Survey (NHANES), which asked respondents about diagnosed disorders and service use within a 12-month window only, and was limited to six disorders.
According to the NCS-A researchers, the percentage of youth suffering from mental disorders is even higher than the most frequent major physical conditions in adolescence, including asthma or diabetes. The results reiterate the importance of developing prevention strategies and promoting early intervention for at-risk children and adolescents.
More research is needed to better understand the risk factors for developing a mental disorder in youth, as well as how to predict which disorders may continue into adulthood. In addition, the researchers acknowledge the need for more prospective research to tease apart the complex interplay among socioeconomic, biological and genetic factors that may contribute to the development of mental disorders in youth.
Merikangas KR, He J, Burstein M, Swanson SA, Avenevoli S, Cui L, Benjet C, Georgiades K, Swendsen J. Lifetime prevalence of mental disorders in U.S. adolescents: Results from the National Comorbidity Study-Adolescent Supplement (NCS-A). Journal of the American Academy of Child and Adolescent Psychiatry. 2010 Oct. 49(10):980-989.