Although it is sometimes assumed that childhood and adolescence are times of carefree bliss, as many as 20% of children and adolescents have a diagnosable mental disorder that causes impairment (1). With increasing age, more children develop one or more disorders. All told, about 27.9% of US adolescents aged 13 to 17 are reported to meet criteria for 2 or more disorders (2). Recent studies that follow children from birth to adulthood indicate that most adult mental health disorders begin in early childhood and adolescence (3, 4). Genes associated with mental health disorders have been reported to show high expression throughout the lifespan, beginning in the 2nd trimester and impacting neurodevelopmental processes, which may explain the early ages of onset (5). Most of these disorders may be viewed as exaggerations or distortions of normal behaviors and emotions.
Like adults, children and adolescents vary in temperament. Some are shy and reticent; others are socially exuberant. Some are methodical and cautious; others are impulsive and careless. Whether a child is behaving like a typical child or has a disorder is determined by the presence of impairment and the degree of distress related to the symptoms. For example, a 12-year-old girl may be frightened by the prospect of delivering a book report in front of her class. This fear would be viewed as social anxiety disorder only if her fears were severe enough to cause significant distress and avoidance.
There is much overlap between the symptoms of many disorders and the challenging behaviors and emotions of normal children. Thus, many strategies useful for managing behavioral problems in children can also be used in children who have mental disorders. Furthermore, appropriate management of childhood behavioral problems may decrease the risk of temperamentally vulnerable children developing a full-blown disorder. Also, effective treatment of some disorders (eg, anxiety) during childhood may decrease the risk of mood disorders later in life.
The most common mental disorders of childhood and adolescence fall into the following categories:
Schizophrenia and related psychotic disorders are much less common.
Pediatric catatonia is more common than childhood schizophrenia. It may represent a psychiatric disorder but often occurs in medical conditions (eg, infections, metabolic disorders, autoimmune conditions) and is not detected by pediatricians (6).
However, more often than not, children and adolescents have symptoms and problems that cut across diagnostic boundaries. For example, > 25% of children with ADHD also have an anxiety disorder, and 25% meet the criteria for a mood disorder.
1. Merikangas KR, He JP, Burstein M, et al: Lifetime prevalence of mental disorders in US adolescents: Results from the National Comorbidity Study – Adolescent Supplement (NCS-A). J Am Acad Child Adolesc Psychiatry 49(10):980-989, 2010.
2. Kessler RC, Avenevoli S, McLaughlin KA, et al: Lifetime comorbidity of DSM-IV disorders in the National Comorbidity Survey – Replication Adolescent Supplement (NCS-A). Psychol Med 42(9)1997-2010, 2012.
3. Dalsgaard S, Thorsteinsson E, Trabjerg BB, et al: Incidence rates and cumulative incidences of the full spectrum of diagnosed mental disorders in childhood and adolescence. JAMA Psychiatry, 77(2):155-164, 2020. doi: 10.1001/jamapsychiatry.2019.3523
4. Caspi A, Houts RM, Ambler A, et al: Longitudinal assessment of mental health disorders and comorbidities across 4 decades among participants in the Dunedin birth cohort study. JAMA Netw Open 3(4):e2032210, 2020.
5. Lee PH, Anttila V, Won H, et al: Genome-wide meta-analysis identifies genomic relationships, novel loci, and pleiotropic mechanisms across eight psychiatric disorders. Cell2019. doi.org/10.1101/528117
6. Dhossche DM, Wachtel LE: Catatonia is hidden in plain sight among different pediatric disorders: A review article. Pediatr Neurol 43(5):307-315, 2010. doi: 10.1016/j.pediatrneurol.2010.07.001
Evaluation of mental complaints or symptoms in children and adolescents differs from that in adults in important ways:
Developmental context is critically important in children. Behaviors that are normal at a young age may indicate a serious mental disorder if present at an older age.
Children exist in the context of a family system, and that system has a profound effect on children’s symptoms and behaviors; normal children living in a family troubled by domestic violence and substance abuse may superficially appear to have one or more mental disorders.
Children also exist in the context of environmental stressors such as the COVID-19 pandemic and military conflict. The resultant disruption of critical routines and isolation from extended family, peers, teachers, and cultural and religious groups have a significant impact, especially on the most vulnerable groups (1).
Children often do not have the cognitive and linguistic sophistication needed to accurately describe their symptoms. Thus, the clinician must rely very heavily on direct observation corroborated by observations of other people, such as parents and teachers.
In many cases, developmental and behavioral problems (eg, poor academic progress, delays in language acquisition, deficits in social skills) are difficult to distinguish from those due to a mental disorder. In such cases, formal developmental and neuropsychologic testing should be part of the evaluation process.
Because of these factors, evaluation of children with a mental disorder is typically more complex than that of adults. However, most cases are not severe and can be competently managed by an appropriately trained primary care practitioner. However, uncertain or severe cases are best managed in consultation with a child and adolescent psychiatrist.