It seems that every week there are fresh headlines about a mental health crisis in children and adolescents, reporting exploding rates of severe anxiety and depression in youth. These reports raise the question of whether or not there has been a significant change in their incidence: Are more children developing depressive and anxiety disorders? Are they having greater difficulty accessing care? Are the disorders more severe than they were in the past? Or are young people failing to develop appropriate skills to manage anxiety, sadness, and other forms of distress that are a normal (if unpleasant) part of life? These are important questions, as they will help us to advocate for the proper services to address the public health challenge that underlies this “epidemic.”
What do the data show?
It is important to start by noting that epidemiologic data on child psychiatry in the United States are not as robust as we might like. It was only in 1999 that the Surgeon General’s Report on Mental Health articulated that there was a need for a more systematic approach to collecting epidemiologic data on psychiatric illness in children and adolescents. At that time, the consensus was that approximately one in five children would develop a psychiatric illness by the age of 18 and that approximately 5% of all children would experience a severe or persistent mental illness.1 In the 2 decades since then there have been expanded efforts to collect data, including the addition of an adolescent supplement to the National Comorbidity Survey sponsored by the National Institute of Mental Health, although our current estimates still are based on representative surveys of thousands of U.S. children and teenagers, often with questionnaires filled out by their parents. Thus, we may have overestimates of some behavioral disorders that are obvious and of concern to parents or underestimates of certain internalizing disorders such as depression that can remain unstated and contained in the mind of the adolescent. And even with accurate current estimates, our ability to make statements about trends or changes in rates of disease is limited by the very short period of time in which we have been studying these disease rates in U.S. youth, some changes in definitions, and the unknown impact of increasing recognition rather than true change in incidence.
What is unequivocally clear is that psychiatric illnesses usually present in youth and that these illnesses are among the most common illnesses of youth. Current estimates are that nearly one in four young people will have a psychiatric illness (by The Diagnostic and Statistical Manual of Mental Disorders [DSM], Fifth Edition criteria) by the time they turn 18,2 although only 10% of youth will experience an illness that meets the Substance Abuse and Mental Health Services Administration criteria for a serious emotional disturbance, or one that has a substantial impact on a child’s ability to function socially, emotionally, and academically.3
While it once was believed that children did not experience psychiatric illness, we now know that the majority of psychiatric illnesses present during childhood, adolescence, and young adulthood. The Centers for Disease Control and Prevention estimates that 50% of lifetime psychiatric illness has presented by the age of 15 years and 75% by the age of 24. Only one-quarter of all lifetime psychiatric illnesses emerge in full adulthood, or after the age of 24. Early diagnosis and treatment can make a significant difference in the overall impact of serious illnesses such as schizophrenia and bipolar disorder. We also can state with confidence that anxiety disorders are the most common psychiatric illnesses of youth, making up over 30% of all diagnoses, followed by disorders of behavior (19%), mood (14%), and then substance use (11%).4 Even compared with asthma (with a prevalence of approximately 11%), widely considered to be among the most common disease of childhood, psychiatric illnesses are the most common in youth.
The question then is whether these numbers are changing. The National Comorbidity Survey conducted in 2014 found that the incidence of major depressive episodes in adolescents had increased significantly between 2005 and 2014, from 9% to 11%.5 This is a survey of nearly 200,000 youth across the United States, interviewed by phone with a structured questionnaire assessing their (self-reported) DSM criteria for a major depressive episode, along with other illnesses. During this time frame, access to specialty mental health providers increased among adolescents, alongside their rate of use of psychiatric medications and inpatient hospitalization.
In Europe, where they have more robust epidemiological data, there also has been a public perception of an increase in depression in adolescents. Studies there have suggested that prevalence rates have not changed significantly, and that the problem actually may be a function of a growing population, greater public awareness, and higher rates of psychological distress.6
In the United States, it is difficult to place the prevalence rates in a meaningful context, given the shorter time frame during which we have been following these rates in young people. It is worth highlighting that although the rates at which young people are gaining access to mental health clinicians, being prescribed medications, and being admitted to psychiatric hospitals all have increased, there has not been an associated decrease in the rate of illness or in the severity of symptoms. It certainly is possible that the increase in use of services by youth is being driven by the increased prevalence of this diagnosis, or it may be that other factors, such as those detailed in international studies, are driving this increase in the incidence of depression.