Significant scientific progress has been made in the field of infant and preschool psychiatry over the past 2 decades. Although this is a field with a long and rich theoretical history, empirical investigations of psychiatric disorders in infants and preschoolers have significantly lagged behind other areas of psychiatry and medicine. Advances in the understanding of early normative social and emotional development over the past decade as well as the more recent availability of age-appropriate psychiatric interviews for the caregivers of young children have facilitated investigations of very early–onset mental disorders.
Following these advances, empirical validation for several Axis I psychiatric disorders in children as young as 2 or 3 years has become available. These disorders include major depressive disorder (MDD), posttraumatic stress disorder (PTSD), oppositional defiant disorder (ODD), and attention-deficit/hyperactivity disorder (ADHD). Autism has been well described in young children for many decades, with more recent focus on even earlier detection in infancy. Investigations of the nosology of anxiety disorders and attachment disorders are under way. These advances are of obvious importance for ameliorating the impairments and relieving the suffering of young children.
Beyond their importance to the field of child psychiatry, these advances may also have implications for intervention in mental disorders across the life span. This is based on the exciting possibility that earlier intervention during a period of rapid developmental change and brain neuroplasticity early in life may provide a window of opportunity for greater treatment effects. The robust efficacy of early intervention—while broadly accepted as key for many years in numerous general developmental domains, such as speech, language, and motor development—is also emerging in several specific mental disorders. The importance of identifying mental disorders at the earliest possible developmental point during infancy and the preschool period is underscored by relatively enhanced treatment effects found in autistic spectrum and disruptive disorders.1-3
The social and emotional sentience of young children
There has been a widespread and long-standing assumption that young children are not vulnerable to serious mental disorders. Related to this is the presumption that young children are emotionally unaware and unsophisticated and therefore are unreactive or relatively immune to emotional experiential events. The latter presumption has been refuted by empirical literature on the social and emotional development of young children.4,5
As the early emotional competency of young children was elucidated—including their sensitivity to trauma, their very early ability to distinguish their caregivers from others, and their ability to experience complex emotions such as guilt and shame—so was detection and understanding of early-onset mental disorders. These findings highlight the vulnerability of young children to traumatic life events and negative emotional experiences and underscore the need for attention to these early developmental domains. A vast and diverse literature stresses the central importance of developing and maintaining nurturing psychosocial environments for young children.
The need for age-appropriate assessment techniques
Numerous Axis I mental disorders, including MDD, PTSD, anxiety disorders, ADHD, ODD, attachment disorders, and autistic spectrum disorders are now known to arise in very early childhood.6,7 However, the detection and accurate diagnosis of these conditions in very young children can be complicated and challenging for the clinician. Psychiatric assessment of the infant and preschooler requires specialized techniques, observations over time whenever possible, and the need to distinguish clinically significant symptoms from the normative behavioral and emotional extremes known to characterize early childhood.
Key features of the diagnostic assessment of the young child are the centrality of the child-caregiver relationship, or “dyad,” as the unit of observation. This is based on the well-established principle that the young child is inextricably dependent on the caregiver for emotional functioning and well-being. In addition, the context and relationship specificity of symptom expression and the use of play as the medium of observation are also key guiding principles of the infant and preschool mental health evaluation. The evaluation of the young child should always be done in the context of play within the child-caregiver dyad. Given the need for this, assessments are generally performed over several weeks.
Multiple observations are needed because of the potentially powerful impact of fatigue or even mild illness on the behavior of a young child, which often gives rise to a nonrepresentative mental status examination. Play observations with different caregivers are also key to gaining a clear clinical picture. Semistructured interview formats that allow the clinician to observe the dyad under a variety of evocative circumstances, such as eating, structured play, free play, and brief separations and reunions, are often useful. Along this line, clinicians and parents should be wary of psychiatric diagnoses given to young children after only 1 brief observation of behavior. Articles outlining practice parameters and chapters describing these age-adjusted techniques in more detail are available.8,9
? Empirical validation for several Axis I psychiatric disorders in children as young as 2 or 3 years has become available. Basic developmental findings indicate that young children are vulnerable to traumatic life events and negative emotional experiences.
? Key features of the diagnostic assessment of young children are the centrality of the child-caregiver relationship, or “dyad,” as the unit of observation. Multiple observations are needed because of the potentially powerful impact of fatigue or even mild illness on the behavior of a young child, which often gives rise to a nonrepresentative mental status examination.
? One of the central issues in conducting an age-appropriate clinical or research assessment of the young child is the need to probe for developmentally adjusted symptom manifestations.
Developmental adjustments to symptom manifestations
One of the central issues in conducting an age-appropriate clinical or research assessment of the young child is the need to probe for developmentally adjusted symptom manifestations. Simply on the basis of life experiences of the young child compared with those of the older child or adult, some symptoms will be manifest and evidenced differently. One obvious example is decreased libido; this common manifestation of anhedonia in an adult is not a developmentally possible manifestation of anhedonia in a young child.
However, age-adjusted manifestations of anhedonia, not a normative variation in a young child, includes the inability to enjoy play, which is commonly seen in depressed young children. Thus, anhedonia can occur throughout the age span, but its manifestations will be evident in a developmentally specific fashion.
If clinicians probe for key symptoms of DSM disorders typically designed for adults and older children, they are likely to conclude that symptoms are not present and therefore may fail to detect a disorder. Several age-adjusted structured and semistructured interviews for research use have been developed for the caregivers of young children. Although they are not designed for clinical use, such tools may help guide clinical interviews.10,11
Clinical presentation of Axis I disorders in preschoolers
While a surprising level of continuity has been evident in the core symptoms of several Axis I psychiatric disorders in children as young as preschool age, the need for some important developmental adjustments has also become clear. Two disorders well known in adults but also seen in preschoolers, for which there is a relatively large database, might serve as illustrative contrasting examples of continuities and discontinuities in nosology across this age span.
MDD has been identified in preschoolers and shows continuity in the same core criteria when developmental adjustments of symptom manifestations are assessed. The question of whether the 2-week duration criterion should be modified for the preschooler has been raised; empirical data suggest that the same duration threshold may not apply at this younger age. Barring that adjustment, however, no modifications of the basic nosology appear to be indicated, which suggests that the nosology of MDD shows continuity across the age span.
In contrast, PTSD has also been detected and validated in children as young as 3 years. However, to cross the clinical threshold, the empirical data suggest that fewer avoidance and numbing (criterion C) symptoms be required.12
Adjustments are also needed regarding the manner in which multiple symptoms may manifest (a developmental adjustment as above). Therefore, PTSD is a disorder in which developmental adjustments to the basic nosology appear to be indicated. Empirical studies of several other Axis I disorders in preschoolers have been done or are ongoing and will clarify the continuity and discontinuity of nosology across the age span.
Prevalence rates and referral patterns
As is well established in older children with mental health disorders, young children with disruptive behavior are more frequently referred for evaluation and treatment than those with primary symptoms of mood or anxiety disorders. Autistic spectrum disorders are increasingly being detected earlier, and young children often present to infant and preschool mental health settings with symptoms of these disorders.
It is less common for children with mood or anxiety disorders to be referred unless symptoms become severe or unless families are particularly familiar with or sensitive to these symptoms. More subtle manifestations that do not produce obvious impairment in the home or school setting are likely to go undetected. To date, large-scale epidemiological studies of mental disorders in young children that use updated DSM criteria and assessment techniques have not been conducted and are needed. However, smaller epidemiological studies have demonstrated that the prevalence of Axis I major mental disorders is similar to that in older children, when age-adjusted criteria were used when indicated.13,14
Treatment of early-onset mental disorders
Because the recognition of early-onset mental disorders has only recently become more widely accepted, the testing and development of age-specific treatments has also been slow to emerge. Some empirically supported early interventions are available, such as Parent-Child Interaction Therapy (PCIT) and the Incredible Years, for disruptive behavioral disorders, and Applied Behavior Analysis and its variants, for autistic spectrum disorders. Other psychotherapeutic treatments, in particular, various forms of play therapy, have been widely used clinically but have not for the most part been sufficiently tested in empirical studies. Early dyadic psychotherapeutic interventions for MDD (an adapted version of PCIT) and PTSD (an adaptation of cognitive-behavioral therapy) are undergoing testing, and preliminary findings appear to be promising.12,15
Despite increasing rates of pharmacological treatment being prescribed for preschool-age children, in general, psychopharmacology should be avoided in this age-group. The exceptions to this are for use to target dangerous self-destructive or aggressive symptoms in autism and the cautious use of stimulants for ADHD in preschoolers; both indications are supported by double-blind placebo-controlled studies. With these exceptions, psychopharmacological options are insufficiently tested and not indicated as first- or second-line treatment of psychiatric disorders in preschoolers.
The gap between scientific data, clinical practice, and public policy
Advances in our understanding of early emotional development and early-onset mental disorders have yet to be incorporated into clinical practice and public policy. Despite a significant body of emerging data that demonstrate that children as young as 2 or 3 years can manifest Axis I psychiatric disorders, it is still uncommon for such young children to be referred for mental health services. Unfortunately, primary care physicians still commonly assume that these children are too young to be vulnerable to mental disorders. At the same time, psychotropic medications are being prescribed for very young children at an exponentially increasing rate for unclear indications and presumably without age-appropriate mental health evaluations.16
A likely contributor to this trend is the lack of mental health clinicians with expertise in the assessment and treatment of young children. There is also a lack of access to age-appropriate psychotherapies, which are not widely available despite several psychotherapeutic and developmental treatments with very solid empirical data to support their efficacy.1,3 In this context, primary care physicians may be inclined to prescribe psychotropic medications to provide more immediate, and unfortunately more feasible, assistance to distressed families.
Problems with access to treatment notwithstanding, significant efforts must now be made to educate general psychiatrists and primary care physicians about advances in infant and preschool mental health. This should include knowledge of how to screen for and refer children with early-onset symptoms as well as of the availability of age-appropriate psychotherapeutic treatments. Expansion of age-appropriate developmental psycho-therapeutic services must become a top public health priority to make these treatments more widely available to young children and to capture the potential greater benefit of the earliest possible intervention for mental disorders.
1. Brinkmeyer M, Eyberg SM. Parent-child interaction therapy for oppositional children. In: Kazdin AE, Weisz JR, eds. Evidence-Based Psychotherapies for Children and Adolescents. New York: Guilford Press; 2003:204-223.
2. Dawson G. Early behavioral intervention, brain plasticity, and the prevention of autism spectrum disorder. Dev Psychopathol. 2008;20:775-803.
3. Rogers SJ, Vismara LA. Evidence-based comprehensive treatments for early autism. J Clin Child Adolesc Psychol. 2008;37:8-38.
4. Saarni C. Emotional competence: a developmental perspective. In: Bar-On R, Parker JDA, eds. The Handbook of Emotional Intelligence. San Francisco: Jossey-Bass; 2000:68-91.
5. Denham SA. Emotional Development in Young Children. New York: Guilford Press; 1998.
6. Luby JL, Belden A. Mood disorders. In: Luby JL, ed. Handbook of Preschool Mental Health: Development, Disorders and Treatment. New York: Guilford Press; 2006.
7. Luby JL. Depression. In: Zeanah CH Jr, ed. Handbook of Infant Mental Health. 2nd ed. New York: Guilford Press; 2000:382-396.
8. Luby JL, Tandon M. Assessing the preschool-age child (4-5). In: Dulcan MK, ed. Dulcan’s Textbook of Child and Adolescent Psychiatry. Washington, DC: American Psychiatric Publishing; 2009:15-25.
9. Thomas JM, Benham AL, Gean M, et al. Practice parameters for the psychiatric assessment of infants and toddlers (0-36 months). American Academy of Child and Adolescent Psychiatry. J Am Acad Child Adolesc Psychiatry. 1997;36(10 suppl):21S-36S.
10. Egger HL, Ascher B, Angold A. The Preschool Age Psychiatric Assessment: Version 1.4. Durham, NC: Center for Developmental Epidemiology, Department of Psychiatry and Behavioral Sciences, Duke University Medical Center; 2003.
11. Fisher P, Lucas C. Diagnostic Interview Schedule for Children (DISC-IV): Young Child. New York; Columbia University; 2006.
12. Scheeringa MS, Weems CF, Cohen JA, et al. Trauma-focused cognitive-behavioral therapy for posttraumatic stress disorder in three through six year-old children: a randomized clinical trial. J Child Psychol Psychiatry. In press.
13. Egger HL, Angold A. Common emotional and behavioral disorders in preschool children: presentation, nosology, and epidemiology. J Child Psychol Psychiatry. 2006;47:313-337.
14. Lavigne JV, Lebailly SA, Hopkins J, et al. The prevalence of ADHD, ODD, depression, and anxiety in a community sample of 4-year-olds. J Clin Child Adolesc Psychol. 2009;38:315-328.
15. Lenz SN, Pautsch J, Luby JL. Parent-child interaction therapy emotion development: a novel treatment for depression in preschool children. Depression Anxiety. In press.
16. Olfson M, Crystal S, Huang C, Gerhard T. Trends in antipsychotic drug use by very young, privately insured children. J Am Acad Child Adolesc Psychiatry. 2010;49:13-23.