Bridging between youth psychiatry and child and adolescent psychiatry
Authors: Andrea Danese
Journal: World Psychiatry (2022)

Most adults who develop a psychiatric disorder already met criteria for a diagnosis in childhood or adolescent years1. In addition, an early onset of psychiatric disorders is associated with greater chronicity and complexity of later psychopathology1. These epidemiological findings are transforming the way we study and tackle psychiatric disorders. Research and clinical practice are increasingly moving away from models prioritizing fully established, late-stage disorders to instead address their risk factors and early manifestations. Investment in prevention and early intervention for psychiatric disorders in childhood and adolescent years may achieve the greatest returns by reducing distress and impairment at key developmental stages, promoting well-being and productivity over the life course – similarly to what has been proposed for education2. This cultural shift has promoted renewed interest in child and adolescent psychiatry and in youth psychiatry (aka early intervention psychiatry). The disciplines of child and adolescent psychiatry and youth psychiatry have emerged from different traditions, which are in many ways complementary and could be helpfully integrated. In particular, youth psychiatry originated from work in psychosis. Inspired by the neurodevelopmental model of psychosis, youth psychiatry has challenged the traditional system of care, focused on adult patients with chronic conditions. Instead, it has championed a novel system, focused on preventing or mitigating the onset of psychosis in adolescents and young adults through early intervention. Building on the success of the early intervention psychosis services, youth psychiatry now seeks to apply this model to address common mental disorders, including anxiety and depression3. The current attempts to apply the early intervention psychosis model to common mental disorders highlight both opportunities and challenges in supporting young people's mental health. A central feature of youth psychiatry is the focus on "the transitional developmental stage from puberty to independent adulthood, which extends approximately from 12 to 25 years"3. This focus is justified by the early onset of psychopathology. It is also justified by the need to smooth the often-problematic transition of affected young people from child and adolescent mental health services (CAMHS) to adult services, typically set at 18 years. This age cut-off for service provision is in part related to differences in existing legal frameworks, commissioning arrangements, and educational pathways for the work with young people aged below or above 18 years. However, the cut-off produces a major bottleneck for service delivery, right at the time when young people face key personal transitions into higher education and/or employment. Some young people disengage from adult services because these are not developmentally appropriate. Other young people are not accepted by adult services because these prioritize patients who have already accumulated significant impairment. The relaxation of the upper age cut-off championed by youth psychiatry offers a potential solution. In fact, many CAMHS have been attempting to implement this solution and increase their upper age limit beyond the 18-year cut-off, with varied results. In addition to the inertia of legal frameworks and commissioning arrangements, an important challenge to implementation has been the need to build up adequate clinical competencies, to prepare the workforce to respond to the wide range of developmental needs from childhood to young adult life. Indeed, the focus on youth psychiatry should not lead to overlook the importance of the care provided to younger, pre-pubertal populations, which is essential to ensure that prevalent psychiatric disorders with very early onset (e.g., anxiety disorders, behavioural problems) are treated timely, and that preventive interventions can effectively target early risk factors for later psychopathology4, 5. Another important feature of youth psychiatry is its increasing focus on transdiagnostic psychopathology. This transdiagnostic focus has emerged from the epidemiological evidence that psychopathology repeatedly shifts among different successive disorders over the life course1. The clinical implications of this evidence are that over-reliance on diagnosis-specific clinical protocols is unhelpful1 and that service provision should be restructured around other criteria, for example clinical staging3. Transdiagnostic models are also increasingly popular in child and adolescent psychiatry, for example to understand and address the consequences of childhood trauma5. Nevertheless, the implementation of these models presents important theoretical and practical challenges. Staging models are well established for psychosis and are increasingly emerging for bipolar, depressive and anxiety disorders4. However, staging models for truly cross-cutting, transdiagnostic constructs are still underdeveloped. In addition, development and empirical testing of transdiagnostic interventions are also in their infancy6. Establishing the validity and utility of these alternative models of psychopathology, therefore, requires further investigation prior to their widespread clinical implementation7. A third key feature of youth psychiatry is its focus on improving access to services. Youth psychiatry has promoted a "soft-entry" approach. Young people can self-refer to services, without the requirement for severity or impairment criteria, and access non-specialist, often peer-led support for mental health or psychosocial concerns. This approach has greatly benefited from co-design with young people, a positive-psychology ethos focused on strength building, and the development of technological/digital solutions. These services are less stigmatizing and more engaging for young people and have gained popularity worldwide3, including in the UK (e.g., the Fund the Hubs campaign supported by the leading mental health charities Mind and YoungMinds). By removing barriers to care access and working with the voluntary sector, youth psychiatry has championed new ways to address the vast demand for youth mental health support. However, the implementation of this "soft-entry" approach presents important challenges. To begin with, one must consider the present financial landscape. The grossly inadequate funding for CAMHS has been straining the ability to meet the raising demands from young people and their families, often limiting the focus of clinical work to only the most severe and risky cases. While the focus on prevention and early intervention in primary care can have a positive impact on the many young people with sub-threshold mental health problems4, it is important to ensure that a "soft-entry" approach can work along with, and not in competition with, CAMHS, to avoid further reduction in the treatment opportunities for young people with established psychiatric disorders. Furthermore, the implementation of a "soft-entry" approach will require a more in-depth evaluation of its safety, effectiveness and cost-effectiveness, in the same way novel interventions have been evaluated in CAMHS3, 4. In sum, there is much to gain from greater collaboration between child and adolescent psychiatry and youth psychiatry. The enthusiasm of early intervention services and the experience of CAMHS could drive a significant evolution in the mental health care provided to young people.