Diagnostic trajectories and stability of mental disorders in childhood and adolescence - a nation-wide cohort study using sequence analysis

BACKGROUND: Little is known about the diagnostic trajectories following a first psychiatric diagnosis in childhood or adolescence. Such knowledge could aid clinicians in treatment, risk prediction, and psychoeducation. This study presents a comprehensive nationwide overview of diagnostic trajectories in children and adolescents after their first diagnosis in child and adolescent psychiatric hospitals.

METHODS: Patients aged 0 to 17 years who received their first psychiatric diagnosis between January 1996 and December 2011 were identified through the Danish National Patient Registries. Shifts at the International Classification of Diseases (ICD-10) two-cipher level (F00-F99), grouped into 19 categories, were identified. Subsequent diagnoses during 10 years of follow-up until December 2021 were identified and analyzed using state sequence analysis and Cox proportional hazard regression models.

RESULTS: A total of 77,464 children and adolescents (32,733 [42.26%] girls) were identified with a first-time psychiatric diagnosis. Among these, 46.7% of girls and 37.6% of boys had at least one diagnostic shift after 10 years of follow-up. High entropy and low diagnostic stability were found in first-time diagnoses often presenting in adolescence, such as affective disorders, psychotic illness, and personality disorders, while lower entropy and high diagnostic stability were found in neurodevelopmental disorders and eating disorders. For most categories, girls had higher mean entropy measures than boys (P < 0.05).

CONCLUSIONS: Diagnostic shifts are common in child and adolescent psychiatric services, particularly when the first contact occurs in adolescence. Adequate focus on psychoeducation about emerging diagnostic shifts, and on timely detection, particularly in girls, and particularly in adolescence, is warranted.