Psychiatric comorbidities in children with conduct disorder: a descriptive analysis of real-world data

To the editor: Two recent advisories from the US surgeon general have underscored the unprecedented public health crisis in youth mental health and emphasised the need for “timely data collection and research to identify and respond to youth mental health needs more rapidly”.1 Increased rates of suicidal behaviour, depression and anxiety symptoms and substance use, particularly in adolescents and young adults, are part of an emerging landscape of high volumes of emergency room visits and hospitalisations for behavioural problems.2 3 Conduct disorder (CD) has emerged as an increasingly common presenting concern in adolescents and young adults receiving emergency and inpatient psychiatric care.4–6 Yet, CD remains among the least studied of paediatric psychiatric disorders, even though it is thought to be associated with a myriad of devastating social, legal and psychiatric consequences that may persist into adulthood and is frequently comorbid with other psychiatric disorders.7 Although recent studies estimate that CD affects approximately 2%–3% of the school-aged paediatric population worldwide,8 ambiguity remains about its association with other psychiatric conditions. CD is posited to be associated with increased rates of anxiety, depression, substance use and attention-deficit hyperactivity disorder (ADHD), as well as other externalising disorders, with a multisite analysis in Europe examining nearly 800 children with CD and found that more than one-third likely suffered from current ADHD symptoms and over three-fourths suffered from oppositional defiant disorder symptoms.9 Yet, estimates of comorbidity based on clinical data collected in settings that reflect actual psychiatric care, particularly in the USA, are lacking. Furthermore, many of the estimates of psychiatric comorbidity in adolescents and young adults, defined as ages 12–25, with CD, were conducted >10 years ago, preceding the ongoing paediatric mental health crisis in the USA. Untreated co-occurring psychiatric conditions in adolescents and young adults with behavioural disorders …