Trajectories of callous–unemotional traits from childhood to adolescence in referred youth with a disruptive behavior disorder who received intensive multimodal therapy in childhood

Gabriele Masi,¹ Simone Pisano,² Paola Brovedani,¹ Gioia Maccaferri,¹ Azzurra Manfredi,¹ Annarita Milone,¹ Annalaura Nocentini,³ Lisa Polidori,¹ Laura Ruglioni,¹ Pietro Muratori<sup>1

1</sup>IRCCS Fondazione Stella Maris, Scientific Institute of Child Neurology and Psychiatry, Calambrone, Italy; ²Clinic of Child and Adolescent Neuropsychiatry, Department of Medicine and Surgery, University of Salerno, Baronissi, Italy; ³Department of Sciences of Education and Psychology, University of Florence, Florence, Italy

Purpose: Our aims were to explore the developmental trajectories of callous–unemotional (CU) traits using a growth curve analysis in Italian children with disruptive behavior disorders treated with a multimodal intervention, and to test both predictors and distal outcomes of CU traits trajectories.
Patients and method: One hundred and sixty-eight children were enrolled, of whom 24 were lost in the follow-up and 144 were followed up from ages 8–9 to 14–15 years with four assessment points. Patients included 128 males (88.9%) with a mean age of 8.7 years, 96 with oppositional defiant disorder (66.7%) and 48 with conduct disorder (CD) (33.3%). The developmental trajectories of CU traits were assessed with the Inventory of Callous–Unemotional Traits (ICU).
Results: Our findings revealed that CU features were likely to fit a quadratic model from childhood to adolescence. The CU traits tended to decrease during childhood, with stabilization in adolescence and a significant variability in the growth curves. Pretreatment CD and higher levels of externalizing behavioral problems were associated with higher level of CU traits at baseline, whereas positive parenting was associated with lower levels. No significant effects were found for all the other predictors (socioeconomic status, negative parenting, combined pharmacotherapy). Regarding outcomes into adolescence, both higher levels of CU traits at the baseline and a lower decrease of CU traits across time points predicted a higher risk of CD diagnosis, and higher rate of referrals to mental health services and of substance use. Furthermore, pretreatment CD and negative parenting predicted a higher risk of substance use into adolescence.
Conclusion: Our findings suggest that a close monitoring of CU traits in referred children with disruptive behavior disorders may help to detect the patients at higher risk of poor outcome.

Keywords: conduct disorder, oppositional defiant disorder, callous–unemotional traits, aggressive behavior, child psychiatry, psychopathy