The associations between callous-unemotional traits and symptoms of conduct problems, hyperactivity and anxiety : a twin study
Callous-unemotional (CU) traits, such as lack of empathy, lack of guilt and shallow affect, are associated with conduct problems in youth. Research suggests that CU traits and conduct problems share common genetic factors and, possibly environmental factors. Despite evidence for a behavioural association between CU traits and hyperactivity and between CU traits and low anxiety, the etiological associations between these pairs have been considerably less explored. Objectives. Using a twin model-fitting approach, we investigated the etiological associations between CU traits and 1) conduct problems, 2) hyperactivity and 3) anxiety. Method. Participants were 204 complete pairs and 18 incomplete pairs of same-sex twins (n = 426; 42% female; 43% MZ; age = 15) drawn from the Child and Adolescents Twin Study in Sweden, a longitudinal study of twins born in Sweden. CU traits, conduct problems, hyperactivity and anxiety were assessed through self-reports. Structural equation modeling was used to conduct model-fitting analyses. Results. We found a strong positive genetic correlation between CU traits and conduct problems but no significant environmental correlations. We found a moderate genetic correlation between CU traits and hyperactivity. We also found a modest but significant negative genetic correlation between CU traits and anxiety. Conclusion. These findings suggest that common genetic factors explain CU traits and conduct problems, more particularly, and to a lesser extent CU traits and hyperactivity. In addition, these findings suggest that some of the genetic factors contributing to CU traits may also contribute to decreasing levels of anxiety.
callous-unemotional traits conduct problems hyperactivity anxiety twin study