Non-right-handedness and mental health problems among adolescents from the general population: The Trails Study

Abstract

To determine whether the association between non-right-handedness and mental problems among adolescents is specific for psychotic symptoms, we included a group of 2096 adolescents with a mean age of 14 years from the general population. Mental health problems were assessed using the parent, self-report, and teacher versions of the Child Behavior Checklist. Internalising problems comprised anxious and depressed, withdrawn and depressed, and somatic complaints. Externalising problems consisted of delinquent behaviour and aggressive behaviour. The remaining problems consisted of social problems, attention problems, and thought problems. The latter were divided into psychotic and non-psychotic items. A total of 14.3% of the adolescents were non-right-handed. We observed positive associations of non-right-handedness with thought problems, social problems, and being withdrawn and depressed. Externalising problems showed no associations with handedness. Within the thought problems subscale, the effect sizes associated with non-right-handedness for psychotic and non-psychotic items were 0.18 (p=.005) and 0.04 (p=.459), respectively. In conclusion, non-right-handedness is predominantly associated with psychosis-related mental problems as early as in adolescence. Handedness could be taken into account when identifying adolescents at risk for psychosis.

Keywords:

• Handedness
• Mental health problems
• Psychosis

Acknowledgements

This research is part of the TRacking Adolescents' Individual Lives Survey (TRAILS). Participating centres of TRAILS include various departments of the University Medical Centre and University of Groningen, the Erasmus University Medical Centre Rotterdam, the University of Utrecht, the Radboud Medical Centre Nijmegen, and the Trimbos Institute, all located in the Netherlands. Principal investigators are Prof. Dr J. Ormel (University Medical Centre Groningen) and Prof. Dr F. C. Verhulst (Erasmus University Medical Centre). We are grateful to all adolescents, their parents and teachers who participated in this research and to everyone who worked on this project and made it possible.

TRAILS has been financially supported by various grants from the Netherlands Organization for Scientific Research NWO (Medical Research Council program grant GB-MW 940-38-011; ZonMW Brainpower grant 100-001-004; ZonMw Risk Behavior and Dependence grants 60-60600-98-018 and 60-60600-97-118; ZonMw Culture and Health grant 261-98-710; Social Sciences Council medium-sized investment grants GB-MaGW 480-01-006 and GB-MaGW 480-07-001; Social Sciences Council project grants GB-MaGW 457-03-018, GBMaGW 452-04-314, and GB-MaGW 452-06-004; NWO large-sized investment grant 175.010.2003.005); the Sophia Foundation for Medical Research (projects 301 and 393), the Dutch Ministry of Justice (WODC), and the participating universities.