An article in The Journal of Child Psychology and Psychiatry published in December of 2011 is entitled “Prevalence of Psychiatric Disorders in Preschoolers.”  The authors are based out of Norway, and they evaluated over two thousand children born in 2003 or 2004 in the city of Trondheim, Norway at the age of four using the Strengths and Difficulties questionnaire.  They found an estimated population rate of psychiatric illness of 7.1%.  The authors state:

“The most common disorders were attention deficit hyperactivity disorder (1.9%), oppositional defiant disorder (1.8%), conduct disorder (0.7%), anxiety disorders (1.5%), and depressive disorders (2.0%). Comorbidity among disorders was common. More emotional and behavioral disorders were seen in children whose parents did not live together and in those of low socioeconomic status. Boys more often had attention-deficit/hyperactivity disorder (ADHD) and depressive disorders than girls.”

What are most commonly reported as adult psychiatric disorders, typically have their onset in childhood and adolescence.  Often a parent or teacher will readily identify behavior problems that are indicators of underlying psychological dysfunction.  Depression, anxiety disorders and attention deficit/hyperactivity are identifiable even down to four years of age.  Previous studies typically evaluate children around ages 8 to 9 and older. This Norwegian study finds a somewhat lower incidence of mental health issues in children when compared to studies in the United States, which report a 10-20% incidence.  Some disorders may have onset in childhood, and then wax and wane throughout life.  Others may have a later onset.  For example, depression more typically arises in older children, predominantly in females, at the age of adolescence when hormonal changes are occurring.  Some psychological problems may also occur later in life and not be apparent in preschool children.

This study shows there are important opportunities to identify and even diagnosis psychological illness in preschool children. This would allow early implementation of therapeutic strategies and family psychoeducation, to help modulate these children, and minimize the effects of underlying psychological dysfunction as they grow into adolescence and adulthood.

Prevalence of psychiatric disorders in preschoolers
Lars Wichstrøm, Turid Suzanne Berg-Nielsen, Adrian Angold, Helen Link Egger, Elisabet Solheim1, Trude Hamre Sveen

Journal of Child Psychology and Psychiatry, 29 DEC 2011, DOI: 10.1111/j.1469-7610.2011.02514.x

Preschool psychopathology: lessons for the lifespan
Journal of Child Psychology and Psychiatry 48:10 (2007), pp 961–966 doi:10.1111/j.1469-7610.2007.01832.x  Adrian Angold and Helen Link Egger
Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, USA

Prevalence and Development of Psychiatric Disorders in Childhood and Adolescence

E. Jane Costello, PhD; Sarah Mustillo, PhD; Alaattin Erkanli, PhD; Gordon Keeler, MS; Adrian Angold, MRCPsych
Arch Gen Psychiatry. 2003;60:837-844.