Authors:
Atladottir HO, Gyllenberg D, Langridge A, Sandin S, Hansen SN, Leonard H, ... Bourke J, et al.
Authors notes:
Eur Child Adolesc Psychiatry. 2015;24(2):173-83.
Keywords:
Child Development Disorders, Age Distribution, Cross-Cultural Comparison, Delivery of Health Care, Western Australia epidemiology, Population Surveillance, Autism, ADHD, OCD, Tourette Syndrome, Prevalence, Time Trend
Abstract:
The objective of this study is to compare the time trend of reported diagnoses of autism spectrum disorder, hyperkinetic disorder, Tourette's syndrome, and obsessive-compulsive disorder across four countries.
We use a population-based cohort, including all live-born children in Denmark, Finland, Sweden and Western Australia, from January 1, 1990, through December 31, 2007 and followed through December 31, 2011.
The main outcome measure is age-specific prevalence of diagnoses reported to population-based registry systems in each country.
We observe an increase in age-specific prevalence for reported diagnoses of all four disorders across birth-year cohorts in Denmark, Finland, Sweden, and (for autism spectrum disorder) Western Australia.
Our results highlight the increase in the last 20 years in the number of children and families in contact with health care systems for diagnosis and services for an array of childhood neuropsychiatric disorders, a phenomenon not limited to autism spectrum disorder.
Also, the age of diagnosis of the studied disorders was often much higher than what is known of the typical age of onset of symptoms, and we observe limited leveling off in the incidence rate with increasing age.