A recent study of more than 700,000 children discovered a significant increase in the diagnosis of three out of four mental disorders over nine years. Autism, autism spectrum disorder, Tourette’s and attention deficit disorder diagnoses in children increased, while obsessive-compulsive disorder diagnoses decreased.
Researchers from the University of Aarhus collected data from the Danish National Psychiatric Registry on the mental health of every child born between 1990 and 1999. The Danish researchers say it is not clear if the apparent rise is real and caused by environmental factors or whether it is due to increased awareness and diagnosis of child mental health problems by doctors.
While the study did not address the causes of the increases in the other three problems, its authors concluded it was clear “that the number of children with neuropsychiatric disorders and their families in need of support and services has been growing in recent years.”
Diagnosis of attention deficit disorder (called by its European name in the study, hyperkinetic disorder) at the age of five nearly tripled between 1992 and 1999. Tourette syndrome more than doubled between 1990 and 1995.
Diana Schendel, of the Centers for Disease Control in Atlanta, Georgia, and part of the team that produced the study, said: “The autism trend has been reported in a lot of other studies and it has been a big focus of interest. What this shows is that in fact the apparent rise in autism might not be a solitary event. We do see a similar pattern of increase in these other conditions.”
The research was published in the Archives of Paediatric and Adolescent Medicine.
Despite many studies showing that diagnoses of autism are rising, the reasons for the increase are still not clear. One study in 2005 suggested it was due to better diagnosis. British researchers screened every child in the county of Staffordshire born between 1992 and 1995 for autism — 15,500 children in total. They then did the same for children born between 1996 and 1998, using the same diagnostic criteria. The prevalence of autism stayed roughly the same, at 62 children per 10,000, suggesting the rate of autism stayed the same, but doctors were getting better at diagnosing it.