Abstract

The aims of this study were to estimate the prevalence of autism in Northern Finland and to assess retrospectively the associations of autistic disorder with identified medical conditions and additional disabilities in this defined population of children and adolescents with autistic disorder. In order to find out the factors influencing the outcome, the methods of treatment/habilitation and the interventions used were studied in detail. The last aim was to elicit reliable information for decision-makers as well as ideas for giving support and, because of the presumed better outcome, saving resources in the long run.

The data were collected from hospital records and the records of the central institutions for the intellectually disabled in the Provinces of Oulu and Lapland in 1996–1997. The age-specific prevalences obtained in this study showed the prevalence to be lowest, i.e. 6.1 per 10 000, in the oldest age group of 15- to 18-year-old adolescents and highest, i.e. 20.7 per 10 000, in the age group of 5- to 7-year-old children, when the criteria of ICD-10 and DSM-IV were used. In this study, almost 50% of the autistic cases had a tested IQ above 70. Associated medical disorders or associated disorders of known or suspected genetic origin were diagnosed in 12.3%. Other associated medical disorders were epilepsy, hydrocephalus, fetal alcohol syndrome and cerebral palsy. Severe impairment of vision was evident in 3.7%. The most common therapies were physiotherapy and speech, occupational and music therapy. 43.9% of the children and adolescents with autism received specific training according to the TEACCH (Treatment and Education of Autistic and related Communication-Handicapped Children), 10.2% according to the Lovaas and 30.5% according to the Portage program. Antiepileptic medication had been prescribed to 23.9% and psychopharmacals to 14.9% of the individuals with autistic disorder (AD).

About three- to fourfold prevalence of AD in Northern Finland was found when compared to 16 years ago. Early, effective and regular interventions in autism have a good impact and should be provided as early as possible to children with autism. Based on the poorer prognosis of those without any early intervention, it can be anticipated that these methods will save resources in the long run.