A Study on nosology and prognosis of autistic disorder

Tomoko SUGANO1), Akiko YOSHIDA1), Takeshi MATSUISHI1), Keiko ENDO2)

1) Yokohama National University, Faculty of Education and Human Sciences
2) Yokohama City University, School of Medicine, Department of Psychiatry

It is sometimes difficult to capture the clinical picture of autistic individuals and children, mainly because signs and symptoms can vary from one patient to another, and they also change according to age. Therefore, surveys were conducted in this study targeting parents of autistic individuals and children, regarding their signs and symptoms, keeping in mind changes through time. According to their symptoms we classified in subgroups (sub classification) and cleared up these subgroup's characteristic in symptomatic period and adolescent period. In addition to that, we study the change pattern of symptoms in the course of their growth. Study subjects included 89 mentally retarded autistic individuals (73 male and 16 female) who visited the Yokohama City Health and Social Welfare Center or the Kanagawa Prefectures Health and Social Welfare Center between October 1994 and October 1995. Their ages ranged from 17 to 30 years old, with a 19.6 years mean.
The method of study is to be performed by a questionnaire survey of the parent of autistic patients. Patient's parents answered 30 questions based on the DSM-III-R diagnostic criteria. The survey focused on the current stage (adolescence) of the individual and the most difficult stage the parents had faced (most symptomatic phase). The data obtained was analyzed using continuous multivariate analysis of Japanese type 3 multivariate quantification methods and Cluster analysis for both stages. According to the results, the most symptomatic stage corresponds to ages between 3 and 8, followed by those between 13 and 15. Through statistical processing the most symptomatic phase was classified in 3 subgroups. Subgroup 1 included individuals with symptoms specific to DSM-III-R's areas A, B, and C. It means that they noticeably show every aspects of autism symptoms. That is to say, this is group with the most severe symptoms. Subgroup 2 included individuals with symptoms specific to DSM-III-R's area A, and social interaction problems with a segregated tendency. Individuals in subgroup 3 had symptoms specific to DSM-III-R's area B characterized by interpersonal communication difficulties due to language impairments such as unilateral discourse or phrase repetition. However, they are interested in relating to others. Subgroup 1 represented 50.6% of the population, subgroup 2: 23.6%, subgroup 3: 7.8%, and 18.0% were no classifiable. Likewise, adolescent individuals (those 18 years of age or older) were also divided into subgroups using the same quantitative method. Subgroup 1 in the adolescence stage displays the same characteristics as subgroup 1 in the most symptomatic stage. On the other hand, adolescent subgroup 2 was different from subgroup 2 in the most symptomatic stage. This group included individuals with DSM-III-R's area C symptoms: repetitive actions, perseverative tendency, conservation of the same state etc. Adolescent subgroup 3 has fewer symptoms. A common characteristic is echolalia. Subgroup I was reduced during adolescence to 10.1%, subgroup 2: 36.0%, and subgroup 3: 34.8%. 19.1% of cases were unclassifiable. About half of subgroup 1 during the most symptomatic stage switched to subgroup 2 during adolescence, and one-third to subgroup 3. Around 40% of subgroup 2 during the most symptomatic stage 40% remained in subgroup 2 during adolescence, and 40% switched to subgroup 3. As for subgroup 3 during the most symptomatic stage, they remained in subgroup 3 during adolescence. The general tendency is for autistic individuals with DSM-III-R's area A, B, and C symptoms to improve from half to 10%, those with area B and C symptoms tend to increase relatively. A comparison was made between these results with Wing's classification (1974), and other studies by Siege (1986), Eaves (1994), and O'brien (1996). We found the same to some extent but also the inconcordances because of the differences of sample and anylizing method. We studied on symptom changes according to age. Autism symptoms change with age and in general, improve. However, when considering problems arising after adolescence, such as employment, patients face new and diverse difficulties. In conclusion, autism could be divided into subgroups according to symptoms. It was also confirmed that autism symptoms change over time. Therefore, we would like to emphasize on the importance of obtaining a precise picture of symptoms of individual autistic according to the stage, taking into account long term changes and also to put those to account in education, medical care and social welfare for autistic patients.
(originally published in Journal of Disability and Medico-Pedagogy Vol.8.2003 p9-10).