Referral pattern and special interests in children and adolescents with Asperger syndrome: a Turkish referred sample

Abstract

Objectives:

To investigate the most frequent reasons for referral, the most common special interests, age at first referral to a mental health service, and the age of diagnosis in children and adolescents with Asperger syndrome living in Turkey.

Methods:

This study includes 61 children and adolescents diagnosed with Asperger syndrome using strict DSM-IV criteria.

Results:

The mean age at first referral was 7.9 whereas the mean age when Asperger syndrome was diagnosed was 9.9, which is compatible with other studies. The most frequent reasons for the first referral were attention deficits, hyperactivity, and academic failure, and the most common special interest area was “electronic devicess, computer, and technical interests.”

Conclusions:

The types of special interests and referral reasons in our Asperger syndrome sample are very similar to the interest areas and referral reasons of individuals with Asperger syndrome from developed western countries indicating the universality of symptoms. It could be concluded that children and adolescents with Asperger syndrome may refer to mental health services with a variety of symptoms; therefore, it is important to make a detailed assessment of social difficulties especially in school-age children and adolescents for the differential diagnosis of Asperger syndrome.

Keywords

Asperger syndrome children diagnosis interests referral

Introduction

Asperger syndrome (AS) or “autistic psychopathy”—as the syndrome was originally termed by Hans Asperger—is a pervasive developmental disorder (PDD) characterized by social impairment and restricted interests and behaviors (American Psychiatric Association (APA), 1994). Before its introduction in the International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10) (World Health Organization (WHO), 1992) and Diagnostic and Statistical Manual of Mental Disorders–Fourth Edition (DSM-IV) (APA, 1994), AS tended to be conceptualized as a mild form of autism or a manifestation of autism in people of normal intellectual ability. In contrast to autistic disorder (AD), language development in AS is not supposed to be delayed and normal cognitive and self-help skills need to present during the first 3 years of life according to DSM-IV. However, it is still an ongoing debate whether AS is different from high-functioning autism (Klin and Volkmar, 2003).

At early ages, the problems of AS are mostly obscured by the specific strengths that are often associated with the disorder, and parents may overlook social impairment, when the child at first seems more advanced than his or her peers (Frith, 2004). In addition, the characteristic symptoms of the syndrome are usually presented around school age. Therefore, the diagnosis of AS is rarely made before school age (Gillberg, 2002). However, recently developed screening instruments may be helpful in detecting younger children in the autism spectrum with normal intelligence (Williams et al., 2005).

It is seldom that individuals with AS are referred only for their social and communication deficits. Although the authors and studies from developed western countries emphasize that individuals with AS are referred mostly because of the presence of disabling symptoms, such as hyperactivity, physical aggression, and depression, there is no systematic study that investigated the referral pattern of individuals with AS in a developing non-western country, to our knowledge (Ghaziuddin, 2002; Raja and Azzoni, 2001).

Authors and studies from developed western countries mention that these individuals may have talents or interests in areas such as computers, electronic devices, geography, history, science, mathematics, meteorology, and sports results (Attwood, 2007; Ghaziuddin, 2005; Gillberg, 2002). However, there is no information regarding the areas of interest of this group from different cultures.

The present study aimed to assess the following: (a) the most frequent reasons for referral, (b) the age at first referral to a mental health service and the age of AS diagnosis, and (c) the most common special interests of this group in a middle-income developing country and to compare the results with studies from developed western countries.

Method

Participants

Participants were 66 children and adolescents with a diagnosis of AS who were recruited from the Autism Clinic of the Child and Adolescent Psychiatry Department at the Istanbul School of Medicine, Istanbul University. The data belonged to all the cases that were examined in the Autism Clinic between September and December 2009. Most of the cases were already at follow-up for years. The patients with a definite or suspected diagnosis of AS were first assessed by the first author (C.T.) who now has about 7 years of clinical experience working with individuals in the autism spectrum. The patients who were diagnosed with AS by the first author were reassessed by the senior author (N.M.M.), who is an expert on autism spectrum disorders for the confirmation of the diagnoses. The senior author (N.M.M.) reexamined all the participants by interviewing the child and the parents using DSM-IV criteria and the final diagnoses were made. Four patients were excluded from the study because of low IQ (IQ < 70) and one was excluded because the senior author decided that the exact diagnosis was PDD–not otherwise specified. Therefore, the information was gathered from 61 cases.

Diagnosis

The AS diagnosis was made using the DSM-IV criteria. Diagnoses were based on the comprehensive information from clinical examination, which included interviews with the parent and child, and reviewing previous psychiatric, psychometric, and educational records. In order to avoid diagnostic uncertainty, the DSM-IV hierarchy of PDD was strictly applied. According to the precedence rule, the diagnosis of AD was considered first. AS diagnosis was made if the participant did not meet DSM-IV criteria for AD.

Inclusion criteria

The following were the inclusion criteria for this study:

Diagnosis of AS according to DSM-IV criteria

Consensus for the diagnosis of AS by at least two child and adolescent psychiatrists

Parent’s informed consent and patient’s assent

Exclusion criteria

The following were the exclusion criteria for this study:

Presence of former AD diagnosis

IQ < 70 (full-scale IQ)

Uncertainty of parents about time of language development

Assessment of intellectual abilities

The Turkish version of the Wechsler Intelligence Scale for Children–Revised (WISC-R) was administered. All cases had full-scale IQ scores higher than 70.

Clinical data

The clinical data were gathered using a form prepared by the authors. The form covered the parental education level, socioeconomic status of the family, developmental history of the child, age at which parents first referred to a mental health service (including psychologists, special education specialists, psychiatrists, and child and adolescent psychiatrists), the main reasons for the first referral, the age when the AS diagnosis was confirmed, and the most common special interest or interests of the child. Psychiatric comorbidity was assessed using the Schedule for Affective Disorders and Schizophrenia for School Age Children–Present and Lifetime Version–Turkish Version (K-SADS-PL-T). The K-SADS-PL is a semistructured interview schedule designed to assess 32 psychiatric disorders in children and adolescents on the basis of DSM-IV criteria (Kaufman et al., 1997). The K-SADS-PL-T was used in this study. The translator demonstrated the reliability and validity of this version (Gokler et al., 2004). All the interviews were conducted by the authors.

According to the DSM system, the diagnoses of attention deficit hyperactivity disorder (ADHD), separation anxiety disorder (SAD), social phobia (SP), and generalized anxiety disorder (GAD) are to be avoided in individuals with PDD. However, in the present study, the existence of PDD as an exclusion criterion for any DSM-IV diagnosis was not applied during the K-SADS-PL-T administration.

Ethics

The study was approved by the Medical Ethics Committee of the Istanbul School of Medicine, Istanbul University. Parents of all children had signed informed consent forms prior to participation in the study. In addition, children older than 12 years signed the consent forms themselves.

Statistical analysis

Age, IQ, and the clinical data were shown as mean, range, or percentages. A non-parametric test (Mann–Whitney U) was used to compare mean age of first referral and mean age of diagnosis between girls and boys. A probability level of p < 0.05 was used to indicate statistical significance. Data were analyzed using the Statistical Package for the Social Sciences (SPSS), version 16.0 (SPSS, Inc., Chicago, IL, USA).

Results

In total, 61 children and adolescents with AS (56 boys and 5 girls) were included in the study. Our clinic offers as primary, secondary, and tertiary mental health services, and most of the cases were referred from our general outpatient clinic. For a few of the cases, our clinic was the second place for referral and children were assessed by a prior mental health professional. Most of the referrals were through self-seeking help of the parents. A few of the referrals were from outside Istanbul. The mean age of the sample was 11.16 years (standard deviation (SD): 3.53, range: 6–17) and the mean full-scale IQ score was 107.98 (SD: 15.74, range: 70–139). The age, IQ scores, and developmental milestones of the participants are shown in Table 1.

Table 1.

Characteristics of the AS sample.

	Mean (SD)	Range (minimum–maximum)
Current age (years)	11.16 (3.53)	6–17
Verbal IQ	114.31 (15.01)	79–141
Performance IQ	103.19 (1.03)	76–137
Full-scale IQ	107.98 (15.74)	82–139
Walking (months)	13.93 (0.57)	8–19
First words (months)	14.37 (1.02)	7–24
Sentences (months)	24.03 (1.34)	12–36
Age at the first referral (years)	7.95 (3.75)	2–16
Age of the diagnosis of AS (years)	9.89 (3.66)	4–16

AS: Asperger syndrome.

A total of 82% of the mothers and 77.5% of the fathers of the participants graduated from a high school or a university, which is a high educational level for Turkey. Socioeconomic statuses of the families were assessed as 30% in the high-income group, 60% in the middle-income group, and 10% in the low-income group.

Age at first referral and age at diagnosis

The mean age at the first referral was 7.9 years (minimum: 2 years; maximum: 16 years), and the mean age of diagnosis for AS was 9.9 years (minimum: 4 years; maximum: 16 years) (Table 1). There was no statistically significant difference between girls and boys regarding the first referral age and diagnosis age. The mean age at the first referral was 6.3 years (minimum: 2 years; maximum: 15 years) for girls and 8.1 years (minimum: 3 years; maximum: 16 years) for boys (p = 0.18). The mean age of diagnosis for AS was 8.5 years (minimum: 5 years; maximum: 15 years) for girls and 10.0 years (minimum: 4 years; maximum: 16 years) for boys (p = 0.36). Given the small number of girls (n = 5, 8%) in the overall sample, although the results regarding age of first referral and diagnosis age were not statistically different between boys and girls, nevertheless this observation may reflect an important trend. The girls were almost 2 years younger than the boys at first referral and 1.5 years younger at diagnosis. A total of 24 cases (39%) were diagnosed with AS at their first referral to a psychiatry clinic. All these 24 cases received this diagnosis in our clinic in a few weeks after completion of the diagnostic evaluation. The maximum time passed until AS diagnosis made was 9 years. In total, 15 children (25%) were below 6 years of age when their parents first sought psychiatric help.

Reasons for first referral

The most frequent reasons for the first referral consisted of attention deficits, hyperactivity, and academic failure, followed by difficulties in socialization and interaction with peers (Table 2). In 25 of the cases, there were multiple reasons for referral. Below 6 years, the most frequent reason was difficulties in socialization and interaction with peers. Only in 11 cases the main and the only reason for referral was the difficulties specific to the syndrome, for the remaining it was other behavioral problems. The most frequent reason for the first referral was “attention deficits, hyperactivity, and academic failure” for boys and “difficulties in socialization and interaction with peers” for girls.

Table 2.

Reasons for referral.

	n	(%)
Attention deficits, hyperactivity, and academic failure	23	40
Difficulties in socialization and interaction with peers	17	29
Aggressive behavior and opposition	10	17
Depressive mood, withdrawal, and mood swings	7	12
Anxiety attacks and phobia	6	10
Obsessive and compulsive behaviors and stereotypes	6	10
Problems in language development	4	7
Tics	2	3
Special interests and skills	2	3
Sleep problems	2	3

Occasionally reported reasons for the first referral included motor coordination problems, school absenteeism, difficulty in understanding abstract ideas, and frequent imagination.

Special interests

The most common special interest area was “electronic devices, computer, and technical interests” for the whole group and also for boys (Table 3). The second most common special interest area was “history, geography, and science”. Interest areas and referral reasons of girls are shown in Table 4. In 25 cases, there were two special interests at the same time.

Table 3.

Special interests.

	n
Electronic devices, computer, and technical interests	25
History, geography, and science	20
Cars	8
Football	6
Animals, flowers, and nature	6
Foreign language (especially English)	4
Movies	4
Philosophy and politics	3
Mathematics and numbers	2
Imagining and fantasies	2

Table 4.

Referral reasons and special interests of girls.

Referral reasons	n	Special interests	n
Difficulties in socialization and interaction with peers	2	Animals, flowers and nature	1
Depressive mood, withdrawal, and mood swings	1	Foreign language (especially English)	1
Aggressive behavior and opposition	1	Philosophy and politics	1
Obsessive and compulsive behaviors and stereotypes	1	Mathematics and numbers	1
Problems in language development	1	Movies	1
		Music	1

Occasionally reported special interests were music, cartoon heroes, war planes, writing–drawing, holiday plans, and playing Lego.

Psychiatric comorbidity

The most common comorbid diagnostic group was anxiety disorders. The second most common comorbid diagnostic group was disruptive behavior disorders. Comorbid psychiatric disorders are shown in Table 5.

Table 5.

Rate of comorbid psychiatric disorders.

Diagnosis	n	%
Anxiety disorders	40	66
Disruptive behavior disorders	36	59
Mood disorders	24	39
Tic disorders	16	26
Elimination disorders	8	13
Psychotic disorders	1	2

Discussion

To our knowledge, the present article is the first clinical study that assessed the referral pattern and special interests in a significant number of children and adolescents with AS from a middle-income developing country.

The results are discussed in detail and compared with the results of studies from developed western countries in the following section.

Age at initial referral and age at diagnosis

It is hard to compare our results concerning the initial referral age with that of the previous studies because of methodological differences. We sought the referral age to a mental health service and found a mean age of 7.9 years. However, Hippler and Klicpera (2003) analyzed the case records of “autistic psychopaths” diagnosed by Hans Asperger and his team, and reported the mean age of first referral to the remedial pedagogical ward as 8 years. However, any prior referral to a mental health service before this pedagogical ward was not mentioned. Another study surveyed parents of children with autism and AS and found that the mean age of children with AS was 3.5 years when their parents sought diagnostic consultation for the first time (Howlin and Ashgarrian, 1999). However, the first professionals from whom parents sought help were their general practitioner or health visitor and in a few of them a pediatrician.

The mean age of AS diagnosis in our study (9.9 years) is compatible with that of other studies from developed western countries. Howlin and Ashgarrian (1999), Cederlund and Gillberg (2004), and Belkadi et al. (2003) found the average age of diagnosis as 11 years, 11 years 4 months, and 10 years, respectively. There is a difference of approximately 2 years between the mean age of first referral to any mental health professional and mean age of diagnosis in our study group. Only 39% of the participants were diagnosed with AS during the first referral after the completion of the diagnostic evaluation in a few weeks, and all these participants were from our university’s outpatient clinic. It seems that although child psychiatrists, especially in university settings, are more familiar with the diagnosis of AS, in other settings, there is still a lack of awareness in Turkey among mental health professionals.

Reasons for first referral

In this study, only two-fifth of the parents of cases were aware of the problems specific to the syndrome such as social difficulties, compulsive behaviors, and stereotypes when they sought for psychiatric help for the first time. In half of these cases, the core symptoms of the AS were the main and the only reason, whereas the remaining described additional disabling symptoms. These findings are compatible with the literature that for most individuals with AS, the initial presentation to a mental health setting included symptoms such as hyperactivity, physical aggression, and depression not the core symptoms of the syndrome (Ghaziuddin, 2002).

In our study, the most common reason for referral in preschool children was the core symptoms of AS, whereas attention problems and academic issues dominated for school-age children. An explanation for this may be that some children might have more severe symptoms from the beginning and come to clinical attention earlier or when these children have first attended school, parents may have been more concerned about academic issues and other comorbid conditions than social deficits. A similar finding was found also for the girls. Most of the referral reasons of girl participants consisted of symptoms associated with the syndrome itself. Probably girls with severe symptoms come to clinical attention and many other girls with the syndrome have missed diagnosis. This may also explain the low number of girl participants in this study. In addition, it was a striking finding that no girl was referred because of attention deficits, hyperactivity, and academic failure, which were the most common reasons for referral in boys.

The most common reason for the first referral in the whole group was ADHD symptoms. It is compatible with the study of Hippler and Klicpera (2003) and with the results of studies on comorbidity pattern in this group (Ghaziuddin et al., 1998; Mukaddes and Fateh, 2009). Hippler and Klicpera (2003) found that the most frequent reasons for referral of Hans Asperger’s cases were learning difficulties, attention deficits, and academic problems. Our previous studies along with studies from other centers with clinical referred groups report a very high rate (29%–66%) of comorbidity between these two disorders, and therefore, clinicians should carefully assess the individuals with ADHD for the presence of autism spectrum symptoms (Ghaziuddin et al., 1998; Mukaddes et al., 2010; Mukaddes and Fateh, 2009).

Aggressive behavior and opposition was the third most common reason for the first referral similar to the participants described by Asperger (Hippler and Klicpera, 2003). In addition, in many comorbidity studies, oppositional defiant disorder was found to be a common disorder in children and adolescents with AS (Mukaddes et al., 2010). Anxiety and depressive symptoms and obsessive–compulsive behaviors were also common reasons for referral in our study. Typically, individuals with AS have characteristics that can mimic symptoms of obsessive–compulsive disorder (OCD) or they may have a comorbid OCD (Bejerot, 2007; Russell et al., 2005). In one case, the referral reason was school absenteeism but a comprehensive assessment revealed that the reason of school absenteeism was depression. Comorbidity studies agree that anxiety disorders, mood disorders (especially depression), and OCD are common comorbid disorders in individuals with AS (Ghaziuddin et al., 1998; Mukaddes et al., 2010; Mukaddes and Fateh, 2009).

This study also replicated the results of comorbidity studies of individuals with AS. The results show that anxiety disorders, disruptive behavior disorders, and mood disorders were the most common comorbid psychiatric disorders, which is compatible with the findings of comorbidity studies mentioned above.

Special interests

“Electronic devices, computer, and technical interests” was the most common special interest area in our cases. This finding confirms the suggestion of Baron-Cohen (1997) that there may be a link between autism spectrum conditions and engineering or superior functioning in the domain of “folk physics” (an interest in how things work). Baron-Cohen and Wheelwright (1999) found that children with autism and AS show significantly more obsessional interests in the area of folk physics.

Furthermore, a study of 1000 families showed that fathers and grandfathers (patrilineal and matrilineal) of children with autism or AS were more than twice as likely to work in the field of engineering, compared to control groups. The authors concluded that this finding may reflect that the genes shared by both parents and their child with an autism spectrum condition shape the brain toward interests in folk physics (Baron-Cohen et al., 1997).

Special interests of girls were relatively more social such as music and movies, which is compatible with the findings of authors from western countries (Attwood, 2007; Gillberg, 2002). Gillberg (2002) states that “girls’ interests may sometimes, at least superficially, appear to be more ‘social’, but, on further analysis they are dependent on rote memory rather than meaning”. Using psychometric definitions of the typical male and female brains, Baron-Cohen et al. (2005) observed that people with autism spectrum conditions show an exaggeration of the male profile. This is one of the major components of their “extreme male brain (EMB) theory,” which was first formulated by Hans Asperger as a clinical anecdote. However, in this study, we found that girls’ interest areas were more social, which seems to conflict with this theory.

“History, geography, and science” was the second most common special interest. “Cars” and “animals, flowers, and nature” were the following common interest areas. It is compatible with the interest areas of individuals with AS mentioned by authors from developed western countries and Hans Asperger’s cases. Interestingly, “football (soccer in USA)” was a common special interest in our study and not mentioned as a common interest area in AS by the western literature. It may be a cultural difference or a contemporary interest area. Typically developing male children and adolescents are also very much interested in cars and football in our country, but the children with AS were much more interested in memorizing facts such as all the match scores or details of hundreds of football players, although they themselves did not play football at all.

Although there seem to be some possible cultural differences, the main special interest areas (electronic devices, computer and technical interests, and scientific interests) found in our study are similar to those reported from western countries.

Conclusion

The results of our study suggested that the type of special interests and referral reasons in our AS sample are very similar to those from developed western countries, indicating the universality of the symptoms.

Another conclusion that can be drawn from this study is that comorbid problems may obscure the clinical picture of AS, so that a correct diagnosis may be missed for years. Therefore, it is important to make a detailed assessment of social difficulties in any school-age child and adolescent who is referred for psychiatric help. Differential diagnosis of AS in children and adolescents with other psychiatric disorders seems crucial in establishing an effective treatment program, and therefore improving mental health outcomes.

The strengths of the study

This is the first clinical study that examined the referral pattern and special interests in individuals with AS from a middle-income developing country. In addition, the study includes high number of children and adolescents with AS and the data was gathered by comprehensive clinical examinations and interviews with both the parent and the child.

Methodological limitations

This study was conducted in one of the largest developmental disabilities child psychiatry clinics in Turkey and most of the parents had a high educational level, and therefore, referral bias is inevitable. The study involves a clinical sample with selection bias and various referral sources, and generalization for the country at large will at best be highly presumptive. There are also significant disparities in the availability of child mental health services, especially, in geographic and rural regions where parent educational level is lower.

First, for some cases, our university’s outpatient clinic (a clinic which has good experience with autism spectrum disorders) was the first place for initial referral, and therefore, these cases were immediately diagnosed with AS. This may have influenced the mean age at the diagnosis. Second, the number of girls who participated in the study was low, which could have affected the results. The ratio of boys to girls is very high both for epidemiological and clinical samples. We recognize, therefore, that despite the low frequency of AS in girls versus boys, the results still beg the question as to whether this reflects a cultural gender bias in referral, as well as lesser degree of ADHD symptoms and oppositional and conduct behaviors observed among girls (Pliszka, 2010).

Finally, all our estimates on comorbidity are based on clinical cross-sectional analyses, and therefore, they do not reflect any representative population-based figures and ought to be interpreted with caution. These clinical comorbidity findings, nevertheless, are helpful in guiding treatment decisions and in increasing awareness among caregivers.

Footnotes

Declaration of conflicting interest

The authors declare that there is no conflict of interest.

Funding

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

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