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Viewpoint Indian Pediatrics 2001; 38: 384-390 |
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Clinical and Neurodevelopmental Profile of Young Children with Autism |
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Autism is a neurodevelopmental disorder characterized by deficits in social interaction, abnormal language and imaginative play, a restricted repertoire of activities and interests. It has an onset prior to age of 3 years(1-3). The Western prevalence estimates range from 3 to 16 per 10,000(4,5) and there is some evidence to indicate that the incidence may be rising(6). The criteria for diagnosing autism are entirely clinical. Semi-structured interview schedules(7,8) and rating scales(9,10) have been developed to assist the clinician in increasing the objectivity and reliability of assessment. The DSM IV classifies autistic disorder among the pervasive developmental disorders (PDD)(11). The term PDD sets apart autism and similar conditions from mental deficiency, developmental language disorders, on the one hand, and schizophrenia on the other. Early recognition of children with autism is of crucial importance as early intervention programs have shown significant improve-ments in cognitive and behavioral functioning of autistic children(12). It is generally felt that autism is rarely seen in India(13). Our experience suggests that there is a lack of awareness about the condition among pediatricians and often these children are misdiagnosed and clubbed under the general category of mental retardation and/or speech and language disorders. Very little, if any, systematic data are available from India and other developing countries. We conducted this study with the aim of describing and analyzing the clinical and developmental profile of Indian children with autism.
Children below 5 years of age in whom we made a diagnosis of autism between November, 1997 to June, 1999 constituted the subjects of this study. We included only those children with a primary diagnosis of autism with no other recognizable neurological condition wherein autism could be an associated feature. This was done to obviate the confounding effects of the neurological disorder on the neurodevelopmental profile of the children. We excluded one child with tuberous sclerosis on this basis. There were 16 children (9 boys, 7 girls) and the sex ratio was 1.3 : 1. The mean age at referral was 42.8 months (range 34 to 56 months). None of these children has been diagnosed to have autism and had been referred for either speech delay (n = 10) or developmental delay (n = 6). A detailed history including details of prenatal and perinatal events, and develop-mental milestones was taken. Complete physical and neurological examination and neurodevelopmental assessment was done in all the children. Hearing and visual defects, other neurological deficits and disorders were excluded. Diagnosis of Autism The diagnosis of autism was made independently by the two authors based on the criteria delineated by the DSM IV which assesses three broad behavioral domains: social interaction, communication, and activities and interests. In addition, the Childhood Autism Rating Scale (CARS) was administered to all children(10). The CARS is a 15 item observational rating scale which elicits information on the child’s behavior with respect to relating to people, imitation, body use, adaptation to change, intellectual response, etc. Each item is scored on a continuum from normal, scored as 1, to severely abnormal and/or inappropriate, scored as 4. Scores for all the 15 items are summed to yield a total score that ranges from 15 to 60. The cut off score for a diagnosis of autism is 30. Scores from 30 to 37 are categorized as mildly-moderately autistic and scores above 37 are categorized as severely autistic(10). Developmental Assessment A detailed developmental assessment was done using: (i) the Developmental Profile II (DP II) which assesses the child’s develop-mental status from birth through 9 ½ years(14). It is an 186 items inventory which assesses a child’s functional developmental age in five domains: physical, social, self help, academic and communication. The functioning of the child is expressed in developmental ages in months and the academic age of the child can be converted to an IQ equivalency score (IQE); (ii) The Vineland Social Maturity Scale (VSMS, Indian adaptation) is designed to assess the child’s development level in looking after his practical needs and taking responsibility in daily living(15). The scale yields a social age which can be converted to a Social Quotient (SQ).
There was an excellent concordance of diagnosis between the two clinicians. All children had CARS scores in the autistic range. The mean CARS score for the sample was 38.5 (range 30.5 to 50) with 62.5% of the children scoring in the severely autistic range. A history of antenatal problems was present in 5 cases (31.3%). Twelve (75%) were normal deliveries, 3 (18.8%) were Caesarian and 1 (6.5%) was breech. Perinatal problems were reported in 4 cases (25%). The physical examination of all the children was essentially normal. Fifteen children had a normal head circumference. One child had a head circumference <2 SD of normal. None of the other children had any other recognizable neurologic problem. The M : F ratio was 1.3 : 1 which was much lower than reported in the literature. However, it may be noted that among those autistic children with severe mental retardation, like our sample, the male excess is less pronounced(2). The percentage of children showing each behavioral characteristic is presented in Table I. Seven characteristics were endorsed by at least 50% of the autistic children. Regarding the social domain, majority of the children had impairment in the use of non verbal behavior (93.8%) and lack of social and/or emotional reciprocity (93.8%). Seventy five per cent of the children demonstrated impaired peer relationship, while abnormal seeking of comfort was reported in only 37.5% of the children. In the communication domain, it is important to note that the majority (81.3%) had no mode of communication. Absence of imaginative play was reported for all the subjects. Eighty one per cent of the children were essentially having no mode of communication (non-verbal group) and had an expressive vocabulary of less than 10 words and understood very little of the language. Among the 3 children who were verbal, all had abnormal speech content and two had impaired ability to initiate conversation. Interestingly, two out of three verbal children repeated parts of memorized TV commercials. Moreover, non-communicative echolalia was particularly marked in the speech of the three verbal autistic children. Pronominal reversal, i.e., child referring to himself as "you" or by name rather than "I" or "me" was reported in two of the three verbal children.
The "activities and interests" domain revealed a restricted range of interests in 81.3% of the children. Peculiar preference for lining or stacking up of objects, or playing with a single toy repeatedly was seen. One child preferred to constantly rotate the cycle wheel. Many children (62.5%) displayed repetitive stereotyped motor movements including twirling, jumping, flapping of hands, hand gazing, mouthing and tip toe walking. However, insistence on routines was endorsed for fewer than 13% of the children. It is noteworthy that 25% of the parents reported that the early development of their children was normal and at around 18 to 24 months of age their children underwent a behavioral regression in the language area. In none of the children was this regression associated with regression of motor milestones, seizures or any other physical illness. Developmental testing revealed that majority of the children were delayed in all the 5 developmental domains. The most affected were the communication (M = 15.6 months), social (M = 15.8 months) and academic (M = 15.6 months) sectors which were more than ten months lower than the physical (M = 25.5 months) and self help (M = 24.4 months) sectors. Most (87.5%) of the autistic children had skills fairly evenly retarded across all areas of functioning but two children had markedly superior rote visual memory and could identify several advertised products and their pictures with ease. The mean Social Quotient as measured by the VSMS was 57.3 (range 24 to 87) and the IQ equivalency score computed from the Academic subscale of the DP II was 37.3 (range 6 to 78). An overwhelming majority (93.8%) of the autistic children had IQs in the mentally retarded range (moderate retardation = 43.8%, severe retardation = 50%) and only 1 child had an IQ in the borderline range.
Our study reveals that autism is not an uncommon condition in India. Although, ours is a tertiary hospital and these figures do not reflect prevalence in general population, the fact that all of these children were referred with diagnoses other than autism reflects the lack of awareness of the problem among pediatricians in our country. Six characteristics were observed and reported for the majority of the children diagnosed with autism. These characteristics were impairment in use of non-verbal behavior, absence of imaginative play, lack of social and emotional reciprocity, restricted range of interests, no mode or delay in communication and impaired peer relation-ship. These results suggest that deficits in social interaction, play and communication may be more prominent in autistic children less than 4½ years of age. This pattern is consistent with Lorna Wing’s description of the autistic spectrum of disorders having in common a triad of impairments in social interaction, communication, and narrow and repetitive patterns of behavior(3). It is noteworthy that deviant pattern of reciprocal gaze and eye contact was the most striking manifestation and was seen in almost all the autistic children. Although, patterns of gaze avoidance in autism have been found to change over the course of development, even the highest functioning autistic individuals have been observed to show gaze avoidance and/or failure to use eye contact in the regulation of social interaction(16). In contrast, five characteristics were endorsed rarely by the parents (fewer than 38%). These characteristics included insist-ence on routines, impairment in ability to initiate conversation, stereotyped repetitive use of language, abnormal seeking of comfort and preoccupation with parts of objects. Since 81% children were mute or spoke only a few words with meaning, it is not surprising that the other two diagnostic criteria related to speech, i.e., impairment in ability to initiate conversation and stereotyped repetitive use of language were endorsed rarely. It seems therefore that impairment in speech and conversational skills may not be the defining features of younger autistic children. The failure to obtain evidence on a need for routines is consistent with other research studies with young autistic children(17). Studies suggest that behavior indicative of a need for routines may emerge later in the developmental course of autism and may be more obvious in autistic children older than 5 years of age(18). Most of the autistic children in our study were found to be securely attached to the parents and/or grand parents and used their parents as a source of comfort. Indifference to caregivers did not emerge as an important feature of autism in young children(17). The finding that the early development of 25% of the autistic children was normal is similar to that reported in the literature(1). With respect to adaptive behavior functioning as measured by the DP II, the autistic children demonstrated significantly weaker socializa-tion and communication skills relative to their motor and self help skills. There was a difference of at least 10 developmental months between these domains. These results are not surprising since communication and social deficits are central to the diagnosis of autism. These results suggest that autistic children typically show a more uneven pattern of skill development across different adaptive beha-vior domains. Moreover, parental reports on child’s adaptive behavior functioning can help in the diagnosis of autism. Deficits in adaptive social behavior in children with autism have been previously documented(19). Previous research has recorded that 60% to 70% of children with autistic disorder have intellectual abilities that fall within the range of mental retardation, 20% to 35% have borderline to normal IQ scores (70 to 100) and less than 5% have IQ scores over 100(20). The present results, however, reveal that an overwhelming majority of the autistic children had intellectual abilities within the mental retardation range. It is therefore likely that the parents of autistic children with mental retardation would seek professional help at an earlier age than parents of autistic children with normal intelligence. In conclusion, our results suggest that in order to facilitate early detection of children with autism, six behavioral characteristics including impairment in use of non-verbal behavior, impaired peer relationships, lack of social and emotional reciprocity, no mode of communication, absence of imaginative play and restricted range of interests warrant more consideration than other behavioral character-istics. In contrast, other behavioral features including abnormal seeking of comfort, impairment of ability to initiate conversation, stereotyped repetitive use of language and insistence on routines are less likely to be seen in autistic children younger than five years. Therefore, the absence of these other behavioral characteristics should not be a reason for the primary care physicians to rule out a possible diagnosis of autism. It is concluded that early diagnosis and parti-cipation in early intervention programs would go a long way in reducing impairment and help in the acquisition of skills. Contributors: PS co-ordinated the study and drafted the paper and will act as the guaranter for the paper. PM collected the data, helped in designing the study and drafting of the paper. Funding: None.
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