First Impact Factor released in June 2010 and now listed in MEDLINE! Early Intervention in Psychiatry 2012; 6: 83–86
doi:10.1111/j.1751-7893.2011.00288.x
Brief Report Non-expert clinicians’ detection of autistic traits among attenders of a youth mental health service eip_288
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Richard Fraser,1 Sue Cotton,2 Ellen Gentle,2 Beth Angus,2 Kelly Allott2 and Andrew Thompson2 Abstract Aims: The aims of this study were to determine the point prevalence of autism spectrum disorders and to estimate the prevalence of autistic traits in a youth mental health service.
Results: Information on autism spectrum disorder status was obtained for 476 patients. Of the included patients, 3.4% (n = 16) had a confirmed diagnosis of autism spectrum disorder and 7.8% (n = 37) were reported by treating clinicians to exhibit autistic traits.
Corresponding author: Dr Richard Fraser, Sussex Early Intervention in Psychosis Service, New Park House, North Street, Horsham RH12 1RJ, UK. Email
[email protected]
Methods: Following three educational sessions on autism spectrum disorders, treating clinicians were interviewed to determine whether the clients on their caseloads had (i) a confirmed prior diagnosis of autism spectrum disorder; (ii) were felt to exhibit autistic traits; or (iii) were not felt to exhibit autistic traits.
Conclusions: The rate of autism spectrum disorder was higher in this population than that in community samples with twice as many again being identified as having autistic traits by their treating clinicians. This has implications for correct diagnosis and appropriate management in these settings.
Received 12 January 2011; accepted 10 July 2011
Key words: adolescent, autism spectrum disorders, co-morbidity, mental health, prevalence.
1
Sussex Early Intervention in Psychosis Service, Horsham, UK; and 2Orygen Youth Health and Orygen Youth Health Research Centre, Centre for Youth Mental Health, The University of Melbourne, Melbourne, Victoria, Australia
INTRODUCTION Autism spectrum disorders (ASDs), classified the as pervasive developmental disorders (PDDs) in International Classification of Diseases, 10th Revision (ICD-10) and Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), are complex developmental disorders that interfere with normal communication, social interaction or behaviour. ASDs include autistic disorder, Asperger disorder and PDD not otherwise specified (NOS). Prevalence estimates vary, but ASDs may affect as many as 1 per 100 children in general community samples.1,2 The prevalence of ASDs appears to have increased over recent years, the most likely explanation being a broadening of case definition and an improvement in recognition of these conditions.3 ASDs are associated with higher rates of co-morbid mental illness.4,5 Such co-morbidity has © 2011 Blackwell Publishing Asia Pty Ltd
the potential to significantly worsen an individual’s functioning, quality of life and negatively affect treatment outcomes. There are two major diagnostic and treatment issues pertaining to ASD and mental illness: (i) individuals with ASDs may present to services with mental health difficulties, but the developmental disorder has not been previously recognized; and (ii) the overlap of symptoms of ASD and other psychiatric illness makes diagnosis problematic and misdiagnosis common (see Fig. 1).6,7 Even though co-morbid mental illness is common in ASD, at present, very little is known about the prevalence of ASDs in either adult or youth mental health services.8,9 There have been no such reports to date in youth mental health services (for people aged 12–25 years), an area of specific service growth in psychiatry. 83
Autistic traits in a youth mental health service FIGURE 1. Diagnostic overlap in autism spectrum disorder (ASD) co-morbidity.
the lead author (RF). The core elements of this training were gaining an understanding of the ASDs as developmental disorders, recognition of autistic traits, differentiation of autistic traits from other psychiatric presentations and the kinds of psychiatric co-morbidities expected to occur with these conditions. Setting
The aim of this study was to describe the prevalence of confirmed ASD and suspected ASD traits in a specialized youth mental health service, Orygen Youth Health (OYH).
METHODS Design In November 2007, a cross-sectional audit of the point prevalence of ASDs in OYH was conducted over a 4-week period. All clients registered with the service at that time were included. There were no exclusions. Local ethics approval was obtained for this project. Treating clinicians were interviewed by three researchers (RF, AT, EG) over a 2-week period. They were presented with a prompt card detailing the DSM-IV PDD classification (autistic disorder, Asperger disorder and PPD NOS, but not including Rett’s disorder and childhood disintegrative disorder). They were then required to classify each of the clients on their caseload into one of the following three categories based on their knowledge of the client: (i) ASD diagnosis confirmed by a paediatrician, psychiatrist or clinical psychologist; (ii) suspected ASD traits; and (iii) ASD not suspected. Basic demographic information (gender, age and clinic in which they were treated) was also available on all clients. In addition to the written prompt, treating clinicians had received three separate, local professional development sessions on the diagnosis, treatment and co-morbidity of mental illness and ASD in the 2 months prior to the audit. This was provided by 84
OYH is a public mental health service providing psychiatric care for young people between the ages of 15 and 25 who live in the northwestern region of Melbourne, Australia. OYH has a catchment area with a population of about one million people from diverse sociocultural backgrounds. The service has between 500 and 600 registered clients at any time. There are several specialist clinics within OYH, including the Early Psychosis Prevention and Intervention Centre – an early psychosis service, Personal Assessment and Crisis Evaluation (‘ultra-high risk’ for developing psychosis clinic) and Youthscope (Youth Mood Clinic and HYPE clinic for emerging borderline personality disorder). The clinicians in the service are a mixture of psychiatrists, psychologists, nurses, social workers and occupational therapists. For more information on the Orygen service, see http://www.oyh.org.au. Data analysis Data analysis mainly involved the use of descriptive statistics. To determine the difference between those with and without a diagnosis of ASD in terms of demographic variables, chi-square analysis was used for categorical variables and analysis of variance was used for continuous variables. Alpha was set at 0.05 for all comparisons.
RESULTS There were 523 clients registered with OYH on the audit date, with information on ASD status being available for 476 patients (see Table 1 for demographic and diagnostic characteristics). Data on 47 cases were missing because of clinician unavailability for interview at the time of this study. Of the included patients, 3.4% (n = 16) had a confirmed diagnosis of ASD and 7.8% (n = 37) were reported by treating clinicians to have suspected ASD traits; 3.4% (n = 10) of those with psychotic disorders, and 4.1% (n = 5) of those with mood and anxiety disorders had a confirmed diagnosis of ASD. Suspected ASD trait rate was highest in the early psychosis © 2011 Blackwell Publishing Asia Pty Ltd
R. Fraser et al. TABLE 1. Demographic and diagnostic characteristics of those with confirmed ASD, Suspected ASD traits and no ASD
Gender male, % (n) Age (years), M (SD)† Diagnostic category‡ Psychosis, % (n) Ultra-high risk for psychosis, % (n) Mood and anxiety, % (n) Borderline personality disorder, % (n)
Confirmed ASD
Suspected ASD traits
No ASD
68.8 (11) 17.0 (2.0)
51.4 (19) 19.8 (3.4)
47.5 (201) 20.0 (3.0)
3.4 (10) 1.7 (1) 4.1 (5) 0
9.6 (28) 10.3 (6) 2.5 (3) 0
87.0 87.9 93.4 100.0
(254) (51) (114) (4)
†Age range 15–25 years. ‡Percentage of cases within diagnostic group who have a confirmed ASD, suspected ASD traits and no ASD. ASD, autism spectrum disorder; SD, standard deviation.
clinic (9.6%, n = 28). There were no statistically significant differences in prevalence rates among clinics. ASD status was unrelated to gender (c2 (2) = 2.91, P = 0.233). There was a significant difference between the three categories (confirmed ASD, suspected ASD traits and no ASD) with respect to age, (F(2,473) = 7.78, P < 0.001), with post hoc analyses (using Games–Howell test) revealing that those with a confirmed diagnosis of ASD were significantly younger, on average, than those with either suspected ASD traits (P = 0.002) or no ASD (P < 0.001). Reporting of autistic traits and possible ASDs was evenly spread across the clinics, except for the HYPE clinic where there were none reported.
DISCUSSION The major finding of this study was the increased rate of those with confirmed prior diagnosis of ASD (3.4%) in a youth clinic sample when compared with community settings (1%).2 Indeed, it might be expected that the rate of ASD in a psychiatric setting would be higher than that in the community as people with ASD are known to have increased rates of mental health problems.10 There was no difference in gender with respect to ASD diagnosis, which is perhaps unexpected given that the reported maleto-female ratio is 4:1 in the general community.11 Interestingly, those with a prior diagnosis of ASD were significantly younger in the clinic sample. It is possible that this group may be more vulnerable to early-onset mental illness and, hence, more impaired at an earlier age, with correspondingly more complex needs. This would need further investigation. It is generally accepted that people more profoundly affected by ASDs tend to be diagnosed at an earlier age;12 however, those with higher function© 2011 Blackwell Publishing Asia Pty Ltd
ing, or Asperger-type presentations, may not be identified until later on when they present to services with psychiatric disorder. This is consistent with Mouridsen et al.’s follow-up study of 89 children with PDD NOS in which 70% developed a co-morbid psychiatric disorder in adulthood, the most common being schizophrenia, compared with 11% of controls.13 The results suggest that following specific education and an increased awareness of ASD, the clinical staff were able to identify significant numbers of young people with autistic traits who may have an ASD but had not been formally assessed (7.8%). Limitations The results from this study may represent an overestimate of ASD prevalence. Although those with established ASD were not assessed by our research team because diagnoses were made by specialists and recorded in reports or clinic letters, they are likely to be robust. The data were collected via treating clinicians and not from individual client assessment. As this was an audit of a whole service, it was felt acceptable to interview treating clinicians rather than the individual patients or their carers. Such a methodology was successfully used in previous studies.8,9 It was not mandatory for treating clinicians to attend the professional development sessions. Although not formally recorded, attendance was felt to be satisfactory across the service. The interrater reliability of the data collection tool was not measured. The interview tool was a simple three-item response with written DSM-IV-derived prompts. Influence from the rater was minimal and therefore not likely to be subject to substantial rater bias. Data were not collected regarding prevalence of intellectual disability (ID). Although ASDs are strongly associated with ID,14 Orygen is not resourced to provide a service for young 85
Autistic traits in a youth mental health service people with moderate or severe ID. It would, however, be interesting in the future to explore possible associations between ASD, IQ and age of onset of psychiatric disorder. CONCLUSIONS The rate of confirmed ASDs in a youth mental health service is higher than that in community settings. There are a number of other young people with autistic traits and possible undiagnosed ASD. The presence of an ASD together with a mental illness complicates not only diagnosis but also the management of both disorders. There already exists an evidence base to support treatment of autismspecific behaviours.15,16 There are, however, limited guidelines and few empirical studies regarding the treatment of co-morbidity in ASD, particularly psychosis. This study highlights the need to develop such guidelines, as although relatively uncommon in community settings, the co-occurrence of ASD and psychiatric illness, especially psychosis, is sufficiently common in specialist settings, such as OYH, to warrant specific attention. REFERENCES 1. Schechter R. Continuing increases in autism. Arch Gen Psychiatry 2008; 65: 19–24. 2. Baird G, Simonoff E, Pickles A, Chandler S, Meldrum D, Charman T. Prevalence of disorders of the autism spectrum in a population cohort of children in South Thames: the Special Needs and Autism Project (SNAP). Lancet 2006; 368: 210–15.
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3. Fombonne E. Epidemiology of pervasive developmental disorders. Pediatr Res 2009; 65: 591–8. 4. Matson JL, Nebel-Schwalm MS. Comorbid psychopathology with autism spectrum disorder in children: an overview. Res Dev Disabil 2007; 28: 341–52. 5. Skoukauskas N, Gallagher L. Psychosis, affective disorders and anxiety in autism spectrum disorder: prevalence and nosological considerations. Psychopathology 2010; 43: 8–16. 6. Mouridsen SE. Psychiatric disorders in individuals diagnosed with infantile autism as children: a case control study. J Psychiatr Pract 2008; 14: 5–12. 7. Dossetor DR. ‘All that glitters is not gold’: misdiagnosis of psychosis in pervasive developmental disorders – a case series. Clin Child Psychol Psychiatry 2007; 12: 537–48. 8. Chang H-L. Screening for autism spectrum disorder in adult psychiatric outpatients in a clinic in Taiwan. Gen Hosp Psychiatry 2003; 25: 284–8. 9. Nylander L, Gillberg C. Screening for ASDs in adult psychiatric out-patients: a preliminary report. Acta Psychiatr Scand 2001; 103: 428–34. 10. Ghaziuddin M, Zafar S. Psychiatric comorbidity of adults with autism spectrum disorders. Clin Neuropsychiatry 2008; 5: 9–12. 11. Fombonne E. Epidemiology of autistic disorder and other pervasive developmental disorders. J Clin Psychiatry 2005; 66 (Suppl. 10): 3–8. 12. Mandell D, Novak M, Zubritsky C. Factors associated with age of diagnosis among children with autism spectrum disorders. Pediatrics 2005; 116: 1480–6. 13. Mouridsen SE, Rich B, Isager T. Psychiatric disorders in adults diagnosed with atypical autism. A case control study. J Neural Transm 2008; 115: 135–8. 14. Hoekstra RA, Happé F, Baron-Cohen S, Ronald A. Association between extreme autistic traits and intellectual disability: insights from a general population twin study. Br J Psychiatry 2009; 195: 531–6. 15. Kolevzon A, Mathewson KA, Hollander E. Selective serotonin reuptake inhibitors in autism: a review of efficacy and tolerability. J Clin Psychiatry 2006; 67: 407–14. 16. Rossignol DA. Novel and emerging treatments for autism spectrum disorders: a systematic review. Ann Clin Psychiatry 2009; 21: 213–36.
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