Underestimation of autism spectrum disorders according to DSM-5 criteria: A pilot study

Introduction Recent studies on autism concern the number of individuals diagnosed with pervasive developmental disorder (PDD) according to DSM-IV-TR who may no longer qualify for diag- noses under the new DSM-5 autism spectrum disorder (ASD). ASD is diagnosed using the impairments in two dimensions: – the social and communication dimension; diagnosis of mental disorder in people with disorders of intellectual development (PWDID): An international study on clinical utility S.E. Cooray1,∗, Dr.R.Alexander(HonorarySeniorLecturer,ConsultantPsychiatrist)2, Professor G. Weber3, Professor S. Bhaumik4, Dr. A. Roy (Consultant Psychiatrist, Chair)5,6, Dr. M. Roy7, Dr. A. Bakheet (Consultant Psychiatrist)8, Dr. J. Devapriam9, J. Mendis10, Dr. A. Javed11 1 Royal College of Psychiatrists UK, Faculty of Psychiatry of Intellectual Disability, Radlett, United Kingdom 2 Department of Health Sciences, University of Leicester, Partnership in Care, Leicester, United Kingdom 3 University of Vienna, Faculty of Psychology, Department of Health, Development and Intervention, Vienna, Austria 4 Department of Health Sciences, University of Leicester, Leicestershire Partnership NHS Trust, Leicester, United Kingdom 5 Faculty of Psychiatry of Intellectual Disability, Royal College of Psychiatry, Coventry, United Kingdom 6 Warwickshire Partnership Trust, London, United Kingdom 7 Royal College of Psychiatrists, Faculty of Psychiatry of Intellectual Disability, London, United Kingdom 8 University of Khartoum, Department of Psychiatry, Khartoum, Sudan 9 Royal College of Psychiatrists UK, Faculty of Psychiatry of Intellectual Disability, Leicester, United Kingdom 10 National Institute of Mental Health Sri Lanka, Department of Psychiatry, Angoda, Colombo, Sri Lanka 11 Institute for Mental Health, Fountain House Institute for Mental Health, Lahore, Pakistan ∗ Corresponding author. Introduction Constituting 2% of the population, PWDID are a vulnerable group with a higher prevalence of mental disorders than the general population. ICD diagnostic criteria often rely on adequate cognitive functioning and hence diagnosis of mental dis- orders in PWDID can be difficult, consequently leading to inequity of treatment, prognosis and stigma. Our study critically analysed the available evidence base and explored the feasibility of applying modified diagnostic criteria within the context of cumulative iter- ative iteration. We present the outcome using diagnosis of DID and anxiety disorder as examples. Aims Address current shortcomings in ICD classification regarding PWDID by contributing effectively to the WHO ICD- 11 consultation process in collaboration with international stakeholders. Objectives Facilitate accessibility of ICD-11 criteria for diagnosis of mental disorders capable of engendering robust evidence based epidemiological data and healthcare in PWDID. Methods We evaluated current evidence via a systematic litera- ture search utilising PRISMA guidelines and developed pragmatic guidelines to adapt ICD diagnostic criteria in PWDID. A brief screener [Glasgow Level of Ability and Development Scale (GLADs)] for detecting DID was also studied internationally within the con- text of clinical utility (n = 136). Results The evidence base relating to mental disorders in PWDID is poor, significantly hampered by difficulties in applicability of diagnostic criteria. The GLADs appears to be a promising screening tool with good clinical utility for detecting disorders of intellectual development (DID) particularly where resources are scarce; the restricted and repetitive interests and behaviors (RRIB) dimension whereas PDD is diagnosed using impairments in three dimensions. All the studies indicate between 50 and 75% of individuals will maintain diagnoses. Objectives The aim of the study is to quantify how many individ- uals with previous PDD diagnoses under DSM-IV-TR criteria would maintain a diagnosis of ASD under DSM-5 criteria. Methods Our sample consists of 23 cases (21 males, 2 female) related to the treatment Centre “Una breccia nel muro” of Rome and Salerno. All the cases previous received a PDD diagnose accord- ing to DSM-IV TR criteria. The mean age of cases was 7.7 years. All the cases were diagnosed by our team according to DSM-5 crite- ria, clinicians also used to make diagnoses: the Autism Diagnostic Observation Schedule-2, the Autism Diagnostic Interview-Revised. Results Eighty-seven percent of cases with PDD were classified as ASD using DSM-5 criteria. Thirteen percent of cases, that previous received an Asperger diagnose, did not meet the ASD criteria (Fig. 1). Conclusions DSM-5 criteria may easily exclude cases with high functioning from ASD because they tend to be atypical for ASD according to this study.