Autism in adult psychiatry outpatients - prevalence, comorbidity, suicidality and cognition
Abstract
Background: Autism Spectrum Disorder (ASD), one of the Early Symptomatic Syndromes Eliciting Neurodevelopmental Clinical Examinations (ESSENCE), is a neurodevelopmental disorder (NDD) characterised by a pattern of deficits in reciprocal social communication and social interaction, and restricted and/or repetitive behaviours (including sensory abnormalities). Under its current DSM-5 definition, ASD occurs worldwide in 1-1.5% of the general population but is more prevalent in clinical populations. The prevalence of ASD in adult psychiatric outpatient services is not known, and adult psychiatric outpatients with ASD are often not examined “holistically”.
Aims: Examine prevalence of ASD in adult outpatient psychiatry, psychiatric, cognitive and sociodemographic profiles, functional level, suicidality and non-suicidal self-injury (NSSI).
Methods: Studies I, II and III examined newly referred psychiatric outpatients (N = 90) at a psychiatric outpatient clinic in Helsingborg, Sweden during 2019 and 2020. Patients were screened with the Ritvo Autism Asperger Diagnostic Scale – Revised (RAADS-R) or the abbreviated RAADS-14 Screen, and patients with screening results indicating possible ASD were offered to participate in in-depth clinical assessments by experienced clinicians using well-validated psychometric instruments. In Study IV neuropsychological test results were analysed in outpatients (N = 30) who had received clinical diagnoses of ASD at an NDD assessment unit.
Results: ASD was diagnosed in 18.9% of newly referred outpatients, with an additional 5.7% showing “subthreshold” symptoms of ASD. Participants with ASD had more psychiatric comorbidity, more NDDs, more anxiety disorders and lower functional level compared to participants without ASD. No differences were found between participants with and without ASD in sociodemographic characteristics. Suicidal thoughts and behaviour, and NSSI, were common among participants with ASD; similar to what has previously been reported among psychiatric outpatients. Substantial deficits in functional level were found, regardless of Intelligence Quotient (IQ) level. Working memory and processing speed explained more than one fifth of the variance in functional level.
Conclusions: In summary, the results of this thesis suggest that adult psychiatric services need a substantial increase in knowledge about ASD, and to adjust and adapt protocols and routines to become more “autism-friendly”.
Parts of work
1. Nyrenius, J., Eberhard, J., Ghaziuddin, M., Gillberg, C., & Billstedt, E. (2022). Prevalence of autism spectrum disorders in adult outpatient psychiatry. Journal of Autism and Developmental Disorders, 52(9), 3769-3779. https://doi.org/10.1007/s10803-021-05411-z 2. Nyrenius, J., Eberhard, J., Ghaziuddin, M., Gillberg, C., & Billstedt, E. (in press). The "lost generation" in adult psychiatry: psychiatric, neurodevelopmental and sociodemographic characteristics of psychiatric patients with autism unrecognized in childhood. The British Journal of Psychiatry Open. 3. Nyrenius, J., Waern, M., Eberhard, J., Ghaziuddin, M., Gillberg, C., & Billstedt, E. (2023). Autism in adult psychiatric outpatients: self-reported suicidal ideation, suicide attempts, and non-suicidal self-injury. Manuscript submitted for publication. 4. Nyrenius, J., & Billstedt, E. (2020). The functional impact of cognition in adults with autism spectrum disorders. Nordic Journal of Psychiatry, 74(3), 220-225. https://doi.org/10.1080/08039488.2019.1694698
Degree
Doctor of Philosophy (Medicine)
University
University of Gothenburg. Sahlgrenska Academy
Institution
Institute of Neuroscience and Physiology. Department of Psychiatry and Neurochemistry
Disputation
Fredagen den 12 maj 2023, kl 13.00, Hörsal Arvid Carlsson, Academicum, Medicinaregatan 3, Göteborg
https://gu-se.zoom.us/j/64522765525?pwd=aWh1dGZPVnRaWjViZDZVcTRwVnN1dz09
Date of defence
2023-05-12
johan.nyrenius@gu.se
Date
2023-04-12Author
Nyrenius, Johan
Keywords
Autism
Adults
Psychiatry
Suicidality
Non-Suicidal self-injury
Cognition
Outcomes
Publication type
Doctoral thesis
ISBN
978-91-8069-169-7 (PRINT)
978-91-8069-170-3 (PDF)
Language
eng