Schizophrenia in autistic people with intellectual disabilities: Symptom manifestations and identification
Trine Lise Bakken, Arvid Nikolai Kildahl, Linn Beate Ludvigsen, Tale Gjertine Bjørgen, Caroline Dalhaug, Jane Margrete Askeland Hellerud, Oddbjørn Hove, Ann Magritt Solheim‐Inderberg, Kjersti Karlsen, Sissel Berge Helverschou
Abstract
BACKGROUND: The assessment of schizophrenia in autistic people with intellectual disabilities is challenging. This study aimed to explore the identification of schizophrenia in this population. METHODS: Using data from a clinical multi-centre study, reported symptoms in 26 autistic individuals with intellectual disabilities diagnosed with co-occurring schizophrenia were explored. Scores on two checklists (Psychopathology in Autism Checklist [PAC], Aberrant Behaviour Checklist [ABC]) were compared with two comparison groups: autistic individuals with intellectual disabilities and other mental disorders (94), or no mental disorder (63). RESULTS: Reported symptoms of schizophrenia in this population met the formal diagnostic criteria. For PAC/ABC scales, only PAC psychosis differed for the schizophrenia group. Among participants with schizophrenia, two were diagnosed with additional mental disorders. Elevated scores for anxiety and depression were common. CONCLUSIONS: Emphasising core symptoms seems necessary when assessing co-occurring schizophrenia in autistic people with intellectual disabilities. The PAC may serve as a helpful screening tool.