Some clinical examples illustrating some of the issues in the assessment of people with intellectual disability and psychosis. 1. A woman was referred to dual disability services for review by acute psychiatric services as a recent IQ placed her in the mild intellectual disability range. At assessment interview revealed that she attended a normal school and worked in full time employment prior to the onset of her recurrent psychotic illness. IQ assessment was undertaken when she was acutely unwell and is unlikely to have been accurate. In addition there were significant negative symptoms which impacted on her adaptive functioning. The diagnosis was schizophrenia with significant psychiatric disability but no intellectual disability and she did not require specific disability services. 2. A man with moderate intellectual disability was assessed because he was accusing his family of stealing from him and his carers thought he was paranoid. He was seen by a GP who noted that his thinking seemed very disjointed as though he had thought disorder (one of the symptoms of schizophrenia). On assessment his communication abilities were investigated and he was found to have significant deficits in expressive language, but there was no evidence that his speech or thoughts were more disorganised than usual. The apparent thought disorder resulted from the specific communication disorder and was not to be considered to be psychotic in origin. Unfortunately on investigation his beliefs about his family stealing from him and calling him names turned out to be true and they were not psychotic symptoms. 3. A woman with autism and psychosis was referred for review. She had been talking to herself whenever she was not involved in activities and the nature of her self-talk was repetitive and odd.  It was thought that her self-talk was because she was responding to hallucinations. However, assessment uncovered that the self-talk began in childhood and is repetitive and odd because she was repeating word for word the scripts of her favourite programmes. This is not uncommon in people with autism and it was not casuing any problems. Treatment for psychosis was not indicated. 4. A young man with moderate intellectual disability and autistic traits presented with frequent discussion of past and recent abuse. He was known to have experienced neglect and physical abuse in adolescence and so the repeated reports of abuse were viewed as normal and the frequency of their repetition was attributed to his autism. However he became increasingly distressed by the abuse and was convinced that people were coming into his room at night and interfering with him. It was apparent that the current accusations of assault could not have been true and a psychotic illness was diagnosed. Following effective treatment all discussion of abuse stopped. 5. A young woman with moderate intellectual disability who started pushing a pram around with a baby doll in it was thought to be pretending that she was a mother. This was considered to be normal fantasy play for her level of function. Psychiatric assessment and observation of her behaviour identified additional symptoms of paranoid beliefs that her flat mate was trying to harm her in connection with Hitler; the kitchen were trying to poison her by giving her out of date food and her house supervisor was stealing her money so that she would start shop lifting which would lead to prostitution. It  also became apparent that she was hearing the doll talk to her making her believe this was a real baby and that she was a mother. With this information the behaviour was identified as being secondary to a psychotic illness rather than fantasy and treatment was commenced.   

Case Studies