Systematic Review of the Clinical Presentation of Schizophrenia in Intellectual Disability

Perceptions of learning disability nurses and support staff towards people with a diagnosis of schizophrenia

WHAT IS KNOWN ABOUT THE SUBJECT?: People with learning disability are more likely than the general population to develop schizophrenia. Personal recovery philosophies are based on positive attitudes and an optimism that recognizes and values people and their strengths and capacity to achieve goals. Little is known from previous studies about the illness perceptions of learning disability practitioners who work with people that experience both a learning disability and schizophrenia. The illness beliefs of learning disability practitioners about schizophrenia may mediate the potential for social exclusion and limit recovery outcomes. WHAT THIS STUDY/PAPER ADDS TO EXISTING KNOWLEDGE?: The findings show that the illness beliefs of learning disability practitioners and support workers regarding schizophrenia are pessimistic in terms of the consequences for people with schizophrenia and learning disability and their relatives as well as the chronic course of the illness. WHAT ARE THE IMPLICATIONS FOR CLINICAL PRACTICE?: This study identifies the nature of LD practitioner perceptions about schizophrenia and provides guidance about how personal recovery philosophies can be applied to the management of LD and schizophrenia. The beliefs of learning disability practitioners and support workers regarding schizophrenia need to be reframed to support better recovery outcomes and social inclusion for this group. The findings from this study can inform the development of training in bio-psycho-social models of schizophrenia, recovery approaches, family/carer interventions, clinical supervision, mentorship and reflection on clinical practice, which could be potentially useful strategies to help facilitate a reframing of beliefs.

ABSTRACT

Background and purpose of study The prevalence of schizophrenia in people with learning disability is 3-4%. This is the first study to investigate the illness perceptions of learning disability (LD) practitioners towards people with schizophrenia. Methods Learning disability practitioners (n = 210) that work with people with LD and schizophrenia completed a modified version of the Illness Perception Questionnaire Schizophrenia Carers Version (IPQ-SCV). Descriptive and correlational analyses were conducted for all of the IPQ-SCV subscales. Results A significant positive correlation was found between consequences relative and consequences patient (0.495, P < 0.001), and a negative correlation was found between timeline episodic and timeline chronic (-0.243, P < 0.001) subscales. Discussion Consistent with previous evidence found regarding negative staff attitudes to schizophrenia recovery outcomes, course and chronicity, the current investigation has extended and confirmed these observations to staff working with individuals with comorbid schizophrenia and learning disability. Implications for practice This study identifies the nature of LD practitioner perceptions about schizophrenia and contributes to the development of the recovery philosophy in relation to the management of LD and schizophrenia. The findings inform the design of training modules in bio-psycho-social models of schizophrenia, recovery approaches, family intervention, clinical supervision and reflection. These can help LD practitioners to reframe their schizophrenia/LD illness beliefs.

Towards diagnostic markers for the psychoses

Psychotic disorders are currently grouped under broad phenomenological diagnostic rubrics. Researchers hope that progress in identifying aetiological mechanisms will ultimately enable more precise division of heterogeneous diagnoses into specific and valid subgroups. This goal has been an aim of psychiatry since the 19th century, when patients with general paresis were thought to have "insanity" similar to dementia praecox and manic depressive illness. Nowadays, the constructs of organic-induced and substance-induced psychotic disorder show that our diagnostic classification system already reflects, in part, aetiological factors. Most recently, gene copy number variation and autoimmunity have been associated with schizophrenia. We suggest how, on the basis of recent scientific advances, we can progress the identification of further putative subgroups and make the most of currently available interventions. Prompt diagnosis and treatment, and a more routine search for causes, could preserve function and improve outcome, and therefore be more acceptable to patients and carers.

Association of schizophrenia spectrum and autism spectrum disorder (ASD) symptoms in children with ASD and clinic controls

OBJECTIVE

This study examines relations between the severity of specific symptoms of schizophrenia spectrum disorder (SSD) and severity of the three defining symptom domains of autism spectrum disorder (ASD) in children with ASD (N=147) and child psychiatry outpatient referrals (Controls; N=339).

METHOD

Participants were subdivided into four groups depending on ASD status (±) and whether they met symptom criteria for attention-deficit/hyperactivity disorder (±ADHD). Their mothers and teachers evaluated them with a DSM-IV-referenced rating scale.

RESULTS

Correlations between schizoid personality symptoms and ASD social skills deficits were moderate to large, and this was true for children with ASD and Controls, regardless of ADHD status, and for mother's and teachers' ratings. Conversely, severity of hallucinations, delusions, and disorganized thinking were minimally correlated with ASD severity with the exception of Controls with ADHD. The disorganized behavior and negative symptoms of schizophrenia evidenced the strongest pattern of associations with ASD symptoms, and this was particularly true for children with co-morbid ADHD (±ASD, all three ASD symptom dimensions), and for teachers' ratings of all four groups. Nevertheless, there was considerable variability in relations for specific symptoms across informants and groups. Correlations between SSD symptom severity and IQ were generally low, particularly among the ASD Only group and for all teacher-rated symptoms.

CONCLUSION

Associations between ASD and SSD symptoms were often dimension-specific, and this was particularly evident in children without ADHD (±ASD; mothers' ratings). Findings were interpreted as supporting the deconstruction of complex clinical phenotypes as a means of better understanding interrelations among psychiatric syndromes.

Association testing of copy number variants in schizophrenia and autism spectrum disorders

BACKGROUND

Autism spectrum disorders and schizophrenia have been associated with an overlapping set of copy number variant loci, but the nature and degree of overlap in copy number variants (deletions compared to duplications) between these two disorders remains unclear.

METHODS

We systematically evaluated three lines of evidence: (1) the statistical bases for associations of autism spectrum disorders and schizophrenia with a set of the primary CNVs thus far investigated, from previous studies; (2) data from case series studies on the occurrence of these CNVs in autism spectrum disorders, especially among children, and (3) data on the extent to which the CNVs were associated with intellectual disability and developmental, speech, or language delays. We also conducted new analyses of existing data on these CNVs in autism by pooling data from seven case control studies.

RESULTS

Four of the CNVs considered, dup 1q21.1, dup 15q11-q13, del 16p11.2, and dup 22q11.21, showed clear statistical evidence as autism risk factors, whereas eight CNVs, del 1q21.1, del 3q29, del 15q11.2, del 15q13.3, dup 16p11.2, dup 16p13.1, del 17p12, and del 22q11.21, were strongly statistically supported as risk factors for schizophrenia. Three of the CNVs, dup 1q21.1, dup 16p11.2, and dup 16p13.1, exhibited statistical support as risk factors for both autism and schizophrenia, although for each of these CNVs statistical significance was nominal for tests involving one of the two disorders. For the CNVs that were statistically associated with schizophrenia but were not statistically associated with autism, a notable number of children with the CNVs have been diagnosed with autism or ASD; children with these CNVs also demonstrate a high incidence of intellectual disability and developmental, speech, or language delays.

CONCLUSIONS

These findings suggest that although CNV loci notably overlap between autism and schizophrenia, the degree of strongly statistically supported overlap in specific CNVs at these loci remains limited. These analyses also suggest that relatively severe premorbidity to CNV-associated schizophrenia in children may sometimes be diagnosed as autism spectrum disorder.