Cognitive Impairment and Formal Thought Disorders in Parents of Early-Onset Schizophrenia Patients

Abstract

Background: Both cognitive impairment and formal thought disorder (communication disturbances) found in patients with schizophrenia are also commonly observed in their relatives. Recently, the role of such deficits as putative endophenotypes of schizophrenia has been proposed. However, in a majority of studies, the families of adult patients were assessed whereas the relatives of early-onset psychotic subjects were rarely studied. The aim of our study was to evaluate the presence of cognitive impairment and formal thought disorders in parents of adolescents with a diagnosis of schizophrenia spectrum disorder (SSD) and in matched healthy controls. Method: Thirty-eight parents of 29 SSD adolescents and 38 healthy controls were assessed with a battery of neurocognitive tests and the Thought, Language and Communication Scale. Results: Parents of schizophrenia patients showed an increased tendency for perseverative thinking when compared to matched healthy controls. No statistically significant differences in cognitive functioning were observed between the groups. Conclusion: These results may suggest the need for further exploration of communication disturbances as a potential endophenotypic marker of early-onset schizophrenia.

Unaffected first-degree relatives of essential tremor cases have more imbalance than age-matched control subjects

“…As such, endophenotypes have been identified for a wide range of neurological disorders. In psychiatry as well, endophenotypic manifestations have been well-described [8].…”

“…In addition to furthering genetic analysis, endophenotypes can clarify diagnosis and foster the development of animal models [4]. In movement disorders research, endophenotypes have been studied the most in patients and families with dystonia [5] but they have also been studied in patients with Tourette syndrome [6] and more broadly in other neurological [7] and psychiatric [8] illnesses.…”

The clinical relevance of formal thought disorder in the early stages of psychosis: results from the PRONIA study

“…However, this traditional approach may not fully capture the clinical heterogeneity of psychosis in terms of both disease course and severity [21,24,27,42]. FTD may represent a clinical fingerprint of disease severity [42] as it encompasses observable speech-related, and cognitive impairments of psychosis. As findings from a recent systematic review indicated, FTD-especially disorganization-might have early diagnostic and prognostic relevance in the early stages of psychosis [39].…”

“…Psychotic disorders are closely linked with neurocognitive and functional impairments [ 17 , 49 ] that frequently precede disease onset and persist after remission of the acute illness [ 22 , 37 ]. Formal thought disorder (FTD) is a multifaceted construct of disturbances in thought, communication and language, such as loosening of associations, blocking, semantic and phonemic paraphasia [ 28 , 42 ]. Previous literature revealed that FTD is not only a core feature of psychosis but that it is also associated with adverse social and functional outcomes in psychotic patients [ 3 , 21 , 25 , 27 , 28 ].…”

“…In summary, these findings may point towards FTD playing an important role in explaining the behavioural, psychopathological and functional heterogeneity of disease manifestations in both early and prodromal phases of psychosis. So far, this aspect has remained under-investigated, [ 42 , 43 ] as research on clinical markers of psychosis has focused rather on positive and negative symptoms as well as on cognitive phenotypes of the disorders [ 44 ]. However, this traditional approach may not fully capture the clinical heterogeneity of psychosis in terms of both disease course and severity [ 21 , 24 , 27 , 42 ].…”