Cognitive deficits in clinical and familial high risk groups for psychosis are common as in first episode schizophrenia.

The aim of this study is to compare the neurocognitive functions in individuals with clinical or genetic risk for psychosis, in patients with first-episode schizophrenia (FES) and in healthy controls. We compared cognitive functions of 52 individuals at ultra high risk (UHR) for psychosis, 53 patients with FES, their 30 healthy siblings (familial high risk group, FHR) and controls. FES group had worse neuropsychological performance than controls in all of the domains. UHR group had worse performance in verbal learning, attention, and working memory than controls. Additionally, individuals at UHR with familial risk had worse performance on executive functions than the control group. FES group had lower global composite score than UHR group, and worse sustained attention than FHR group. FHR group had worse performance on executive functions and attention than controls. We found no difference in cognitive performances of UHR and FHR groups. Cognitive deficits in UHR and FHR groups were largely similar to those with FES. These findings support that cognitive deficits may arise before the first episode of schizophrenia.

The history of childhood trauma among individuals with ultra high risk for psychosis is as common as among patients with first-episode schizophrenia.

AIM: Childhood trauma (CT) is more common in patients with psychosis than in general population and is found to be related to the severity of symptoms. The objective of this study was to investigate the severity of CT, and its relationship with clinical features in two different groups: first-episode schizophrenia (FES) and ultra high risk for psychosis (UHR) groups. METHODS: In this cross-sectional study, 83 patients with FES, 41 individuals with UHR and 69 healthy controls were included. Clinical features were evaluated with the Brief Psychiatric Rating Scale, the Scale for the Assessment of Negative Symptoms and the Scale for the Assessment of Positive Symptoms (SAPS). We evaluated CT with the Childhood Trauma Questionnaire (CTQ). UHR group was also assessed with the Calgary Depression Scale for Schizophrenia. RESULTS: The emotional and physical abuse, physical and emotionalneglect subscale scores and CTQ total score of both the UHR group and FES group were higher than the control group. However, the CTQ total score and subscale scores did not differ between FES and UHR groups. UHR group had more Schneiderian symptoms in terms of both number and severity, and severity of sexual abuse was found to be correlated with SAPS scores especially for the 'commenting voices' item. The CTQ emotional abuse and neglect scores were correlated with the severity of depression. FES patients with higher CTQ scores obtained higher total scores on SAPS and higher total scores on Schneiderian items. CONCLUSION: We found that CT is related to the severity of psychotic symptoms in both FES and UHR groups. Therefore, it is possible that interventions aimed at preventing CT in children would reduce the manifestation of psychosis among young people.

Altered metabolic integrity of corpus callosum among individuals at ultra high risk of schizophrenia and first-episode patients.

BACKGROUND: The disconnectivity hypothesis as part of the neurodevelopmental model of schizophrenia states that an abnormality in brain development causing impaired corticocortical or interhemispheric connectivity leads to cognitive deficits and symptoms of the illness. Previous studies showed the altered morphology of corpus callosum in patients with schizophrenia. We investigated the metabolic integrity of corpus callosum of individuals at ultra high risk (UHR) of developing schizophrenia and first-episode patients. METHODS: We studied 17 individuals at UHR of developing schizophrenia, 14 first-episode schizophrenia patients, and 30 healthy control subjects. We measured the absolute concentrations of neurometabolites and T2 relaxation time of tissue water (T2(B)) in the genu region of corpus callosum by using proton magnetic resonance spectroscopy. RESULTS: N-acetylaspartate (NAA) concentrations were decreased and T2(B) values were prolonged in the UHR cases as well as in the first-episode patients, compared with the control subjects. The difference between the NAA concentrations of the UHR cases and first-episode patients was also significant. The NAA concentrations of the UHR cases and first-episode patients were correlated with the severity of negative symptoms. CONCLUSIONS: We demonstrated the disrupted metabolic integrity of corpus callosum among individuals at UHR of schizophrenia and the first-episode patients.