Tuula Kieseppa

The Effect of Processing Speed on Cognitive Functioning in Patients with Familial Bipolar I Disorder and Their Unaffected Relatives

Background: Despite increasing evidence of cognitive dysfunctions in bipolar I disorder, there is no specific neuropsychological profile of the disorder. Sampling and Method: The aim of the present study was to investigate the effect of processing speed on other cognitive functions in a population-based sample of 32 familial bipolar I disorder patients, their 40 unaffected first-degree relatives and 55 controls. A neuropsychological test battery was administered to all participants, and the effect of processing speed on other cognitive functions was analyzed with the digit symbol subtest of the Wechsler Adult Intelligence Scale-Revised both in within- and between-group comparisons. Results: After adjusting for the effect of processing speed, only small differences were detected in short-delay cued recall and in long-delay memory between patients and controls, as well as between patients and relatives. Relatives scored better than controls only in verbal ability. Processing speed had a significant effect on nearly all scores, differing by group when patients, relatives and controls were examined separately, the effect being most extensive in patients. Conclusions: These results support the view that impaired processing speed in particular contributes to a range of cognitive dysfunctions in bipolar disorder. However, it may not be specific to bipolar I disorder and can possibly be considered a shared endophenotype with other mental disorders.

Cortical salience network activation precedes the development of delusion severity.

BACKGROUNDnDelusion is the most characteristic symptom of psychosis. While researchers suggested an association between changes of the cortical salience network (CSN) and delusion, whether these CSN findings are a cause or a consequence of delusion remains unknown.nnnMETHODnTo assess the effect of CSN functioning to forthcoming changes in delusion scores, we measured brain activation with 3-T functional magnetic resonance imaging in two independent samples of first-episode psychosis patients (total of 27 patients and 23 healthy controls). During scanning, the patients evaluated statements about whether an individuals psychosis-related experiences should be described as a mental illness, and control statements that were also evaluated by healthy controls. Symptoms were assessed at the baseline and at 2 months follow-up with Brief Psychiatric Rating Scale.nnnRESULTSnBoth tasks activated the CSN in comparison with rest. Activation of CSN (illness evaluation v. control task contrast) in patients positively correlated with worsening of or less improvement in delusions at the 2-month follow-up assessment. This finding was independent of delusion and clinical insight scores at the baseline evaluation.nnnCONCLUSIONSnOur findings link symptom-evaluation-related CSN functioning to severity of delusion and, importantly, add a new layer of evidence for the contribution of CSN functioning to the longitudinal course of delusions.

S66. THEORY OF MIND IN A FIRST-EPISODE PSYCHOSIS POPULATION USING THE HINTING TASK

Abstract Background Impaired social functioning is one of the most apparent features of psychotic disorders. Deficits in social cognition may explain impaired functioning even more than the other cognitive deficits related to psychosis. Of the areas of social cognition, especially relevant to psychosis appear to be deficiencies in theory of mind (ToM), the ability to perceive and interpret the mental states of others, or “mentalizing”. Currently, it is unclear to what extent general cognitive deficits explain impairment in ToM. We wanted to explore 1) the possible difference in ToM between first-episode psychosis (FEP) patients and controls, 2) whether diagnosis group (schizophrenia vs. other psychotic disorders) and level of functioning are associated with ToM, and 3) to what extent these differences are explained by general cognitive performance. Methods This study examined ToM in young adults with FEP (n=66). Of those, 25 had schizophrenia and the rest were diagnosed with other psychotic disorders. Age- and gender-matched controls were identified from the Population Information System (n=62). The participants were administered a broad neuropsychological assessment, part of which was the Hinting Task assessing ToM. With 10 short discussions in everyday situations, the Hinting Task assesses the ability to conclude, from indirect speech, what another person really means. A factor score of the Hinting Task was formed, taking into account the varying difficulty level and relevance of the 10 items. To investigate the association between ToM and general cognitive functions, we summarized non-social cognitive performance constructing a “g factor”, which was used as an overall index of general cognitive performance. Results The internal consistency of the Hinting Task calculated from the dichotomized data was modest, with McDonald’s categorical omega estimated at .57 (95 % CI .36, .71). In the single dimensional factor solution, items 8 and 9 had the weakest loadings and item 10 the strongest. Items 9 and 10 of the Hinting Task were the easiest, and items 1 and 8 were the most difficult. Participants with FEP (mean score 16.0) performed worse than controls (mean score 17.4) on the Hinting Task (Cohen’s d=0.50 calculated from factor scores). However, the difference between FEP and control groups was no longer significant when general cognition was controlled for. 75 % of the variance between the groups was explained by general cognitive deficits, especially impaired processing speed (WAIS-III Digit Symbol) and episodic memory (WMS-III Logical Memory). When the FEP group was divided according to diagnosis, those with schizophrenia scored lower on the Hinting Task than the other psychosis patients. The ToM difference between individuals with schizophrenia and controls (Cohen’s d=1.1) remained significant even when general cognitive performance was controlled for. In contrast, those with other psychotic disorders than schizophrenia did not differ from controls. ToM performance of the best functioning patient group (20 patients who had a GAF score ≥50, Hinting Task mean score 17.8) did not differ from that of the control group. Discussion Based on this study, and supporting previous findings (Bora & Pantelis, Schizophr. Res. 2013), deficits in ToM were already present in early psychosis. They were largely overlapping with deficits in general cognitive processes. However, and in line with previous meta-analytical findings (Sprong et al., Br. J. Psychiatry 2007), in a subgroup of the FEP patients with schizophrenia, impairments in ToM remained after controlling for overall cognitive functioning. In conclusion, specific deficits in ToM could be found in schizophrenia, independent from general cognitive deficits.

Structural Magnetic Resonance Imaging in Bipolar Disorder: An International Collaborative Mega-Analysis of Individual Adult Patient Data

Background: There is substantial inconsistency in results of brain structural magnetic resonance imaging studies in adult bipolar disorder.This is likely consequent upon limited statistical power of studies together with their clinical and methodological heterogeneity. The current study was undertaken to perform an international collaborative mega-analysis of regional volumetric measurements of individual patient and healthy subject data, to optimize statistical power, detect case-control differences, assess the association of psychotropic medication usage with brain structural variation, and detect other possible sources of heterogeneity. Methods: Eleven international research groups contributed published and unpublished data on 321 individuals with bipolar disorder I and 442 healthy subjects. We used linear mixed effects regression models to evaluate differences in brain structure between patient groups. Results: Individuals with bipolar disorder had increased right lateral ventricular, left temporal lo...