1
|
Executive functioning and psychopathological profile in relatives of individuals with deficit v. non-deficit schizophrenia: a pilot study. Epidemiol Psychiatr Sci 2014; 23:85-97. [PMID: 23545096 PMCID: PMC6998377 DOI: 10.1017/s2045796013000140] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Aims. Heterogeneity of schizophrenia is known to be reflected in neuropsychological functioning of patients, but its expression in relatives is understudied. This study aims at exploring relationship between executive functioning and clinical profiles of first-degree relatives of patients who are classified as having or not having the deficit subtype of schizophrenia (DSRELs v. non-DSRELs), with the prediction of greater executive impairment in DSRELs. Methods. DSRELs (n = 15) and non-DSRELs (n = 40) were compared with community controls (CCs, n = 55) on executive functioning measured by the Wisconsin Card Sorting Test (WCST) and the phonemic verbal fluency (PVF), and clinical measures. Effects of psychopathology and intelligence quotient (IQ) measures were investigated to determine their association with executive performance. Results. DSRELs showed more executive dysfunction on WCST and poorer social functioning than CCs and more severe negative symptoms than non-DSRELs. Differences on WCST-categories achieved (WCST-CA) remained significant after adjustment for clinical confounders and IQ. WCST-CA was associated with apathy and paranoid ideation only within the DSREL subgroup. Conclusions. Executive functioning and negative symptoms are severely impaired in first-degree relatives of deficit syndrome patients, thus suggesting that some neurocognitive deficits in patients may be transmitted within families according to the pathophysiology of the probands.
Collapse
|
2
|
Goghari VM. Executive functioning-related brain abnormalities associated with the genetic liability for schizophrenia: an activation likelihood estimation meta-analysis. Psychol Med 2011; 41:1239-1252. [PMID: 20942994 DOI: 10.1017/s0033291710001972] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Relatives of schizophrenia patients demonstrate abnormalities in prefrontal cortical activation during executive processing as measured by functional neuroimaging, albeit not consistently. A meta-analysis was conducted to determine whether reliable patterns of brain hypo- and hyperactivity, especially in the middle frontal region, were present in the relatives of patients. METHOD Seventeen studies, containing 18 samples of relatives and controls, were included in this meta-analysis. Studies were included if relatives of schizophrenia patients were compared to controls, an executive processing task was used, and standard space coordinates were reported for the functional activations. Activation likelihood estimation (ALE) was implemented to find convergence across functional neuroimaging experiment coordinates. A separate analysis was conducted to assess the potential impact of a priori hypothesis testing used in region-of-interest (ROI) approaches on the meta-analysis results. RESULTS Relatives demonstrated hypo- and hyperactivity in statistically overlapping right middle frontal regions [Brodmann area (BA) 9/10]. Use of an ROI analysis that a priori focused on prefrontal regions resulted in more findings of reduced activity in the middle frontal region. CONCLUSIONS The cortical regions identified by this meta-analysis could potentially serve as intermediate biological markers in the search for candidate genes for schizophrenia. As neurocognitive deficits are related to functional impairments in patients, a better understanding of neural and genetic vulnerabilities would be beneficial in our efforts to remediate these important deficits.
Collapse
Affiliation(s)
- V M Goghari
- Department of Psychology and Psychiatry, University of Calgary, Calgary, AB, Canada.
| |
Collapse
|
3
|
Li T, Ma X, Hu X, Wang Y, Yan C, Meng H, Liu X, Toulopoulou T, Murray RM, Collier DA. PRODH gene is associated with executive function in schizophrenic families. Am J Med Genet B Neuropsychiatr Genet 2008; 147B:654-7. [PMID: 18163391 DOI: 10.1002/ajmg.b.30648] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The aim of this study was to investigate the relationship between polymorphisms in the PRODH and COMT genes and selected neurocognitive functions. Six SNPs in PRODH and two SNPs in COMT were genotyped in 167 first-episode schizophrenic families who had been assessed by a set of 14 neuropsychological tests. Neuropsychological measures were selected as quantitative traits for association analysis. The haplotype of SNPs PRODH 1945T/C and PRODH 1852G/A was associated with impaired performance on the Tower of Hanoi, a problem-solving task mainly reflecting planning capacity. There was no significant evidence for association with any other neuropsychological traits for other SNPs or haplotypes of paired SNPs in the two genes. This study takes previous findings of association between PRODH and schizophrenia further by associating variation within the gene with performance on a neurocognitive trait characteristic of the illness. It fails to confirm previous reports of an association between COMT and cognitive function.
Collapse
Affiliation(s)
- Tao Li
- Psychiatric Laboratory, Department of Psychiatry, West China Hospital, Sichuan University, Sichuan, China.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
4
|
Ma X, Wang Q, Sham PC, Liu X, Rabe-Hesketh S, Sun X, Hu J, Meng H, Chen W, Chen EYH, Deng W, Chan RCK, Murray RM, Collier DA, Li T. Neurocognitive deficits in first-episode schizophrenic patients and their first-degree relatives. Am J Med Genet B Neuropsychiatr Genet 2007; 144B:407-16. [PMID: 17440937 DOI: 10.1002/ajmg.b.30330] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Some neuropsychological abilities, particularly those affecting memory, attention and executive function, are impaired amongst both schizophrenic patients and their unaffected relatives, implying that these deficits are at least partly genetic in origin. However neuropsychological performance can be altered by medication, and has rarely been examined in first onset, drug naive patients. The objective of this study was to determine whether selected neurocognitive abilities are impaired in first-onset schizophrenic patients and their relatives compared to controls. We examined attention and speed of information processing, memory and learning, verbal function, visuoconstructive abilities and executive function in 207 first-episode schizophrenic patients (163 of whom were drug naïve), 322 of their first-degree relatives and 133 unrelated normal controls. The data were subjected to multilevel modeling to compare neurocognitive performance between schizophrenic probands, relatives and controls while taking into account potential correlations among members of the same family; age, gender, and years of education were included as covariates. Of the three groups, schizophrenic patients performed poorest at all neuropsychological tests, suggestive of a broad range of neurocognitive deficits. Their first-degree relatives showed a narrower pattern of poor performance at Digit Symbol, Digit Span, Trail Making, Verbal Fluency test, Tower of Hanoi, and WCST-M tests. Our findings show that selected neurocognitive deficits especially attention and executive function are impaired in the families of schizophrenic patients. These patterns of neurocognitive deficits may represent "endophenotypes" denoting varying degrees of vulnerability to schizophrenia and may be of value in future molecular genetic studies.
Collapse
Affiliation(s)
- Xiaohong Ma
- Psychiatric Laboratory and Department of Psychiatry, West China Hospital, Sichuan University, Chengdu, P R China
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Reichenberg A, Weiser M, Caspi A, Knobler HY, Lubin G, Harvey PD, Rabinowitz J, Davidson M. Premorbid intellectual functioning and risk of schizophrenia and spectrum disorders. J Clin Exp Neuropsychol 2006; 28:193-207. [PMID: 16484093 DOI: 10.1080/13803390500360372] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Evidence from longitudinal studies indicates that lower IQ score in childhood and early adolescence increases risk of schizophrenia and schizophrenia spectrum disorders (SSD). This study investigated the association between premorbid IQ and risk of SSD in a population-based cohort of 17-year-old conscripts. Fifty four thousand males assessed by the Israeli Draft Board during two consecutive years were followed by means of the Israeli National Psychiatric Hospitalization Case Registry for up to 11 years. Tests of verbal and non-verbal reasoning, mathematical knowledge and instructions comprehension and several psychosocial variables were recorded by the Draft Board. Risk for SSD increased with decreasing IQ score. Only poorer non-verbal reasoning conferred a significant increased risk for SSD after taking into account general intellectual ability. IQ was not associated with age of onset. These results confirm the importance of low intellectual functioning as a risk factor for SSD. This is unlikely to be due to prodrome.
Collapse
Affiliation(s)
- Abraham Reichenberg
- Department of Psychiatry, Mount Sinai School of Medicine, One Gustave L Levey Place, Box 1230, New York, NY 10029, USA.
| | | | | | | | | | | | | | | |
Collapse
|
6
|
Trandafir A, Méary A, Schürhoff F, Leboyer M, Szöke A. Memory tests in first-degree adult relatives of schizophrenic patients: a meta-analysis. Schizophr Res 2006; 81:217-26. [PMID: 16246526 PMCID: PMC1950161 DOI: 10.1016/j.schres.2005.09.005] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2005] [Revised: 09/09/2005] [Accepted: 09/10/2005] [Indexed: 11/27/2022]
Abstract
BACKGROUND Memory deficits have been clearly demonstrated in schizophrenic patients. However, studies of memory performances in their relatives compared to normal controls provide conflicting results. A meta-analysis was carried out to synthesize all the published data. Unlike previous meta-analyses, which were based on composite scores, we analyzed each memory test separately. This prevents theoretically questionable choices in grouping variables, leads to results with clearer implications for applied research (e.g. the best choice of a test according to its sensitivity) and is more productive in suggesting explanatory hypotheses. METHOD We initially selected 77 potentially relevant articles, but only 19 met our inclusion criteria. These articles provided data on eight different tasks, from five different memory tests: four tests from the Wechsler Memory Scale (WMS) and the California Verbal Learning Test (CVLT). For each task, we assessed data homogeneity, identified the outliers if any and then estimated effect sizes and tested publication bias using funnel plots. RESULTS Adult relatives of schizophrenic patients were significantly impaired on most, but not all, tasks. The largest deficits were observed for the verbal paired associates test, the logical stories the digit span forward test and the digit span backward test. We found no significant differences in tasks of delayed recall, when deficits in immediate conditions (reflecting encoding) were taken into account. CONCLUSIONS Adult relatives of schizophrenic patients have wide but not severe memory impairments. The size of estimated effects suggests that encoding processes are impaired, whereas storage and retrieval processes are relatively unaffected.
Collapse
Affiliation(s)
- Anca Trandafir
- Service de psychiatrie
AP-HP Hôpital Henri Mondor Hôpital Albert ChenevierCréteil,FR
- Neurobiologie et Psychiatrie
INSERM : U513Université Paris XII Val de Marne8, Rue du Général Sarrail
Créteil,FR
| | - Alexandre Méary
- Service de psychiatrie
AP-HP Hôpital Henri Mondor Hôpital Albert ChenevierCréteil,FR
- Neurobiologie et Psychiatrie
INSERM : U513Université Paris XII Val de Marne8, Rue du Général Sarrail
Créteil,FR
- Service de pharmacologie clinique
AP-HP Hôpital Henri MondorUniversité Paris XII Val de Marne51, av du Maréchal de Tassigny, Créteil,FR
| | - Franck Schürhoff
- Service de psychiatrie
AP-HP Hôpital Henri Mondor Hôpital Albert ChenevierCréteil,FR
- Neurobiologie et Psychiatrie
INSERM : U513Université Paris XII Val de Marne8, Rue du Général Sarrail
Créteil,FR
| | - Marion Leboyer
- Service de psychiatrie
AP-HP Hôpital Henri Mondor Hôpital Albert ChenevierCréteil,FR
- Neurobiologie et Psychiatrie
INSERM : U513Université Paris XII Val de Marne8, Rue du Général Sarrail
Créteil,FR
| | - Andrei Szöke
- Service de psychiatrie
AP-HP Hôpital Henri Mondor Hôpital Albert ChenevierCréteil,FR
- Neurobiologie et Psychiatrie
INSERM : U513Université Paris XII Val de Marne8, Rue du Général Sarrail
Créteil,FR
| |
Collapse
|
7
|
Ettinger U, Kumari V, Crawford TJ, Corr PJ, Das M, Zachariah E, Hughes C, Sumich AL, Rabe-Hesketh S, Sharma T. Smooth pursuit and antisaccade eye movements in siblings discordant for schizophrenia. J Psychiatr Res 2004; 38:177-84. [PMID: 14757332 DOI: 10.1016/s0022-3956(03)00105-5] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Smooth pursuit eye movement (SPEM) and antisaccade deficits have been proposed as endophenotypes in the search for schizophrenia genes. We assessed these measures in 24 schizophrenia patients, 24 of their healthy siblings, and 24 healthy controls closely matched to the siblings. Between-group differences were assessed using a random effects regression model taking into account the relatedness between patients and siblings. Patients showed reduced SPEM gain, increased frequency of saccades during pursuit, increased antisaccade error rate, and reduced antisaccade gain compared to controls. Siblings performed intermediate, i.e. between patients and controls, on most measures, but were particularly characterised by reduced antisaccade gain. SPEM gain at one target velocity was significantly correlated between patients and siblings, highlighting the necessity of taking into account within-family correlations in the statistical analysis of between-group differences. It is concluded that subtle SPEM and antisaccade deficits are observed in clinically unaffected siblings of schizophrenia patients; these deficits may be useful markers of genetic liability to schizophrenia.
Collapse
Affiliation(s)
- Ulrich Ettinger
- Division of Psychological Medicine, Institute of Psychiatry, UK
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Appels MCM, Sitskoorn MM, Westers P, Lems E, Kahn RS. Cognitive dysfunctions in parents of schizophrenic patients parallel the deficits found in patients. Schizophr Res 2003; 63:285-93. [PMID: 12957707 DOI: 10.1016/s0920-9964(02)00342-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Schizophrenia is characterized by a global cognitive impairment, with varying degrees of deficit in all ability domains. Since genetic factors are important in the etiology of schizophrenia we investigated whether parents of schizophrenic patients also show cognitive deficits, particularly on those cognitive ability domains that are most severely affected in patients. Both biological parents of 37 patients with schizophrenia (N=74 subjects) and 28 comparable healthy married control couples (N=56 subjects) were included. A comprehensive and standardized cognitive battery was used including tests measuring verbal memory, executive functioning, language, attention, and psychomotor functioning. Parents of patients differed from control couples on those cognitive constructs that are generally considered to be most impaired in schizophrenic patients, i.e. global verbal memory, bilateral motor skill, continuous performance, and word fluency. In addition, parents differed significantly from control couples on some other cognitive constructs on which patients show a smaller but also significant difference compared to healthy controls, i.e. unilateral motor skill and digit span. Results suggest that the cognitive constructs on which patients show relatively most severe impairment may prove suitable as endophenotypic markers in schizophrenia.
Collapse
Affiliation(s)
- Melanie C M Appels
- Department of Psychiatry, University Medical Center, PO Box 85500, 3508 GA, Utrecht, The Netherlands.
| | | | | | | | | |
Collapse
|
9
|
Abstract
Schizophrenia is a biologic disorder whose etiology involves a combination of genetic and environmental risk factors. In this review, the authors update the conceptual basis of schizotaxia, consider evidence for its validity, and look toward its likely evolution in the future.
Collapse
Affiliation(s)
- Ming T Tsuang
- Department of Psychiatry at the Massachusetts Mental Health Center, Harvard Medical School, 74 Fernwood Road, Boston, MA 02115, USA.
| | | | | | | |
Collapse
|
10
|
Faraone SV, Seidman LJ, Kremen WS, Kennedy D, Makris N, Caviness VS, Goldstein J, Tsuang MT. Structural brain abnormalities among relatives of patients with schizophrenia: implications for linkage studies. Schizophr Res 2003; 60:125-40. [PMID: 12591577 DOI: 10.1016/s0920-9964(02)00304-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Several studies suggest that the nonschizophrenic relatives of schizophrenic patients exhibit structural brain abnormalities that may be manifestations of genes that predispose to schizophrenia. In this work, we examine the utility of such measures for linkage analyses. Subjects were 45 nonpsychotic first-degree adult relatives of schizophrenic patients and 48 normal controls. Sixty contiguous 3-mm coronal, T1-weighted 3D magnetic resonance images of the entire brain were acquired on a 1.5-T magnet. We used factor analysis to derive MRI-based phenotypes for analysis. The factor analyses produced three factors that significantly discriminated relatives from controls. We used a linear combination of the three factor scores to derive an MRI phenotype. A receiver operating characteristic (ROC) analysis of this phenotype estimated an area under the curve (AUC) statistic of 0.85. The phenotype also discriminated nonpsychotic relatives having two schizophrenic relatives from those having only one. The nonpsychotic relatives of schizophrenic patients show deviant values on MRI measures of brain structure and the distribution of these deviations among relatives and controls suggests that if these results can be replicated, an MRI-derived phenotype could be useful for genetic linkage and association analyses.
Collapse
Affiliation(s)
- Stephen V Faraone
- Harvard Medical School Department of Psychiatry at the Massachusetts Mental Health Center, Boston, MA, USA.
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Rabe-Hesketh S, Toulopoulou T, Murray RM. Multilevel Modeling of Cognitive Function in Schizophrenic Patients and Their First Degree Relatives. MULTIVARIATE BEHAVIORAL RESEARCH 2001; 36:279-298. [PMID: 26822112 DOI: 10.1207/s15327906mbr3602_07] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We describe multilevel modeling of cognitive function in subjects with schizophrenia, their healthy first degree relatives and controls. The purpose of the study was to compare mean cognitive performance between the three groups after adjusting for various covariates, as well as to investigate differences in the variances. Multilevel models were required because subjects were nested within families and some of the measures were repeated several times on the same subject. The following four methodological issues that arose during the analysis of the data are discussed. First, when the random effects distribution was not normal, non-parametric maximum likelihood (NPML) was employed, leading to a different conclusion than the conventional multilevel model regarding one of the main study hypotheses. Second, the between-subject (within-family) variance was allowed to differ between the three groups. This corresponded to the variance at level 1 or level 2 depending on whether repeated measures were analyzed. Third, a positively skewed response was analyzed using a number of different generalized linear mixed models. Finally, penalized quasilikelihood (PQL) estimates for a binomial response were compared with estimates obtained using Gaussian quadrature. A small simulation study was carried out to assess the accuracy of the latter.
Collapse
|
12
|
Abstract
Evidence for genetic factors in schizophrenia is reviewed with regard to family, twin and adoption studies, and recent advances in molecular genetic technology are applied to explore possible gene loci susceptible to schizophrenia. Application of neuropsychological and neuroimaging methodologies are also reviewed with an aim to develop criteria for defining phenotypes for genetic studies.
Collapse
Affiliation(s)
- M T Tsuang
- Harvard Medical School Department of Psychiatry, Massachusetts Mental Health Center, Boston 02115, USA
| |
Collapse
|
13
|
Tsuang MT. Schizophrenia: vulnerability versus disease. DIALOGUES IN CLINICAL NEUROSCIENCE 2000. [PMID: 22034456 PMCID: PMC3181615 DOI: 10.31887/dcns.2000.2.3/mtsuang] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
One of the most important trends in the treatment of schizophrenia involves its early diagnosis and intervention. The ultimate goal of research is the prevention of the disorder, A major impediment to the development of prevention strategies, however, is that we do not yet know what the liability for schizophrenia is before the onset of psychosis. Consequently, early treatment attempts are focused on the “prodrome,” which involves the early symptoms of psychosis. In a companion paper, we recently suggested that prevention work should focus not only on the prodrome, but also on “schizotaxia,” which is a clinically meaningful condition that may reflect the vulnerability to schizophrenia in the absence of psychosis. Because schizotaxia can be assessed prior to the prodrome, studies of schizotaxia might lead to more effective prevention programs. We continue the characterization of schizotaxia in this paper by focusing on the etiological roots of schizotaxia, plus its likely neurodevelopmental course, clinical expression, and treatment. Finally, the importance of including neurobiological variables in the conceptualization and eventual diagnosis of schizotaxia is reviewed.
Collapse
|
14
|
Faraone SV, Seidman LJ, Kremen WS, Toomey R, Pepple JR, Tsuang MT. Neuropsychologic functioning among the nonpsychotic relatives of schizophrenic patients: the effect of genetic loading. Biol Psychiatry 2000; 48:120-6. [PMID: 10903408 DOI: 10.1016/s0006-3223(99)00263-2] [Citation(s) in RCA: 152] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND We previously reported that the nonpsychotic relatives of schizophrenic patients exhibited disturbances in executive functioning, verbal and visual memory, auditory attention, mental control, and verbal ability. In a 4-year follow-up, we showed that the discriminating power of most of these tests was stable over time. METHODS In this report we compare 41 nonpsychotic persons who have only one schizophrenic first-degree relative (simplex families) with 36 nonpsychotic persons who have two schizophrenic first-degree relatives (multiplex families). Our goal was to test a hypothesis that neuropsychologic deficits would be worse among the latter. RESULTS Relatives from multiplex families differed significantly from controls on estimated intelligence, immediate and delayed logical memories, and immediate visual reproductions. In contrast, in comparisons with controls, relatives from simplex families only differed on immediate logical memories. Comparisons between relatives from multiplex and simplex families showed that the former group had significantly worse scores for estimated intelligence, immediate and delayed logical memories, and immediate visual reproductions. We also found group x gender interactions: the worse performance of the multiplex group was seen for females. CONCLUSIONS These results are consistent with the idea that neuropsychologic deficits in relatives of schizophrenic patients reflect their degree of genetic predisposition to schizophrenia. They also suggest hypotheses about gender differences in the familial transmission of the disorder.
Collapse
Affiliation(s)
- S V Faraone
- Harvard Medical School Department of Psychiatry at the Massachusetts Mental Health Center and Brockton/West Roxbury VA Medical Center, Brockton, Massachusetts, USA
| | | | | | | | | | | |
Collapse
|
15
|
Laurent A, Moreaud O, Bosson JL, Naegele B, Boucharlat J, Saoud M, Dalery J, D'Amato T. Neuropsychological functioning among non-psychotic siblings and parents of schizophrenic patients. Psychiatry Res 1999; 87:147-57. [PMID: 10579548 DOI: 10.1016/s0165-1781(99)00064-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Several studies have shown subtle neuropsychological deficits in healthy relatives of schizophrenic patients. However, older relatives and parents have been less frequently assessed than younger adult relatives and siblings. Furthermore, some areas of neuropsychological functioning such as memory and learning have been little studied. Thirty-seven 22-70-year-old non-psychotic parents and siblings of schizophrenic patients were compared to 37 healthy control subjects on a battery of neuropsychological tests (Trail Making, parts A and B, verbal fluency, Wisconsin Card Sorting Test, and four subtests of the Wechsler Memory Scale-Revised: logical memory, design reproduction, verbal paired associates and digit span). Relatives did not differ from control subjects on Wisconsin Card Sorting Test performance and on visual memory, but were significantly impaired on verbal fluency; more subtle deficits were found on Trail Making, part B, digit span and paired associates. A higher proportion of relatives than control subjects showed impairment on verbal fluency and verbal memory. These neuropsychological weaknesseswere present as much in siblings as in parents of schizophrenic patients, and age did not cancel differences between relatives and control subjects. Thus, these subtle deficits seem to be potential phenotypic markers of schizophrenia.
Collapse
Affiliation(s)
- A Laurent
- Department of Psychiatry, University Hospital of Grenoble, France.
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Kremen WS, Faraone SV, Seidman LJ, Pepple JR, Tsuang MT. Neuropsychological risk indicators for schizophrenia: a preliminary study of female relatives of schizophrenic and bipolar probands. Psychiatry Res 1998; 79:227-40. [PMID: 9704870 DOI: 10.1016/s0165-1781(98)00042-0] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Evidence of subtle neuropsychological deficits in relatives of schizophrenic probands (REL-SZs) suggests that these are risk indicators for schizophrenia, but little is known about whether neuropsychological performance in REL-SZs differs from that in other groups of relatives. We compared neuropsychological function in female REL-SZs (n = 39), relatives of primarily psychotic bipolar disorder probands (REL-BPs; n = 15), and a normal control group (n = 44). After adjustment for expected intellectual ability (based on reading recognition), REL-SZs showed deficits in verbal and visual memory (Wechsler Memory Scale-Revised logical memories, visual reproductions), and auditory attention (dichotic digits) compared with either REL-BPs or control subjects. Memory, but not dichotic listening differences remained significant after adjusting for current IQ; however, average effect sizes after controlling for either reading or IQ were roughly comparable for these three parameters (d = 0.80, 0.71, and 0.69, respectively). REL-BPs and control subjects showed little difference. Although both schizophrenic and bipolar patients often manifest neuropsychological dysfunction, these preliminary findings indicate subtle neuropsychological deficits only in REL-SZs. Such differences suggest different underlying processes; neuropsychological impairment may, in part, reflect an expression of genetic liability to schizophrenia but not bipolar disorder. Replication with a larger REL-BP sample and with male relatives is needed to evaluate the generalizability of the results.
Collapse
Affiliation(s)
- W S Kremen
- Department of Psychiatry, University of California, Davis School of Medicine, Sacramento 95817, USA.
| | | | | | | | | |
Collapse
|
17
|
Toomey R, Faraone SV, Seidman LJ, Kremen WS, Pepple JR, Tsuang MT. Association of neuropsychological vulnerability markers in relatives of schizophrenic patients. Schizophr Res 1998; 31:89-98. [PMID: 9689713 DOI: 10.1016/s0920-9964(98)00025-5] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We investigated the association of neuropsychological risk indicators in a matched sample of first-degree relatives of schizophrenic patients (n = 54) and normal controls (n = 72). We focussed on three functions previously identified in a smaller, initial sample as putative risk indicators of the schizophrenia genotype: abstraction, verbal memory and auditory attention. The expanded sample of relatives displayed significantly lower scores than controls on abstraction, verbal memory and auditory attention. The relatives demonstrated significant intercorrelations among these three functions. The significant correlations among relatives between attention and verbal memory and between attention and abstraction differed significantly from these correlations among controls. We discuss how the use of multiple risk indicators may help us better identify those relatives that carry the schizophrenia genotype.
Collapse
Affiliation(s)
- R Toomey
- Harvard Institute of Psychiatric Epidemiology and Genetics, Boston, MA, USA.
| | | | | | | | | | | |
Collapse
|
18
|
Seidman LJ, Faraone SV, Goldstein JM, Goodman JM, Kremen WS, Matsuda G, Hoge EA, Kennedy D, Makris N, Caviness VS, Tsuang MT. Reduced subcortical brain volumes in nonpsychotic siblings of schizophrenic patients: a pilot magnetic resonance imaging study. AMERICAN JOURNAL OF MEDICAL GENETICS 1997; 74:507-14. [PMID: 9342202 DOI: 10.1002/(sici)1096-8628(19970919)74:5<507::aid-ajmg11>3.0.co;2-g] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Substantial evidence suggests that nonpsychotic relatives of schizophrenia patients manifest subtle abnormalities in communication, eye movements, event-related potentials, and neuropsychological processes of attention, reasoning, and memory. We sought to determine whether adult relatives without psychosis or schizophrenia spectrum diagnoses might also have structural brain abnormalities, particularly in subcortical regions found to be impaired in patients with schizophrenia itself. Subjects were six sisters of schizophrenic patients and eleven normal female controls. Sixty contiguous 3 mm coronal, T1-weighted 3D magnetic resonance images (MRI) of the entire brain were acquired on a 1.5 Tesla magnet. Cortical and subcortical gray and white matter was segmented using a semiautomated intensity contour mapping algorithm. Volumes were adjusted for total brain volumes. Adjusted gray matter subcortical volumes were significantly smaller in relatives than in controls in total hippocampus, right amygdala, right putamen, left thalamus, and brainstem. Relatives had significantly enlarged left and total inferior lateral ventricles. These results, though preliminary, suggest that some never-psychotic relatives of schizophrenic patients have abnormal brain structure. If replicated in a larger sample including both sexes, these results would suggest that the genetic liability to schizophrenia is also expressed as structural brain abnormalities.
Collapse
Affiliation(s)
- L J Seidman
- Department of Psychiatry at Massachusetts Mental Health Center, Harvard Medical School, Boston 02115, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|