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Vasilis P Bozikas

Publications and source records attributed to Vasilis P Bozikas.

At least 19 recordsLinked to original sources
PubMed2006

Impaired emotion perception in schizophrenia: a differential deficit.

We investigated previously reported contradictory findings regarding the nature of deficits in emotion perception among patients with schizophrenia. Some studies have concluded that such deficits are due to a generalized impairment in visual processing of faces, while others have found it to be restricted to facial emotional expressions. We examined 37 patients and 32 healthy controls, matched on age and education, using three computerized tests: matching facial identity, matching facial emotional expressions, and discrimination of subtle differences in the valence of facial emotional expressions. Our results showed impaired matching of emotions in patients with schizophrenia. This impairment did not manifest on tasks that depended on perceiving the identity of faces or cues of the relative valence of facial emotional expressions. Our findings support the differential deficit hypothesis of emotion perception in schizophrenia.

Adult↗
PubMed2006

Shared cognitive processes underlying performance on the Wisconsin Card Sorting Test and the Stroop Test in patients with schizophrenia: a measurement artifact?

We explored the hypothesis that, while sensitive to different aspects of executive functioning in patients with schizophrenia, the Wisconsin Card Sorting Test (WCST) and the Stroop Test also measure the same construct, namely, inhibitory control. Specifically, our goal was to confirm and extend previous findings [A. Rossi, E. Daneluzzo, P. Mattei, M. Bustini, M. Cassachia, P. Stratta, Wisconsin Card Sorting Test and Stroop performance in schizophrenia: a shared construct, Neurosci. Lett. 226 (1997) 87-90] by demonstrating the independence of this construct from other abilities necessary to successfully perform the tasks. More importantly, we sought to improve on this previous study by eliminating the influence of the variance of speed of responding. We examined 55 patients with schizophrenia and initially found that performance on the Stroop Color-Word condition could, indeed, be predicted only by the percentage of perseverative errors on the WCST, and not variables reflective of other cognitive skills, thus replicating and extending previous findings. Once we removed the influence of speed of responding from our measure, however, thus isolating the inhibitory process, this finding disappeared. Therefore, our findings highlight the importance of isolating the individual components of interest from complex measures before drawing conclusions regarding the cognitive processes underlying particular test performance.

Artifacts↗
PubMed2006

Community dysfunction in schizophrenia: rate-limiting factors.

The purpose of the present study was to investigate the impact of cognitive functioning, psychopathology, and severity of extrapyramidal side effects on community outcome in a group of Greek outpatients with schizophrenia. Participants were 40 outpatients with schizophrenia (25 men). Social adjustment was assessed with the Quality of Life Scale (QLS). Severity of symptoms of schizophrenia was measured with the Positive and Negative Syndrome Scale (PANNS), and extrapyramidal symptoms with the Extrapyramidal Symptom Rating Scale (ESRS). Finally, a battery of neuropsychological tests was administered in order to assess the following cognitive domains: executive functioning/set shifting, executive functioning/inhibition, fluency, verbal memory, visual memory, working memory, attention, visuospatial ability, and psychomotor speed/visual scanning. Total scores on the QLS were significantly correlated with negative symptoms, parkinsonism, and performance on the fluency tasks. Interpersonal relations subscale was significantly related with negative symptoms and fluency. No significant relationship was found between the Instrumental Role Functioning subscale and the PANSS, ESRS, or any cognitive domain. Scores on the Intrapsychic Foundation subscale were significantly correlated with negative symptoms and fluency. Finally, scores on the Common Objects and Activities subscale were significantly related with severity of negative symptoms, parkinsonism and visual memory. Our findings suggest that severity of negative symptoms, cognitive dysfunction, especially performance on fluency tasks and visual memory, as well as parkinsonism, are important determinants of functional outcome in schizophrenia.

Adult↗
PubMed2006

Urinary hesitancy and retention caused by ziprasidone.

We report the case of a patient with schizophrenia who developed urinary hesitancy and eventually urinary retention, 6 months after continuous treatment with ziprasidone; he had been administered no other medication during this time. The micturition difficulties resolved immediately upon discontinuation of ziprasidone.

Adult↗
PubMed2006

Impaired perception of affective prosody in schizophrenia.

The authors aimed to explore schizophrenia patients' ability to perceive affective prosody. Specifically, certain emotions that may be more troublesome for patients and possible gender differences in prosody perception were assessed. Thirty six schizophrenia patients and 32 age-, education-, and gender-matched healthy comparison subjects assessed on an affective prosody test were examined. Patients were impaired on recognition of affective prosody overall, and their difficulties with prosody perception may be attributed to those emotions with negative valence, specifically anger and sadness. Findings revealed that only male patients were impaired on prosody perception. Deficits in the perception of affective prosody were principally evident in emotions with negative valence and male patients with schizophrenia. Future studies should explore the influence of these deficits on social and interpersonal functioning more directly.

Adult↗
PubMed2005

Deficits in sustained attention in schizophrenia but not in bipolar disorder.

The aim of the present study was to investigate sustained attention in remitted patients with bipolar disorder and in patients with schizophrenia, as compared to each other and to healthy controls; a secondary aim was to investigate the correlations of different symptom dimensions with performance on sustained attention in the two patient groups. Participants were 29 (18 men) outpatients with schizophrenia (SZ), 19 (8 men) patients with bipolar disorder I (BP) in remission, and 30 (15 men) healthy controls (HC); all three groups were matched on age, sex ratio, and level of education. Symptom severity (positive symptoms, negative symptoms, and general psychopathology) of patients with SZ were assessed with the Greek version of the Positive and Negative Syndrome Scale (PANSS); residual affective symptoms of patients with BP were assessed with the Young Mania Rating Scale (YMRS) and the Montgomery-Asberg Depression Rating Scale (MADRS). Sustained attention was measured by means of the Penn Continuous Performance Test (PCPT). The three groups differed significantly on the PCPT scores. Patients with SZ performed more poorly than both the BP and HC groups, whereas patients with BP did not differ significantly from HC. Performance on the PCPT did not correlate significantly with scores on the YMRS and MADRS in patients with BP. Also, scores on the PCPT did not correlate significantly with scores on any of the three subscales of the PANSS. Outpatients with schizophrenia presented deficits in sustained attention, whereas patients with bipolar disorder I in remission did not manifest such impairment. These results imply that impaired sustained attention might be a more enduring deficit in schizophrenia than it appears to be in bipolar disorder.

Adolescent↗
PubMed2005

Disproportionate impairment in semantic verbal fluency in schizophrenia: differential deficit in clustering.

The purpose of the current study was to investigate whether patients with schizophrenia present disproportionate impairment in semantic, relative to phonemic, fluency. Specifically, we explored whether this impairment could be explained by differential deficits in clustering or switching strategies. The Greek Verbal Fluency Test was administered to 119 patients with schizophrenia and 150 age-, education-, and gender-matched healthy controls. We calculated the total number of words generated, the number of cluster related words, and the number of switches on the semantic and phonological fluency tasks separately. Patients with schizophrenia generated fewer total words, cluster related words and switches than healthy controls on both fluency tasks. When controlling for the total number of words produced, however, the differences between the two groups in the number of cluster related words and switches disappeared. We found a disproportionate impairment in semantic, compared with phonemic, fluency in schizophrenia for total word production and the number of cluster related words, but not for the number of switches. In conclusion, patients with schizophrenia used the same strategies as healthy controls to perform on a word fluency test, but they used them less effectively. Disproportionate impairment in semantic fluency in schizophrenia resulted from a differential deficit only in clustering. Therefore, disproportionately impaired category fluency in schizophrenia may be primarily due to disorganization and not to inefficient access to and retrieval from semantic store.

Diagnostic and Statistical Manual of Mental Disord↗
PubMed2005

Olanzapine-induced leucopenia and neutropenia.

Atypical antipsychotics, including olanzapine, were originally expected to reduce the risk of haematological toxicity and to be safe alternatives to clozapine. We report a case of patient who developed leucopenia and neutropenia during treatment with olanzapine.

Aged↗
PubMed2005

Pathological correlates of poststroke depression in elderly patients.

OBJECTIVE: The authors examined the relationship between poststroke depression and location of stroke. METHODS: They performed a clinicopathological analysis of 95 consecutively autopsied elderly initial-stroke survivors. RESULTS: The severity of brain vessel arteriosclerosis and frequency of brain vascular lesions were not significantly different between 21 cases with poststroke depression and 74 cases without. Earlier death was the only variable significantly associated with poststroke depression. No lesion pattern characterized the depression group. CONCLUSIONS: Neuropathological data confirm that depression is associated with worse prognosis in elderly stroke patients and lend support to the hypothesis that psychological rather than neurological factors are the main determinants of poststroke depression.

Aged↗
PubMed2005

Tardive nocturnal akathisia due to clozapine treatment.

In the following case report we present a 43-year-old male patient diagnosed with schizophrenia, paranoid type, who exhibited nocturnal tardive akathisia or pseydoakathisia approximately one year after being treated with clozapine 300 mg per day. Because of the low occurrence of akathisia due to clozapine, the episodes of restlessness were at first considered as a sign of worsening of the patient's psychopathology. Since the patient was resistant to other antipsychotic agents, clozapine was reinitiated. A week later, the patient once again exhibited episodes of restlessness. This time, the episodes were diagnosed as akathisia and the patient was treated with biperidene and lorazepam, while he had already been on propanolol for cardiovascular reasons. The episodes continued without any change in frequency or severity. Therefore, treatment with clozapine was discontinued and the patient was started on a new regimen with ziprasidone. Three days later, the episodes that caused distress to the patient resolved. Thus, it is possible that apart from episodes of acute akathisia, episodes of tardive akathisia or pseydoakathisia can also occur in patients treated with atypical antipsychotics.

Adult↗
PubMed2004

No increased levels of the nicotine metabolite cotinine in smokers with schizophrenia.

The prevalence of smoking cigarettes has repeatedly been found to be greater in schizophrenia as compared with other psychiatric patients and the general population. Patients with schizophrenia have been found to engage in heavy smoking and consumption of higher doses of nicotine, probably by deeper inhalation of cigarettes. The aim of the current study was to assess nicotine exposure through smoking by measuring urinary cotinine, the major nicotine metabolite, in a group of smokers from Greece of smokers with schizophrenia and smokers from the general population. Participants were current smokers and belonged to one of two groups: 35 patients with schizophrenia and 48 healthy controls matched in age, education, and gender. The quantitative analysis of cotinine, the major metabolite of nicotine, in urine samples was performed by a modified high performance liquid chromatography (HPLC). Patients with schizophrenia who smoke presented a significantly larger time interval between last cigarette smoked and urine sample collection, as well as a significantly higher average number of cigarettes consumed daily than normal smokers. Urinary cotinine levels of patients with schizophrenia who smoke did not significantly differ from that of normal smokers when adjusted for average number of cigarettes per day and time interval between last cigarette smoked and urine collection. These results suggest that patients with schizophrenia did not present higher nicotine exposure through smoking compared with smokers from the community. The pharmacokinetic or pharmacodynamic properties of nicotine, as well as patient medications of the patients may explain our findings.

Adult↗
PubMed2004

Clock Drawing Test in patients with schizophrenia.

Investigations of the usefulness of the Clock Drawing Test (CDT) in schizophrenia have focused primarily on institutionalized or elderly patients. The purpose of the present study was to compare CDT performance of patients with schizophrenia living in the community with that of normal controls. Fifty-three patients with schizophrenia were compared with 66 age- and gender-matched normal controls. The CDT ('free-drawn', 'pre-drawn' and three 'examiner' conditions) and the Mini-Mental State Examination (MMSE) were administered to all participants. In patients with schizophrenia, symptom severity was assessed with the Positive and Negative Syndrome Scale (PANSS). Patients with schizophrenia had significantly lower scores on the MMSE and the five CDT conditions than the control group. When MMSE scores and level of education were included in the comparisons as covariates, the differences between the two groups remained significant. MMSE scores of the patients with schizophrenia correlated significantly with four clock conditions: 'free-drawn' 'pre-drawn' and two of the 'examiner' conditions (11:10 and 8:20). Poorer performance on the CDT correlated with higher scores on the PANSS positive symptoms subscale. Qualitative analysis of the clocks that were drawn revealed specific errors in the schizophrenia group relating to frontal processes: difficulty placing numbers in the correct position, failure to indicate the minute targets, displacement of the minute hand from the minute number, and failure to draw a longer minute hand. The fact that the CDT is sensitive enough to detect the cognitive impairment inherent in schizophrenia, as well as being correlated with symptom severity, makes this test useful in roughly assessing cognitive state in schizophrenia.

Activities of Daily Living↗
PubMed2004

Smoking impact on CYP1A2 activity in a group of patients with schizophrenia.

The purpose of the present study was to assess the impact of smoking on the metabolism of psychotropic drugs in a group of patients with schizophrenia, by measuring CYP1A2 activity. This activity was assessed by the molar ratio (MR) of caffeine metabolites in urine [(AFMU+1U+1X)/17U] and saliva (17X/137X). Participants were 40 patients with schizophrenia: 30 current cigarette smokers and 10 nonsmokers. The two groups (smokers and nonsmokers) differed significantly in their ratio of men to women (83% men and 17% women were among smokers compared with 50% men and 50% women nonsmokers). No other group differences were found regarding age, level of education, PANSS, extrapyramidal symptoms, age of symptoms onset, antipsychotic doses (chloropromazine equivalents), and anticholinergic drug used. Smokers had significant higher MR in urine (P<0.001) as well as in saliva (P=0.001) than nonsmokers, suggesting a higher activity of CYP1A2 dependent on smoking. When gender was used as a covariate, the differences between the two groups remained significant for MR. Cigarette smoking may be a factor influencing the plasma levels of antipsychotics that metabolized through CYP1A2. Clinicians should weight the possibility that smoking and the subsequent modulation of antipsychotic metabolism may be the main reason of treatment resistance. Furthermore, any attempt to reduce or cease smoking in patients with schizophrenia necessitates close monitoring of drug doses, because untoward adverse effects may emerge.

Adult↗
PubMed2004

Relationship of affect recognition with psychopathology and cognitive performance in schizophrenia.

The purpose of the present study was to explore the relationship between emotion perception and both psychopathology and cognitive functioning in a group of Greek patients with schizophrenia. Thirty-five patients with schizophrenia were assessed with computerized tests of emotion perception, using visual faces (Kinney's Affect Matching Test, KAMT), prosody (Affective Prosody Test, APT), and visual everyday scenarios (Fantie's Cartoon Test, FCT), as well as a facial recognition test (Kinney's Identity Matching Test, KIMT). The patients were also evaluated with the symptoms dimensions derived from the PANSS (positive, negative, cognitive, depression, and excitement) and a battery of neuropsychological tests measuring executive functions, attention, working memory, verbal and visual memory, visuospatial ability, and visual scanning/psychomotor speed. The three emotion perception and face recognition tests correlated significantly with each other. The KAMT was significantly related to the cognitive symptoms dimension of the PANSS and executive functions. The FCT was significantly related to level of education and attention. Finally, the APT was significantly related to the cognitive symptoms dimension, executive functions, and attention. Our findings regarding the significant relationships of affect perception, both facial and vocal, as well as in everyday scenarios, with several cognitive abilities support the notion that deficits in decoding affective information in schizophrenia could be attributed to impairment in more basic neurocognitive domains.

Adult↗
PubMed2004

Pellagra encephalopathy following B-complex vitamin treatment without niacin.

Pellagra is caused by nicotinic acid deficiency; it is rarely encountered in developed countries, and it is mainly related to poverty and malnutrition, as well as with chronic alcoholism. We report the case of an alcoholic patient who was diagnosed with pellagra and administered B-complex vitamin tablets that did not contain niacin. A few weeks later, the patient developed nervousness, irritability, insomnia and, consequently, delusional ideas and hallucinations, for which he had to be hospitalized. After his admission, the patient manifested loss of consciousness and myoclonus. All of his symptoms (cutaneous, neurological, and psychiatric) resolved fully with treatment with niacin in combination with other B-complex vitamins. All undiagnosed encephalopathies in alcoholic patients should be treated with multiple vitamin therapy, including nicotinic acid.

Adult↗
PubMed2003

Clock drawing test in institutionalized patients with schizophrenia compared with Alzheimer's disease patients.

The impaired performance of Alzheimer's disease (AD) patients on the clock drawing test (CDT) relative to age-matched normal controls is a well-documented finding in the literature. On the other hand, there is sparse information regarding the use of this test in schizophrenia. We examined three groups of subjects matched for gender and education: institutionalized patients with schizophrenia (n = 32), patients with AD (n = 32), and normal controls (n = 36). The CDT ("free-drawn", "pre-drawn", and three "examiner" conditions) and Mini-Mental State Examination (MMSE) were administered to all participants. In patients with schizophrenia, symptom severity was assessed with the Brief Psychiatric Rating Scale (BPRS). Patients with schizophrenia were significantly younger than AD patients and normal controls (56.78 versus 71.41 and 66.25, respectively), and normal controls had significantly higher MMSE scores than patients with schizophrenia and AD (27.58 versus 20.75 and 18.44, respectively). In all of the clock conditions, the two patient groups performed significantly poorer than the normal controls, with the exception of the "pre-drawn" clock in which AD patients also performed worse than patients with schizophrenia. Age and duration of illness did not correlate significantly with CDT scores. When MMSE scores were used as a covariate, all significant differences on the CDT among the three groups disappeared, with the exception of the "pre-drawn" clock (AD patients had lower scores than both control and schizophrenia groups). In patients with schizophrenia, scores on the BPRS were not related with any CDT variable. Institutionalized patients with schizophrenia and AD patients showed similar deficits on a neuropsychological test sensitive to changes in visual-analytic function, attention, receptive language, and executive functions such as planning, organization, and simultaneous processing.

Aged↗
PubMed2003

Familial bipolar disorder and multiple sclerosis: a three-generation HLA family study.

The coexistence of bipolar disorder (BD) and multiple sclerosis (MS) is well known. Manic symptoms may represent initial symptoms of MS, at least in some cases, and follow the MS-HLA phenotype frequencies. The purpose of this study was to examine the possible relation of BD and MS based on an HLA family study of a woman with BD and comorbid MS, with family history of BD. Five members of the family from three generations (the patient, her mother, her brother, and her two daughters) were examined regarding the two disorders and the HLA class I and II specificities, performed by serology and molecular techniques. Her deceased father, her brother, and her older daughter suffered from BD. Moreover, in her brother, BD and MS comorbidity was diagnosed. The three affected members and the nonaffected grandmother share the same class I and II, HLA-A2, B18, CW8, DR2, DQ1 haplotype. The shared class II, HLA-DR2, DQ1 haplotype among affected individuals, which is well known to be associated with MS in Caucasians, suggests a possible susceptibility locus for BD, mapped on chromosome 6, very close to the HLA region, underlying the clinical comorbidity of the two disorders.

Adult↗