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Cyril Höschl

Publications and source records attributed to Cyril Höschl.

11 recordsLinked to original sources

Changes in QEEG prefrontal cordance as a predictor of response to antidepressants in patients with treatment resistant depressive disorder: a pilot study.

INTRODUCTION: Previous studies of patients with unipolar depression have shown that early decreases of EEG cordance (a new quantitative EEG method) can predict clinical response. We examined whether early QEEG decrease represents a phenomenon associated with response to treatment with different antidepressants in patients with treatment resistant depression. METHOD: The subjects were 17 inpatients with treatment resistant depression. EEG data and response to treatment were monitored at baseline and after 1 and 4 weeks on an antidepressant treatment. QEEG cordance was computed at three frontal electrodes in theta frequency band. The prefrontal cordance combines complementary information from absolute and relative power of EEG spectra. Recent studies have shown that cordance correlates with cortical perfusion. Depressive symptoms were assessed using Montgomery-Asberg Depression Rating Scale (MADRS). RESULTS: All 17 patients completed the 4-week study. All five responders showed decreases in prefrontal cordance after the first week of treatment. Only 2 of the 12 nonresponders showed early prefrontal cordance decrease. The decrease of prefrontal QEEG cordance after week 1 in responders as well as the increase in nonresponders were both statistically significant (p-value 0.03 and 0.01, respectively) and the changes of prefrontal cordance values were different between both groups (p-value 0.001). CONCLUSION: Our results suggest that decrease in prefrontal cordance may indicate early changes of prefrontal activity in responders to antidepressants. QEEG cordance may become a useful tool in the prediction of response to antidepressants.

Adult↗

Prospective study of hippocampal volume and function in human subjects treated with corticosteroids.

PURPOSE: Decreased hippocampal volume reported in neuropsychiatric and endocrine disorders is considered a result of putative neuronal damage mediated by corticosteroids. This is the first prospective study of hippocampal volume and function in patients treated with corticosteroids. METHODS: 14 subjects treated systemically with prednisone or betamethasone for dermatological or rheumatic disorders underwent prospective neurocognitive testing (Auditory Verbal Learning Test-AVLT, Trail Making Test-TMT, Digit Span-DS) and nine of them also repeated magnetic resonance volumetry. RESULTS: The mean duration of treatment between the first and the second assessment was 73+/- 38 days with mean daily dose of 37+/- 17 mg prednisone and 193+/- 29 days, with mean daily dose of 24+/- 15 mg prednisone between the first and the third assessment. There was a trend towards decreases in total AVLT scores and an improvement in the TMT and DS, but no significant changes in the volumes of the right or the left hippocampi between the assessments. Prednisone dose did not correlate with the hippocampal volume change. CONCLUSION: We observed a trend for decline in verbal memory despite improvement in psychomotor speed, attention/working memory and no macroscopic hippocampal volume changes during 36-238 days of treatment with therapeutic doses of corticosteroids.

Adult↗

Mechanism of action of atypical antipsychotic drugs and the neurobiology of schizophrenia.

Atypical antipsychotics have greatly enhanced the treatment of schizophrenia. The mechanisms underlying the effectiveness and adverse effects of these drugs are, to date, not sufficiently explained. This article summarises the hypothetical mechanisms of action of atypical antipsychotics with respect to the neurobiology of schizophrenia.When considering treatment models for schizophrenia, the role of dopamine receptor blockade and modulation remains dominant. The optimal occupancy of dopamine D(2) receptors seems to be crucial to balancing efficacy and adverse effects - transient D(2) receptor antagonism (such as that attained with, for example, quetiapine and clozapine) is sufficient to obtain an antipsychotic effect, while permanent D(2) receptor antagonism (as is caused by conventional antipsychotics) increases the risk of adverse effects such as extrapyramidal symptoms. Partial D(2) receptor agonism (induced by aripiprazole) offers the possibility of maintaining optimal blockade and function of D(2) receptors. Balancing presynaptic and postsynaptic D(2) receptor antagonism (e.g. induced by amisulpride) is another mechanism that can, through increased release of endogenous dopamine in the striatum, protect against excessive blockade of D(2) receptors. Serotonergic modulation is associated with a beneficial increase in striatal dopamine release. Effects on the negative and cognitive symptoms of schizophrenia relate to dopamine release in the prefrontal cortex; this can be modulated by combined D(2) and serotonin 5-HT(2A) receptor antagonism (e.g. by olanzapine and risperidone), partial D(2) receptor antagonism or the preferential blockade of inhibitory dopamine autoreceptors. In the context of the neurodevelopmental disconnection hypothesis of schizophrenia, atypical antipsychotics (in contrast to conventional antipsychotics) induce neuronal plasticity and synaptic remodelling, not only in the striatum but also in other brain areas such as the prefrontal cortex and hippocampus. This mechanism may normalise glutamatergic dysfunction and structural abnormalities and affect the core pathophysiological substrates for schizophrenia.

Animals↗

Moclobemide and cognitive behavioral therapy in the treatment of social phobia. A six-month controlled study and 24 months follow up.

The aim of the study was to assess the 6-months treatment efficacy and 24-month follow up of three different therapeutic programs (A. moclobemide and supportive guidance, B. group cognitive-behavioral therapy and pill placebo, and C. combination of moclobemide and group cognitive-behavioral therapy) in patients with a generalized form of social phobia. Eighty one patients (38 males and 43 females) were randomly assigned to three different therapeutic programs. Patients were regularly assessed on a monthly basis by an independent rater on the LSAS (Liebowitz Social Anxiety scale), CGI (Clinical Global Impression) for severity and change and BAI (Beck Anxiety Inventory). Altogether, sixty-six patients completed the six month treatment period and 15 patients dropped out. All therapeutic groups showed significant improvement. A combination of CBT and pharmacotherapy yielded the most rapid effect. Moclobemide was superior for the reduction of the subjective general anxiety (BAI) during the first 3 months of treatment, but its influence on avoidant behavior (LSAS avoidance subscale) was less pronounced. Conversely, CBT was the best choice for reduction of avoidant behavior while a reduction of subjective general anxiety appeared later than in moclobemide. After 6 months of treatment there were best results reached in groups treated with CBT and there was no advantage of the combined treatment. The relapse rate during the 24-month follow up was significantly lower in the group treated with CBT in comparison with the group A. formerly treated with moclobemide alone.

Adolescent↗

Regional brain metabolism as the predictor of performance on the Trail Making Test in schizophrenia. A 18FDG PET covariation study.

OBJECTIVES: With the aim to indicate the functional anatomical substrate of cognitive dysfunction in schizophrenia we evaluated the relationship between resting brain metabolism and performance on the Trail Making Test (TMT). As the prerequisite analysis we compared the performance in Part A and B of the TMT between schizophrenic patients and controls. Resting brain metabolism was investigated by (18)FDG positron emission tomography (PET) as the probe for the relative regional synaptic strength and density. METHODS: (18)FDG PET data were analyzed by SPM99 with TMT A and B as the covariate (p< or =0.001). RESULTS: Schizophrenic patients (N=42) had worse performance in both TMT A and B compared to controls (N=42). In schizophrenic subjects (18)FDG PET did not predict the performance on Part A (psychomotor speed) but predicted that for Part B (set-shifting and flexibility) of the TMT. The (18)FDG uptake in the superior, middle and inferior frontal gyruses bilaterally was associated with better performance in the TMT B. The negative covariation between 18FDG uptake and time spent in the TMT B was detected in the temporal and parietal cortices, pre- and postcentral gyruses, precuneus limbic regions (anterior cingulate, uncus) and the pons. CONCLUSIONS: Our data indicate that hypometabolism in the frontal lobes and hypermetabolism in the temporo-parieto-limbic regions is the neurobiological basis for deficient TMT B performance in schizophrenia.

Adolescent↗

Magnetic resonance relaxometry in monozygotic twins discordant and concordant for schizophrenia.

T1 and T2 relaxation times were examined in four pairs of monozygotic (MZ) twins discordant and concordant for schizophrenia with low and high genetic loading for the illness and five healthy control MZ twin pairs. Patients with schizophrenia (n = 11) showed significant prolongation in T1 relaxation times in the globus pallidus (GP) bilaterally (P < 0.005, Bonferroni corrected) when compared to 14 healthy MZ twins.

Adult↗

The effect of tryptophan depletion on the action of haloperidol in MK-801-treated rats.

We investigated the effect of tryptophan depletion (tryptophan-free mixture) on locomotor activity in an animal model of schizophrenia, induced by acute administration of 5R,10S-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]-cyclohepten-5,10-imine hydrogen maleate (MK-801), and the influence of the tryptophan-free mixture on the action of the typical antipsychotic haloperidol. Male rats were pre-treated with haloperidol 60 min after receiving the tryptophan-free mixture (or water). We measured total distance travelled in an open field during a 90-min period. Administration of the tryptophan-free mixture resulted in decreased levels of tryptophan, serotonin and its metabolite 5-hydroxyindolacetic acid in the frontal cortex. Serotonin depletion increased the total distance travelled by MK-801-treated rats, modified the inhibitory effect of haloperidol and normalized the locomotor activity pattern in the model of schizophrenia-like behaviour. The effect of the tryptophan-free mixture combined with the classical antipsychotic haloperidol in MK-801-treated rats indicates the possibly important role of the serotonergic system in the action of antipsychotics.

Animals↗

The change of regional brain metabolism (18FDG PET) in panic disorder during the treatment with cognitive behavioral therapy or antidepressants.

BACKGROUND: The goal of our study was to identify brain structures in patients with panic disorder (PD) that show changes in 18FDG PET during the treatment with cognitive behavioral therapy (CBT) or antidepressants. METHOD: Twelve patients suffering from panic disorder were studied with [18F]-2-fluoro-deoxyglucose positron emission tomography (18FDG PET) scanning during resting state (condition of random episodic silent thinking, REST). After PET examination patients were randomly assigned to either cognitive behavioral treatment group (6 patients) or antidepressants treatment group (6 patients). After a 3 month period 18FDG PET examination was repeated in both groups. Psychopathology was assessed using the rating scales HAMA, CGI and Panic Disorder Severity Scale (PDSS). Data were analysed using software for statistical parametric mapping (SPM99). RESULTS: The scores of psychopathology rating scales (CGI, HAMA, PDSS) decreased in both groups. Changes of 18FDG uptake in the pharmacotherapy group: decreases were found in the a priori hypothesized regions in the right hemisphere, in the superior, middle, medial and inferior frontal gyrus, superior and middle temporal gyrus, and increases were detected in the a priori hypothesized regions, mainly in the left hemisphere in medial and middle frontal gyrus, superior, middle and transverse temporal gyrus. Changes of 18FDG uptake in the CBT group: decreases were found in the a priori hypothesized regions of the right hemisphere in the inferior temporal gyrus, superior and inferior frontal gyrus, and increases were detected in the a priori hypothesized region, mostly in the left hemisphere: inferior frontal gyrus, middle temporal gyrus and insula. We did not detect changes in 18FDG uptake in the limbic region (hippocampus, parahippocampal gyrus and amygdala). CONCLUSIONS: Changes in brain metabolism (18FDG uptake) after the treatment either with CBT or with antidepressants were similar in number of brain areas, with prominent right-left difference. This is in concordance with the asymmetry of brain activity noted in patients with PD according to previous PET (and SPECT) studies.

Adult↗

Higher prevalence of antibodies to Borrelia burgdorferi in psychiatric patients than in healthy subjects.

OBJECTIVE: Borrelia burgdorferi infection can affect the CNS and mimic psychiatric disorders. It is not known whether Borrelia burgdorferi contributes to overall psychiatric morbidity. The authors compared the prevalence of antibodies to Borrelia burgdorferi in groups of psychiatric patients and healthy subjects to find out whether there is an association between this infection and psychiatric morbidity. METHOD: Between 1995 and 1999 the authors screened for antibodies to Borrelia burgdorferi in 926 psychiatric patients consecutively admitted to Prague Psychiatric Center. They compared the results of this screening with findings from 884 consecutive healthy subjects who took part in an epidemiological survey of antibodies to Borrelia burgdorferi in the general population of the Czech Republic. Sera were tested by means of enzyme-linked immunosorbent assay. Circulating immune complexes were isolated by polyethylene glycol precipitation. To control for potential confounders, the two groups of patients and healthy subjects were matched according to gender and age. Results were obtained in a sample of 499 matched pairs. RESULTS: Among the matched pairs, 166 (33%) of the psychiatric patients and 94 (19%) of the healthy comparison subjects were seropositive in at least one of the four assays. CONCLUSIONS: These findings support the hypothesis that there is an association between Borrelia burgdorferi infection and psychiatric morbidity. In countries where this infection is endemic, a proportion of psychiatric inpatients may be suffering from neuropathogenic effects of Borrelia burgdorferi.

Adolescent↗

The double-blind sham-controlled study of high-frequency rTMS (20 Hz) for negative symptoms in schizophrenia: negative results.

The high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) over the prefrontal cortex is a promising method for the treatment of negative symptoms of schizophrenia. Using double-blind sham-controlled parallel design, we evaluated the effect of HF-rTMS over the left dorsolateral prefrontal cortex (DLPFC) on negative symptoms in patients with schizophrenia. Sixteen schizophrenia patients with predominantly negative symptoms on stable antipsychotic medication were treated with 20 Hz rTMS (90% of motor threshold, 2000 stimuli per session) over ten days within 2 weeks with six weeks follow-up. The effect was assessed using PANSS, CGI, MADRS and neuropsychological tests. We failed to find any significant effect of active rTMS. Sham rTMS showed a trend for improvement over time on positive and negative subscales of PANSS and MADRS. Between-group comparisons failed to reveal any significant differences on any rating scales except a positive subscale of PANSS after 8 weeks. Results from our study did not confirm that HF-rTMS over the left DLPCF affects the negative symptoms of schizophrenia and alternative rTMS approaches are discussed.

Adult↗