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Alex Hofer

Publications and source records attributed to Alex Hofer.

29 records · Page 2Linked to original sources

Brain activation patterns during a verbal fluency test-a functional MRI study in healthy volunteers and patients with schizophrenia.

FMRI was used to study cortical activation patterns in nine healthy male subjects and nine high-functioning male schizophrenia patients during a letter verbal fluency task. Both groups showed similar patterns of activation, however, in controls the activation was primarily in the left broca area, while for schizophrenia patients, it was more bilateral. These data indicate that high-functioning schizophrenia patients show a reduced language lateralization of the frontal cortex compared to healthy controls.

Adult↗

Compliance in schizophrenia: psychopathology, side effects, and patients' attitudes toward the illness and medication.

OBJECTIVE: In a cross-sectional study, we investigated the influence of several factors on compliance in schizophrenia outpatients, including patients' attitudes toward the illness and medication, specifically antipsychotic medication; adverse effects; and attitudes of caregivers and relatives toward the illness and medication. METHOD: Patients suffering from schizophrenia (ICD-10 diagnosis) of at least 1-year's duration whose discharge from an inpatient ward was at least 6 weeks prior to inclusion in the study were investigated. Study instruments included a semi-structured compliance interview, the Positive and Negative Syndrome Scale, the Udvalg for Klinske Undersogelser Side Effect Rating Scale, the St. Hans Rating Scale, and the Hillside Akathisia Scale. Data were collected from May 1998 to December 2001. RESULTS: 52.5% (N = 32) of the 61 investigated patients were fully compliant, 39.3% (N = 24) were partially compliant, and only 8.2% (N = 5) were noncompliant. We found positive correlations between compliance and the patients' feelings of a positive effect of the drug on the illness, between compliance and negative symptoms, and between compliance and antipsychotic-induced psychological side effects. CONCLUSION: Our findings reemphasize the importance of taking subjective attitudes and concerns of patients with respect to their illness and medication seriously. Therefore, it is indispensable to include patients and, if possible, their relatives in the treatment decision process to enhance medication compliance in schizophrenia patients.

Adult↗

Quality of life in schizophrenia: the impact of psychopathology, attitude toward medication, and side effects.

BACKGROUND: Quality of life (QOL) is now seen as a key outcome variable in schizophrenia. Factors deemed relevant in this context include severity of symptoms, antipsychotic-induced side effects, sociodemographic variables, and patients' subjective response to medication. METHOD: In the current cross-sectional study, 80 patients with a schizophrenic disorder according to ICD-10 criteria who had a duration of illness over 1 year and whose discharge from an inpatient unit had been at least 6 weeks earlier were investigated. Apart from the registration of demographic data, various rating scales were used: the Positive and Negative Syndrome Scale (PANSS), the St. Hans Rating Scale for Extrapy-ramidal Syndromes, the UKU Side Effect Rating Scale, the Drug Attitude Inventory, and the Lancashire Quality of Life Profile. RESULTS: More than half of all patients (47/80) indicated that they were satisfied with their life in general. The specific areas of subjective dissatisfaction that were most commonly noted in the present sample concerned partnership and mental health. The depression/anxiety component of the PANSS, parkinsonism, and a negative attitude toward antipsychotic medication negatively influenced the patients' QOL, while cognitive symptoms and employment status correlated with higher QOL. CONCLUSION: Our results highlight the importance of recognizing the complex nature of QOL in schizophrenia patients. They suggest that special attention should be paid to patients who experience anxiety and depressive symptoms or parkinsonism, to those who are unemployed, and to those with negative feelings and attitudes toward antipsychotics.

Antipsychotic Agents↗

Brain activation patterns during a selective attention test-a functional MRI study in healthy volunteers and patients with schizophrenia.

Functional magnetic resonance imaging was used to compare cortical activation patterns in healthy volunteers with those in patients with schizophrenia during a modified verbal Stroop task. Healthy subjects (n=13) and patients with schizophrenia (n=13) on stable antipsychotic treatment, matched on demographic variables, were included. Patients were preselected on the basis of good performance on a selective attention test. Patients with schizophrenia showed a significantly increased pattern of activation in the left and right inferior frontal cortex and the anterior cingulate cortex. A significant negative correlation between activation of the left prefrontal cortex and accuracy in the modified Stroop test was observed for healthy controls but not schizophrenia patients. Although both groups recruited the prefrontal cortex during the modified Stroop task, for the schizophrenia patients this activation was bilateral, whereas for the controls this activation was primarily in the left hemisphere, suggesting that patients with schizophrenia recruited more prefrontal regions to perform the task with the same accuracy as healthy controls. Our findings of increased activity across multiple areas of the brain, including dorsolateral frontal cortex and anterior cingulate, in patients with schizophrenia who perform relatively well on a task of selective attention give further evidence that task performance may be a confounding factor in the interpretation of neuroimaging results.

Adult↗

The safety of clozapine in the treatment of first- and multiple-episode patients with treatment-resistant schizophrenia.

The importance of antipsychotics in the treatment of schizophrenia has been documented in numerous clinical trials. In addition to its established superiority over other antipsychotics in treatment-resistant patients, clozapine has been consistently shown to improve psychopathology and other psychosocial outcome variables in patients with schizophrenia. To determine whether the course of the illness has an influence on response and side-effects to clozapine, we directly contrasted first- and multiple-episode patients with schizophrenia, who had histories of failing response to traditional antipsychotics, during the acute treatment phase. Thirty-nine first-episode patients with schizophrenia and 56 patients who had suffered from at least two episodes of this illness were investigated. Severity of illness and clinical improvement were rated by means of the CGI Scale. Vital signs were recorded weekly. Side-effects were regularly assessed with the UKU Side Effect Rating Scale. Compliance was regularly assessed by clinical interviews and plasma level monitoring. By using comparable mean clozapine doses, the number of treatment responders was similar in both groups (first-episode patients, 51.3%; multiple-episode patients, 46.4%). However, we found a negative association between age and response rate. With regard to side-effects, we could not find any significant difference between groups. Altogether, response and side-effects to clozapine treatment do not seem to be determined by the chronicity of the disorder.

Adult↗

Neural correlates of episodic encoding and recognition of words in unmedicated patients during an acute episode of schizophrenia: a functional MRI study.

OBJECTIVE: Memory impairment has been well documented in schizophrenia. In a previous study, the authors investigated patterns of brain activity during episodic encoding and recognition of words in remitted, stable schizophrenia outpatients being treated with novel antipsychotics. The same procedure was used in this study to investigate unmedicated patients during an acute episode of schizophrenia. METHOD: Functional magnetic resonance imaging was used to study regional brain activation in 10 unmedicated patients experiencing an acute episode of schizophrenia and 10 healthy comparison subjects during performance of a modified version of the words subtest of Warrington's Recognition Memory Test. RESULTS: Despite intact recognition performance, patients with schizophrenia showed reduced activation of anterior prefrontal, posterior cingulate, and retrosplenial areas relative to comparison subjects during word encoding. During word recognition, reduced activation was found in the patients' dorsolateral prefrontal and limbic/paralimbic regions. On the other hand, higher metabolism in bilateral anterior prefrontal cortices was observed. CONCLUSIONS: The results suggest that different neural pathways are engaged during episodic encoding and recognition of words in patients experiencing an acute episode of schizophrenia relative to healthy comparison subjects. Furthermore, acute psychosis may prevent practice effects, reflected in a failure to engage brain regions associated with successful episodic memory retrieval in healthy subjects.

Acute Disease↗

An FMRI study of episodic encoding and recognition of words in patients with schizophrenia in remission.

OBJECTIVE: Verbal memory deficits are among the most severe cognitive deficits observed in patients with schizophrenia. This study examined patterns of brain activity during episodic encoding and recognition of words in patients with schizophrenia. METHOD: Functional magnetic resonance imaging (fMRI) was used to study regional brain activation in 10 healthy male comparison subjects and 10 male outpatients with schizophrenia during performance of a modified version of the words subtest of Warrington's Recognition Memory Test. RESULTS: Despite having intact performance in word recognition, the patients with schizophrenia had less activation of the right dorsolateral and anterior prefrontal cortex, right anterior cingulate, and left lateral temporal cortex during word encoding, compared with the healthy comparison subjects. During word recognition, the patients had impairments in activation of the bilateral dorsolateral prefrontal and lateral temporal cortices. CONCLUSIONS: Schizophrenia was associated with attenuated frontotemporal activation during episodic encoding and recognition of words. These results from an fMRI study replicate earlier findings derived from a positron emission tomography study.

Adult↗

Attitudes of patients with schizophrenia toward placebo-controlled clinical trials.

BACKGROUND: Despite the fact that the efficacy of antipsychotic treatment in patients with schizophrenia has been demonstrated in numerous double-blind studies, placebo-controlled studies are still commonly performed. Although much is known about the opinions of professionals concerning this issue, so far nothing is known about the opinions of patients who are most affected by the realization of placebo-controlled clinical trials. METHOD: In a cross-sectional study from June 2000 to January 2001, 100 inpatients and outpatients with ICD-10 schizophrenia or schizophreniform disorder were investigated by using a questionnaire specifically developed to survey patients' attitudes concerning possible participation in placebo-controlled clinical trials. Psychopathology and side effects were physician-rated. RESULTS: 56% of patients would not be willing to participate in a placebo-controlled clinical trial. On the other hand, only about 16% of the patients are against clinical trials in principle. Gender, treatment, severity of psychopathology (Positive and Negative Syndrome Scale), adverse events (UKU Side Effect Rating Scale), and attitude toward medication (Drug Attitude Inventory) had no statistically significant influence on the decision. Most of the patients (76%) stated that they would not lose trust in their physician if asked to participate in a placebo-controlled clinical trial. CONCLUSION: The opinions and fears of patients who are most affected by the debate need to be considered when deciding whether a placebo-controlled clinical trial is necessary.

Adult↗

Olanzapine induces insulin resistance: results from a prospective study.

BACKGROUND: The aim of this study was to compare glucose metabolism in patients with schizophrenia receiving olanzapine with that in control subjects. METHOD: We conducted a prospective, controlled, open study comparing body weight, fat mass, and indices of insulin resistance/ sensitivity in 10 olanzapine-treated patients with ICD-10 schizophrenia (olanzapine dose range, 7.5-20 mg/day) with those of a group of 10 mentally and physically healthy volunteers. Weight, fat mass, and indices of insulin resistance/sensitivity were assessed over individual 8-week observation periods from November 1997 to October 1999. RESULTS: Fasting serum glucose and fasting serum insulin increased significantly in the olanzapine-treated patients (p =.008 for glucose and p =.006 for insulin). The homeostasis model assessment (HOMA) index for beta cell function did not change significantly in the olanzapine-treated patients, whereas the HOMA index for insulin resistance did increase (p =.006). In the control group, these parameters were stable. A significant increase in body weight (p =.001) and body fat (p =.004) was seen in patients treated with olanzapine, while the control group showed no significant changes. CONCLUSION: This study indicates that the disturbances in glucose homeostasis during antipsychotic treatment with olanzapine are mainly due to insulin resistance. However, beta cell function remains unaltered in olanzapine-treated patients. We conclude that treatment with some second-generation antipsychotic drugs may lead to insulin resistance.

Adult↗

Attitudes toward antipsychotics among outpatient clinic attendees with schizophrenia.

BACKGROUND: A cross-sectional study was conducted in patients with schizophrenia who regularly attended an outpatient clinic to examine the impact of psychopathology, side effects, and sociodemographic factors on attitudes toward antipsychotics. METHOD: Sixty patients with a schizophrenic disorder according to ICD-10 criteria who had a duration of illness over 1 year and whose discharge from an inpatient unit had been at least 6 weeks earlier were investigated. Apart from the registration of demographic data, various rating scales were used: the Positive and Negative Syndrome Scale, the St. Hans Rating Scale for Extrapyramidal Syndromes, the Udvalg for Kliniske Undersogelser (UKU) Side Effect Rating Scale, and the Drug Attitude Inventory (DAI). RESULTS: Generally, the aspects describing a positive attitude toward antipsychotics on the DAI received a higher degree of assent than those characterizing a negative drug attitude. However, employment status correlated with a poorer global medication attitude on the DAI, and positive symptoms and sedation correlated with greater negative feelings on the DAI subjective negative feelings subscale. CONCLUSION: Our results suggest that special attention should be paid to patients who experience positive symptoms or sedation and to those with relative absence of symptoms, who are therefore tempted to stop taking medication.

Adult↗