Biomedical subjects

Michael Zaudig

Publications and source records attributed to Michael Zaudig.

13 recordsLinked to original sources

PubMed2006

Mild cognitive impairment.

Mild cognitive impairment is a syndrome defined as cognitive decline greater than expected for an individual's age and education level but that does not interfere notably with activities of daily life. Prevalence in population-based epidemiological studies ranges from 3% to 19% in adults older than 65 years. Some people with mild cognitive impairment seem to remain stable or return to normal over time, but more than half progress to dementia within 5 years. Mild cognitive impairment can thus be regarded as a risk state for dementia, and its identification could lead to secondary prevention by controlling risk factors such as systolic hypertension. The amnestic subtype of mild cognitive impairment has a high risk of progression to Alzheimer's disease, and it could constitute a prodromal stage of this disorder. Other definitions and subtypes of mild cognitive impairment need to be studied as potential prodromes of Alzheimer's disease and other types of dementia.

Aged↗

PubMed2006

Symptom-specific EEG power correlations in patients with obsessive-compulsive disorder.

Neurophysiological studies in patients with obsessive-compulsive disorder (OCD) consistently revealed frontal alterations of cortical activity but otherwise showed inhomogeneous results, conceivably due to variable subgroups with diverse pathomechanisms involved. The aim of this study was to investigate quantitative electroencephalography (EEG) in patients with OCD as compared to healthy controls and to correlate neurophysiological data with clinical variables. EEGs were digitally recorded from 18 unmedicated patients (8 male, mean age 32.4+/-11.8 years, Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) 15.3+/-7.9) and 18 matched healthy controls, and analysed quantitatively. The mean frequency of EEG background activity and absolute power in delta, theta, alpha and beta frequency bands were calculated. Mean frequency of background activity was significantly lower in patients as compared to controls (-1.44/s, p<0.01), predominantly for the frontal electrode positions. Power spectra revealed increased delta- and decreased alpha-/beta-power in the group of patients (p<0.05, patients vs. controls). Correlation analyses showed significant positive correlations of EEG-power with the Y-BOCS sub-scores "obsessions", and negative correlations with the sub-scores "compulsions" (Spearman's correlations, r(s)=+0.48 to +0.70, and -0.47 to -0.6, respectively, p<0.05). The data provide evidence of a dysfunction of frontal cortical activity in patients with OCD. The opposite correlations of neurophysiological data and clinical features, i.e. obsessions and compulsions, are suggestive of pathophysiological differences based on the presence of the respective cardinal symptoms of OCD.

Adolescent↗

PubMed2005

Impairment of pain inhibition in chronic tension-type headache.

Evidence has been accumulated suggesting that a dysfunction in pain inhibitory systems, i.e. in 'diffuse noxious inhibitory controls' (DNIC)-like mechanisms, might be-amongst other factors-responsible for the development of anatomically generalized chronic pain like fibromyalgia. The aim of the present study was to look for similar impairments in chronic tension-type headache (CTTH) as a regionally specific pain syndrome. Twenty-nine CTTH patients and 25 age- and sex-matched healthy control subjects participated in the study. After baseline assessment of electrical detection and pain thresholds, tonic heat stimuli were concurrently applied by a thermode to the thigh to induce DNIC-like pain inhibition. Tonic heat stimuli were applied either slightly above ('pain' condition) or slightly below ('heat' condition) pain threshold. For determination of electrical detection and pain thresholds, electrocutaneous stimuli were administered either to the forearm (extra-cranial site) or to the temple (cranial site), using a multiple staircase procedure. The increase in the electrical detection and pain thresholds induced by concurrent tonic heat stimulation was significantly smaller in the CTTH patients than in the control subjects. This group difference was present during the 'pain' as well as the 'heat' condition. Furthermore, the electrical detection and pain thresholds were affected in this group-specific manner both at the forearm and at the temple. These findings suggest that patients with CTTH suffer from deficient DNIC-like pain inhibitory mechanisms in a similar manner, as do patients with anatomically generalized chronic pain like fibromyalgia.

Adult↗

PubMed2005

Implicit sequence learning in obsessive-compulsive disorder: further support for the fronto-striatal dysfunction model.

BACKGROUND: Obsessive-compulsive disorder (OCD) is conceived as a disease that implicates dysfunctions in fronto-striatal brain systems. According to this model, performance deficits observed in patients with lesions in these brain areas are hypothesized to be present also in OCD patients. Implicit procedural learning, which refers to the acquisition of motor or nonmotor skills by practice, is one candidate function to test this prediction. METHODS: The serial reaction time task was used to assess implicit sequence learning of 33 patients with a diagnosis of OCD and 27 healthy control participants. In addition, explicit (i.e., conscious) knowledge of the sequence was determined. A subgroup of 24 patients was reassessed after intensive cognitive-behavioral psychotherapy. RESULTS: Implicit sequence learning was significantly reduced in the OCD group by 41%, while explicit learning and verbal abilities were unaffected. The deficit remained stable across time, although symptoms remitted substantially. Depressive symptoms did not account for the finding. Partial explicit knowledge of the sequence was not a predictor of the amount of implicit learning. CONCLUSIONS: Reduced implicit learning appears to be a dissociable trait of OCD patients. The results confirm previous findings and add supportive evidence for the fronto-striatal dysfunction model of OCD.

Adult↗

PubMed2005

Can a subgroup of OCD patients with motor abnormalities and poor therapeutic response be identified?

RATIONALE: In a subgroup of patients with obsessive-compulsive disorder (OCD), motor soft signs, tics and other movement disorders can be observed, indicating a special pathogenetic involvement of basal ganglia. OBJECTIVES: The main objective of this study was to verify the hypothesis that such motor dysfunction characterises a subgroup of OCD patients with poor treatment response. For assessing even subtle motor dysfunction, a new method for kinematical analysis of hand movements has been applied. METHODS: We examined the performance of 45 in-patients who met the DSM-IV criteria for OCD before and under therapy (sertraline and behaviour therapy) using a digitising tablet and kinematical analysis of simple handwriting and drawing movements. All subjects wrote a sentence, their signature and letter sequences. Moreover, they drew circles under different conditions. Three kinematical parameters (stroke duration, variation coefficient of peak velocity, stroke length) were calculated to quantify hand-motor performance. RESULTS: Prior to therapy, non-responders wrote with significantly smaller amplitudes than responders. Additionally, non-responders drew significantly larger circles with the non-dominant hand at baseline, as compared to responders. Disturbances of handwriting were more frequent in non-responders than in responders. CONCLUSIONS: Kinematical analysis of handwriting movements seems to be interesting for the prediction of poor response to treatments in OCD patients.

Adult↗

PubMed2004

Serotonin and dopamine transporter availabilities correlate with the loudness dependence of auditory evoked potentials in patients with obsessive-compulsive disorder.

Brain monoaminergic function is involved in the pathophysiology of psychiatric disorders. The loudness dependence (LD) of the N1/P2 component of auditory evoked potentials has been proposed as a noninvasive indicator of central serotonergic function, whereas single photon emission computed tomography (SPECT) and [123I]beta-CIT can be used to visualize both serotonin (SERT) and dopamine transporters (DAT). The aim of the study was to correlate LD and SPECT measures in patients with obsessive-compulsive disorder, a condition with evidence for a serotonergic dysfunction. A total of 10 subjects received both neurophysiological and imaging investigations. Evoked potentials were recorded following the application of acoustic stimuli with increasing intensities. The LD of the relevant subcomponents (tangential dipoles) was investigated using dipole source analysis. SPECT was performed 20-24 h after injection of a mean 140 MBq [123I]beta-CIT. As a measure of brain SERT and DAT availabilities, a ratio of specific to nonspecific [123I]beta-CIT binding for the midbrain . pons region (SERT) and the striatum (DAT) was used. The LD of the right tangential dipole correlated significantly with both SERT and DAT availabilities (Pearson's correlations: rho = 0.69, p < 0.05, and rho = 0.80, p < 0.01, respectively). The correlations remained significant after controlling for the effects of age, gender, and severity of clinical symptoms. Associations between LD and both SERT and DAT availabilities further validate the use of neurophysiological approaches as noninvasive indirect measures of neurochemical brain function and point at a hypothesized interconnection of central monoaminergic systems.

Acoustic Stimulation↗

PubMed2004

[Fifty years of psychosomatic inpatient treatment].

This article is a review of the historical development of psychosomatic inpatient treatment form its first roots to present. The major focus of the article is a description of the present situation of psychosomatic hospitals in Germany, the kind of inpatient treatment in psychosomatic medicine, current concepts, data on lengths of stay, comorbidity, and the spectrum of diagnoses concerning psychosomatic inpatients. Furthermore, data on effectiveness of inpatient treatment and a description of a typical patient sample in psychosomatic inpatient treatment are outlined.

History, 19th Century↗

PubMed2003

Elevated brain serotonin transporter availability in patients with obsessive-compulsive disorder.

BACKGROUND: A central serotonergic dysfunction is considered to be involved in the pathophysiology of obsessive-compulsive disorder (OCD). The aim of this study was to investigate the serotonin transporter availability in patients with OCD as an in vivo marker of the central serotonergic system. METHODS: Nine unmedicated (7 drug-naive) patients with OCD and 10 healthy control subjects were included and received single photon emission computed tomography (SPECT) 20.75 +/- 1.51 hours after injection of a mean 147.20 +/- 6.74 MBq [(123)I]-2beta-carbomethoxy-3beta-(4-iodophenyl)tropane ([(123)I]beta-CIT). As a measure of brain serotonin transporter availability, a ratio of specific-to-nonspecific [(123)I]beta-CIT binding for the midbrain-pons (V(3)" = [midbrain/pons-occipital]/occipital) was used. RESULTS: Mean specific-to-nonspecific ratios showed a 25% higher midbrain-pons [(123)I]beta-CIT binding in the patients as compared with healthy controls (2.26 +/-.37 vs. 1.81 +/-.23, p <.01). The difference remained significant after adjustment for clinical variables and controlling for age and gender. Stratification of the patients according to onset of the disorder revealed significant differences between controls and patients with early (childhood, adolescence) but not late (adult) onset of OCD. CONCLUSIONS: The study provides evidence of a serotonergic dysfunction in patients with OCD and suggests a serotonergic component in the pathophysiology of the disorder.

Adult↗

PubMed2003

Effects of sertraline on kinematic aspects of hand movements in patients with obsessive-compulsive disorder.

RATIONALE: Movement disorders such as disturbances of fine motor co-ordination are a frequent phenomenon in patients with obsessive-compulsive disorder (OCD). OBJECTIVES: Our aim was to investigate changes of hand-motor dysfunction in OCD patients under the influence of 10-week treatment with sertraline and behaviour therapy. METHODS: We examined the performance of 40 patients satisfying DSM-IV criteria for OCD before and under this therapy using a digitising tablet and kinematic analysis of handwriting and drawing movements. Forty healthy controls were also tested (test-retest interval: 10 weeks). RESULTS: The speed of drawing was significantly lower in OCD patients than in controls (mean+/-standard deviation=197.03+/-113.26 mm/s for patients and 182.48+/-189.61 mm/s for controls; P=0.01). After 10 weeks of therapy, this parameter normalised in patients (from 197.03+/-113.26 mm/s to 163.66+/-101.92 mm/s; P=0.001). CONCLUSIONS: Hand-motor dysfunction (especially bradykinesia) improves with a serotonin-enhancing therapy in OCD patients.

Adult↗

PubMed2002

Mild cognitive impairment in older people.

CONTEXT: As public awareness of Alzheimer's disease increases, more people are asking for help and advice about memory problems. Memory complaints may be secondary to psychiatric, psychological, and physical conditions and is an almost universal early symptom of dementia. The concept of amnestic mild cognitive impairment attempts to describe those people in whom memory loss is not of such severity to merit a diagnosis of dementia. The importance of this group of people is not just the need to develop interventions which ameliorate individual suffering but that they represent a population at high risk of developing dementia, especially Alzheimer's disease, and are an appropriate target for dementia prevention strategies. STARTING POINT: K Kantarci and colleagues (Dement Geriatr Cogn Disord 2002; 14: 198-207) looked at the diagnostic accuracy of magnetic-resonance hippocampal volumetry and spectroscopy in patients with mild cognitive impairment, in normal older people, and in patients with Alzheimer's disease. Hippocampal volumes and N-acetyl aspartate/creatine spectroscopy were the most sensitive assessments discriminating people with mild cognitive impairment from Alzheimer's disease. Combination assessments were better at discriminating these two groups from normal controls. The histological underpinning of cognitive symptoms in older people has been demonstrated by the Cognitive Function and Ageing study (Lancet 2001; 357: 169-75), which showed that a third of people with no clinical evidence of dementia had histopathological hallmarks of Alzheimer's disease. WHERE NEXT? 25 million people across the world have dementia. Mild cognitive impairment, if a validated concept, represents an opportunity for preventing dementia. As more information becomes available about the cause of Alzheimer's disease and prospects emerge for prevention, identification of predementia states offers considerable scope to reduce the individual and societal cost of the illness. Continued validation of the criteria for mild cognitive impairment and studies of intervention should be a priority. As more evidence becomes available highlighting the relatively arbitrary nature of dementia diagnosis (based largely on interference with activities) and interventions become available for the prevention of dementia, mild cognitive impairment and related conditions will become more important.

Aged↗

PubMed2002

[Age- and education-specific reference values for the cognitive test of the SIDAM (Structured interview for the diagnosis of dementia of the Alzheimer type, multi-infarct dementia and dementias of other etiology according to ICD-10 and DSM-IV)].

The SIDAM (Structured Interview for the diagnosis of Dementia of the Alzheimer type, Multi-infarct dementia and dementias of other etiology according to ICD-10 and DSM-IV) is a standardized interview for the diagnosis of dementia. It can also be used as a screening instrument for the diagnosis of different syndromes of dementia and mild cognitive impairment. At present there is no age- or education-specific standardization. This report presents age- and education-specific norms for the cognitive assessment of the SIDAM, obtained in a population-based sample of elderly people aged 75 and over (n=1001).

Age Factors↗

PubMed2002

[Capacitive requirement for acute in-patient care of patients with psychosomatic diseases in bavaria].

Estimations of the requirement for acute in-patient care of patients with psychosomatic diseases in Bavaria have to rely on respective data on their incidence and prevalence as valid requirement data are missing. The required capacity of in-patient beds depends on several, inconsistently figured parameters: hospitalization rate, length of stay, occupancy rate. Based on conservative assumptions the hospitalization rate was calculated to be at least 1.3 admissions per 1000 and for adequate treatment the average length of stay should not be limited to less than 50 days. In order to avoid unnecessary delay of treatment a realistic occupancy rate has to be 90 %. Thus the minimal capacity for in-patient care is assessed to be 2453 beds. At present patients with psychosomatic diseases in Bavaria receive in-patient treatment in psychosomatic departments of general hospitals, hospitals and rehab clinics of psychosomatic and psychotherapeutic medicine, and in hospitals of psychiatry and psychotherapy, in each with a different focus. When the expertise was drafted these acute care and rehab hospitals provided some 2500 beds - with only 76 beds in general hospitals. For quality assessment of the available beds for in-patient care and future planning minimal standards of structural quality have to be consented. At present it is not possible to make a clear and substantial distinction between the treatment for patients with psychosomatic diseases in acute-care hospitals and in psychosomatic rehab clinics respectively. Thus, the necessary in-patient rehab capacity can only be assessed roughly. The existing pluralism of the in-patient care providing system for patients with psychosomatic diseases is considered to be appropriate for different needs of this patient group. In the future excellent care for this patient group will acknowledge options for a more flexible and interconnected care-providing system. This is a publication of the complete expertise by the project group "Acute In-patient Care for Patients with Psychosomatic Diseases in Bavaria" which has been handed to the Bavarian Ministry of Social Affairs in December 1999.

Delivery of Health Care↗

PubMedDate not supplied

P300 subcomponents in obsessive-compulsive disorder.

Hyperactivity in the frontal cortex, leading to acceleration of attentional and cognitive processes, is discussed as pathogenetic factor in obsessive-compulsive disorder (OCD), as supported by findings of neuroimaging studies. This dysfunction in patients with OCD could be reflected by the auditory event-related P300 component, since one subcomponent of the P300, the so-called P3a, is mainly generated in frontal regions. The P300 of 21 patients with OCD free of medication and 21 age- and sex-matched healthy controls was studied, and dipole source analysis was used, allowing the separation of the subcomponents P3a and P3b with high reliability. No difference concerning the P3a between OCD and healthy subjects was found. OCD patients, however, showed a larger P3b amplitude and a shorter P3b latency (only right hemisphere) as well as a shorter reaction time to target tones as the healthy controls. Since the P3b, generated mainly in the temporo-parietal junction, is related to attentional and higher cognitive functions, whereas the P3a is more related to unspecific orienting reactions, the P3b abnormalities found in these patients could be an electrophysiological correlate of overfocussed attention and faster cognitive processes in OCD, possibly due to higher arousal and noradrenergic function. Regarding the findings with small P300 amplitudes and long latencies in most of the other psychiatric patients, it is remarkable that OCD is one of the few psychiatric diseases being characterized by larger P3b amplitudes and shorter latencies.

Adult↗