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W Maier

Publications and source records attributed to W Maier.

At least 289 records · Page 16Linked to original sources
PubMed1995

Lack of gender differences in age at onset in familial schizophrenia.

One of the most consistent findings in the epidemiology of schizophrenia is that males are younger at the onset of schizophrenia than females. However, the vast majority of studies focussing on gender differences have not considered the potential influence of genetic factors on age at onset. We investigated the impact of familial loading on gender differences in age at onset in families with at least two siblings with RDC/DSM-III-R schizophrenia or chronic schizoaffective disorder. A total of 106 sib pairs, including 38 male-male pairs, 29 female-female pairs and 39 mixed-sex pairs of siblings as well as 260 male and 221 female isolated cases with no relative of first, second or third degree suffering from psychotic or major affective illness were investigated. We found no gender differences in age at onset in familial cases. An earlier age at onset in males compared to females was observed only in isolated cases. Our data strongly support the assumption that gender differences in age at onset of schizophrenia is not consistent across all subgroups of schizophrenics.

Adolescent↗
PubMed1995

The relationship between bipolar disorder and alcoholism: a controlled family study.

Bipolar disorder and alcoholism are familial disorders. The familial-genetic relationship between both is controversial and has received insufficient study. This study explores whether bipolar disorder and alcoholism share familial risk factors, and whether the co-occurrence of lifetime diagnosis of bipolar disorder and alcoholism is familial. We report on first-degree relatives of 146 consecutively admitted patients with either bipolar disorder or/and alcoholism; relatives of the patients (in total 728 relatives directly interviewed) were compared with first-degree relatives of 109 general population probands (320 relatives directly interviewed). Overlap between the familial components underlying bipolar disorder and alcoholism was not observed if the analysis was restricted to 'pure' diagnostic groups. Excess comorbidity between bipolar disorder and alcoholism was observed in relatives. Multiple sources for this excess of comorbidity between major affective disorders and alcoholism in families of probands with bipolar disorder are likely; in particular, we found evidence for a distinct subgroup of comorbid cases with familial comorbidity; however, excess comorbidity was also found in absence of familial loading with alcoholism.

Adolescent↗
PubMed1995

[Changes in the auditory threshold for air and bone conduction in relation to middle ear pressure in probands with normal hearing].

Under pressure in the tympanic cavity causes increased impedance of the middle ear. Gellé was the first to describe increased bone conduction levels following alteration of ear canal pressure in healthy ears. Up to now, no investigation which quantitatively describes the elevation of the hearing threshold induced by various levels of under pressure in the middle ear has been published. In a pressure chamber, we induced relative under pressure in the middle ears of 15 adults with normal hearing. We measured hearing thresholds and calculated medium values at four separate levels of under pressure. At an under pressure of 3.3 kPa, air conduction was reduced by a few dB at 500 and 1000 Hz. Alterations of bone conduction were first seen at 6.6 kPa accompanied by increased deterioration of air conduction. Both effects became more obvious at 10 kPa; and at a maximum under pressure of 13.3 kPa, a deterioration of air conduction by more than 25 dB was seen at 250, 500, and 1000 Hz. Bone conduction deteriorated by more than 10 dB at 500 and 1000 Hz. There was no uniformity in the development of bone conduction threshold in the condition of under pressure: Several ears expressed only slight changes, but in some ears we saw an increase of bone conduction at the same rate as air conduction. Minor alterations were observed in frequencies above 1000 Hz. These results may be only partially explained by middle ear effects like the reduction of the ostio-tympanic component of bone conduction caused by increased stiffness of the ossicles. We believe that disturbances of inner ear mechanics play a role in the deterioration of bone conduction levels, too.(ABSTRACT TRUNCATED AT 250 WORDS)

Acoustic Impedance Tests↗
PubMed1995

Identification of two novel polymorphisms and a rare deletion variant in the human dopamine D4 receptor gene.

We report two novel polymorphisms and a rare deletion variant in the human dopaine D4 receptor gene. The two polymorphisms are characterized by single base pair substitutions, namely a G-->C transversion changing codon 11 from GGG (encoding Gly) to CGG (encoding Arg) and a C-->T transition in position -11 upstream from the start codon. The Arg11 variant occurs at a frequency of about 1% and the C-->T transition at a frequency of about 7% in German control subjects (n = 148). Allele frequencies observed in patients suffering from schizophrenia (n = 256) and bipolar affective disorder (n = 99) were similar. The deletion variant is characterized by a 21 bp deletion affecting codons 36 to 42 coding for amino acids Ala-Ala-Leu-Val-Gly-Gly-Val located in the first transmembrane domain of the dopamine D4 receptor. The mutation was identified in a single individual suffering from obsessive-compulsive disorder and panic disorder. We were unable to detect the deletion in patients with schizophrenia and bipolar affective disorder, nor in healthy controls.

Adult↗
PubMed1995

Levels of a terpenoid glycoside (blumenin) and cell wall-bound phenolics in some cereal mycorrhizas.

Four cereals, Hordeum vulgare (barley), Triticum aestivum (wheat), Secale cereal (rye), and Avena sativa (oat), were grown in a defined nutritional medium with and without the arbuscular mycorrhizal fungus Glomus intraradices. Levels of soluble and cell wall-bound secondary metabolites in the roots of mycorrhizal and nonmycorrhizal plants were determined by high-performance liquid chromatography during the first 6 to 8 weeks of plant development. Whereas there was no difference in the levels of the cell wall-bound hydroxycinnamic acids, 4-coumaric and ferulic acids, there was a fungus-induced change of the soluble secondary root metabolites. The most obvious effect observed in all four cereals was the induced accumulation of a terpenoid glycoside. This compound was isolated and identified by spectroscopic methods (nuclear magnetic resonance, mass spectrometry) to be a cyclohexenone derivative, i.e. blumenol C 9-O-(2'-O-beta-glucuronosyl)-beta-glucoside. The level of this compound was found to be directly correlated with the degree of root colonization.

Avena↗
PubMed1995

Subclinical thought disorder in first-degree relatives of schizophrenic patients. Results from a matched-pairs study with the Thought Disorder Index.

To assess the frequency and quality of formal thought disorder in schizophrenic patients and their first-degree relatives, a consecutive series of 36 unmedicated patients, 20 siblings of these patients and 37 normal control subjects were examined with Holzman's Thought Disorder Index (TDI). As a proof of the internal validity of this tool, the patients demonstrated significantly more thought disorder than the controls as measured by the TDI total score and various subscores, which proved the internal validity of this tool in a German-speaking sample. In addition, in a pairwise comparison with controls who were individually matched by age and sex the patients' siblings had a significantly higher total TDI score and nonsignificant elevations on several subscores (combinatory and flippant). As to the level of severity of the thought disorder, the siblings mostly took an intermediate position between patients and controls. In conjunction with previous reports from other authors, our findings lend further support to the notion of subclinical thought disorder as an indicator of familial vulnerability to schizophrenia.

Adult↗
PubMed1995

Personality patterns in subjects at risk for affective disorders.

The main conclusions of this study on the familial links between personality patterns and affective disorders are: (1) The personality features with the greatest degree of symptomatic overlap with unipolar depression were more common among the first-degree relatives of probands with this diagnosis: thus dysthymic temperament and neuroticism are enhanced in this group of relatives compared to controls. Likewise personality features with a high degree of symptomatic overlap with bipolar affective disorder were more common among the first-degree relatives of probands with this diagnosis. Thus levels of dysthymic and cyclothymic temperament were elevated in this group of relatives compared to controls, whereas a familial link between neuroticism and bipolar disorder was not observed. (2) In addition, personality traits with only limited similarity with the syndromes of depression and mania were also found to be linked with affective disorders (obsessive-compulsive PD to bipolar disorders, rigidity to both subtypes of affective disorders). These associations have different implications regarding the association between personality/temperament conditions and disorders depending on the degree of overlap between symptoms and the personality trait. Those with substantial overlap may indicate the presence of a unitary disease process in which the enhancement of subthreshold affective traits may result in aggravation of behavior characteristics fulfilling the criteria of fullblown episodes of the disease. This relationship was particularly stressed by Kraepelin, Kretschmer, Clayton et al. and Akiskal. In this view personality and temperament patterns represent minor variants of the associate acute disorders. On the other hand, the relationship between dissimilar conditions may indicate the presence of a risk of underlying vulnerability factors which led to affective disorder only in the presence of additional risk factors. An example of the latter relationship in the present study is the aggregation of obsessive-compulsive and anancastic traits in families with affective disorders. Tellenbach focussed on this particular constellation. Epidemiological and family studies including these personality traits are too rare to fully appreciate the relevance of this particular relationship. Future prospective studies and family genetic studies which investigate the relationship between temperament, personality traits and disorders and affective syndromes are clearly indicated by the results presented herein.

Humans↗
PubMed1994

[Encephalopathy following poisoning with an anticholinergic agent].

A 55-year-old chemical laboratory technician developed mydriasis and ocular hypertension, which lasted for 6 weeks, after synthesizing several kilograms of a scopolamine-related test agent with anticholinergic action and then decanting a powdery intermediary substance, the dust of which he may have inhaled. Six weeks later he suddenly had symptoms of an acute intoxication while synthesizing a scopolamine-related substance. The anticholinergic delirium regressed completely within one day requiring no treatment. But subsequently he developed symptoms of a toxic encephalopathy. This only partially regressed over the following 3 years. Its probable cause is thought to have been either the manifestation of an already existing organic cerebral psychiatric syndrome or an as yet unknown effect of the test substance.

Acute Disease↗
PubMed1994

The relevance of recurrent brief depression in primary care. A report from the WHO project on Psychological Problems in General Health Care conducted in 14 countries.

This report from the WHO project on Psychological Problems in General Health Care examines the relevance in primary care of the concept of recurrent brief depression (RBD) proposed by Jules Angst. RBD refers to brief, severe depressive episodes that recur frequently, i.e. nearly once a month over a 1-year period, according to Angst. Using a structured interview (CIDI), RBD was assessed in patients not meeting the criteria for depressive episodes lasting at least 2 weeks, as defined in the ICD-10 (DE). A substantial proportion of primary care seekers were identified as presenting RBD without other depressive disorders, 3.7% with a formal RBD diagnosis and 2.7% with frequent but not monthly depressive episodes. These two subgroups were found to differ very little in terms of sociodemographic characteristics, severity, disability, and comorbidity with other diagnoses. However, in patients with a formal diagnosis of RBD, a higher rate of history of suicide attempts was found (14.0%), similar to that observed in patients meeting the criteria for DE. Most of the severity and disability indicators show that RBD is a severe condition, associated with substantial impairment, even if they show a higher degree of severity for DE. About one RBD patient out of three is recognized by general practitioners as presenting a psychological disorder, a majority of whom are actually treated. Our results confirm the relevance of the concept of RBD in primary care, and the need to further explore the pertinence of the restrictive recurrence criterion proposed by Angst.

Adolescent↗
PubMed1994

Brief depression among patients in general practice. Prevalence and variation by recurrence and severity.

Depression with substantial psychosocial impairment, but not qualifying as depressive disorder according to the standard diagnostic manuals, is frequent among primary care patients. Recurrent brief depression (RBD) is a diagnostic category intended to identify a major proportion of this group of patients. The WHO study on "Psychological Problems in Primary Health Care" was used as a vehicle to estimate the proportion of patients with this diagnosis and to evaluate the validity of this diagnosis as well as of alternative concepts of brief depression with multiple episodes. This study applies a two-stage sampling scheme; 300 patients also underwent an additional interview tailored for variants of brief depression. 7.6% of primary care patients were identified as RBD with the majority not receiving any other psychiatric diagnosis (DSM-III-R). These patients reported substantial psychosocial impairment, and the majority were identified as psychological cases by general practitioners. However, patients experiencing other variants of brief episodes were also found to be substantially psychosocially impaired, although they were not identified as psychiatric cases by DSM-III-R. Thus, a less restrictive definition of RBD is proposed. The diagnostic definition of RBD has a major impact on the sex ratio of cases: the less restrictive the diagnosis, the more balanced are the prevalence rates between males and females.

Adolescent↗
PubMed1994

Recurrent brief depression in general practice. Clinical features, comorbidity with other disorders, and need for treatment.

This study tested the clinical validity of the new diagnostic entity "recurrent brief depression" (RBD) in 300 general practice patients who participated in the WHO study on "Psychological Problems in Primary Care." Patients with current RBD reported of episodes major depression more often than did a comparison group of nondepressed general practice patients: however, the majority of RBD patients had not received a diagnostic of any well-established affective disorder during the last 12 months. RBD patients (without MDE) did not suffer more frequently from dysthymia, from nonaffective psychiatric disorders, or from somatic disorders. However, RBD was associated with a higher percentage of previous suicide attempts and of ideation of suicide and death. RBD was accompanied by substantial psychosocial impairment; psychosocial impairment in RBD patients could not be explained by excess comorbidity. Thus, the clinical validity of RBD was demonstrated although doubts about the appropriateness of the definition remained. This new diagnostic category needs more attention as only as small minority of patients with RBD received specific antidepressant treatment.

Activities of Daily Living↗
PubMed1994

Treatment of chronic depression with sulpiride: evidence of efficacy in placebo-controlled single case studies.

Systematic variation of treatment (alternating active drug and placebo in four treatment periods) in individual patients is proposed to collect preliminary evidence for a therapeutic effect of sulpiride in chronic depression; the ARIMA model is applied to evaluate the intervention effects of the tentatively effective treatment in single subjects. Ten single cases of chronic depression with a diagnosis of major depression or dysthymia were selected and seven of these provided evidence for beneficial effects of sulpiride with regard to treating the symptoms of depression and anxiety. However, the drug effects were intraindividually not always replicable. The results obtained with these single cases positively support the recommendation to perform regular randomized placebo-controlled trials with sulpiride in chronic depression. Simultaneously, these single case investigations reveal a lack of temporal stability of treatment response and inconsistencies of response with regard to different treatment targets in individual patients.

Adult↗
PubMed1994

Attentional abilities and measures of schizotypy: their variation and covariation in schizophrenic patients, their siblings, and normal control subjects.

Thirty-five schizophrenic patients in the early stages of illness, 26 of their healthy siblings, and 35 normal control subjects performed the Continuous Performance Test, Identical Pairs version (CPT-IP). Both schizophrenic patients and their siblings were significantly impaired in their attentional performance compared with normal subjects. These results support impaired attention as a vulnerability marker of schizophrenia and indicate that at-risk siblings of schizophrenic patients display attentional deficits comparable to those found for the offspring of schizophrenic parents. By contrast, a decline in performance with the onset of a distraction condition (auditory and visual stimuli) was seen only in schizophrenic patients; siblings and normal control subjects did not differ from one another in response to experimental distraction. Therefore, it was concluded that differential distractibility is likely to be a state marker of schizophrenia. In clinical assessments, healthy siblings rated themselves as experiencing significantly more physical anhedonia than did normal control subjects, but the siblings did not differ from normal control subjects in self-rated perceptual aberrations. Contrary to expectation, performance on the CPT-IP did not correlate significantly with either anhedonia or perceptual aberration in high-risk siblings. These results suggest that psychometrically measured "psychosis proneness" and neuropsychologically detected deficits may tap two nonoverlapping sources of vulnerability to schizophrenia.

Attention↗
PubMed1994

Absence of linkage between schizophrenia and the dopamine D4 receptor gene.

The dopamine D4 receptor gene and the closely placed tyrosine hydroxylase (TH) receptor gene are important candidate genes for schizophrenia; both are located on the short arm of chromosome 11. Multipoint linkage analyses excluded linkage of schizophrenia/schizoaffective disorder to both candidate genes in a sample of 15 multiplex and systematically recruited families. This result was not dependent on the definition of the affection status and on the specification of the mode of transmission (insofar as it is monogenic) of the disease. There was no evidence for a subgroup of families being linked. This result does not preclude the possibility that the D4 receptor gene or the TH gene has only a nonmajor effect on the genetic etiology of schizophrenia or that families in other populations are linked.

Genes, Dominant↗
PubMed1994

No evidence of linkage between the dopamine D2 receptor gene and schizophrenia.

The antipsychotic effects of dopamine D2 receptor antagonists (neuroleptics) and the psychotomimetic effects of dopamine agonists suggest that a defect of the D2 receptor gene might be a factor in the etiology of schizophrenia. Fifteen families that contained several members suffering from schizophrenia were tested for linkage between the D2 receptor gene and schizophrenia. In addition, four flanking markers were tested. The mode of inheritance was assumed to be dominant. Five different models of the affection status, which ranged from a narrow to a broad definition of the affection status, were studied. Linkage analysis was carried out with dominant, recessive, and intermediate modes of transmission. Two-point and multipoint analyses between schizophrenia and the D2 receptor gene resulted in log-likelihood differences < -2 for all five models, and linkage between this candidate gene and schizophrenia was excluded. A mutation in the D2 receptor gene itself is therefore extremely unlikely to be related to a higher susceptibility to schizophrenia, at least in the present group of families.

Bipolar Disorder↗