Michael Riedel

Ludwig-Maximilians-University of Munich, München, Bavaria, Germany

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Publications (254)812.98 Total impact

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    ABSTRACT: The aim of this study was to evaluate residual symptoms in patients achieving remission according to the consensus criteria and to analyze their potential influence on the patient's outcome one year after discharge. In total, 399 patients suffering from a schizophrenia spectrum disorder were evaluated within a naturalistic study. Remission status was examined using the consensus criteria. Residual symptoms were defined as any symptom present at the time-point of remission following analogous analyses performed in depressed patients. Therefore, a PANSS item with a symptom severity of >1 (= at least borderline mentally ill) was defined to be a residual symptom. Remitters with and without residual symptoms were compared regarding psychopathology, functioning and side effects. In total, 236 patients (59 %) were remitters at discharge with 94 % of them suffering from at least one residual symptom. The most common residual symptoms were blunted affect (49 %), conceptual disorganization (42 %) and social withdrawal (40 %). A significant association was found between the presence of residual symptoms and the severity of side effects (p < 0.0001) and functioning (p = 0.0003) at discharge as well as between residual symptoms and the risk of relapse and chance of remission one year after discharge. Residual symptoms were highly prevalent in remitted schizophrenia inpatients following the suggested definition. Most residual symptoms were persistent baseline symptoms suggesting an ongoing illness severity. Also, the necessity to re-evaluate the consensus criteria questioning the status of remission in these patients is also pointed out.
    European Archives of Psychiatry and Clinical Neuroscience 09/2014; · 3.36 Impact Factor
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    ABSTRACT: We pharmacologically challenged catecholamine reuptake, using methylphenidate, in order to investigate its effects on brain activity during a motor response inhibition task as a function of the 3'-UTR variable number of tandem repeats (VNTR) polymorphism of the dopamine transporter (DAT) gene (SLC6A3) and the availability of DATs in striatum. We measured the cerebral hemodynamic response of 50 healthy males during a Go/No-Go task, a measure of cognitive control, under the influence of 40 mg methylphenidate and placebo using 3T functional magnetic resonance imaging (fMRI). Subjects were grouped into 9-repeat (9R) carriers and 10/10 homozygotes on the basis of the SLC6A3 VNTR. During successful no-go trials compared to oddball trials, methylphenidate induced an increase of blood-oxygen-level-dependent (BOLD) signal for carriers of the SLC6A3 9R-allele but a decrease in 10/10 homozygotes in a thalamo-cortical network. The same pattern was observed in caudate and inferior frontal gyrus when successful no-go trials were compared to successful go trials. We additionally investigated in a subset of 35 participants whether baseline striatal DAT availability, ascertained with (123)I-FP-CIT single photon emission computed tomography (SPECT), predicted the amount of methylphenidate-induced change in hemodynamic response or behavior. Striatal DAT availability was nominally greater in 9R carriers compared to 10/10 homozygotes (d=0.40), in line with meta-analyses, but did not predict BOLD or behavioral changes following MPH administration. We conclude that the effects of acute MPH administration on brain activation are dependent on DAT genotype, with 9R carriers showing enhanced BOLD following administration of a pro-dopaminergic compound.Neuropsychopharmacology accepted article preview online, 15 September 2014. doi:10.1038/npp.2014.240.
    Neuropsychopharmacology: official publication of the American College of Neuropsychopharmacology 09/2014; · 8.68 Impact Factor
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    ABSTRACT: Methylphenidate (MPH) is an indirect dopaminergic and noradrenergic agonist that is used to treat attention deficit hyperactivity disorder and that has shown therapeutic potential in neuropsychiatric diseases such as depression, dementia, and Parkinson's disease. While effects of MPH on task-induced brain activation have been investigated, little is known about how MPH influences the resting brain. To investigate the effects of 40 mg of oral MPH on intrinsic functional connectivity, we used resting state fMRI in 54 healthy male subjects in a double-blind, randomized, placebo-controlled study. Functional connectivity analysis employing ICA revealed seven resting state networks (RSN) of interest. Connectivity strength between the dorsal attention network and the thalamus was increased after MPH intake. Other RSN located in association cortex areas, such as the left and right frontoparietal networks and the executive control network, showed MPH-induced connectivity increase to sensory-motor and visual cortex regions and connectivity decrease to cortical and subcortical components of cortico-striato-thalamo-cortical circuits (CST). RSN located in sensory-motor cortex areas showed the opposite pattern with MPH-induced connectivity increase to CST components and connectivity decrease to sensory-motor and visual cortex regions. Our results provide evidence that MPH does not only alter intrinsic connectivity between brain areas involved in sustained attention, but that it also induces significant changes in the cortico-cortical and cortico-subcortical connectivity of many other cognitive and sensory-motor RSN. Hum Brain Mapp, 2014. © 2014 Wiley Periodicals, Inc.
    Human Brain Mapping 05/2014; · 6.88 Impact Factor
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    ABSTRACT: In randomized controlled trials, maintenance treatment for relapse prevention has been proven to be efficacious in patients responding in acute treatment, its efficacy in long-term outcome in "real-world patients" has yet to be proven. Three-year long-term data from a large naturalistic multisite follow-up were presented. Severe relapse was defined as suicide, severe suicide attempt, or rehospitalization. Next to relapse rates, possible risk factors including antidepressant medication were identified using univariate generalized log-rank tests and multivariate Cox proportional hazards model for time to severe relapse. Overall data of 458 patients were available for analysis. Of all patients, 155 (33.6 %) experienced at least one severe relapse during the 3-year follow-up. The following variables were associated with a shorter time to a severe relapse in univariate and multivariate analyses: multiple hospitalizations, presence of avoidant personality disorder, continuing antipsychotic medication, and no further antidepressant treatment. In comparison with other studies, the observed rate of severe relapse during 3-year period is rather low. This is one of the first reports demonstrating a beneficial effect of long-term antidepressant medication on severe relapse rates in naturalistic patients. Concomitant antipsychotic medication may be a proxy marker for treatment resistant and psychotic depression.
    European Archives of Psychiatry and Clinical Neuroscience 03/2014; · 3.36 Impact Factor
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    ABSTRACT: Obsessive-compulsive symptoms (OCS) constitute a major comorbidity in schizophrenia. Prevalence estimations of OCS for patients with at-risk mental states (ARMS) for psychosis vary largely. It is unclear how ARMS patients with or without comorbid OCS differ regarding general psychosocial functioning, psychotic and affective symptoms and neurocognitive abilities. At-risk mental states patients (n = 233) from the interventional trial PREVENT (Secondary Prevention of Schizophrenia) were stratified according to the presence or absence of comorbid OCS and compared on several clinical variables. Patients, who fulfilled the criteria for obsessive-compulsive disorder (OCD) or presented with subclinical OCS (ARMSposOCS sample), did not significantly differ from patients without OCS (ARMSnegOCS) with regard to gender, age, premorbid verbal intelligence and levels of education. Furthermore, similar severity of depressive syndromes, basic cognitive, attenuated psychotic and brief limited intermittent psychotic symptoms were found. However, ARMSposOCS patients showed more impairment of psychosocial functioning and higher general psychopathology. In contrast, they scored higher in cognitive tasks measuring working memory and immediate verbal memory. Findings extend upon previous results due to the multidimensional assessment. Subsequent longitudinal studies might elucidate how comorbid OCS influence differential treatment response, especially to cognitive behavioural interventions and the transition rates to psychosis.
    Acta Psychiatrica Scandinavica 02/2014; · 4.86 Impact Factor
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    ABSTRACT: Pleckstrin homology domain (PH domain) comprises approximately 120 amino acids and is integrated in a wide range of proteins involved in intracellular signaling or as constituents of the cytoskeleton. This domain can bind phosphatidylinositol (3,4,5)-triphosphate and phosphatidylinositol (4,5)-biphosphate and proteins such as the βγ-subunits of heterotrimeric G proteins and protein kinase C. Associations with psychiatric diseases have not been investigated yet. To identify genes involved in response to antipsychotics, mice were treated with haloperidol (1 mg/kg, n = 11) or saline (n = 12) for one week. By analyzing microarray data, we observed an increase of pleckstrin homology domain containing 6 (PLEKHA6) gene expression. Furthermore, we genotyped 263 schizophrenic patients, who were treated monotherapeutically with different antipsychotics within randomized-controlled trials. Psychopathology was measured weekly using the PANSS for a minimum of four and a maximum of twelve weeks. Correlations between PANSS subscale scores at baseline and PANSS improvement scores after four weeks of treatment and genotypes were calculated by using a linear model for all investigated SNPs. We found associations between four PLEKHA6 polymorphisms (rs17333933 (T/G), rs3126209 (C/T), rs4951338 (A/G) and rs100900571 (T/C)) and different PANSS subscales at baseline. Furthermore two different polymorphisms (rs7513240 (T/C), rs4951353 (A/G)) were found to be associated with therapy response in terms of a significant correlation with different PANSS improvement subscores after four weeks of antipsychotic treatment. Our observation of an association between genetic polymorphisms of a protein of the PH domain and psychopathology data in schizophrenic patients might be indicative for an involvement of PLEKHA6 in the pathophysiology of schizophrenia and the therapy response towards antipsychotics.
    Progress in Neuro-Psychopharmacology and Biological Psychiatry 01/2014; 51:190–195. · 3.55 Impact Factor
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    ABSTRACT: An imbalance of tryptophan metabolites plays a role in the pathophysiology of schizophrenia. Also cytokines seem to be involved and are able to enhance the tryptophan metabolism. In this study the impact of cytokines, tryptophan metabolites and antipsychotics was evaluated in schizophrenic patients/ healthy controls and correlated with the psychopathology of schizophrenia. This study investigated 12 patients with schizophrenia and 24 matched controls. Peripheral blood mononuclear cell cultures were stimulated in vitro with lipopolysaccharide (LPS) or polyinosine-polycytidylic acid (poly I:C) and different antipsychotics (quetiapine, risperidone, haloperidole and clozapine) were added. The cytokines IL-4, IL-10, IFN-γ and tryptophan metabolites were analysed. Symptom severity was assessed using the positive and negative syndrome scale (PANSS). Peripheral mononuclear cells of schizophrenia patients showed a reduced IFN-γ response to LPS (p=0.008). When quetiapine and risperidone were added this imbalance between patients and controls disappeared. Tryptophan levels were significantly lower in patients' cells cultures when the cells were stimulated with LPS (p=0.029). A group effect for lower levels in the patients' cell culture was evaluated for tryptophan and kynurenine (p=0.043; p=0.05). In addition, high tryptophan levels correlated with low PANSS negative scores in patients and higher kynurenine levels resulted in higher PANSS positive scores. Only two atypical antipsychotics were identified to reverse the imbalanced cytokine levels in schizophrenia. The low concentrations of tryptophan and kynurenine in these patients could be a sign of a fast degradation of tryptophan - yet tryptophan metabolites could not be changed by any of the investigated antipsychotics.
    Psychiatria Danubina 12/2013; 25(4):389-97. · 0.63 Impact Factor
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    ABSTRACT: Objective: The study aimed to examine suicidal behaviour during in-patient care in a psychiatric university hospital.Method: Based upon a psychiatric basic documentation system prevalence and risk factors of in-patient suicides and suicide attempts were investigated (1995 - 2010).Results: A total of 42 in-patient suicides and 166 attempts were found among 16 251 patients. According to the multivariate logistic regression analysis the risk of suicide during hospitalization increases significantly for male patients, with more previous psychiatric hospitalizations and suicidality according to clinical impression at admission or suicide attempt before admission. Patients with affective or schizophrenic disorders were at highest risk. The following risk factors are associated with suicide attempt during stay: female gender, borderline personality disorder (F60.3), more previous psychiatric hospitalizations, shorter duration of disorder, earlier age of onset, suicidality according to clinical impression at admission or suicide attempt before admission.Conclusion: As depressive and schizophrenic patients represent the high-risk group of in-patient suicide, suicide prevention should be a major goal in their treatment. More frequent suicide risk assessment is recommended particularly before granting a leave or an outing.
    Psychiatrische Praxis 07/2013; · 1.64 Impact Factor
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    ABSTRACT: With the widespread use of atypical or second-generation antipsychotics, switching treatment has become current practice and more complicated, as the pharmacological profiles of these agents differ substantially despite their similarity in being 'atypical'. All share the ability to block dopamine D2 receptors, and most of them also block serotonin 5-HT2A receptors. Apart from these common features, some atypical antipsychotics are also able to block or stimulate other dopamine or serotonin receptors, as well as histaminergic, muscarinergic or adrenergic receptors. As a result of the varying receptor affinities, in switching or discontinuing compounds several possible pitfalls have to be considered, including the occurrence of withdrawal and rebound syndromes. This article reviews the pharmacological background of functional blockade or stimulation of receptors of interest in regard to atypical antipsychotics and the implicated potential withdrawal and rebound phenomena. A MEDLINE search was carried out to identify information on withdrawal or rebound syndromes occurring after discontinuation of atypical antipsychotics. Using the resulting literature, we first discuss the theoretical background to the functional consequences of atypical antipsychotic-induced blockade or stimulation of neurotransmitter receptors and, secondly, we highlight the clinical consequences of this. We then review the available clinical literature on switching between atypical antipsychotics, with respect to the occurrence of withdrawal or rebound symptoms. Finally, we offer practical recommendations based on the reviewed findings. The systematic evaluation of withdrawal or rebound phenomena using randomized controlled trials is still understudied. Knowledge of pharmacological receptor-binding profiles may help clinicians in choosing adequate switching or discontinuation strategies for each agent. Results from large switching trials indicate that switching atypical antipsychotics can be performed in a safe manner. Treatment-emergent adverse events during or after switching are not always considered to be, at least in part, associated with the pre-switch antipsychotic. Further studies are needed to substantiate the evidence gained so far on different switching strategies. The use of concomitant medication, e.g., benzodiazepines or anticholinergic drugs, may help to minimize symptoms arising from the discontinuation or switching of antipsychotic treatment.
    CNS Drugs 07/2013; · 4.38 Impact Factor
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    ABSTRACT: This cross-cultural study was designed to examine cultural differences in empathy levels of first-year medical students. A total of 257 students from the academic year 2010/11, 131 at Jimma University, Ethiopia, and 126 at the Ludwig Maximilian University, Munich, Germany, completed the Balanced Emotional Empathy Scale (BEES), the Reading the Mind in the Eyes (RME-R) test, and a questionnaire on sociodemographic and cultural characteristics. Furthermore, we conducted a qualitative analysis of the students' personal views on the definition of empathy and possible influencing factors. Group comparisons and correlation analyses of empathy scores were performed for the entire cohort and for the Jimma and Munich students separately. We used a regression tree analysis to identify factors influencing the BEES. The male students in Jimma (39.1 ± 22.3) scored significantly higher in the BEES than those male students from Munich (27.2 ± 22.6; p = 0.0002). There was no significant difference between the female groups. We found a moderate, positive correlation between the BEES and RME-R test, i.e. between emotional and cognitive empathy, within each university. Nevertheless, the RME-R test, which shows only Caucasian eyes, appears not to be suitable for use in other cultures. The main findings of our study were the influence of culture, religion, specialization choice, and gender on emotional empathy (assessed with the BEES) and cognitive empathy (assessed with the RME-R test) in first-year medical students. Further research is required into the nature of empathy in worldwide medical curricula.
    Ethiopian journal of health sciences. 07/2013; 23(2):113-22.
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    ABSTRACT: Schizophrenia patients have deficits in cognitive control as well as in a number of emotional domains. The antisaccade task is a measure of cognitive control that requires the inhibition of a reflex-like eye movement to a peripheral stimulus. Antisaccade performance has been shown to be modulated by the emotional content of the peripheral stimuli, with emotional stimuli leading to higher error rates than neutral stimuli, reflecting an implicit emotion processing effect. The aim of the present study was to investigate the impact on antisaccade performance of threat-related emotional facial stimuli in schizophrenia patients, first-degree relatives of schizophrenia patients and healthy controls. Fifteen patients, 22 relatives and 26 controls, matched for gender, age and verbal intelligence, carried out an antisaccade task with pictures of faces displaying disgusted, fearful and neutral expressions as peripheral stimuli. We observed higher antisaccade error rates in schizophrenia patients compared to first-degree relatives and controls. Relatives and controls did not differ significantly from each other. Antisaccade error rate was influenced by the emotional nature of the stimuli: participants had higher antisaccade error rates in response to fearful faces compared to neutral and disgusted faces. As this emotional influence on cognitive control did not differ between groups we conclude that implicit processing of emotional faces is intact in patients with schizophrenia and those at risk for the illness.
    Brain and Cognition 06/2013; 82(3):329-336. · 2.82 Impact Factor
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    ABSTRACT: AIM: An imbalance between T-helper type 1 (Th1) and type 2 (Th2) cytokines has been implicated in schizophrenia, although empirical evidence is rare. The aim of this study was to examine if a Th1/Th2 imbalance occurs in schizophrenia and schizophrenia-related disorder. METHODS: Twenty-six subjects with schizophrenia, 26 subjects with schizophrenia-related disorders, and 26 healthy controls were recruited. The Human Th1/Th2 Cytokine Cytometric Bead Array Kit-II was utilized to assess serum Th1/Th2 cytokines and ratios simultaneously. MANOVA was used to detect differences among the three diagnostic groups in distinct Th1/Th2 cytokines/ratios. Pearson/Spearman correlations were used to examine the relationships between distinct Th1/Th2 cytokines/ratios and clinical/psychopathological data in schizophrenia. RESULTS: Interferon (IFN)-γ/interleukin (IL)-4, IFN-γ/IL-10, IL-2/IL-4, and tumor necrosis factor (TNF)-α/IL-4 ratios were significantly decreased in schizophrenia, but not in schizophrenia-related disorders compared to healthy controls. IFN-γ/IL-4 and IFN-γ/IL-10 in schizophrenia subjects positively correlated with age, but not in schizophrenia-related disorder subjects or in healthy controls. CONCLUSION: A clear Th2 shift was observed in schizophrenia, but not in schizophrenia-related disorders. The Th2 shift in schizophrenia appeared to be an aberrant developmental phenomenon.
    Psychiatry and Clinical Neurosciences 05/2013; 67(4):228-236. · 2.04 Impact Factor
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    ABSTRACT: OBJECTIVE: Full and sustained symptom remission is a major treatment objective after a first-episode in schizophrenia. Findings regarding differences in remission between first- and second-generation antipsychotics are inconclusive. This study aimed to provide rates and predictors of remission in first-episode schizophrenia and to identify symptoms that prevent remission. METHODS: Prevalence rates of "symptomatic remission" (symptom criteria only) and "enduring remission" (symptom and 6-month time criteria), defined according to Andreasen et al. (2005), were determined in first-episode patients participating in a RCT by the German Research Network on Schizophrenia (GRNS) that compared post-acute, 1-year maintenance treatment with risperidone or haloperidol. Respective predictors at baseline were identified by logistic and Cox regression analysis. RESULTS: Prevalence rates were 91.5% for symptomatic remission (n=152/166 eligible patients) and 58.6% for enduring remission (n=65 of 111 patients who continued for at least 6months; 39.2% of all 166 patients included), with no significant differences between risperidone and haloperidol in either type of remission. Enduring remission often was not reached because of negative symptoms: After 6months, 40.5% of the patients had at least 1 negative symptom, whereas only 10.8% of the patients had "persisting" positive symptoms. Of the different predictors identified in univariate analyses, (lower) negative symptoms and participating in standardized psychological treatment remained significant in multivariate (stepwise forward) analyses for enduring remission. CONCLUSIONS: By far most of the first-episode patients reached a temporary state of full symptomatic remission within 1year of antipsychotic treatment. However, only about 50% achieved sustained, enduring remission. Negative symptoms are still a major treatment obstacle to enduring remission in schizophrenia.
    Schizophrenia Research 05/2013; · 4.59 Impact Factor
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    ABSTRACT: Several theoretical accounts assume that interference control deficits belong to the core symptoms of adult ADHD. However, findings of increased interference effects in adult ADHD patients compared with healthy adults may be confounded with the simultaneous finding of generally slower responses in the patient group. The current study compared the magnitude of the interference effect in the Stroop task between a group of adults with ADHD and a healthy adult control group in a procedure that accounted for differences in overall response speed by using delta plots. The amount of interference did not differ between patient and control group at comparable reaction time levels. These results challenge the conclusions of the previous studies, in that they indicate that interference control is not impaired in adult ADHD.
    Acta psychologica 03/2013; 143(1):71-78. · 2.19 Impact Factor
  • The Journal of Clinical Pharmacology 02/2013; · 2.84 Impact Factor
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    ABSTRACT: Impulsivity characterises various psychiatric disorders, particularly attention-deficit/hyperactivity disorder (ADHD). Evidence shows that ADHD symptoms are associated with dopamine dysfunction and alleviated with methylphenidate, a drug that reduces dopamine transporter availability. ADHD-like symptoms and impulsive traits are continuously distributed across the general population. Here, we aimed to investigate the dopaminergic basis of impulsivity and other ADHD-related traits in healthy individuals by studying the association of these traits with striatal dopamine transporter availability. Single-photon emission computed tomography with [(123)I] FP-CIT was performed on 38 healthy males. Impulsivity was measured using the Barratt Impulsiveness Scale (BIS) and hyperactivity-impulsivity and inattention using the Adult ADHD Self-Report Scale (ASRS). We found that greater dopamine transporter availability was associated with higher BIS impulsivity but not with ADHD-related traits. The association with BIS was significant after accounting for individual differences in age and neuroticism. These results suggest that individual differences in the dopamine system may be a neural correlate of trait impulsivity in healthy individuals.
    Psychiatry research. 11/2012;
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    ABSTRACT: Recent research using individual task settings suggests that a major problem in schizophrenia is a dysfunctional theory of mind system leading to false mental state attributions. However, if a more low-level deficit to integrate own and other’s actions (action blindness) is present in schizophrenia is still unknown. Using a Social Simon task, we tested if schizophrenia patients have a deficit in self-other integration. Further, we tested for a possible genetic bias of this dysfunction by studying clinically unaffected first-degree relatives of schizophrenia patients. While schizophrenia patients showed no Social Simon effect, we found a reliable Social Simon effect in healthy participants and first-degree relatives of schizophrenia patients. Joint task performance differed statistically between patients and healthy controls. We did not find any differences in the size of the Social Simon effects of relatives and healthy controls. The present findings suggest that schizophrenia patients have severe problems with self-other integration, which may lead to problems in social interactions. Since first-degree relatives of schizophrenia patients showed a reliable Social Simon effect, the evidence for a genetic bias of this social dysfunction in schizophrenia however is weak.
    Neuropsychologia 11/2012; · 3.48 Impact Factor
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    ABSTRACT: Factors contributing to treatment-emergent suicidal ideation (TESI) using antidepressants have been in the focus of recent research strategies. We investigated previously established clinical predictors of TESI and combined these with several polymorphisms of candidate genes in patients with major depressive disorder. Common polymorphisms involved in the tryptophan hydroxylase 1 (TPH1) and 2 (TPH2), serotonin transporter, monoamine oxidase A (MAOA) and brain-derived neurotrophic factor (BDNF) were investigated in a naturalistic inpatient study of the German research network on depression. We compared patients showing TESI with non-TESI suicidal patients and with non-suicidal patients using univariate tests to detect relevant factors, which were further tested in logistic regression and CART (Classification and Regression Trees) analyses. Of the 269 patients, TESI occurred in 22 patients (17 female), 117 patients were defined as non-TESI suicidal patients, and 130 patients were classified as non-suicidal. When comparing cases with both control groups we found the TPH2 rs1386494 (C/T) polymorphism to be moderately associated with TESI (Univariate tests: TESI vs. non-suicidality: p=0.005; adjusted: p=0.09; TESI vs. non-TESI suicidal patients: p=0.0024; adjusted: p=0.086). This polymorphism remained the only significant genetic factor in addition to clinical predictors in logistic regression and CART analyses. CART analyses suggested interactions with several clinical predictors. Haplotype analyses further supported a contribution of this polymorphism in TESI. The TPH2 rs1386494 (C/T) polymorphism might contribute to the genetic background of TESI. This polymorphism has been previously associated with committed suicide and major depressive disorder. The small number of cases warrants replication in larger patient samples. Lack of a placebo control group hampers definite conclusions on an association with antidepressive treatment.
    European neuropsychopharmacology: the journal of the European College of Neuropsychopharmacology 10/2012; · 3.68 Impact Factor
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    ABSTRACT: The role of the brain-derived neurotrophic factor (BDNF) in the pathophysiology of major depressive disorder (MDD) remains to be elucidated. Recent post hoc analyses indicated a potential association of three polymorphisms in the BDNF gene with worse treatment outcome in patients with the subtype of melancholic depression. We aimed at replicating these findings in a German naturalistic multicenter follow-up. Three polymorphisms in the BDNF gene (rs7103411, rs6265 (Val66Met) and rs7124442) were genotyped in 324 patients with MDD and 470 healthy controls. We applied univariate tests and logistic regression models stratifying for depression subtype and gender. The three polymorphisms were not associated with MDD as diagnosis. Further, no associations were found in univariate tests. With logistic regression, we only found a tendency towards an association of the rs6265 (Val66Met) polymorphism with overall response to treatment (response rates: GG (val/val) < GA (val/met) < AA (met/met); p = 0.0129) and some gender differences for the rs6265 (Val66Met) and rs7103411 polymorphisms. Treatment outcome stratified for subtypes of depression did not differ significantly between the investigated polymorphisms or using haplotype analyses. However, results showed a tendency towards significance. At this stage, we cannot support an influence of these three polymorphisms. Further studies in larger patient samples to increase sample sizes of subgroups are warranted.
    European Archives of Psychiatry and Clinical Neuroscience 09/2012; · 3.36 Impact Factor
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    ABSTRACT: Schennach R, Riesbeck M, Mayr A, Seemüller F, Maier W, Klingberg S, Heuser I, Klosterkötter J, Gastpar M, Schmitt A, Sauer H, Schneider F, Jäger M, Wölwer W, Gaebel W, Möller H-J, Riedel M. Should early improvement be re-defined to better predict the maintenance of response in first-episode schizophrenia patients? Objective:  To evaluate the predictive validity of early response in first-episode schizophrenia within a 1-year follow-up trial and to compare the resulting cutoff to the currently proposed early response definition (20% improvement by week 2). Method:  Receiver operator characteristic (ROC) analyses were used to identify the predictive validity of the psychopathological improvement of treatment from week 1 to week 8, regarding the maintenance of response until week 52 as well as to define the most reasonable cutoff in 132 first-episode patients. The Youden Index (maximum of sensitivity and specificity) was used to compare the newly developed and the commonly used early response definition. Results:  Starting with week 6, a reasonable validity to predict the maintenance of response was found (area under the curve = 0.721) with the best fitting cutoff being a 51.6% PANSS total score improvement. Using this cutoff 74 patients (56%) were correctly identified to become responder and maintain response during follow-up (sensitivity: 0.747). The Youden Index was higher applying the newly developed early response cutoff featuring higher specificity compared to the commonly used early response definition. Conclusion:  Regarding long-term treatment, it seems more appropriate to base predictions of the patient's maintenance of response not before 6 weeks of treatment.
    Acta Psychiatrica Scandinavica 09/2012; · 4.86 Impact Factor

Publication Stats

3k Citations
812.98 Total Impact Points

Institutions

  • 1997–2014
    • Ludwig-Maximilians-University of Munich
      • • Department of Psychiatry
      • • Department of Neurology
      • • Hospital and Clinic of Psychiatry and Psychotherapy Poli
      München, Bavaria, Germany
  • 2013
    • Bezirksklinikum Regensburg
      Ratisbon, Bavaria, Germany
  • 2011–2013
    • Heinrich-Heine-Universität Düsseldorf
      Düsseldorf, North Rhine-Westphalia, Germany
    • University of Zurich
      Zürich, Zurich, Switzerland
  • 2012
    • University of Münster
      Muenster, North Rhine-Westphalia, Germany
  • 2006–2010
    • University of Technology Munich
      • Klinik und Poliklinik für Psychiatrie und Psychotherapie
      München, Bavaria, Germany
  • 2009
    • University Hospital München
      München, Bavaria, Germany
  • 2003
    • UCL Eastman Dental Institute
      Londinium, England, United Kingdom
  • 2001
    • Freie Universität Berlin
      • Department of Psychiatry
      Berlin, Land Berlin, Germany
  • 1998
    • Max von Pettenkofer-Institut
      München, Bavaria, Germany