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BACKGROUND: The UN Convention on the Rights of Persons with Disabilities, and the reformed guardianship law in Germany, require that persons with a disability, including people with dementia in Alzheimer's disease (PwAD), are supported in making self-determined decisions. This support is achieved through communication. While content-related communication is a deficit of PwAD, relational aspects of communication are a resource. Research in supported decision-making (SDM) has investigated the effectiveness of different content-related support strategies for PwAD but has only succeeded in improving understanding, which, although one criterion of capacity to consent, is not sufficient to ensure overall capacity to consent. The aim of the 'spatial intervention study' of the DECIDE project is to examine an innovative resource-oriented SDM approach that focuses on relational aspects. We hypothesise that talking to PwAD in their familiar home setting (as opposed to a clinical setting) will reduce the complexity of the decision-making process and enhance overall capacity to consent. METHODS: People with a suspected or confirmed diagnosis of dementia in Alzheimer's disease will be recruited from two memory clinics (N = 80). We will use a randomised crossover design to investigate the intervention effect of the decision-making place on capacity to consent. Besides reasoning capacity, which is part of overall capacity to consent and will be the primary outcome, various secondary outcomes (e.g., other aspects of capacity to consent, subjective task complexity, decisional conflict) and suspected moderating or mediating variables (e.g., meaning of home, demographic characteristics) will be assessed. DISCUSSION: The results of the study will be used to develop a new SDM strategy that is based on relational resources for PwAD. If a change in location achieves the anticipated improvement in capacity to consent, future research should focus on implementing this SDM strategy in a cost-effective manner in clinical practice. TRIAL REGISTRATION: DRKS00030799 .
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Enfermedad de Alzheimer , Humanos , Alemania , Toma de DecisionesRESUMEN
BACKGROUND: Everybody has the right to decide whether to receive specific medical treatment or not and to provide their free, prior and informed consent to do so. As dementia progresses, people with Alzheimer's dementia (PwAD) can lose their capacity to provide informed consent to complex medical treatment. When the capacity to consent is lost, the autonomy of the affected person can only be guaranteed when an interpretable and valid advance directive exists. Advance directives are not yet common in Germany, and their validity is often questionable. Once the dementia diagnosis has been made, it is assumed to be too late to write an advance directive. One approach used to support the completion of advance directives is 'Respecting Choices'®-an internationally recognised, evidence-based model of Advance Care Planning (ACP), which, until now, has not been evaluated for the target group of PwAD. This study's aims include (a) to investigate the proportion of valid advance directives in a memory clinic population of persons with suspected AD, (b) to determine the predictors of valid advance directives, and (c) to examine whether the offer of ACP can increase the proportion of valid advance directives in PwAD. METHOD: We intend to recruit at least N = 250 participants from two memory clinics in 50 consecutive weeks. Of these, the first 25 weeks constitute the baseline phase (no offer of ACP), the following 25 weeks constitute the intervention phase (offer of ACP). The existence and validity of an advance directive will be assessed twice (before and after the memory clinic appointment). Moreover, potential predictors of valid advance directives are assessed. DISCUSSION: The results of this study will enhance the development of consent procedures for advance directives of PwAD based on the ACP/Respecting Choices (R) approach. Therefore, this project contributes towards increasing the autonomy and inclusion of PwAD and the widespread acceptance of valid advance directives in PwAD. Trial Registration DRKS, DRKS00026691, registered 15th of October 2021, https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00026691.
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Planificación Anticipada de Atención , Enfermedad de Alzheimer , Humanos , Estudios Prospectivos , Directivas Anticipadas , RespetoRESUMEN
Importance: Insufficient treatment response and resulting chronicity constitute a major problem in depressive disorders. Remission rates range as low as 15% to 40% and treatment-resistant depression (TRD) is associated with low-grade inflammation, suggesting anti-inflammatory interventions as a rational treatment strategy. Minocycline, which inhibits microglial activation, represents a promising repurposing candidate in the treatment of TRD. Objective: To determine whether 6 weeks of minocycline as add-on to antidepressant treatment as usual can significantly reduce depressive symptoms in patients with TRD. Design, Setting, and Participants: The study was conducted in Germany and designed as a multicenter double-blind randomized clinical trial (RCT) of 200 mg/d minocycline treatment over a course of 6 weeks with a 6-month follow-up. Participants were recruited from January 2016 to August 2020 at 9 university hospitals that served as study sites. Key inclusion criteria were a diagnosis of major depressive disorder (according to Diagnostic and Statistical Manual of Mental Disorders [Fifth Edition] criteria), severity of depressive symptoms on the Hamilton Depression Rating Scale (HAMD-17) greater than or equal to 16 points, aged 18 to 75 years, body mass index 18 to 40, Clinical Global Impression Scale (CGI-S) greater than or equal to 4, failure to adequately respond to an initial antidepressant standard medication as per Massachusetts General Hospital Antidepressant Treatment History Questionnaire, and stable medication for at least 2 weeks. A total of 258 patients were screened, of whom 173 were randomized and 168 were included into the intention-to-treat population. Statistical analysis was performed from April to November 2020. Interventions: Participants were randomized (1:1) to receive adjunct minocycline (200 mg/d) or placebo for 6 weeks. Main Outcomes and Measures: Primary outcome measure was the change in Montgomery-Åsberg Depression Rating Scale (MADRS) score from baseline to week 6 analyzed by intention-to-treat mixed model repeated measures. Secondary outcome measures were response, remission, and various other clinical rating scales. Results: Of 173 eligible and randomized participants (84 randomized to minocycline and 89 randomized to placebo), 168 formed the intention-to-treat sample (79 [47.0%] were women, 89 [53.0%] were men, 159 [94.6%] were White, 9 [6.4%] were of other race and ethnicity, including Asian and unknown ethnicity), with 81 in the minocycline group and 87 in the placebo group. The mean (SD) age was 46.1 (13.1) years, and the mean (SD) MADRS score at baseline was 26.5 (5.0). There was no difference in rates of completion between the minocycline (83.3% [70 of 81]) and the placebo group (83.1% [74 of 87]). Minocycline treatment did not alter the course of depression severity compared with placebo as assessed by a decrease in MADRS scores over 6 weeks of treatment (1.46 [-1.04 to 3.96], P = .25). Minocycline treatment also exhibited no statistically significant effect on secondary outcomes. Conclusions and Relevance: In this large randomized clinical trial with minocycline at a dose of 200 mg/d added to antidepressant treatment as usual for 6 weeks, minocycline was well tolerated but not superior to placebo in reducing depressive symptoms in patients with TRD. The results of this RCT emphasize the unmet need for therapeutic approaches and predictive biomarkers in TRD. Trial Registration: EU Clinical Trials Register Number: EudraCT 2015-001456-29.
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Trastorno Depresivo Resistente al Tratamiento , Minociclina , Antidepresivos/uso terapéutico , Depresión/tratamiento farmacológico , Trastorno Depresivo Resistente al Tratamiento/tratamiento farmacológico , Método Doble Ciego , Femenino , Humanos , Masculino , Minociclina/efectos adversos , Minociclina/uso terapéuticoRESUMEN
Background: Alzheimer's disease (AD) pathology is present many years before the onset of clinical symptoms. AD dementia cannot be treated. Timely and early detection of people at risk of developing AD is key for primary and secondary prevention. Moreover, understanding the underlying pathology that is present in the earliest stages of AD, and the genetic predisposition to that might contribute to the development of targeted disease-modifying treatments. Objectives: In this study, we aimed to explore whether genetic disposition to AD in asymptomatic individuals is associated with altered intrinsic functional connectivity as well as cognitive performance on neuropsychological tests. Methods: We examined 136 cognitively healthy adults (old group: mean age = 69.32, SD = 4.23; young group: mean age = 31.34, SD = 13.12). All participants had undergone resting-state functional magnetic resonance imagining (fMRI), DNA genotyping to ascertain polygenic risk scores (PRS), and neuropsychological testing for global cognition, working memory, verbal fluency, and executive functions. Results: Two-step hierarchical regression analysis revealed that higher PRS was significantly associated with lower scores in working memory tasks [Letter Number Span: ΔR 2 = 0.077 (p < 0.05); Spatial Span: ΔR 2 = 0.072 (p < 0.05)] in older adults (>60 years). PRS did not show significant modulations of the intrinsic functional connectivity of the posterior cingulate cortex (PCC) with other regions of interest in the brain that are affected in AD. Conclusion: Allele polymorphisms may modify the effect of other AD risk factors. This potential modulation warrants further investigations, particularly in cognitively healthy adults.
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Physical inactivity is discussed as one of the most detrimental influences for lifestyle-related medical complications such as obesity, heart disease, hypertension, diabetes and premature mortality in in- and outpatients with major depressive disorder (MDD). In contrast, intervention studies indicate that moderate-to-vigorous-intensity physical activity (MVPA) might reduce complications and depression symptoms itself. Self-reported data on depression [Beck-Depression-Inventory-II (BDI-II)], general habitual well-being (FAHW), self-esteem and physical self-perception (FAHW, MSWS) were administrated in a cross-sectional study with 76 in- and outpatients with MDD. MVPA was documented using ActiGraph wGT3X + ® accelerometers and fitness was measured using cardiopulmonary exercise testing (CPET). Subgroups were built according to activity level (low PA defined as MVPA < 30 min/day, moderate PA defined as MVPA 30-45 min/day, high PA defined as MVPA > 45 min/day). Statistical analysis was performed using a Mann-Whitney U and Kruskal-Wallis test, Spearman correlation and mediation analysis. BDI-II scores and MVPA values of in- and outpatients were comparable, but fitness differed between the two groups. Analysis of the outpatient group showed a negative correlation between BDI-II and MVPA. No association of inpatient MVPA and psychopathology was found. General habitual well-being and self-esteem mediated the relationship between outpatient MVPA and BDI-II. The level of depression determined by the BDI-II score was significantly higher in the outpatient low- and moderate PA subgroups compared to outpatients with high PA. Fitness showed no association to depression symptoms or well-being. To ameliorate depressive symptoms of MDD outpatients, intervention strategies should promote habitual MVPA and exercise exceeding the duration recommended for general health (≥ 30 min/day). Further studies need to investigate sufficient MVPA strategies to impact MDD symptoms in inpatient settings. Exercise effects seem to be driven by changes of well-being rather than increased physical fitness.
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Trastorno Depresivo Mayor , Ejercicio Físico , Autoimagen , Estudios Transversales , Trastorno Depresivo Mayor/psicología , Ejercicio Físico/psicología , Humanos , Análisis de MediaciónRESUMEN
The major depressive disorder is one of the most common mental illnesses worldwide. Current treatment standards recommend a combined therapy with medication and psychotherapy. As an additive component and to further improvements in treatment, physical activity such as yoga may be integrated into conventional treatment. This study investigates the impact of a 3-month body-oriented yoga in patients with major depressive disorder (MDD). In total, n = 83 patients were included. An intervention group received a vigorous Ashtanga-Yoga three times a week. The waiting-list control group obtained a treatment as usual (TAU). As a primary outcome depression scores (Beck Depression Inventory-II (BDI-II), Montgomery Asberg Depression Rating Scale (MADRS)) were tested at three time points. Secondary outcome was the positive and negative affect [Positive and Negative Affect Scale (PANAS)] and remission rates. To analyze the data, multilevel models and effect sizes were conducted. The results showed an improvement in BDI-II scores for both groups over time [γ = - 3.46, t(165) = - 7.99, p < 0.001] but not between groups [γ = 0.98, t(164) = 1.12, p = 0.263]. An interaction effect (time x group) occurred for MADRS [γ = 2.10, t(164) = 2.10, p < 0.038]. Positive affects improved over time for both groups [γ = 1.65, t(165) = 4.03, p < 0.001]. Negative affects decreased for all over time [γ = - 1.00, t(165) = - 2.51, p = 0.013]. There were no significant group differences in PANAS. Post hoc tests revealed a greater symptom reduction within the first 6 weeks for all measurements. The effect sizes for depression scores showed a positive trend. Remission rates indicated a significant improvement in the yoga group (BDI-II: 46.81%, MADRS: 17.02%) compared to the control group (BDI: 33.33%, MADRS: 8.33%). The findings suggest that there is a trendsetting additive effect of Ashtanga-Yoga after 3 months on psychopathology and mood with a greater improvement at the beginning of the intervention. Further research in this field can help to achieve more differentiated results.
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Trastorno Depresivo Mayor , Yoga , Trastorno Depresivo Mayor/terapia , Humanos , Resultado del Tratamiento , Yoga/psicologíaRESUMEN
BACKGROUND: Dietary lipids (omega-3 polyunsaturated fatty acids (n-3) PUFAs) and saturated fatty acids (SFA) seem to play an important role in brain health. (n-3) PUFAs have been shown to improve cerebral perfusion and to promote synaptogenesis. In this study, we investigated the relationship between dietary fat composition, cognitive performance and brain morphology in cognitively healthy individuals. METHODS: A total of 101 cognitively healthy participants (age: 42.3 ± 21.3 years, 62 females) were included in this study. Verbal memory was assessed using the California Verbal Learning Test (CVLT). Intake of (n-3) PUFA and SFA was calculated from food-frequency questionnaire-derived data (EPIC-FFQ). Magnetic resonance imaging (MRI) data were obtained (Siemens Trio 3T scanner) and grey matter volumes (GMV) were assessed by voxel-based morphometry (VBM/SPM8). We examined the association of SFA/(n-3) PUFA ratio and memory performance as well as GMV using regression models adjusted for age, sex, education, body mass index, apolipoprotein E (APOE) status and alcohol consumption. For VBM data, a multiple regression analysis was performed using the same covariates as mentioned before with intracranial volume as an additional covariate. RESULTS: A high SFA/(n-3) PUFA ratio was significantly (p < 0.05) correlated with poorer verbal memory performance and with lower GMV in areas of the left prefrontal cortex that support memory processes. CONCLUSIONS: These findings suggest that a diet rich in PUFAs is likely to exert favourable effects on brain morphology in brain areas important for memory and executive functions. This could constitute a possible mechanism for maintaining cognitive health in older age.
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Encéfalo/anatomía & histología , Cognición/fisiología , Grasas de la Dieta/análisis , Desempeño Psicomotor/fisiología , Adulto , Índice de Masa Corporal , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Estudios Transversales , Grasas de la Dieta/farmacología , Función Ejecutiva , Ácidos Grasos/administración & dosificación , Ácidos Grasos Insaturados/administración & dosificación , Femenino , Sustancia Gris/anatomía & histología , Sustancia Gris/diagnóstico por imagen , Voluntarios Sanos , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Memoria/fisiología , Persona de Mediana Edad , Pruebas Neuropsicológicas , Tamaño de los ÓrganosRESUMEN
INTRODUCTION: Major depressive disorder (MDD) and obesity are both common disorders associated with significant burden of disease worldwide. Importantly, MDD and obesity often co-occur, with each disorder increasing the risk for developing the other by about 50%-60%. Statins are among the most prescribed medications with well-established safety and efficacy. Statins are recommended in primary prevention of cardiovascular disease, which has been linked to both MDD and obesity. Moreover, statins are promising candidates to treat MDD because a meta-analysis of pilot randomised controlled trials has found antidepressive effects of statins as adjunct therapy to antidepressants. However, no study so far has tested the antidepressive potential of statins in patients with MDD and comorbid obesity. Importantly, this is a difficult-to-treat population that often exhibits a chronic course of MDD and is more likely to be treatment resistant. Thus, in this confirmatory randomised controlled trial, we will determine whether add-on simvastatin to standard antidepressant medication with escitalopram is more efficacious than add-on placebo over 12 weeks in 160 patients with MDD and comorbid obesity. METHODS AND ANALYSIS: This is a protocol for a randomised, placebo-controlled, double-blind multicentre trial with parallel-group design (phase II). One hundred and sixty patients with MDD and comorbid obesity will be randomised 1:1 to simvastatin or placebo as add-on to standard antidepressant medication with escitalopram. The primary outcome is change in the Montgomery-Åsberg Depression Rating Scale (MADRS) score from baseline to week 12. Secondary outcomes include MADRS response (defined as 50% MADRS score reduction from baseline), MADRS remission (defined as MADRS score <10), mean change in patients' self-reported Beck Depression Inventory (BDI-II) and mean change in high-density lipoprotein, low-density lipoprotein and total cholesterol from baseline to week 12. ETHICS AND DISSEMINATION: This protocol has been approved by the ethics committee of the federal state of Berlin (Ethik-Kommission des Landes Berlin, reference: 19/0226-EK 11) and by the relevant federal authority (Bundesinstitut für Arzneimittel und Medizinprodukte (BfArM), reference: 4043387). Study findings will be published in peer-reviewed journals and will be presented at (inter)national conferences. TRIAL REGISTRATION NUMBERS: NCT04301271, DRKS00021119, EudraCT 2018-002947-27.
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Trastorno Depresivo Mayor , Obesidad , Berlin , Citalopram/uso terapéutico , Depresión , Trastorno Depresivo Mayor/complicaciones , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/epidemiología , Método Doble Ciego , Humanos , Estudios Multicéntricos como Asunto , Obesidad/complicaciones , Obesidad/epidemiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Simvastatina/uso terapéutico , Resultado del TratamientoRESUMEN
Mild cognitive impairment (MCI) often precedes Alzheimer's Dementia (AD), and in a high proportion of individuals affected by MCI, there are already neuropathological processes ongoing that become more evident when patients progress to AD. Accordingly, there is a need for reliable biomarkers to distinguish between normal aging and incipient AD. Recent research suggests that, in addition to established biomarkers such as CSF Aß42, total tau and hyperphosphorylated tau, resting state connectivity established by functional magnetic resonance imaging might also be a feasible biomarker for prodromal stages of AD. In order to explore this possibility, we investigated resting state functional connectivity as well as cerebrospinal fluid (CSF) biomarker profiles in patients with MCI (n = 30; age 66.43 ± 7.06 years) and cognitively healthy controls (n = 38; age 66.89 ± 7.12 years). CSF Aß42, total tau and hyperphosphorylated tau concentrations were correlated with measures of cognitive performance (immediate and delayed recall, global cognition, processing speed). Moreover, MCI-related alterations in intrinsic functional connectivity within the default mode network were investigated using functional resting state MRI. As expected, MCI patients showed decreased CSF Aß42 and increased total tau concentrations. These alterations were associated with cognitive performance. However, there were no differences between MCI patients and cognitively healthy controls regarding intrinsic functional connectivity. In conclusion, our results indicate that CSF protein profiles seem to be more closely related to cognitive decline than alterations in resting state activity. Thus, resting state connectivity might not be a reliable biomarker for early stages of AD.
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Enfermedad de Alzheimer/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Encéfalo/fisiopatología , Disfunción Cognitiva/líquido cefalorraquídeo , Red Nerviosa/fisiopatología , Anciano , Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/líquido cefalorraquídeo , Disfunción Cognitiva/diagnóstico , Correlación de Datos , Progresión de la Enfermedad , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/líquido cefalorraquídeo , Valor Predictivo de las Pruebas , Valores de Referencia , Factores de Riesgo , Proteínas tau/líquido cefalorraquídeoRESUMEN
Memory impairments are a major characteristic of schizophrenia (SZ). In the current study, we used an associative memory task to test the hypothesis that SZ patients and first-degree relatives have altered functional patterns in comparison to healthy controls. We analyzed the fMRI activation pattern during the presentation of a face-name task in 27 SZ patients, 23 first-degree relatives, and 27 healthy controls. In addition, we performed correlation analyses between individual psychopathology, accuracy and reaction time of the task and the beta scores of the functional brain activations. We observed a lower response accuracy and increased reaction time during the retrieval of face-name pairs in SZ patients compared with controls. Deficient performance was accompanied by abnormal functional activation patterns predominantly in DMN regions during encoding and retrieval. No significant correlation between individual psychopathology and neuronal activation during encoding or retrieval of face-name pairs was observed. Findings of first-degree relatives indicated slightly different functional pattern within brain networks in contrast to controls without significant differences in the behavioral task. Both the accuracy of memory performance as well as the functional activation pattern during retrieval revealed alterations in SZ patients, and, to a lesser degree, in relatives. The results are of potential relevance for integration within a comprehensive model of memory function in SZ. The development of a neurophysiological model of cognition in psychosis may help to clarify and improve therapeutic options to improve memory and functioning in the illness.
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Based on accumulating evidence of a role of lipid signaling in many physiological and pathophysiological processes including psychiatric diseases, the present data driven analysis was designed to gather information needed to develop a prospective biomarker, using a targeted lipidomics approach covering different lipid mediators. Using unsupervised methods of data structure detection, implemented as hierarchal clustering, emergent self-organizing maps of neuronal networks, and principal component analysis, a cluster structure was found in the input data space comprising plasma concentrations of d = 35 different lipid-markers of various classes acquired in n = 94 subjects with the clinical diagnoses depression, bipolar disorder, ADHD, dementia, or in healthy controls. The structure separated patients with dementia from the other clinical groups, indicating that dementia is associated with a distinct lipid mediator plasma concentrations pattern possibly providing a basis for a future biomarker. This hypothesis was subsequently assessed using supervised machine-learning methods, implemented as random forests or principal component analysis followed by computed ABC analysis used for feature selection, and as random forests, k-nearest neighbors, support vector machines, multilayer perceptron, and naïve Bayesian classifiers to estimate whether the selected lipid mediators provide sufficient information that the diagnosis of dementia can be established at a higher accuracy than by guessing. This succeeded using a set of d = 7 markers comprising GluCerC16:0, Cer24:0, Cer20:0, Cer16:0, Cer24:1, C16 sphinganine, and LacCerC16:0, at an accuracy of 77%. By contrast, using random lipid markers reduced the diagnostic accuracy to values of 65% or less, whereas training the algorithms with randomly permuted data was followed by complete failure to diagnose dementia, emphasizing that the selected lipid mediators were display a particular pattern in this disease possibly qualifying as biomarkers.
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BACKGROUND: Working memory (WM) deficits in schizophrenia (SCZ) have been linked to impairments in the encoding phase that are associated with aberrant neuronal functioning. Similar abnormalities have been observed in unaffected first-degree relatives (REL) and are thus discussed as candidate endophenotypes. The process of WM consolidation - i.e. the formation of durable WM representations - is assumed to be impaired in SCZ, but no study has investigated WM consolidation and neuronal correlates of visual WM encoding in REL before. METHOD: We examined whole-brain activation during the encoding phase with an event-related functional magnetic resonance imaging study design in 25 SCZ subjects, 22 REL subjects, and 25 healthy controls. Subjects performed a visual masked change detection task that assessed WM performance and consolidation. RESULTS: SCZ showed deficient WM performance indicating an impairment consolidation process, accompanied by broad neuronal hypoactivation, most prominently in frontal brain regions, as well as increased activity of the anterior cingulate during the encoding phase. REL showed decreased neuronal activity in the middle and medial frontal gyrus and increased activity in the precentral gyrus and insula during encoding, but no significant behavioral deficits were observed. In respect of given consolidation times, REL showed a shift from decreased frontal activity at short time intervals to increased frontal activity at longer time intervals. CONCLUSIONS: Findings suggest WM consolidation may be slowed in REL so that the deployment of compensatory neuronal resources during encoding is needed to assure proper WM performance. This supports the view of WM-related neuronal dysfunctions as a potential endophenotypic marker.
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Endofenotipos , Giro del Cíngulo/fisiopatología , Consolidación de la Memoria/fisiología , Memoria a Corto Plazo/fisiología , Corteza Prefrontal/fisiopatología , Esquizofrenia/fisiopatología , Percepción Visual/fisiología , Adulto , Familia , Femenino , Neuroimagen Funcional , Giro del Cíngulo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Corteza Prefrontal/diagnóstico por imagenRESUMEN
Background: Bipolar disorder (BD) has been associated with distributed network disruption, but little is known on how different clinical subtypes, particularly those with an earlier and later onset of disease, are related to connectivity changes in white matter (WM) tracts. Methods: Diffusion tensor imaging (DTI) and volumetric measures were carried out in early-onset bipolar patients [(EOD) (n = 16)], late-onset bipolar disorder [(LOD)(n = 14)] and healthy controls (n = 32). We also computed ROI analysis of gray matter (GM) and white matter (WM) volumes using the regions with significant group differences in the DTI parameters. Cognitive and behavior measurements were analyzed between groups. Results: Lower fraction of anisotropy (FA) in the right hemisphere comprising anterior thalamic radiation, fornix, posterior cingulate, internal capsule, splenium of corpus callosum was observed in the LOD in comparison with EOD; additionally, lower FA was also found in the LOD in comparison with healthy controls, mostly in the right hemisphere and comprising fibers of the splenium of the corpus callosum, cingulum, superior frontal gyrus and posterior thalamic radiation; LOD also showed worse episodic memory performance than EOD; no statistical significant differences between mood symptoms, WM and GM volumes were found between BD groups. Conclusion: Even after correcting for age differences, LOD was associated with more extensive WM microstructural changes and worse episodic memory performance than EOD; these findings suggest that changes in the WM fiber integrity may be associated with a later presentation of BD, possibly due to mechanisms other than neuroprogression. However, these findings deserve replication in larger, prospective, studies.
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We investigated a possible link between bacterial infestation of the oral cavity, dental health and Alzheimer's dementia (AD). Resistant germs on the surface of the maxillary molars are the cause of a complex biofilm of bacteria with the effect of a colonization of germs between oral cavity and maxillary sinus. Bacterial toxins may lead to subsequent inflammatory processes transgressing to neighboring central nervous system structures that are suspected to be crucial in the inception of AD, such as the entorhinal cortex and the hippocampus.
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Envejecimiento/patología , Enfermedad de Alzheimer/microbiología , Toxinas Bacterianas/aislamiento & purificación , Encéfalo/microbiología , Placa Dental/microbiología , Periodontitis/microbiología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/tratamiento farmacológico , Antibacterianos/uso terapéutico , Encéfalo/patología , Placa Dental/diagnóstico , Placa Dental/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Periodontitis/diagnósticoRESUMEN
Neurodegenerative diseases may directly affect memory performance, thus leading to functional impairments. An increasing body of evidence suggests an association between dietary intake of omega-3 fatty acids and memory functioning in animal models as well as in human studies. Recent evidence supports a potential beneficial role of omega-3 fatty acid supplementation on psychopathological and cognitive symptoms, beside their established positive effects on cardiovascular health. OBJECTIVE: We summarize relevant and recent evidence from epidemiological, interventional and experimental studies investigating dietary consumption of omega-3 fatty acids and emphazing mechanisms of memory disorders, with a focus on mild cognitive impairment (MCI) and dementia. Omega-3 fatty acid could represent an affordable and accessible adjunctive treatment option to improve cognitive and non-cognitive function with a focus on MCI or dementia. However, apart from its translational promise, which is based on mechanistic models and evidence from animal studies, evidence for clinical benefits in humans is lacking. METHOD: To follow this research question, a search through electronic databases for the following search terms to identify relevant studies was conducted: 'omega 3 fatty acids', 'cognition', 'memory', ´Alzheimer´s Disease ´, ´dementia´, ´MCI`. Studies were included if they presented original data and were published in English between 1990 and 2015. RESULTS: To our the best of our knowledge, there are only 8 interventional studies that investigated the effects of n3-PUFAs in dementia patients, while 6 studies were conducted in healthy individuals, which in combination show equivocal results. CONCLUSION: This verifies the need for larger and (more) well designed clinical trials.
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Enfermedad de Alzheimer/dietoterapia , Disfunción Cognitiva/dietoterapia , Ácidos Grasos Omega-3 , Enfermedad de Alzheimer/psicología , Animales , Cognición , Disfunción Cognitiva/psicología , HumanosRESUMEN
Depression is a common neuropsychiatric manifestation among Alzheimer's disease (AD) patients. It may compromise everyday activities and lead to a faster cognitive decline as well as worse quality of life. The identification of promising biomarkers may therefore help to timely initiate and improve the treatment of preclinical and clinical states of AD, and to improve the long-term functional outcome. In this narrative review, we report studies that investigated biomarkers for AD-related depression. Genetic findings state AD-related depression as a rather complex, multifactorial trait with relevant environmental and inherited contributors. However, one specific set of genes, the brain derived neurotrophic factor (BDNF), specifically the Val66Met polymorphism, may play a crucial role in AD-related depression. Regarding neuroimaging markers, the most promising findings reveal structural impairments in the cortico-subcortical networks that are related to affect regulation and reward / aversion control. Functional imaging studies reveal abnormalities in predominantly frontal and temporal regions. Furthermore, CSF based biomarkers are seen as potentially promising for the diagnostic process showing abnormalities in metabolic pathways that contribute to AD-related depression. However, there is a need for standardization of methodological issues and for replication of current evidence with larger cohorts and prospective studies.
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Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/psicología , Depresión/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Animales , Biomarcadores/metabolismo , Encéfalo/diagnóstico por imagen , Depresión/complicaciones , Depresión/genética , HumanosRESUMEN
The European DTI Study on Dementia (EDSD) is a multicenter framework created to study the diagnostic accuracy and inter-site variability of DTI-derived markers in patients with manifest and prodromal Alzheimer's disease (AD). The dynamically growing database presently includes 493 DTI, 512 T1-weighted MRI, and 300 FLAIR scans from patients with AD dementia, patients with Mild Cognitive Impairment (MCI) and matched Healthy Controls, acquired on 13 different scanner platforms. The imaging data is publicly available, along with the subjects' demographic and clinical characterization. Detailed neuropsychological information, cerebrospinal fluid information on biomarkers and clinical follow-up diagnoses are included for a subset of subjects. This paper describes the rationale and structure of the EDSD, summarizes the available data, and explains how to gain access to the database. The EDSD is a useful database for researchers seeking to investigate the contribution of DTI to dementia diagnostics.
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Enfermedad de Alzheimer/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Bases de Datos Factuales , Imagen de Difusión Tensora , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Difusión de la Información , Masculino , Persona de Mediana EdadRESUMEN
Proteomic analyses facilitate the interpretation of molecular biomarker probes which are very helpful in diagnosing schizophrenia (SZ). In the current study, we attempt to test whether potential differences in plasma protein expressions in SZ and bipolar disorder (BD) are associated with cognitive deficits and their underlying brain structures. Forty-two plasma proteins of 29 SZ patients, 25 BD patients and 93 non-clinical controls were quantified and analysed using multiple reaction monitoring-based triple quadrupole mass spectrometry approach. We also computed group comparisons of protein expressions between patients and controls, and between SZ and BD patients, as well. Potential associations of protein levels with cognitive functioning (psychomotor speed, executive functioning, crystallised intelligence) as well as underlying brain volume in the hippocampus were explored, using bivariate correlation analyses. The main finding of this study was that apolipoprotein expression differed between patients and controls and that these alterations in both disease groups were putatively related to cognitive impairments as well as to hippocampus volumes. However, none of the protein level differences were related to clinical symptom severity. In summary, altered apolipoprotein expression in BD and SZ was linked to cognitive decline and underlying morphological changes in both disorders. Our results suggest that the detection of molecular patterns in association with cognitive performance and its underlying brain morphology is of great importance for understanding of the pathological mechanisms of SZ and BD, as well as for supporting the diagnosis and treatment of both disorders.
Asunto(s)
Apolipoproteínas C/metabolismo , Trastorno Bipolar/complicaciones , Trastorno Bipolar/patología , Trastornos del Conocimiento/etiología , Hipocampo/metabolismo , Esquizofrenia/complicaciones , Esquizofrenia/patología , Adulto , Proteínas Sanguíneas/metabolismo , Femenino , Humanos , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Estadística como AsuntoRESUMEN
BACKGROUND: In psychosis, white matter (WM) microstructural changes have been detected previously; however, direct comparisons of findings between bipolar (BD) and schizophrenia (SZ) patients are scarce. In this study, we employed deterministic tractography to reconstruct WM tracts in BD and SZ patients. METHODS: Diffusion tensor imaging (DTI) data was carried out with n=32 euthymic BD type I patients, n=26 SZ patients and 30 matched healthy controls. Deterministic tractography using multiple indices of diffusion (fractional anisotropy (FA), tract volume (Vol), tract length (Le) and number of tracts (NofT)) were obtained from the fornix, the cingulum, the anterior thalamic radiation, and the corpus callosum bilaterally. RESULTS: We showed widespread WM microstructural changes in SZ, and changes in the corpus callosum, the left cingulum and the fornix in BD. Fornix fiber tracking scores were associated with cognitive performance in SZ, and with age and age at disease onset in the BD patient group. LIMITATIONS: Although the influence of psychopharmacological drugs as biasing variables on morphological alterations has been discussed for SZ and BD, we did not observe a clear influence of drug exposure on our findings. CONCLUSIONS: These results confirm the assumption that SZ patients have more severe WM changes than BD patients. The findings also suggest a major role of WM changes in the fornix as important fronto-limbic connections in the etiology of cognitive symptoms in SZ, but not in BD.
Asunto(s)
Trastorno Bipolar/fisiopatología , Trastornos del Conocimiento/fisiopatología , Imagen de Difusión Tensora/métodos , Fórnix/fisiopatología , Esquizofrenia/fisiopatología , Sustancia Blanca/fisiopatología , Adulto , Trastorno Bipolar/complicaciones , Trastornos del Conocimiento/complicaciones , Femenino , Fórnix/diagnóstico por imagen , Humanos , Masculino , Esquizofrenia/complicaciones , Sustancia Blanca/diagnóstico por imagenRESUMEN
The apolipoprotein E (ApoE) É4 allele is a well-established genetic risk factor for sporadic Alzheimer's disease. Some evidence suggests a negative role of the ApoE É4 allele for cognitive performance in late life, while beneficial effects on cognition have been shown in young age. We investigated age-related effects of the ApoE gene on brain function by assessing cognitive performance, as well as functional activation patterns during retrieval of Face-Name pairs in a group of young (nâ=â50; age 26.4±4.6 years, 25 É4 carriers) and old (nâ=â40; age 66.1±7.0 years, 20 É4 carriers) participants. A cross-sectional factorial design was used to examine the effects of age, ApoE genotype, and their interaction on both cognitive performance and the blood oxygenation level dependent (BOLD) brain response during retrieval of Face-Name pairs. While there were no genotype-related differences in cognitive performance, we found a significant interaction of age and ApoE genotype on task-related activation bilaterally in anterior cingulate gyrus and superior frontal gyrus, as well as left and right insula. Old age was associated with increased activity in É4 carriers. The increased BOLD response in old É4 carriers during retrieval could indicate a neurocognitive disadvantage associated with the É4 allele with increasing age. Furthermore, recruitment of neuronal resources resulted in enhanced memory performance in young É4 carriers, pointing to a better neurofunctional capacity associated with the ApoE4 genotype in young age.