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1.
Alzheimers Dement ; 19(7): 2853-2864, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36588502

RESUMEN

BACKGROUND: Apathy is the most frequent neuropsychiatric symptom in patients with dementia of the Alzheimer's type (DAT). We analyzed the influence of apathy on the resource use of DAT patients and their caregivers. METHODS: Included were baseline data of 107 DAT patients from a randomized clinical trial on apathy treatment. The Resource Utilization in Dementia (RUD) instrument assessed costs over a 1-month period prior to baseline. Cost predictors were determined via a least absolute shrinkage and selection operator (LASSO). RESULTS: On average, total monthly costs were €3070, of which €2711 accounted for caregivers' and €359 for patients' costs. An increase of one point in the Apathy Evaluation Scale resulted in a 4.1% increase in total costs. DISCUSSION: Apathy is a significant cost driving factor for total costs in mild to moderate DAT. Effective treatment of apathy might be associated with reduced overall costs in DAT.


Asunto(s)
Enfermedad de Alzheimer , Apatía , Humanos , Enfermedad de Alzheimer/diagnóstico , Cuidadores/psicología , Resultado del Tratamiento
2.
BMC Geriatr ; 21(1): 222, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33794789

RESUMEN

BACKGROUND: Most people with dementia (PwD) are cared for at home, with general practitioners (GPs) playing a key part in the treatment. However, primary dementia care suffers from a number of shortcomings: Often, diagnoses are made too late and therapies by GPs do not follow the guidelines. In cases of acute crises, PwD are too often admitted to hospital with adverse effects on the further course of the disease. The aim of this study is to implement and evaluate a new GP-based, complex dementia care model, DemStepCare. DemStepCare aims to ensure demand-oriented, stepped care for PwD and their caregivers. METHODS/DESIGN: In a cluster randomized controlled trial, the care of PwD receiving a complex intervention, where the GP is supported by a multi-professional team, is compared to (slightly expanded) usual care. GPs are clustered by GP practice, with 120 GP practices participating in total. GP practices are randomized to an intervention or a control group. 800 PwD are to be included per group. Recruitment takes place in Rhineland-Palatinate, Germany. In addition, a second control group with at least 800 PwD will be formed using aggregated routine data from German health insurance companies. The intervention comprises the training of GPs, case management including repeated risk assessment of the patients' care situation, the demand-oriented service of an outpatient clinic, an electronic case record, external medication analyses and a link to regional support services. The primary aims of the intervention are to positively influence the quality of life for PwD, to reduce the caregivers' burden, and to reduce the days spent in hospital. Secondary endpoints address medication adequacy and GPs' attitudes and sensitivity towards dementia, among others. DISCUSSION: The GP-based dementia care model DemStepCare is intended to combine a number of promising interventions to provide a complex, stepped intervention that follows the individual needs of PwD and their caregivers. Its effectiveness and feasibility will be assessed in a formative and a summative evaluation. TRIAL REGISTRATION: German Register of Clinical Trials (Deutsches Register Klinischer Studien, DRKS), DRKS00023560 . Registered 13 November 2020 - Retrospectively registered. HTML&TRIAL_ID=DRKS00023560.


Asunto(s)
Demencia , Calidad de Vida , Cuidadores , Demencia/diagnóstico , Demencia/terapia , Alemania , Humanos , Atención Primaria de Salud , Ensayos Clínicos Controlados Aleatorios como Asunto
3.
Ann Rheum Dis ; 78(9): 1226-1234, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31186256

RESUMEN

OBJECTIVES: We explored the impact of circulating anti-N-methyl-D-aspartate receptor (NMDAR) antibodies on the severity of fatigue in patients with systemic lupus erythematosus (SLE). METHODS: Serum samples of 426 patients with SLE were analysed for the presence of antibodies to the NR2 subunit of the NMDAR. In parallel, the severity of fatigue was determined according to the Fatigue Scale for Motor and Cognitive functions questionnaire. In a subgroup of patients with SLE, the hippocampal volume was correlated with the levels of anti-NR2 antibodies. Isolated immunoglobulin G from patients with anti-NR2 antibodies were used for murine immunohistochemical experiments and functional assays on neuronal cell lines. Treatment effects were studied in 86 patients with lupus under belimumab therapy. RESULTS: We found a close correlation between the titre of anti-NR2 antibodies, the severity of fatigue, the clinical disease activity index (Systemic Lupus Erythematosus Disease Activity Index 2000) and anti-double stranded DNA antibodies-independently of the presence of neuropsychiatric lupus manifestations. Pathogenic effects could be demonstrated by (1) detection of anti-NR2 antibodies in the cerebrospinal fluid, (2) in situ binding of anti-NR2 antibodies to NMDAR of the hippocampus area and (3) distinct functional effects in vitro: downregulating the energy metabolism of neuronal cells without enhanced cytotoxicity. Treatment with belimumab for at least 6 months affected both the severity of fatigue and the levels of anti-NR2 antibodies. CONCLUSION: The presence of anti-NR2 antibodies in patients with SLE with fatigue is a helpful diagnostic tool and may offer a major approach in the therapeutic management of this important disabling symptom in patients with SLE.


Asunto(s)
Autoanticuerpos/inmunología , Fatiga/diagnóstico , Lupus Eritematoso Sistémico/complicaciones , Receptores de N-Metil-D-Aspartato/inmunología , Adolescente , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/uso terapéutico , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Fatiga/etiología , Fatiga/inmunología , Femenino , Humanos , Inmunosupresores/uso terapéutico , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Adulto Joven
4.
Mol Genet Metab ; 127(1): 86-94, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30987917

RESUMEN

BACKGROUND: Fabry disease is a rare, X-linked, lifelong progressive lysosomal storage disorder. Severely deficient α-galactosidase A activity in males is associated with the classic phenotype with early-onset, multisystem manifestations evolving to vital organ complications during adulthood. We assessed the ability of 2 low-dose agalsidase beta regimens to lower skin, plasma, and urine globotriaosylceramide (GL-3) levels, and influence clinical manifestations in male pediatric Fabry patients. METHODS: In this multicenter, open-label, parallel-group, phase 3b study, male patients aged 5-18 years were randomized to receive agalsidase beta at 0.5 mg/kg 2-weekly (n = 16) or 1.0 mg/kg 4-weekly (n = 15) for 5 years. All had plasma/urine GL-3 accumulation but no clinically evident organ involvement. The primary outcome was GL-3 accumulation in superficial skin capillary endothelium (SSCE). RESULTS: The mean age was 11.6 (range: 5-18) years and all but one of the 31 patients had classic GLA mutations. In the overall cohort, shifts from non-0 to 0-scores for SSCE GL-3 were significant at years 1, 3, and 5, but results were variable. Plasma GL-3 normalized and urine GL-3 reduced substantially. Higher anti-agalsidase beta antibody titers were associated with less robust SSCE GL-3 clearance and higher urine GL-3 levels. Renal function remained stable and normal. Most Fabry signs and symptoms tended to stabilize; abdominal pain was significantly reduced (-26.3%; P = .0215). No new clinical major organ complications were observed. GL-3 accumulation and cellular and vascular injury were present in baseline kidney biopsies (n = 7). Treatment effects on podocyte GL-3 content and foot process width were highly variable. Fabry arteriopathy overall increased in severity. Two patients withdrew and 2 had their agalsidase beta dose increased. CONCLUSIONS: Our findings increase the limited amount of available data on long-term effects of enzyme replacement therapy in pediatric, classic Fabry patients. The low-dose regimens studied here over a period of 5 years did not demonstrate a consistent benefit among the patients in terms of controlling symptomatology, urine GL-3 levels, and pathological histology. The current available evidence supports treatment of pediatric, classic male Fabry patients at the approved agalsidase beta dose of 1.0 mg/kg 2-weekly if these patients are considered for enzyme replacement therapy with agalsidase beta.


Asunto(s)
Terapia de Reemplazo Enzimático/estadística & datos numéricos , Enfermedad de Fabry/tratamiento farmacológico , Isoenzimas/uso terapéutico , alfa-Galactosidasa/uso terapéutico , Adolescente , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Humanos , Masculino , Piel/química , Piel/patología , Resultado del Tratamiento , Trihexosilceramidas/análisis
5.
Int J Geriatr Psychiatry ; 34(4): 588-593, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30588672

RESUMEN

OBJECTIVES: To determine whether the Mini-Cog can be applied by nursing staff to hospitalized elderly patients for cognitive impairment associated risk stratification. METHODS: This explorative prospective multicenter cohort study was carried out among 2522 patients aged 70 and older, hospitalized due to physical illness in eight hospitals in Rhineland-Palatinate, Germany. All patients were asked to conduct the Mini-Cog at the day of admission and were clustered into low-performance, intermediate-performance, and good-performance categories by trained nursing staff and two experienced geronto-psychiatrists as gold standard. Complications in the course of the treatment were monitored. RESULTS: The Mini-Cog was conducted in 1398 (54%) out of 2522 eligible patients. Mini-Cog scores assessed by nursing staff differed from the gold standard in 327 cases (23.9%). According to the area under the curve (AUC), nursing staff identified cognitively low-performing patients almost as well as the geronto-psychiatrists (AUC = 0.862; 95% CI, 0.83-0.89; P < 0.001, accuracy 89.6%). Overall, 241 (17.6%) patients were classified as low performing. These patients had a significantly higher probability of suffering from at least one complication (odds ratio [OR] = 3.13; 95% CI, 2.09-4.70; calculated by a logistic regression model, adjusted for age), and they had a higher probability to show behavioral symptoms. CONCLUSION: Even under naturalistic conditions, nursing staff detected cognitively low-performing inpatients with the Mini-Cog. Using this short screening instrument should enable to predict complications of hospitalized older patients associated with cognitive impairment, a precondition to implement targeted care for this vulnerable patient group.


Asunto(s)
Disfunción Cognitiva , Tamizaje Masivo , Pruebas de Estado Mental y Demencia , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Cognición , Disfunción Cognitiva/diagnóstico , Estudios de Cohortes , Estudios de Factibilidad , Femenino , Alemania , Hospitalización , Hospitales , Humanos , Pacientes Internos , Masculino , Oportunidad Relativa , Estudios Prospectivos
6.
Int Psychogeriatr ; 31(3): 383-391, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30221613

RESUMEN

ABSTRACTObjectives:Dementia and cognitive impairment are associated with higher rates of complications and mortality during hospitalization in older patients. Moreover, length of hospital stay and costs are increased. In this prospective cohort study, we investigated the frequency of hospitalizations caused by ambulatory care-sensitive conditions (ACSCs), for which proactive ambulatory care might prevent the need for a hospital stay, in older patients with and without cognitive impairments. DESIGN: Prospective cohort study. SETTING: Eight hospitals in Germany. PARTICIPANTS: A total of 1,320 patients aged 70 years and older. MEASUREMENTS: The Mini-Cog test has been used to assess cognition and to categorize patients in the groups no/moderate cognitive impairments (probably no dementia) and severe cognitive impairments (probable dementia). Moreover, lengths of hospital stay and complication rates have been assessed, using a binary questionnaire (if occurred during hospital stay or not; behavioral symptoms were adapted from the Cohen-Mansfield Agitation Inventory). Data have been acquired by the nursing staff who received a special multi-day training. RESULTS: Patients with severe cognitive impairments showed higher complication rates (including incontinence, disorientation, irritability/aggression, restlessness/anxiety, necessity of Tranquilizers and psychiatric consults, application of measures limiting freedom, and falls) and longer hospital stays (+1.4 days) than patients with no/moderate cognitive impairments. Both groups showed comparably high ACSC-caused admission rates of around 23%. CONCLUSIONS: The study indicates that about one-fourth of hospital admissions of cognitively normal and impaired older adults are caused by ACSCs, which are mostly treatable on an ambulatory basis. This implies that an improved ambulatory care might reduce the frequency of hospitalizations, which is of particular importance in cognitively impaired elderly due to increased complication rates.


Asunto(s)
Atención Ambulatoria/métodos , Disfunción Cognitiva/terapia , Demencia/terapia , Hospitalización/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Disfunción Cognitiva/psicología , Demencia/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
Z Gerontol Geriatr ; 52(7): 661-666, 2019 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-30478791

RESUMEN

BACKGROUND: It is regularly criticized that the diagnostics of dementia are not used effectively and consistently enough in general practitioner (GP) care. An important component for the optimization of early detection is the targeted training and involvement of the practice staff. To date, there is a lack of studies that capture the extent to which primary care personnel are actually integrated into dementia recognition and how they assess their own potential to contribute to a more efficient diagnosis of dementia. MATERIAL AND METHODS: The study was based on 45 qualitative individual interviews with GP practice personnel in Rhineland-Palatinate and Hesse, which were conducted orally and personally between November 2017 and June 2018 (duration: 25-70 min). RESULTS: The results show that GP personnel showed a great willingness to support the family doctor in dementia recognition and diagnostics; however, this potential is only partly used in primary care practices. Most of the sample showed marked uncertainties in assessing possible signs of incipient dementia. This corresponds to the fact that only a minority of the interviewees had ever completed training in which dementia was an important topic. The identification of dementia patients by the practice employees seems to function according to the random principle and less according to systematic criteria. CONCLUSION: The analysis showed that many GPs are not yet aware of the opportunities offered by a greater involvement of practice personnel in the recognition of dementia. Accordingly, GPs should be advised of the benefits of such a solution. At the same time, more attention should be paid to low-threshold training formats, which are tailored specifically to the perspective of practice employees and convey important dementia-specific diagnostics, action and communication skills.


Asunto(s)
Demencia , Médicos Generales , Actitud del Personal de Salud , Demencia/diagnóstico , Medicina General/estadística & datos numéricos , Médicos Generales/estadística & datos numéricos , Humanos , Atención Primaria de Salud/estadística & datos numéricos
8.
Cereb Cortex ; 27(3): 1841-1848, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26879092

RESUMEN

The basal forebrain cholinergic system (BFCS) is the major source of acetylcholine for the cerebral cortex in humans. The aim was to analyze the pattern of BFCS and cortical atrophy in MCI patients to find evidence for a parallel atrophy along corticotopic organization of BFCS projections. BFCS volume and cortical thickness were analyzed using high-definition 3D structural magnetic resonance imaging data from 1.5-T and 3.0-T scanners of 64 MCI individuals and 62 cognitively healthy elderly controls from the European DTI study in dementia. BFCS volume reduction was correlated with thinning of cortical areas with known BFCS projections, such as Ch2 and parahippocampal gyrus in the MCI group, but not in the control group. Additionally, we found correlations between BFCS and cortex atrophy beyond the known corticotopic projections, such as between Ch4p and the cingulate gyrus. BFCS volume reduction was associated with regional thinning of cortical areas that included, but was not restricted to, the pattern of corticotopic projections of the BFCS as derived from animal studies. Our in vivo results may indicate the existence of more extended projections from the BFCS to the cerebral cortex in humans than that known from prior studies with animals.


Asunto(s)
Disfunción Cognitiva/diagnóstico por imagen , Prosencéfalo/diagnóstico por imagen , Acetilcolina/metabolismo , Anciano , Péptidos beta-Amiloides/líquido cefalorraquídeo , Atrofia , Biomarcadores/líquido cefalorraquídeo , Disfunción Cognitiva/metabolismo , Femenino , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Masculino , Escala del Estado Mental , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/metabolismo , Tamaño de los Órganos , Prosencéfalo/metabolismo
9.
Neuroimage ; 144(Pt B): 305-308, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27046114

RESUMEN

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.


Asunto(s)
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 Edad
10.
Hum Brain Mapp ; 36(10): 3819-31, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26108449

RESUMEN

Hippocampal atrophy in advanced healthy aging has frequently been reported. However, the vulnerability of different hippocampal subfields to age-related atrophy is still a source of debate. Moreover, the association of age with the microstructural integrity of subfields is largely unknown. In this study, we investigated the associations between age and volume as well as microstructural integrity of hippocampal subfields using a three-dimensional (3D) surface mapping approach. Forty-three healthy older adults spanning the age range from 60 to 85 years underwent T1-weighted and diffusion-tensor imaging. Analyses demonstrated an association of age with hippocampal volume predominantly in the most anterior part of the hippocampal head, mainly corresponding to the subiculum. In contrast, the association of age with hippocampal microstructural integrity was mainly confined to regions located in the hippocampal body and tail, corresponding to the subiculum and CA1. Results indicate that age-related volumetric and microstructural alterations within hippocampal subfields provide complementary information and reflect different age-related processes. Potential mechanisms underlying the differential associations of age with volume and microstructure of hippocampal subfields are discussed.


Asunto(s)
Envejecimiento/fisiología , Hipocampo/anatomía & histología , Hipocampo/crecimiento & desarrollo , Anciano , Anciano de 80 o más Años , Mapeo Encefálico , Región CA1 Hipocampal/anatomía & histología , Región CA1 Hipocampal/crecimiento & desarrollo , Imagen de Difusión Tensora , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
11.
Ther Drug Monit ; 37(3): 353-61, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25384119

RESUMEN

BACKGROUND: Aiming to verify that therapeutic drug monitoring has the potential to optimize treatment with acetylcholine esterase inhibitors of patients with Alzheimer dementia, this study investigated whether serum concentrations of donepezil are associated with clinical improvement. METHODS: Clinical improvement was measured using the clinical global impression (CGI) scale, and donepezil concentrations were measured in serum by a high-performance liquid chromatographic method with spectrophotometric detection. RESULTS: In total, 206 serum samples from 106 patients (49.5% female) were retrospectively available for analysis. Patients included were treated under everyday conditions. Their mean ± SD age was 72 ± 9 years, daily doses of donepezil were 5 and 10 mg, and their mean ± SD serum concentrations were 23 ± 9 and 47 ± 18 ng/mL, respectively. Serum concentrations correlated significantly (P < 0.001) with CGI scores (Pearson's correlation coefficient r = 0.511, P < 0.01). In patients who were "very much improved," according to their CGI score, the mean serum concentration was 66 ± 20 ng/mL and thus significantly higher (P < 0.01) than in patients with "minimal improvement" (29 ± 12 ng/mL). Receiver operating characteristics analysis suggests that donepezil serum concentrations of at least 50 ng/mL may be recommended for maximal clinical benefit. CONCLUSIONS: Because donepezil serum concentrations were highly variable between individual patients and the majority of patients exhibited concentrations that were below 50 ng/mL at therapeutic doses of 5 and 10 mg/d, it can be concluded that therapeutic drug monitoring may be used to enhance the effectiveness of donepezil treatment.


Asunto(s)
Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/tratamiento farmacológico , Monitoreo de Drogas/métodos , Indanos/sangre , Indanos/uso terapéutico , Piperidinas/sangre , Piperidinas/uso terapéutico , Anciano , Inhibidores de la Colinesterasa/sangre , Inhibidores de la Colinesterasa/uso terapéutico , Donepezilo , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
12.
Alzheimers Dement ; 11(2): 175-83, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25616957

RESUMEN

BACKGROUND: The European Alzheimer's Disease Consortium and Alzheimer's Disease Neuroimaging Initiative (ADNI) Harmonized Protocol (HarP) is a Delphi definition of manual hippocampal segmentation from magnetic resonance imaging (MRI) that can be used as the standard of truth to train new tracers, and to validate automated segmentation algorithms. Training requires large and representative data sets of segmented hippocampi. This work aims to produce a set of HarP labels for the proper training and certification of tracers and algorithms. METHODS: Sixty-eight 1.5 T and 67 3 T volumetric structural ADNI scans from different subjects, balanced by age, medial temporal atrophy, and scanner manufacturer, were segmented by five qualified HarP tracers whose absolute interrater intraclass correlation coefficients were 0.953 and 0.975 (left and right). Labels were validated as HarP compliant through centralized quality check and correction. RESULTS: Hippocampal volumes (mm(3)) were as follows: controls: left = 3060 (standard deviation [SD], 502), right = 3120 (SD, 897); mild cognitive impairment (MCI): left = 2596 (SD, 447), right = 2686 (SD, 473); and Alzheimer's disease (AD): left = 2301 (SD, 492), right = 2445 (SD, 525). Volumes significantly correlated with atrophy severity at Scheltens' scale (Spearman's ρ = <-0.468, P = <.0005). Cerebrospinal fluid spaces (mm(3)) were as follows: controls: left = 23 (32), right = 25 (25); MCI: left = 15 (13), right = 22 (16); and AD: left = 11 (13), right = 20 (25). Five subjects (3.7%) presented with unusual anatomy. CONCLUSIONS: This work provides reference hippocampal labels for the training and certification of automated segmentation algorithms. The publicly released labels will allow the widespread implementation of the standard segmentation protocol.


Asunto(s)
Algoritmos , Hipocampo/patología , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Atrofia , Disfunción Cognitiva/patología , Femenino , Lateralidad Funcional , Hipocampo/anatomía & histología , Humanos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/instrumentación , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Reproducibilidad de los Resultados , Lóbulo Temporal/patología
13.
Alzheimers Dement ; 11(2): 111-25, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25267715

RESUMEN

BACKGROUND: An international Delphi panel has defined a harmonized protocol (HarP) for the manual segmentation of the hippocampus on MR. The aim of this study is to study the concurrent validity of the HarP toward local protocols, and its major sources of variance. METHODS: Fourteen tracers segmented 10 Alzheimer's Disease Neuroimaging Initiative (ADNI) cases scanned at 1.5 T and 3T following local protocols, qualified for segmentation based on the HarP through a standard web-platform and resegmented following the HarP. The five most accurate tracers followed the HarP to segment 15 ADNI cases acquired at three time points on both 1.5 T and 3T. RESULTS: The agreement among tracers was relatively low with the local protocols (absolute left/right ICC 0.44/0.43) and much higher with the HarP (absolute left/right ICC 0.88/0.89). On the larger set of 15 cases, the HarP agreement within (left/right ICC range: 0.94/0.95 to 0.99/0.99) and among tracers (left/right ICC range: 0.89/0.90) was very high. The volume variance due to different tracers was 0.9% of the total, comparing favorably to variance due to scanner manufacturer (1.2), atrophy rates (3.5), hemispheric asymmetry (3.7), field strength (4.4), and significantly smaller than the variance due to atrophy (33.5%, P < .001), and physiological variability (49.2%, P < .001). CONCLUSIONS: The HarP has high measurement stability compared with local segmentation protocols, and good reproducibility within and among human tracers. Hippocampi segmented with the HarP can be used as a reference for the qualification of human tracers and automated segmentation algorithms.


Asunto(s)
Hipocampo/patología , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Anciano , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Atrofia , Femenino , Lateralidad Funcional , Humanos , Imagenología Tridimensional/métodos , Internet , Imagen por Resonancia Magnética/instrumentación , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Reproducibilidad de los Resultados
14.
Hum Brain Mapp ; 35(5): 2448-58, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24038539

RESUMEN

The Stroop interference task is a widely used paradigm to examine cognitive inhibition, which is a key component of goal-directed behavior. With increasing age, reaction times in the Stroop interference task are usually slowed. However, to date it is still under debate if age-related increases in reaction times are merely an artifact of general slowing. The current study was conducted to investigate the role of general slowing, as measured by Trail-Making-Test-A, in age-related alterations of Stroop interference. We applied Diffusion Tensor Imaging (DTI) to determine the topography of neuronal networks underlying Stroop interference under control of general slowing. On the behavioral level, linear regression analysis demonstrated that age accounted for significant variance on Stroop interference, whereas TMT-A performance did not. Controlling for TMT-A, DTI based white matter analyses demonstrated a strong association of Stroop interference with integrity measures of genu of corpus callosum, bilateral anterior corona radiata, and bilateral anterior limb of capsula interna. These pathways are associated with frontal brain regions by either connecting the bilateral dorsolateral prefrontal cortex or the anterior cingulate cortex with frontal and subcortical regions or by containing fibers which are part of cortico-thalamic circuits that cross prefrontal regions. Importantly, results expand our knowledge of the neural basis of Stroop interference and emphasize the importance of white matter integrity of frontal pathways in the modulation of Stroop interference. Combining behavioral and DTI findings our results further suggest that cognitive inhibition, as measured by Stroop task, is a qualitatively distinct cognitive process that declines with age.


Asunto(s)
Envejecimiento , Mapeo Encefálico , Cognición/fisiología , Test de Stroop , Sustancia Blanca/anatomía & histología , Adulto , Anciano , Anciano de 80 o más Años , Imagen de Difusión Tensora , Femenino , Giro del Cíngulo , Humanos , Procesamiento de Imagen Asistido por Computador , Inhibición Psicológica , Masculino , Persona de Mediana Edad , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Adulto Joven
15.
Hum Brain Mapp ; 35(1): 309-18, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22965837

RESUMEN

Although cognitive training usually improves cognitive test performance, the capability to transfer these training gains into respective or functionally related cognitive domains varies significantly. Since most studies demonstrate rather limited transfer effects in older adults, aging might be an important factor in transfer capability differences. This study investigated the transfer capability of logical reasoning training gains to a measure of Fluid Intelligence (Gf) in relation to age, general intelligence, and brain structural integrity as measured by diffusion tensor imaging. In a group of 41 highly educated healthy elderly, 71% demonstrated successful transfer immediately after a 4-week training session (i.e. short-term transfer). In a subgroup of 22% of subjects transfer maintained over a 3-month follow-up period (i.e. long-term transfer). While short-term transfer was not related to structural integrity, long-term transfer was associated with increased structural integrity in corpus and genu of the corpus callosum. Since callosal structural integrity was also related to age (in the present and foregoing studies), previously observed associations between age and transfer might be moderated by the structural integrity. Surprisingly, age was not directly associated with transfer in this study which could be explained by the multi-dependency of the structural integrity (modulating factors beside age, e.g. genetics). In this highly educated sample, general intelligence was not related to transfer suggesting that high intelligence is not sufficient for transfer in normal aging. Further studies are needed to reveal the interaction of transfer, age, and structural integrity and delineate mechanisms of age-dependent transfer capabilities.


Asunto(s)
Envejecimiento , Cuerpo Calloso/anatomía & histología , Inteligencia/fisiología , Transferencia de Experiencia en Psicología/fisiología , Anciano , Anciano de 80 o más Años , Imagen de Difusión Tensora , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad
16.
Cerebrovasc Dis ; 38(6): 448-56, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25502511

RESUMEN

BACKGROUND: The central nervous system manifestations in Fabry disease (FD) include progressive white matter lesions (WMLs) and stroke. Due to progressive microvascular involvement, men and women with FD over 35 years of age develop WMLs. Moreover, the prevalence of stroke has been estimated to be 12 times higher in FD compared with the general population. Enzyme replacement therapy (ERT) is available and has shown beneficial effects on renal, cardiac, and peripheral nerve function in FD, but the ERT effect on the progression of WMLs, or the reduction in cerebrovascular events, remains unknown. METHODS: The WML burden and the effect of agalsidase beta 1 mg/kg biweekly on WML progression were assessed longitudinally in a Phase 4 agalsidase-beta placebo-controlled analysis of untreated and treated FD patients with mild-to-moderate renal involvement (serum creatinine measurements of ≥1.2 mg/dl and <3.0 mg/dl). The primary end point was the difference in the number of patients with increased WML burden between the agalsidase beta and placebo groups at the end of treatment. The diameters of the WMLs were determined manually using axial flow-attenuated-inversion-recovery-weighted magnetic resonance imaging (MRI) scans taken at baseline and follow-up. RESULTS: MRI scans from 41 FD patients (mean age 43.9, age range 20-68, 3 females; n=25 on ERT, n=16 on placebo) were analyzed. WML burden was present in 63% of patients at baseline, increased over a mean of 27 months (range 12-33 months) follow-up, and correlated with left ventricular hypertrophy (LVPW). Patients with previous or recent strokes (n=11, 39-68 years) showed an increase in the number of WMLs (p=0.005). A greater proportion of younger patients (≤50 years) on ERT (n=18) had stable WML burden compared with younger patients in the placebo group (n=13): 44% (8 of 18) versus 31% (4 of 13), p=0.014. The number needed to treat was 8. CONCLUSIONS: This FD patient cohort, with mild-to-moderate renal involvement, had a significant WML burden and high inter-individual variability associated with the degree of LVPW but not the degree of kidney dysfunction. These advanced patients with increased LVPW and stroke evidence may have had a higher cerebrovascular risk. The WML burden in patients on ERT was more likely to remain stable, compared with patients on placebo. Thus, ERT may reduce the progression of vascular disease, even in advanced FD patients, suggesting that early treatment may stabilize WML progression and stroke risk.


Asunto(s)
Terapia de Reemplazo Enzimático , Enfermedad de Fabry/tratamiento farmacológico , Isoenzimas/uso terapéutico , Leucoencefalopatías/tratamiento farmacológico , Sustancia Blanca/patología , alfa-Galactosidasa/uso terapéutico , Adulto , Anciano , Encéfalo/patología , Progresión de la Enfermedad , Enfermedad de Fabry/complicaciones , Enfermedad de Fabry/patología , Femenino , Humanos , Leucoencefalopatías/etiología , Leucoencefalopatías/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Adulto Joven
17.
Alzheimers Dement ; 10(3): 401-4, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23706516

RESUMEN

BACKGROUND: In this multicenter study, we investigated a possible association between the APOE ε4 allele and white matter (WM) integrity in Alzheimer's disease (AD) using diffusion tensor imaging (DTI). METHODS: We analyzed fractional anisotropy (FA) and mean diffusivity (MD) as indices of WM integrity in 70 AD patients (35 APOE ε4 carriers, 35 noncarriers) and 56 healthy control (HC) subjects (28 APOE ε4 carriers, 28 noncarriers). APOE ε4 carriers and noncarriers were matched for age and gender within each diagnostic group. RESULTS: We found significant effects of diagnosis (Pcorrected < .05 [FWE]; i.e., smaller FA values and larger MD values in AD patients compared with HCs) and significant effects (P < .001) of APOE ε4 carrier status on MD in HCs but not in AD subjects. CONCLUSIONS: The results indicate that APOE ε4 has a moderate effect on WM integrity in HCs, but no effect on WM integrity in manifest AD.


Asunto(s)
Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Apolipoproteína E4/genética , Encéfalo/patología , Sustancia Blanca/patología , Anciano , Anciano de 80 o más Años , Anisotropía , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora , Femenino , Genotipo , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad
18.
Alzheimers Dement ; 10(6): 684-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24857233

RESUMEN

New diagnostic criteria for Alzheimer's disease (AD) treat different biomarkers of neuronal injury as equivalent. Here, we quantified the degree of agreement between hippocampal volume on structural magnetic resonance imaging, regional glucose metabolism on positron emission tomography, and levels of phosphorylated tau in cerebrospinal fluid (CSF) in 585 subjects from all phases of the AD Neuroimaging Initiative. The overall chance-corrected agreement was poor (Cohen κ, 0.24-0.34), in accord with a high rate of conflicting findings (26%-41%). Neither diagnosis nor APOE ε4 status significantly influenced the distribution of agreement between the biomarkers. The degree of agreement tended to be higher in individuals with abnormal versus normal CSF ß-amyloid (Aß1-42) levels. Prospective diagnostic criteria for AD should address the relative importance of markers of neuronal injury and elaborate a way of dealing with conflicting biomarker findings.


Asunto(s)
Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/patología , Biomarcadores/líquido cefalorraquídeo , Hipocampo/patología , Proteínas tau/líquido cefalorraquídeo , Anciano , Apolipoproteínas E/genética , Atrofia/etiología , Distribución de Chi-Cuadrado , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Femenino , Fluorodesoxiglucosa F18 , Hipocampo/diagnóstico por imagen , Humanos , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Tomografía de Emisión de Positrones
19.
Neuropsychologia ; 193: 108761, 2024 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-38104856

RESUMEN

The corpus callosum (CC) has been identified as an important structure in the context of cognitive aging (Fling et al., 2011). Interhemispheric transfer time (IHTT) is regularly used in order to estimate interhemispheric integration enabled by the CC (Marzi, 2010; Nowicka and Tacikowski, 2011). However, only little is known with regards to the relationship between IHTT and the structural properties of the CC with only few studies with specific samples and methods available (Whitford et al., 2011). Thus, the present study aimed at investigating this relationship applying an event-related potentials (ERP) based approach of estimating IHTT as well as diffusion weighted imaging (DWI) with fractional anisotropy (FA) as an indicator of white matter integrity (WMI) of the genu, corpus and splenium of the CC. 56 healthy older adults performed a Dimond Task while ERPs were recorded and underwent DWI scanning. IHTT derived from posterior electrode sites correlated significantly with FA of the splenium (r = -0.286*, p = .03) but not the corpus (r = -0.187, p = .08) or genu (r = -0.189, p = .18). The present results support the notion that IHTT is related to WMI of the posterior CC. It may be concluded that ERP based IHTT is a suitable indicator of CC structure and function, however, likely specific to the interhemispheric transfer of visual information. Future studies may wish to confirm these findings in a more divers sample further exploring the precise interrelation between IHTT and structural or functional properties of the CC.


Asunto(s)
Cuerpo Calloso , Sustancia Blanca , Humanos , Anciano , Cuerpo Calloso/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Potenciales Evocados , Imagen de Difusión por Resonancia Magnética , Anisotropía
20.
Psychiatr Prax ; 2024 Apr 12.
Artículo en Alemán | MEDLINE | ID: mdl-38608668

RESUMEN

OBJECTIVE: The innovation fund project DemStepCare aimed to optimize multi-professional care through case management, risk stratification, and crisis outpatient clinic. Here, the evaluation results from the perspective of the general practitioners are presented. METHODS: A quantitative survey was carried out at three time points regarding acceptance, benefit assessment and sensitivity to dementia of the general practitioners. In addition, qualitative interviews were conducted. RESULTS: Satisfaction with the overall project was high. Added value and relief factors were perceived and more effective and stable dementia care was achieved through collaboration with case management. Physicians reported increased subjective competence in diagnostics and disease management. CONCLUSIONS: The results confirm the benefit and effectiveness of DemStepCare from general practitioner's perspective.

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