40 research outputs found
Mecanismos fisiopatólogicos del Trastorno de control de Impulsos en la enfermedad de Parkinson
276 p.La presente tesis se ha centrado en el estudio de los mecanismos fisiopatológicos del trastorno de control de impulsos (TCI) en pacientes con enfermedad de Parkinson (EP). El TCI es una complicación relevante ya que es frecuente y grave en muchas ocasiones, comportando una elevada disrupción de la vida del paciente y su entorno que puede llevar hasta al suicidio en los casos más graves. A pesar de las importantes repercusiones, sus mecanismos fisiopatológicos son desconocidos, habiéndose descrito resultados contradictorios a múltiples niveles de estudio, pero especialmente en los estudios de imagen. Esta tesis se ha realizado no sólo con el ánimo de comprender los mecanismos por los que ocurre, sino también con el objetivo de ampliar las herramientas de detección de los sujetos que serán más sensibles al desarrollo de esta complicación tras el inicio de la terapia de reposición dopaminérgica. Por este motivo, se ha realizado en estos pacientes una aproximación multimodal de neuroimagen desde diversas técnicas, con el objetivo de entender la interacción entre el impacto de la degeneración dopaminérgica y elreemplazo terapéutico en aspectos críticos del comportamiento humano, contribuyendo a delinear los posibles correlatos neurales relacionados con esta complicación en los pacientes con EP. El hecho de investigar y profundizar en los circuitos cerebrales que se encuentran alterados en este tipo de pacientes, podría abrir una puerta a la hora de tratar esta complicación una vez establecida, quizá fundamentando las bases de la terapia con ECP con electrodos direccionales y otros tratamientos focalizados en áreas pertenecientes al circuito límbico. Este trabajo también contribuiría al descubrimiento de biomarcadores de neuroimagen que pudiesen identificar pacientes con EP susceptibles de desarrollar un TCI, con el objetivo de su prevención evitando terapias con agonistas dopaminérgicos en dichos casos. Esta tesis se divide en tres subapartados en las que en (i) el primero estudiamos el patrón de denervación dopaminérgica de estos pacientes así como su asociación con el metabolismo cerebral y con diferentes características clínicas y cognitivas. Esto ha dado lugar a un artículo ya publicado en Eur J Nucl Med Mol Imaging. (ii) En segundo lugar se ha investigado la conectividad funcional dinámica en la Resonancia Magnética funcional en reposo en estos pacientes así como las propiedades topológicas de la misma mediante un análisis de teoría de grafos. Este artículo está actualmente en revisión por la revista Parkinsonism and related disorders journal. (iii) Por último en estos pacientes se ha estudiado la activación cerebral, el curso temporal de la misma y la mediación de la conectividad funcional mientras estos pacientes se enfrentaban en la Resonancia Magnética funcional al Juego de Azar de Iowa, una tarea de toma de decisiones y de control inhibitorio.Resumiendo los resultados: el estudio de la denervación dopaminérgica estriatal, muestra en estos pacientes una denervación dopaminérgica en el estriado ventral característica, paralela a la gravedad de su sintomatología y en asociación directa con una disminución de metabolismo cerebral en áreas pertenecientes al sistema mesocorticolimbico en reposo. Además se ha estudiado por primera vez la dinámica de la conectividad funcional también en reposo, en la que se aprecia que las alteraciones de estos pacientes exceden una disfunción en regiones cerebrales localizadas y se extienden a nivel de la comunicación entre redes, presentando una tendencia a mostrar un aumento de la conectividad funcional a nivel local en áreas concretas que intervienen en la evaluación del estímulo a expensas de una tendencia a reducir la conectividad a larga distancia. Este aumento del mantenimiento en este patrón de conectividad concreto, se asocia en estos pacientes tanto al aumento de impulsividad como a la mayor búsqueda de novedad como rasgo de personalidad del sujeto. De la misma manera, el estudio de las propiedades topológicas de estas alteraciones en la conectividad de estos pacientes, nos muestra una elevada eficiencia local en la comunicación entre estas áreas. Estos resultados nos muestran patrones específicos de estos pacientes en reposo, tanto a nivel molecular como de Resonancia Magnética funcional, que se hacen más patentes conforme se acentúa la gravedad del TCI, los cuales podrían plantearse como biomarcadores de imagen de pacientes expuestos al desarrollo de esta complicación. Por último, al enfrentar a estos sujetos a una tarea de toma de decisiones y control inhibitorio, se aprecia una mayor activación de las áreas implicadas tanto en procesos de recompensa como de inhibición. Esto puede traducir la disfunción regional evidenciada previamente en el estudio metabólico desde la otra cara de la moneda, en la que se apreciaría un aumento de activación como reflejo de un posible mecanismo compensatorio para controlar las elecciones de riesgo. Además en estos pacientes se constata una respuesta de activación más precoz, que podría ser el reflejo de la predicción inicial de errores y la asignación de relevancia que precede a la toma de decisiones. Hay que destacar, que en esta tesis se enfatiza el estriado ventral como estructura clave que lleva a la disfunción de otras áreas pertenecientes al circuito mesocorticolímbico en paralelo a un aumento del desarrollo y gravedad del TCI en pacientes con EP. Además, se describe por primera vez la implicación del núcleo subtalámico derecho en una tarea de impulsividad cognitiva y la exclusividad de esta implicación en pacientes con EP y TCI, lo cual podría tener relevancia clínica en el marco terapeútico de la modulación conductual mediante estimulación cerebral profunda del núcleo subtalámico
Imaging Cognitive Impairment and Impulse Control Disorders in Parkinson's Disease
Dementia and mild forms of cognitive impairment as well as neuropsychiatric symptoms (i. e., impulse control disorders) are frequent and disabling non-motor symptoms of Parkinson's disease (PD). The identification of changes in neuroimaging studies for the early diagnosis and monitoring of the cognitive and neuropsychiatric symptoms associated with Parkinson's disease, as well as their pathophysiological understanding, are critical for the development of an optimal therapeutic approach. In the current literature review, we present an update on the latest structural and functional neuroimaging findings, including high magnetic field resonance and radionuclide imaging, assessing cognitive dysfunction and impulse control disorders in PD
Functional correlates of response inhibition in impulse control disorders in Parkinson’s disease
Available online 11 September 2021.Impulse control disorder is a prevalent side-effect of Parkinson’s disease (PD) medication, with a strong negative
impact on the quality of life of those affected. Although impulsivity has classically been associated with response
inhibition deficits, previous evidence from PD patients with impulse control disorder (ICD) has not revealed
behavioral dysfunction in response inhibition. In this study, 18 PD patients with ICD, 17 PD patients without this
complication, and 15 healthy controls performed a version of the conditional Stop Signal Task during functional
magnetic resonance imaging. Whole-brain contrasts, regions of interest, and functional connectivity analyses
were conducted. Our aim was to investigate the neural underpinnings of two aspects of response inhibition:
proactive inhibition, inhibition that has been prepared beforehand, and restrained inhibition, inhibition of an
invalid inhibitory tendency. We observed that, in respect to the other two groups, PD patients with ICD exhibited
hyperactivation of the stopping network bilaterally while performing proactive inhibition. When engaged in
restrained inhibition, they showed hyperactivation of the left inferior frontal gyrus, an area linked to action
monitoring. Restrained inhibition also resulted in changes to the functional co-activation between inhibitory
regions and left inferior parietal cortex and right supramarginal gyrus. Our findings indicate that PD patients
with ICD completed the inhibition task correctly, showing altered engagement of inhibitory and attentional
areas. During proactive inhibition they showed bilateral hyperactivation of two inhibitory regions, while during
restrained inhibition they showed additional involvement of attentional areas responsible for alerting and
orienting.This work was supported by grants from the Carlos III Institute of
Health (PI11/02109) and the ERA-Neuron program (PIM2010ERN-
0033). Additionally, the authors received the following grants and
honoraria: T.E.-P. received a grant from the Spanish Ministry of Economy
and Competitiveness (BES-2016-079489). P.M.P.-A. was supported
by grants from the Spanish Ministry of Economy and Competitiveness
(RYC-2014-15440), the Spanish Ministry of Science and Innovation
(PGC2018-093408-B-I00), and the Fundación Tatiana Pérez de Guzmán
el Bueno. I.N.-G. was the recipient of a Rio Hortega grant (CM16/00033)
from the Carlos III Institute of Health. I.N.-G. received honoraria from
Zambon and TEVA for travel and accommodation to attend scientific
meetings. M.C.R.-O. received financial support for her research from
national and local government institutions in Spain (Carlos III Institute
of Health, Basque Country Government, Diputacion Foral Guipuzcoa,
and CIBERNED). M.C.R.-O. received honoraria from Zambon, Bial, and
Boston Scientific for lectures, travel, and accommodation to attend scientific
meetings. BCBL acknowledges support from the Basque Government
through the BERC 2018-2021 program
Functional correlates of response inhibition in impulse control disorders in Parkinson’s disease
Available online 11 September 2021.Impulse control disorder is a prevalent side-effect of Parkinson’s disease (PD) medication, with a strong negative
impact on the quality of life of those affected. Although impulsivity has classically been associated with response
inhibition deficits, previous evidence from PD patients with impulse control disorder (ICD) has not revealed
behavioral dysfunction in response inhibition. In this study, 18 PD patients with ICD, 17 PD patients without this
complication, and 15 healthy controls performed a version of the conditional Stop Signal Task during functional
magnetic resonance imaging. Whole-brain contrasts, regions of interest, and functional connectivity analyses
were conducted. Our aim was to investigate the neural underpinnings of two aspects of response inhibition:
proactive inhibition, inhibition that has been prepared beforehand, and restrained inhibition, inhibition of an
invalid inhibitory tendency. We observed that, in respect to the other two groups, PD patients with ICD exhibited
hyperactivation of the stopping network bilaterally while performing proactive inhibition. When engaged in
restrained inhibition, they showed hyperactivation of the left inferior frontal gyrus, an area linked to action
monitoring. Restrained inhibition also resulted in changes to the functional co-activation between inhibitory
regions and left inferior parietal cortex and right supramarginal gyrus. Our findings indicate that PD patients
with ICD completed the inhibition task correctly, showing altered engagement of inhibitory and attentional
areas. During proactive inhibition they showed bilateral hyperactivation of two inhibitory regions, while during
restrained inhibition they showed additional involvement of attentional areas responsible for alerting and
orienting.This work was supported by grants from the Carlos III Institute of
Health (PI11/02109) and the ERA-Neuron program (PIM2010ERN-
0033). Additionally, the authors received the following grants and
honoraria: T.E.-P. received a grant from the Spanish Ministry of Economy
and Competitiveness (BES-2016-079489). P.M.P.-A. was supported
by grants from the Spanish Ministry of Economy and Competitiveness
(RYC-2014-15440), the Spanish Ministry of Science and Innovation
(PGC2018-093408-B-I00), and the Fundación Tatiana Pérez de Guzmán
el Bueno. I.N.-G. was the recipient of a Rio Hortega grant (CM16/00033)
from the Carlos III Institute of Health. I.N.-G. received honoraria from
Zambon and TEVA for travel and accommodation to attend scientific
meetings. M.C.R.-O. received financial support for her research from
national and local government institutions in Spain (Carlos III Institute
of Health, Basque Country Government, Diputacion Foral Guipuzcoa,
and CIBERNED). M.C.R.-O. received honoraria from Zambon, Bial, and
Boston Scientific for lectures, travel, and accommodation to attend scientific
meetings. BCBL acknowledges support from the Basque Government
through the BERC 2018-2021 program
Functional correlates of response inhibition in impulse control disorders in Parkinson’s disease
Impulse control disorder is a prevalent side-effect of Parkinson’s disease (PD) medication, with a strong negative
impact on the quality of life of those affected. Although impulsivity has classically been associated with response
inhibition deficits, previous evidence from PD patients with impulse control disorder (ICD) has not revealed
behavioral dysfunction in response inhibition. In this study, 18 PD patients with ICD, 17 PD patients without this
complication, and 15 healthy controls performed a version of the conditional Stop Signal Task during functional
magnetic resonance imaging. Whole-brain contrasts, regions of interest, and functional connectivity analyses
were conducted. Our aim was to investigate the neural underpinnings of two aspects of response inhibition:
proactive inhibition, inhibition that has been prepared beforehand, and restrained inhibition, inhibition of an
invalid inhibitory tendency. We observed that, in respect to the other two groups, PD patients with ICD exhibited
hyperactivation of the stopping network bilaterally while performing proactive inhibition. When engaged in
restrained inhibition, they showed hyperactivation of the left inferior frontal gyrus, an area linked to action
monitoring. Restrained inhibition also resulted in changes to the functional co-activation between inhibitory
regions and left inferior parietal cortex and right supramarginal gyrus. Our findings indicate that PD patients
with ICD completed the inhibition task correctly, showing altered engagement of inhibitory and attentional
areas. During proactive inhibition they showed bilateral hyperactivation of two inhibitory regions, while during
restrained inhibition they showed additional involvement of attentional areas responsible for alerting and
orientin
Different susceptibility to pramipexole-induced impulsivity in a rat model of parkinson’s disease
Impulse Control Disorders (ICD) in patients with Parkinson’s disease are abnormal behaviors caused by long-term use of dopamine agonists, which pathophysiology is poorly understood. Using parkinsonian rats (adeno-associated viral
vectors-mediated overexpression of A53T human α-synuclein in the substantia nigra compacta), we evaluated the impulsive behaviour under acute (0.25 and 3 mg/kg) and chronic (0.25 mg/kg for 4 weeks) administration of pramipexole (PPX) with the Variable Delay-to-Signal (VDS) task (motor and choice impulsivities). Changes in striatal D1 and D2 receptors expression were also analysed. Before treatment, the striatal dopaminergic depletion caused a significant increase of both impulsivity domains with respect
to basal condition. In lesioned rats, acutely given PPX 0.25 mg/kg dose increased choice impulsivity only with regard to basal values. Meanwhile, 3 mg/kg PPX increased choice impulsivity compared to their own values at different conditions: basal, before treatment and after acute 0.25 mg/kg PPX administration. After chronic administration, two populations of lesioned animals were distinguished, one showing the same behaviour as control animals and other displaying an increased motor/response (first week of treatment) and cognitive/choice impulsivities (third week of treatment) compared to control animals. This impulsive behaviour disappeared when animals were tested in OFF state. Lower D2 expression in both Caudate-Putamen and Nucleus Accubens and lower D1 levels in Nucleus Accumbens in lesioned rats than in control animals were observed. Therefore, our results indicate that the pro-impulsive effect of PPX in this animal model of PD depends on the dose and administration paradigm employed and the individual predisposition, and it is associated to striatal dopamine receptors expression changes, especially in Nucleus Accumbens. Thus, this model could constitute a valid tool to investigate the pathophysiology of ICD.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.
DFG11/019, PI11/0210
Using Kinect to classify Parkinson's disease stages related to severity of gait impairment
Background: Parkinson’s Disease (PD) is a chronic neurodegenerative disease associated with motor problems such
as gait impairment. Different systems based on 3D cameras, accelerometers or gyroscopes have been used in related
works in order to study gait disturbances in PD. Kinect has also been used to build these kinds of systems, but
contradictory results have been reported: some works conclude that Kinect does not provide an accurate method of
measuring gait kinematics variables, but others, on the contrary, report good accuracy results.
Methods: In this work, we have built a Kinect-based system that can distinguish between different PD stages, and
have performed a clinical study with 30 patients suffering from PD belonging to three groups: early PD patients
without axial impairment, more evolved PD patients with higher gait impairment but without Freezing of Gait (FoG),
and patients with advanced PD and FoG. Those patients were recorded by two Kinect devices when they were
walking in a hospital corridor. The datasets obtained from the Kinect were preprocessed, 115 features identified, some
methods were applied to select the relevant features (correlation based feature selection, information gain, and
consistency subset evaluation), and different classification methods (decision trees, Bayesian networks, neural
networks and K-nearest neighbours classifiers) were evaluated with the goal of finding the most accurate method for
PD stage classification.
Results: The classifier that provided the best results is a particular case of a Bayesian Network classifier (similar to a
Naïve Bayesian classifier) built from a set of 7 relevant features selected by the correlation-based on feature selection
method. The accuracy obtained for that classifier using 10-fold cross validation is 93.40%. The relevant features are
related to left shin angles, left humerus angles, frontal and lateral bents, left forearm angles and the number of steps
during spin.
Conclusions: In this paper, it is shown that using Kinect is adequate to build a inexpensive and comfortable system
that classifies PD into three different stages related to FoG. Compared to the results of previous works, the obtained
accuracy (93.40%) can be considered high. The relevant features for the classifier are: a) movement and position of the
left arm, b) trunk position for slightly displaced walking sequences, and c) left shin angle, for straight walking
sequences. However, we have obtained a better accuracy (96.23%) for a classifier that only uses features extracted
from slightly displaced walking steps and spin walking steps. Finally, the obtained set of relevant features may lead to
new rehabilitation therapies for PD patients with gait problems
Multicentre, randomised, single-blind, parallel group trial to compare the effectiveness of a Holter for Parkinson's symptoms against other clinical monitoring methods: study protocol
Introduction
In recent years, multiple studies have aimed to develop and validate portable technological devices capable of monitoring the motor complications of Parkinson's disease patients (Parkinson's Holter). The effectiveness of these monitoring devices for improving clinical control is not known.
Methods and analysis
This is a single-blind, cluster-randomised controlled clinical trial. Neurologists from Spanish health centres will be randomly assigned to one of three study arms (1:1:1): (a) therapeutic adjustment using information from a Parkinson?s Holter that will be worn by their patients for 7 days, (b) therapeutic adjustment using information from a diary of motor fluctuations that will be completed by their patients for 7 days and (c) therapeutic adjustment using clinical information collected during consultation. It is expected that 162 consecutive patients will be included over a period of 6 months.
The primary outcome is the efficiency of the Parkinson?s Holter compared with traditional clinical practice in terms of Off time reduction with respect to the baseline (recorded through a diary of motor fluctuations, which will be completed by all patients). As secondary outcomes, changes in variables related to other motor complications (dyskinesia and freezing of gait), quality of life, autonomy in activities of daily living, adherence to the monitoring system and number of doctor?patient contacts will be analysed. The noninferiority of the Parkinson's Holter against the diary of motor fluctuations in terms of Off time reduction will be studied as the exploratory objective.
Ethics and dissemination approval for this study has been obtained from the Hospital Universitari de Bellvitge Ethics Committee. The results of this study will inform the practical utility of the objective information provided by a Parkinson's Holter and, therefore, the convenience of adopting this technology in clinical practice and in future clinical trials. We expect public dissemination of the results in 2022.Funding This work is supported by AbbVie S.L.U, the Instituto de Salud Carlos III [DTS17/00195] and the European Fund for Regional Development, 'A way to make Europe'
Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study
Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe