Thomas Desmidt
François Rabelais University
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Publication
Featured researches published by Thomas Desmidt.
International Journal of Geriatric Psychiatry | 2015
Julien Delrieu; Thomas Desmidt; Vincent Camus; Sandrine Sourdet; Claire Boutoleau-Bretonnière; Emmanuel Mullin; Bruno Vellas; Pierre Payoux; Thibaud Lebouvier; Alzheimer's Disease Neuroimaging Initiative
The goal of this study is to evaluate brain metabolism in mild cognitive impairment (MCI) patients with and without apathy (as determined by the Neuropsychiatric Inventory Questionnaire).
Psychiatry Research-neuroimaging | 2011
Thomas Desmidt; Melouka Elkateb Hachemi; Jean-Pierre Remenieras; Pierre Lecomte; Nicole Ferreira-Maldent; F. Patat; Vincent Camus
We used Tissue Pulsatility Imaging (TPI) to compare the Brain Tissue Pulsatility (BTP) in depressed (n=11) and non-depressed (n=13) type-2 diabetic non-demented patients aged 50 years and older. Both maximum and mean BTP were significantly decreased in depressed diabetic subjects compared to non-depressed diabetic subjects.
Psychiatry Research-neuroimaging | 2014
Marine Naudin; Karl Mondon; Wissam El-Hage; Thomas Desmidt; Nematollah Jaafari; Catherine Belzung; Philippe Gaillard; Caroline Hommet; Boriana Atanasova
Major depression and Alzheimer׳s disease (AD) are often observed in the elderly. The identification of specific markers for these diseases could improve their screening. The aim of this study was to investigate long-term odor recognition memory in depressed and AD patients, with a view to identifying olfactory markers of these diseases. We included 20 patients with unipolar major depressive episodes (MDE), 20 patients with mild to moderate AD and 24 healthy subjects. We investigated the cognitive profile and olfactory memory capacities (ability to recognize familiar and unfamiliar odors) of these subjects. Olfactory memory test results showed that AD and depressed patients were characterized by significantly less correct responses and more wrong responses than healthy controls. Detection index did not differ significantly between patients with major depression and those with AD when the results were analyzed for all odors. However, MDE patients displayed an impairment of olfactory memory for both familiar and unfamiliar odors, whereas AD subjects were impaired only in the recognition of unfamiliar odors, with respect to healthy subjects. If preservation of olfactory memory for familiar stimuli in patients with mild to moderate AD is confirmed, this test could be used in clinical practice as a complementary tool for diagnosis.
Journal of Cerebral Blood Flow and Metabolism | 2014
Redouane Ternifi; Xavier Cazals; Thomas Desmidt; Frédéric Andersson; Vincent Camus; Jean-Philippe Cottier; F. Patat; Jean-Pierre Remenieras
White-matter hyperintensity (WMH) is frequently seen in magnetic resonance imaging (MRI), but the complete physiopathology of WMH remains to be elucidated. In this study, we sought to determine whether there is an association between the maximum brain tissue displacement (maxBTD), as assessed by ultrasound, and the WMH, as observed by MRI. Nine healthy women aged 60 to 85 years underwent ultrasound and MRI assessments. We found a significant negative correlation between maxBTD and WMH (ρ = -0.86, P<0.001), suggesting a link between cerebral hypoperfusion and WMH.
Psychiatry Research-neuroimaging | 2017
Carmen Andreescu; Dana L. Tudorascu; Lei K. Sheu; Anusha Rangarajan; Meryl A. Butters; Sarah Walker; Rachel Berta; Thomas Desmidt; Howard J. Aizenstein
Late-life Generalized Anxiety Disorder (GAD) is relatively understudied and the underlying structural and functional neuroanatomy has received little attention. In this study, we compare the brain structural characteristics in white and gray matter in 31 non-anxious older adults and 28 late-life GAD participants. Gray matter indices (cortical thickness and volume) were measured using FreeSurfer parcellation and segmentation, and mean diffusivity was obtained through Diffusion Tensor Imaging (DTI). We assessed both macroscopic white matter changes [using white matter hyperintensity (WMH) burden] and microscopic white matter integrity [using fractional anisotropy (FA)]. No differences in macro- or microscopic white matter integrity were found between GAD and non-anxious controls (HC). GAD participants had lower cortical thickness in the orbitofrontal cortex (OFC), inferior frontal gyrus, and pregenual anterior cingulate cortex (ACC). Higher worry severity was associated with gray matter changes in OFC, ACC and the putamen. The results did not survive the multiple comparison correction, but the effect sizes indicate a moderate effect. The study suggests that late-life GAD is associated with gray matter changes in areas involved in emotion regulation, more so than with white matter changes. We conclude that anxiety-related chronic hypercortisolemia may have a dissociative effect on gray and white matter integrity.
Neuropsychopharmacology | 2017
Thomas Desmidt; Bruno Brizard; Paul-Armand Dujardin; Redouane Ternifi; Jean-Pierre Remenieras; F. Patat; Frédéric Andersson; Jean-Philippe Cottier; Emilie Vierron; Valérie Gissot; Kang Kim; Howard J. Aizenstein; Wissam El-Hage; Vincent Camus
Cerebrovascular disease (CVD) is consistently associated with late-life depression but poorly documented in midlife depression. It can be hypothesized that the relatively low sensitivity of conventional neuroimaging techniques does not allow the detection of subtle CVD in midlife depression. We used tissue pulsatility imaging (TPI), a novel ultrasound (US) neuroimaging technique that has demonstrated good sensitivity to detect changes in the pulsatility of small brain volumes, to identify early and subtle changes in brain vascular function in midlife depression. We compared the maximum and mean brain tissue pulsatility (MaxBTP and MeanBTP), as identified by TPI, between three groups of middle-aged females matched for age: patients with depression (n=25), patients with remitted depression (n=24) and community controls (n=25). MRI arterial spin labeling, white matter hyperintensities (WMHs) and transcranial doppler (TCD) were used as control conventional markers for CVD. We found no difference in the MRI and TCD measures among the three groups. In contrast, depressive patients showed an increased BTP related to the mean global brain pulsatility (MeanBTP) and no change related to large vessels (MaxBTP) in comparison with the remitted and control groups. US neuroimaging is a highly accurate method to detect brain pulsatility changes related to cerebrovascular functioning, and TPI identified an increased BTP in midlife depressed patients, suggesting early and subtle vascular impairments in this population at risk for CVD such as stroke or WMHs. Because high pulsatility could represent prodromal cerebrovascular changes that damage the brain over time, this paper provides a potential target for blocking the progression of CVD.
Journal of Stroke & Cerebrovascular Diseases | 2017
Julie Biogeau; Thomas Desmidt; Paul-Armand Dujardin; Redouane Ternifi; Charlotte Eudo; Emilie Vierron; Jean-Pierre Remenieras; F. Patat; Vincent Camus; Thierry Constans
BACKGROUND Orthostatic hypotension (OH) is highly prevalent in the elderly, and this population can be exposed to serious complications, including falls and cognitive disorders, as well as overall mortality. However, the pathophysiology of OH is still poorly understood, and innovative methods of cerebral blood flow (CBF) assessment have been required to accurately investigate cerebrovascular reactivity in OH. OBJECTIVES We want to compare brain tissue pulsatility (BTP) changes during an orthostatic challenge in elderly patients over 80 with and without OH. MATERIALS AND METHODS Forty-two subjects aged 80 and over were recruited from the geriatric unit of the Hospital of Tours, France, and were divided into two groups according to the result of an orthostatic challenge. The noninclusion criteria were any general unstable medical condition incompatible with orthostatic challenge, having no temporal acoustic window, severe cognitive impairment (Mini Mental Status Examination <15), history of stroke, and legal guardianship. We used the novel and highly sensitive ultrasound technique of tissue pulsatility imaging to measure BTP changes in elderly patients with (n = 22) and without OH (n = 17) during an orthostatic challenge. RESULTS We found that the mean brain tissue pulsatility related to global intracranial pulsatility, but not maximum brain tissue pulsatility related to large arteries pulsatility, decreased significantly in OH patients, with a delay compared with the immediate drop in peripheral blood pressure. CONCLUSION Global pulsatile CBF changes and small vessels pulsatility, rather than changes in only large arteries, may be key mechanisms in OH to account for the links between OH and cerebrovascular disorders.
Psychiatry Research-neuroimaging | 2015
Marine Naudin; Karl Mondon; Wissam El-Hage; Elise Perriot; Mohamed Boudjarane; Thomas Desmidt; Adrien Lorette; Catherine Belzung; Caroline Hommet; Boriana Atanasova
Major Depression and Alzheimer׳s disease (AD) are two diseases in the elderly characterized by an overlap of early symptoms including memory and emotional disorders. The identification of specific markers would facilitate their diagnosis. The aim of this study was to identify such markers by investigating gustatory function in depressed and AD patients. We included 20 patients with unipolar major depressive episodes (MDE), 20 patients with mild to moderate AD and 24 healthy individuals. We investigated the cognitive profile (depression, global cognitive efficiency and social/physical anhedonia) and gustatory function (ability to identify four basic tastes and to judge their intensity and hedonic value) in all participants. We found that AD patients performed worse than healthy participants in the taste identification test (for the analysis of all tastants together); however, this was not the case for depressed patients. We found no significant differences among the three groups in their ability to evaluate the intensity and hedonic value of the four tastes. Overall, our findings suggest that a taste identification test may be useful to distinguish AD and healthy controls but further investigation is required to conclude whether such a test can differentiate AD and depressed patients.
Journal of the American Geriatrics Society | 2009
Thomas Desmidt; Thierry Constans
ACKNOWLEDGMENTS These authors would thank Drs. Yu-Fang Ma and GuiSheng Wu for their help in preparing the paper. Conflict of Interest: The editor in chief has reviewed the conflict of interest checklist provided by the authors and has determined that the authors have no financial or any other kind of personal conflicts with this paper. The study was supported by the National Basic Research Program of China (No. 2007CB507405). Author Contribution: J-J Ye and Y-Y Gong: had equal contribution to this study, collected the information, conceived the study, and wrote the manuscript. L Xie, J-C Li, L Peng, S-G Lian, Z Yang, and Y-F Zhou collected the information. Sponsor’s Role: The funding source had no role in the design, methods, subject recruitment, data collect, analysis, or preparation of the manuscript.
Neuroscience & Biobehavioral Reviews | 2017
Francois Kazour; Sami Richa; Thomas Desmidt; Mathieu Lemaire; Boriana Atanasova; Wissam El Hage
HIGHLIGHTSPatients with bipolar disorder present with several olfactory and gustatory dysfunctions.Dysfunction in olfactory identification may be potential marker for bipolar disorder.Olfactory acuity is associated with psychosocial and cognitive performances in bipolar disorder.Bipolar patients have more gustatory dysfunction than non‐bipolar depressed patients and controls. ABSTRACT Olfactory and gustatory dysfunctions have been described in different psychiatric disorders. Several studies have found gustatory and olfactory function change in bipolar disorders with various results. The aim of this study is to have a systematic review of studies evaluating gustatory and olfactory function in bipolar disorders. After a systematic search, 15 studies on olfaction and 5 studies on taste were included in this review. The UPSIT (University of Pennsylvania Smell Identification Test) and Sniffin’ Sticks were the most widely used tests to evaluate smell. Some studies on olfaction described dysfunctions in smell identification as potential markers for bipolar disorders. Moreover, olfactory acuity was associated with psychosocial and cognitive performances. For taste, only few studies used standardized tests to evaluate gustation. These studies showed that patients with Bipolar disorders had more gustatory dysfunction compared to controls, and to non‐bipolar depressed patients.