Unit:
Τομέας Κοινωνικής Ιατρικής - Ψυχιατρικής και ΝευρολογίαςLibrary of the School of Health Sciences
Author:
Artemiadis Artemios
Dissertation committee:
Μαρία Αναγνωστούλη, Επίκουρη Καθηγήτρια, Νευρολογική Κλινική, Αιγινήτειο Νοσοκομείο
Μιχαήλ Ρέντζος , Αναπληρωτής Καθηγητής, Νευρολογική Κλινική, Αιγινήτειο Νοσοκομείο
Ιωάννης Ζαλώνης, Επίκουρος Καθηγητής, Νευρολογική Κλινική, Αιγινήτειο Νοσοκομείο
Μαρία-Ελευθερία Ευαγγελοπούλου, Επίκουρη Καθηγήτρια, Νευρολογική Κλινική, Αιγινήτειο Νοσοκομείο
Γιώργος Χρούσος, Καθηγητής, Α' Παιδιατρική Κλινική, ΕΚΠΑ
Γιώργος Παρασκευάς, Επίκουρος Καθηγητής, Νευρολογική Κλινική, Αιγινήτειο Νοσοκομείο
Κωνσταντίνος Ψάρρος, Επίκουρος Καθηγητής, Ψυχιατρική Κλινική, Αιγινήτειο Νοσοκομείο
Original Title:
Νευροφυσιολογική και νευροψυχολογική διερεύνηση των διαταραχών των γνωστικών λειτουργιών σε ασθενείς με σκλήρυνση κατά πλάκας
Translated title:
Neurophysiological and neuropsychological evaluation of cognitive impairment in multiple sclerosis patients
Summary:
Background
Multiple sclerosis (MS) is an acquired demyelinating disease of the central nervous system of unknown origin, affecting mainly young adults and causing various neurological symptoms, including cognitive impairment (CI). The prevalence of CI among patients is 26-60%, it occurs early in the disease course and affects the quality of life of patients. CI in MS affects cognitive processing speed, visuospatial and verbal memory, cardinally assessed by neuropsychological testing (NPT). In the recently published literature, interesting associations between new MRI (Magnetic Resonance Imaging) techniques and indices have been documented. In parallel, there have been attempts to link CI with the P300 event-related potential, which reflects brain cognitive function during the oddball paradigm task. To our knowledge, there have been no studies examining the relationship between the electrophysiological and the new automated and non-automated MRI markers of CI in MS.
Aim
The primary aim of this study was to investigate the relationship between specific MRI markers and the P300 event-related potential in MS. Secondary aims include the examination of the diagnostic accuracy of the NPT and neurophysiological testing and the role of neurophysiology and neuroimaging in CI in MS.
Materials and Methods
This is a cross-sectional study of 61 patients with relapsing-remitting MS and 51 age and gender matched healthy controls A sample of 156 healthy controls was also used to ascertain CI based on the NPT. Measurements included sodiodemographic factors, disease-related characteristics, NPT (Brief International Cognitive Assessment for Multiple Sclerosis-BICAMS), fatigue (using visual analogue scales), psychological state (Depression Anxiety Stress Scale 21-DASS-21), electrophysiological markers of the P300 event-related potential and fully automated (3D, MIPAV, SIENAX and FIRST methods) and non-automated (2D, e.g. third ventricle width, corpus callosum index etc.) MRI assessments.
Results
44.3% and 67.2% of MS patients were found with CI based on NPT and neurophysiological testing, respectively. The agreement rate of these two testing methods reached 56.9%. Electrophysiological testing had slightly more diagnostic accuracy compared to NPT (76.1% vs. 71.4%) for separating MS and healthy status. P300 amplitude and latency were significantly positively and negatively correlated with cognitive function, respectively. P300 latency was better at discriminating MS patients vs. healthy controls, irrespective of their cognitive function, while P300 amplitude was better at detecting CI among MS patients. Visuospatial memory separated patients with and without electrophysiologically defined CI, while cognitive speed processing distinguished MS patients from healthy controls. Reduced P300 amplitude was associated with decreased both grey matter and peripheral grey matter volume. Frontal horn and third ventricle width were found to be significant determinants of the P300 amplitude. P300 latency was not associated with any MRI marker. Statistically significant differences between patients with and without CI were also found for third ventricle width and volume, corpus callosum index and lesion volume. The main determinants of the total cognitive score were the corpus callosum index and lesion volume. The main determinants of the cognitive speed processing was the corpus callosum index, for verbal memory the frontal horn width and lesion volume and for visuospatial memory the third ventricle width.
Conclusions
This study showed that electrophysiological testing is as effective as NPT for assessing cognitive function in MS. In addition, the combined MRI and electrophysiological testing permits a more comprehensive assessment of cognitive function in MS. In the future, these assessments are expected to play a crucial role both in the clinical research and in the clinical surveillance of MS patients by neurologists.
Main subject category:
Health Sciences
Keywords:
multiple sclerosis; cognitive function; neurophysiological test; evoked potentials; P300; neuropsychological tests; magnetic resonance imaging; volumetric
Number of references:
230
