Is arginine test a reliable tool for differential diagnosis of multiple system atrophy?

Arginine test for differential diagnosis of multiple system atrophy

Growth hormone stimulation tests in the differential diagnosis of Parkinson'sdisease

Idiopathic Parkinson's disease (IPD) is a common neurodegenerative disorder whose differential diagnosis from other forms of atypical parkinsonism, for instance multiple system atrophy (MSA) or progressive supranuclear palsy, may be difficult, especially in the early stages. Growth hormone stimulation tests have been recently reported to be useful in the differential diagnosis between IPD and MSA. Both clonidine, an alpha(2)-adrenoceptor agonist, and arginine, an amino acid activating the cholinergic system, have been used to assess growth hormone response in patients with IPD and MSA. This review summarizes the results of several studies and discusses the validity of these tests in the differential diagnosis of parkinsonisms

Identification of a Gait Pattern for Detecting Mild Cognitive Impairment in Parkinson's Disease

: The aim of this study was to determine a gait pattern, i.e., a subset of spatial and temporal parameters, through a supervised machine learning (ML) approach, which could be used to reliably distinguish Parkinson's Disease (PD) patients with and without mild cognitive impairment (MCI). Thus, 80 PD patients underwent gait analysis and spatial-temporal parameters were acquired in three different conditions (normal gait, motor dual task and cognitive dual task). Statistical analysis was performed to investigate the data and, then, five ML algorithms and the wrapper method were implemented: Decision Tree (DT), Random Forest (RF), Naïve Bayes (NB), Support Vector Machine (SVM) and K-Nearest Neighbour (KNN). First, the algorithms for classifying PD patients with MCI were trained and validated on an internal dataset (sixty patients) and, then, the performance was tested by using an external dataset (twenty patients). Specificity, sensitivity, precision, accuracy and area under the receiver operating characteristic curve were calculated. SVM and RF showed the best performance and detected MCI with an accuracy of over 80.0%. The key features emerging from this study are stance phase, mean velocity, step length and cycle length; moreover, the major number of features selected by the wrapper belonged to the cognitive dual task, thus, supporting the close relationship between gait dysfunction and MCI in PD

Development of the Digital Inclusion Questionnaire (DIQUEST) in Parkinson's Disease

Background No tool is currently able to measure digital inclusion in clinical populations suitable for telemedicine. We developed the "Digital Inclusion Questionnaire" (DIQUEST) to estimate access and skills in Parkinson's Disease (PD) patients and verified its properties with a pilot study.Methods Thirty PD patients completed the initial version of the DIQUEST along with the Mobile Device Proficiency Questionnaire (MDPQ) and a practical computer task. A Principal Components Analysis (PCA) was conducted to define the DIQUEST factor structure and remove less informative items. We used Cronbach's alpha to measure internal reliability and Spearman's correlation test to determine the convergent and predictive validity with the MDPQ and the practical task, respectively.Results The final version of the DIQUEST consisted of 20 items clustering in five components: "advanced skills," "navigation skills," "basic skills/knowledge," "physical access," and "economical access." All components showed high reliability (alpha > 0.75) as did the entire questionnaire (alpha = 0.94). Correlation analysis demonstrated high convergent (rho: 0.911; p<0.001) and predictive (rho: 0.807; p<0.001) validity.Conclusions We have here presented the development of the DIQUEST as a screening tool to assess the level of digital inclusion, particularly addressing the access and skills domains. Future studies are needed for its validation beyond PD

The Correlation between Retinal and Choroidal Thickness with Age-Related White Matter Hyperintensities in Progressive Supranuclear Palsy

Choroid; Optical coherence tomography; RetinaCoroide; Tomografia de coherència òptica; RetinaCoroides; Tomografía de coherencia óptica; RetinaProgressive supranuclear palsy (PSP) is a rare neurodegenerative disease. Recently, several retinal layers in PSP compared to healthy controls. were found to be thinner. However, no studies evaluating the correlation between retinal layers and cerebral white matter changes, nor eventual choroidal changes in PSP, have been conducted so far. The goals of the present study were to explore potential differences in choroidal structure between PSP and healthy controls, and to describe the relationship between retinal layers’ thickness and volume, using spectral-domain optical coherence tomography (SD-OCT) and age-related white matter change scores (ARWMC) using magnetic resonance imaging (MRI) of the brain. Choroidal structures of 26 PSP patients and 26 healthy controls using standard SD-OCT with an enhanced depth imaging (EDI) approach were analyzed; then, retinal the structures of 16 of these PSP patients using standard SD-OCT were examined; finally, the same patients underwent brain MRI, and their cerebral white matter changes were calculated. Non-statistically significant differences between PSP patients’ and healthy controls’ choroidal structure were found. On the contrary, PSP patients’ inner retinal layers (INR), retinal pigmented epithelium (RPE) and all retinal layers’ thicknesses in the macular region were found to be significantly correlated with ARWMC, independently from age and axial length (AL). PSP patients’ neurological alterations go hand in hand with retinal ones, independently from age and axial length. Our results suggest a mutual relationship between cerebral and retinal structure pathological alterations. On the other hand, no significant differences in the choroidal evaluation compared to healthy controls have been found