Clarissa Ferrari

The EADC-ADNI Harmonized Protocol for manual hippocampal segmentation on magnetic resonance: Evidence of validity

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.

Prevalence and Risk Factors of Violence by Psychiatric Acute Inpatients: A Systematic Review and Meta-Analysis.

Background Violence in acute psychiatric wards affects the safety of other patients and the effectiveness of treatment. However, there is a wide variation in reported rates of violence in acute psychiatric wards. Objectives To use meta-analysis to estimate the pooled rate of violence in published studies, and examine the characteristics of the participants, and aspects of the studies themselves that might explain the variation in the reported rates of violence (moderators). Method Systematic meta-analysis of studies published between January 1995 and December 2014, which reported rates of violence in acute psychiatric wards of general or psychiatric hospitals in high-income countries. Results Of the 23,972 inpatients described in 35 studies, the pooled proportion of patients who committed at least one act of violence was 17% (95% confidence interval (CI) 14–20%). Studies with higher proportions of male patients, involuntary patients, patients with schizophrenia and patients with alcohol use disorder reported higher rates of inpatient violence. Conclusion The findings of this study suggest that almost 1 in 5 patients admitted to acute psychiatric units may commit an act of violence. Factors associated with levels of violence in psychiatric units are similar to factors that are associated with violence among individual patients (male gender, diagnosis of schizophrenia, substance use and lifetime history of violence).

What do you feel if I apply transcranial electric stimulation? Safety, sensations and secondary induced effects

OBJECTIVE The goals of this work are to report data regarding a large number of stimulation sessions and to use model analyses to explain the similarities or differences in the sensations induced by different parameters of tES application. METHODS We analysed sensation data relative to 693 different tES sessions. In particular, we studied the effects on sensations induced by different types of current, categories of polarity and frequency, different timing, levels of current density and intensity, different electrode sizes and different electrode locations (areas). RESULTS The application of random or fixed alternating current stimulation (i.e., tRNS and tACS) over the scalp induced less sensation compared with transcranial direct current stimulation (tDCS), regardless of the application parameters. Moreover, anodal tDCS induced more annoyance in comparison to other tES. Additionally, larger electrodes induced stronger sensations compared with smaller electrodes, and higher intensities were more strongly perceived. Timing of stimulation, montage and current density did not influence sensations perception. The analyses demonstrated that the induced sensations could be clustered on the basis of the type of somatosensory system activated. Finally and most important no adverse events were reported. CONCLUSION Induced sensations are modulated by electrode size and intensity and mainly pertain to the cutaneous receptor activity of the somatosensory system. Moreover, the procedure currently used to perform placebo stimulation may not be totally effective when compared with anodal tDCS. SIGNIFICANCE The reported observations enrich the literature regarding the safety aspects of tES, confirming that it is a painless and safe technique.

Mild cognitive impairment with suspected nonamyloid pathology (SNAP) Prediction of progression

Objectives: The aim of this study was to investigate predictors of progressive cognitive deterioration in patients with suspected non–Alzheimer disease pathology (SNAP) and mild cognitive impairment (MCI). Methods: We measured markers of amyloid pathology (CSF β-amyloid 42) and neurodegeneration (hippocampal volume on MRI and cortical metabolism on [18F]-fluorodeoxyglucose–PET) in 201 patients with MCI clinically followed for up to 6 years to detect progressive cognitive deterioration. We categorized patients with MCI as A+/A− and N+/N− based on presence/absence of amyloid pathology and neurodegeneration. SNAPs were A−N+ cases. Results: The proportion of progressors was 11% (8/41), 34% (14/41), 56% (19/34), and 71% (60/85) in A−N−, A+N−, SNAP, and A+N+, respectively; the proportion of APOE ε4 carriers was 29%, 70%, 31%, and 71%, respectively, with the SNAP group featuring a significantly different proportion than both A+N− and A+N+ groups (p ≤ 0.005). Hypometabolism in SNAP patients was comparable to A+N+ patients (p = 0.154), while hippocampal atrophy was more severe in SNAP patients (p = 0.002). Compared with A−N−, SNAP and A+N+ patients had significant risk of progressive cognitive deterioration (hazard ratio = 2.7 and 3.8, p = 0.016 and p < 0.001), while A+N− patients did not (hazard ratio = 1.13, p = 0.771). In A+N− and A+N+ groups, none of the biomarkers predicted time to progression. In the SNAP group, lower time to progression was correlated with greater hypometabolism (r = 0.42, p = 0.073). Conclusions: Our findings support the notion that patients with SNAP MCI feature a specific risk progression profile.

Enhancing verbal episodic memory in older and young subjects after non-invasive brain stimulation

Memory is the capacity to store, maintain, and retrieve events or information from the mind. Difficulties in verbal episodic memory commonly occur in healthy aging. In this paper, we assess the hypothesis that anodal transcranial direct current stimulation (tDCS) applied over the dorsolateral prefrontal cortex (DLPFC) or over the parietal cortex (PARC) could facilitate verbal episodic memory in a group of 32 healthy older adults and in a group of 32 young subjects relative to a sham stimulation using a single-blind randomized controlled design. Each participant underwent two sessions of anodal tDCS (left and right) and one session of sham stimulation. Overall, our results demonstrated that, in young and in older subjects, anodal tDCS applied during the retrieval phase facilitates verbal episodic memory. In particular, we found that tDCS applied over the left and right regions (DLPFC and PARC) induced better performance in young participants; only tDCS applied over the left regions (DLPFC and PARC) increased retrieval in older subjects. These results suggest that anodal tDCS can be a relevant tool to modulate the long-term episodic memory capacities of young and older subjects.

Anodal tDCS during face-name associations memory training in Alzheimer's patients

Objective: Given the limited effectiveness of pharmacological treatments, non-pharmacological interventions to treat Alzheimers disease (AD) have gained attention in recent years. The aim of the present study is to investigate the effects of anodal tDCS (AtDCS) combined with memory training on face-name associations in an AD patient sample. Methods: Thirty six AD patients were randomly assigned to one of three study groups: Group 1, AtDCS plus individualized computerized memory training; Group 2, placebo tDCS plus individualized computerized memory training; Group 3, AtDCS plus motor training. Results: A general improvement in performance was observed after 2 weeks of memory training. Both the anodal tDCS plus individualized computerized memory training and the placebo tDCS plus individualized computerized memory training groups had significantly improved performances at 2 weeks compared with the AtDCS plus motor training group. Conclusion: Our findings suggest a beneficial effect of individualized memory rehabilitation in AD patients.

Mild cognitive impairment in Parkinson's disease is improved by transcranial direct current stimulation combined with physical therapy

Parkinsons disease (PD) is characterized by both motor and cognitive deficits. In PD, physical exercise has been found to improve physical functioning. Recent studies demonstrated that repeated sessions of transcranial direct current stimulation led to an increased performance in cognitive and motor tasks in patients with PD.

Harmonized benchmark labels of the hippocampus on magnetic resonance: The EADC-ADNI project

A globally harmonized protocol (HarP) for manual hippocampal segmentation based on magnetic resonance has been recently developed by a task force from European Alzheimers Disease Consortium (EADC) and Alzheimers Disease Neuroimaging Initiative (ADNI). Our aim was to produce benchmark labels based on the HarP for manual segmentation.

Assessment of the incremental diagnostic value of florbetapir F 18 imaging in patients with cognitive impairment: The incremental diagnostic value of amyloid PET with [18F]-florbetapir (INDIA-FBP) study

Importance Cerebral amyloidosis is a key abnormality in Alzheimer disease (AD) and can be detected in vivo with positron emission tomography (PET) ligands. Although amyloid PET has clearly demonstrated analytical validity, its clinical utility is debated. Objective To evaluate the incremental diagnostic value of amyloid PET with florbetapir F 18 in addition to the routine clinical diagnostic assessment of patients evaluated for cognitive impairment. Design, Setting, and Participants The Incremental Diagnostic Value of Amyloid PET With [18F]-Florbetapir (INDIA-FBP) Study is a multicenter study involving 18 AD evaluation units from eastern Lombardy, Northern Italy, 228 consecutive adults with cognitive impairment were evaluated for AD and other causes of cognitive decline, with a prescan diagnostic confidence of AD between 15% and 85%. Participants underwent routine clinical and instrumental diagnostic assessment. A prescan diagnosis was made, diagnostic confidence was estimated, and drug treatment was provided. At the time of this workup, an amyloid PET/computed tomographic scan was performed, and the result was communicated to physicians after workup completion. Physicians were asked to review the diagnosis, diagnostic confidence, and treatment after the scan. The study was conducted from August 5, 2013, to December 31, 2014. Main Outcomes and Measures Primary outcomes were prescan to postscan changes of diagnosis, diagnostic confidence, and treatment. Results Of the 228 participants, 107 (46%) were male; mean (SD) age was 70.5 (7) years. Diagnostic change occurred in 46 patients (79%) having both a previous diagnosis of AD and an amyloid-negative scan (P < .001) and in 16 (53%) of those with non-AD diagnoses and an amyloid-positive scan (P < .001). Diagnostic confidence in AD diagnosis increased by 15.2% in amyloid-positive (P < .001; effect size Cohen d = 1.04) and decreased by 29.9% in amyloid-negative (P < .001; d = -1.19) scans. Acetylcholinesterase inhibitors and memantine hydrochloride were introduced in 61 (65.6%) patients with positive scan results who had not previously received those drugs, and the use of the drugs was discontinued in 6 (33.3%) patients with negative scan results who were receiving those drugs (P < .001). Conclusions and Relevance Amyloid PET in addition to routine assessment in patients with cognitive impairment has a significant effect on diagnosis, diagnostic confidence, and drug treatment. The effect on health outcomes, such as morbidity and mortality, remains to be assessed.

Time up and go task performance improves after transcranial direct current stimulation in patient affected by Parkinson's disease.

Locomotor disturbances represent one of the major distress in everyday life in people with Parkinsons disease (PD). Timed up and go test (TUG) has been advocated a useful and reliable tool for quantifying locomotor performance. The aim of this study was to assess the effect of anodal transcranial direct current stimulation (tDCS) applied over the dorsolateral prefrontal cortex (DLPFC) during timed up and go test (TUG) in a group of patients with PD. Ten participants underwent two sessions of anodal tDCS (left and right) and one session of placebo tDCS. TUG was performed before and after each tDCS session (anodal or placebo). A significant motor improvement after right DLPFC stimulation vs. placebo stimulation was observed. These results suggest that anodal tDCS can be a relevant tool to modulate walking abilities in PD.