Search

Highlights • Brain diseases are not diagnosed based on neurobiological mechanisms • Value may be gained by deep and broad phenotyping across disease states • Attention and working memory are important constructs for assessment • Assay selection across disease states requires significant compromise • Relating psychological construct to functional ability may redefine brain disease Abstract Central nervous system diseases are not currently diagnosed based on knowledge of biological mechanisms underlying their symptoms. Greater understanding may be offered through an agnostic approach to traditional disease categories, where learning more about shared biological mechanisms across conditions could potentially reclassify sub-groups of patients to allow realisation of more effective treatments. This review represents the output of the collaborative group "PRISM", tasked with considering assay choices for assessment of attention and working memory in a transdiagnostic cohort of Alzheimer's disease and schizophrenia patients exhibiting symptomatic spectra of social withdrawal. A multidimensional analysis of this nature has not been previously attempted. Nominated assays (continuous performance test III, attention network test, digit symbol substitution, N-back, complex span, spatial navigation in a virtual environment) reflected a necessary compromise between the need for broad assessment of the neuropsychological constructs in question with several pragmatic criteria: patient burden, compatibility with neurophysiologic measures and availability of preclinical homologues. [ABSTRACT FROM AUTHOR]

Objectives: Anxiety is postulated to be modifiable risk factor for dementia. Our primary aim was to conduct a meta-analysis of community-based cohort studies that investigated the association between anxiety and dementia.Design: We identified relevant, high-quality papers published up to January 2018 by searching PubMed and Web of Science. Prospective cohort studies reporting relative risks (RRs) for the association between anxiety and dementia, adjusted at least for age, were considered eligible. Study-specific RRs were combined using a random-effects model.Results: Six prospective cohorts (reported in 5 studies), with a total of 10,394 participants, were included in the meta-analysis. The pooled RR of 1.29 (95% CI: 1.01-1.66) indicated a significant association between anxiety and dementia.Conclusion: Anxiety significantly increases the risk of dementia. However, further research is needed to determine the extent to which anxiety is a cause of dementia rather than a prodrome or marker. [ABSTRACT FROM AUTHOR]

Social and medical problems associated with stress are increasing globally and seriously affect mental health and well-being. However, an effective stress-level monitoring method is still not available. This paper presents a quantitative method for monitoring acute stress levels in healthy young people using biomarkers from physiological signals that can be unobtrusively monitored. Two states were induced to 40 volunteers, a basal state generated with a relaxation task and an acute stress state generated by applying a standard stress test that includes five different tasks. Standard psychological questionnaires and biochemical markers were utilized as ground truth of stress levels. A multivariable approach to comprehensively measure the physiological stress response is proposed using stress biomarkers derived from skin temperature, heart rate, and pulse wave signals. Acute physiological stress levels (total-range 0-100 au) were continuously estimated every 1 min showing medians of 29.06 au in the relaxation tasks, while rising from 34.58 to 47.55 au in the stress tasks. Moreover, using the proposed method, five statistically different stress levels induced by the performed tasks were also measured. Results obtained show that, in these experimental conditions, stress can be monitored from unobtrusive biomarkers. Thus, a more general stress monitoring method could be derived based on this approach. Graphical abstract Stress measurements of different healthy young people throughout a Stress Session that includes a pre-relax stage (BLs), memory test (ST and MT), stress anticipation time (SA), video display (VD) and arithmetic task. [ABSTRACT FROM AUTHOR]

Objectives: To test the hypothesis that differences by gender will be observed in the association of hip fracture risk with stages of cognitive impairment; and to explore the association between Petersen's "mild cognitive impairment" (MCI) and DSM-5 "mild neurocognitive disorder" (MND).Study Design: A community sample of 4803 individuals aged 55+ years was assessed in a two-phase case-finding enquiry in Zaragoza, Spain, and was followed up for 16 years. Medical and psychiatric history was collected with standardized instruments, including the Mini-Mental Status Examination (MMSE), Geriatric Mental State (GMS), History and Aetiology Schedule, and a Risk Factors Questionnaire. The statistical analysis included calculations of Hazard Ratios (HR) in multivariate Cox proportional hazards regression models.Main Outcome Measures: Identified cases of hip fracture, validated by blind researchers.Results: In men, hip fracture risk was increased at the "mild" (HR=4.99 (1.39-17.91)) and at the "severe" (HR=9.31 (1.35-64.06)) stages of cognitive impairment, indicated by MMSE performance. In contrast, in women no association could be documented at the "mild stage" (power=89%), and the association disappeared altogether at the "severe stage" in the final multivariate statistical model (power 100%). No association observed between hip fracture and mild cognitive impairment in both men (power=28% for P-MCI) and women (power=44% and 19% for Petersen's MCI and DSM-5 MND, respectively).Conclusions: Increased hip fracture risk was associated with "mild" stages of cognitive impairment in men, but not in women. To explore the potential association with the construct MCI or MND, studies with greater statistical power would be required. [ABSTRACT FROM AUTHOR]

Retinal nerve fiber layer thickness (RNFL) measured by means of Optical Coherence Tomography (OCT) has been used as a marker not only of ophthalmologic diseases but also of neurodegenerative diseases such as Alzheimer's disease (AD) and mild cognitive impairment (MCI). The purpose of this work was to demonstrate that patients with amnestic MCI show an intermediate RNFL thickness between normality and AD, and a macular volume and thickness as well. In a cross-sectional study we consecutively recruited 18 patients with AD, 21 with MCI, and 41 healthy controls. OCT was performed in all of them to measure circumpapillary RNFL thickness in µm, as well as macular volume and thickness. In the analysis of variance we saw that RNFL was thinner in MCI patients compared with controls, and it was also thinner in AD patients compared with MCI patients and controls. With regard to the macular measurements in mm, MCI patients had the greatest macular volume in comparison with AD patients and controls. In turn the controls had greater macular volume than AD patients. The decreased RNFL thickness in MCI and AD patients suggests loss of retinal neurons and their axons. The increased thickness and macular volume have never been reported before in aMCI. This finding could be explained by inflammation and/or gliosis in early stages of AD. OCT could be a useful marker of AD for early detection and monitoring progression. [ABSTRACT FROM AUTHOR]