Age-dependent association of white matter abnormality with cognition after TIA or minor stroke

ObjectiveTo investigate if the association between MRI-detectable white matter hyperintensity (WMH) and cognitive status reported in previous studies persists at older ages (>80 years), when some white matter abnormality is almost universally reported in clinical practice.MethodsConsecutive eligible patients from a population-based cohort of all TIA/nondisabling stroke (Oxford Vascular Study) underwent multimodal MRI, including fluid-Attenuated inversion recovery and diffusion-weighted imaging, allowing automated measurement of WMH volume, mean diffusivity (MD), and fractional anisotropy (FA) in normal-Appearing white matter using FSL tools. These measures were related to cognitive status (Montreal Cognitive Assessment) at age 6480 vs >80 years.ResultsOf 566 patients (mean [range] age 66.7 [20-102] years), 107 were aged >80 years. WMH volumes and MD/FA were strongly associated with cognitive status in patients aged 6480 years (all p < 0.001 for WMH, MD, and FA) but not in patients aged >80 years (not significant for WMH, MD, and FA), with age interactions for WMH volume (pinteraction = 0.016) and MD (pinteraction = 0.037). Voxel-wise analyses also showed that lower Montreal Cognitive Assessment scores were associated with frontal WMH in patients 6480 years, but not >80 years.ConclusionMRI markers of white matter damage are strongly related to cognition in patients with TIA/minor stroke at younger ages, but not at age >80 years. Clinicians and patients should not overinterpret the significance of these abnormalities at older ages

A Comparison of Cranial Cavity Extraction Tools for Non-contrast Enhanced CT Scans in Acute Stroke Patients

Cranial cavity extraction is often the first step in quantitative neuroimaging analyses. However, few automated, validated extraction tools have been developed for non-contrast enhanced CT scans (NECT). The purpose of this study was to compare and contrast freely available tools in an unseen dataset of real-world clinical NECT head scans in order to assess the performance and generalisability of these tools. This study included data from a demographically representative sample of 428 patients who had completed NECT scans following hospitalisation for stroke. In a subset of the scans (n = 20), the intracranial spaces were segmented using automated tools and compared to the gold standard of manual delineation to calculate accuracy, precision, recall, and dice similarity coefficient (DSC) values. Further, three readers independently performed regional visual comparisons of the quality of the results in a larger dataset (n = 428). Three tools were found; one of these had unreliable performance so subsequent evaluation was discontinued. The remaining tools included one that was adapted from the FMRIB software library (fBET) and a convolutional neural network- based tool (rBET). Quantitative comparison showed comparable accuracy, precision, recall and DSC values (fBET: 0.984 ± 0.002; rBET: 0.984 ± 0.003; p = 0.99) between the tools; however, intracranial volume was overestimated. Visual comparisons identified characteristic regional differences in the resulting cranial cavity segmentations. Overall fBET had highest visual quality ratings and was preferred by the readers in the majority of subject results (84%). However, both tools produced high quality extractions of the intracranial space and our findings should improve confidence in these automated CT tools. Pre- and post-processing techniques may further improve these results. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12021-021-09534-7

Factors associated with admission to bed-based care : observational prospective cohort study in a multidisciplinary same day emergency care unit (SDEC)

Background. The development of ambulatory emergency care services, now called ‘Same Day Emergency Care’ (SDEC) has been advocated to provide sustainable high quality healthcare in an ageing population. However, there are few data on SDEC and the factors associated with successful ambulatory care in frail older people. We therefore undertook a prospective observational study to determine i) the clinical characteristics and frailty burden of a cohort in an SDEC designed around the needs of older patients and ii) the factors associated with hospital admission within 30-days after initial assessment. Methods. The study setting was the multidisciplinary Abingdon Emergency Medical Unit (EMU) located in a community hospital and led by a senior interface physician (geriatrician or general practitioner). Consecutive patients from August-December 2015 were assessed using a structured paper proforma including cognitive/delirium screen, comorbidities, functional, social, and nutritional status. Physiologic parameters were recorded. Illness severity was quantified using the Systemic Inflammatory Response Syndrome (SIRS>1). Factors associated with hospitalization within 30-days were determined using multivariable logistic regression. Results. Among 533 patients (median (IQR) age=81 (68-87), 315 (59%) female), 453 (86%) were living at home but 283 (54%) required some form of care and 299 (56%) had Barthel85 years." Severe illness was present in 148 (28%) with broadly similar rates across age groups. Overall, 210 (39%) patients had a hospital admission within 30-days with higher rates in older patients: 96 (87%) of 85 years (p<0.0001). Factors independently associated with hospital admission were severe illness (SIRS/point, OR=1.46,95% CI=1.15-1.87, p=0.002) and markers of frailty: delirium (OR=11.28,3.07-41.44,p<0.0001), increased care needs (OR=3.08,1.55-6.12,p=0.001), transport requirement (OR=1.92,1.13-3.27), and poor nutrition (OR=1.13-3.79,p=0.02). Conclusions. Even in an SDEC with a multidisciplinary approach, rates of hospital admission in those with severe illness and frailty were high. Further studies are required to understand the key components of hospital bed-based care that need to be replicated by models delivering acute frailty care closer to home, and the feasibility, cost-effectiveness and patient/carer acceptability of such models

Sepsis recognition tools in acute ambulatory care::associations with process of care and clinical outcomes in a service evaluation of an Emergency Multidisciplinary Unit in Oxfordshire

To assess the performance of currently available sepsis recognition tools in patients referred to a community-based acute ambulatory care unit.Service evaluation of consecutive patients over a 4-month period.Community-based acute ambulatory care unit.Observations, blood results and outcome data were analysed from patients with a suspected infection. Clinical features at first assessment were used to populate sepsis recognition tools including: systemic inflammatory response syndrome (SIRS) criteria, National Early Warning Score (NEWS), quick Sequential Organ Failure Assessment (qSOFA) and National Institute for Health and Care Excellence (NICE) criteria. Scores were assessed against the clinical need for escalated care (use of intravenous antibiotics, fluids, ongoing ambulatory care or hospital treatment) and poor clinical outcome (all-cause mortality and readmission at 30 days after index assessment).Of 533 patients (median age 81 years), 316 had suspected infection with 120 patients requiring care escalated beyond simple community care. SIRS had the highest positive predictive value (50.9%, 95% CI 41.6% to 60.3%) and negative predictive value (68.9%, 95% CI 62.6% to 75.3%) for the need for escalated care. Both NEWS and SIRS were better at predicting the need for escalated care than qSOFA and NICE criteria in patients with suspected infection (all P<0.001). While new-onset confusion predicted the need for escalated care for infection in patients ≥85 years old (n=114), 23.7% of patients ≥85 years had new-onset confusion without evidence for infection.Acute ambulatory care clinicians should use caution in applying the new NICE endorsed criteria for determining the need for intravenous therapy and hospital-based location of care. NICE criteria have poorer performance when compared against NEWS and SIRS and new-onset confusion was prevalent in patients aged ≥85 years without infection

The Electroweak Chiral Lagrangian and CP-Violating Effects in Technicolor Theories

We estimate the CP-violating $WW\gamma$ and $WWZ$ anomalous form factors, arising from CP-violating interactions in extended technicolor theories, and discuss their future experimental detectability. The electric dipole moment of the $W$ boson is found to be as large as {\cal O}(10^{-21}) \; \mbox{e cm}. We connect the CP-odd $WW\gamma$ and $WWZ$ couplings to the corresponding CP-violating electroweak chiral lagrangian operators. The electric dipole moments of the neutron and the electron in technicolor theories are estimated to be as large as {\cal O}(10^{-26}) \; \mbox{e cm} and {\cal O}(10^{-29}) \; \mbox{e cm} respectively. We also suggest the potential to observe large CP-violating technicolor effects in the decay $t \rightarrow b + W^+$.Comment: 34 pages, YCTP-P9-94, LaTex. (minor changes in wording and notation, the figures are appended at the end as one postscript file

Gravitational depolarization of ultracold neutrons: comparison with data

We compare the expected effects of so-called gravitationally enhanced depolarization of ultracold neutrons to measurements carried out in a spin-precession chamber exposed to a variety of vertical magnetic-field gradients. In particular, we have investigated the dependence upon these field gradients of spin-depolarization rates and also of shifts in the measured neutron Larmor precession frequency. We find excellent qualitative agreement, with gravitationally enhanced depolarization accounting for several previously unexplained features in the data

Experts' Judgments of Management Journal Quality:An Identity Concerns Model

Many lists that purport to gauge the quality of journals in management and organization studies (MOS) are based on the judgments of experts in the field. This article develops an identity concerns model (ICM) that suggests that such judgments are likely to be shaped by the personal and social identities of evaluators. The model was tested in a study in which 168 editorial board members rated 44 MOS journals. In line with the ICM, respondents rated journal quality more highly to the extent that a given journal reflected their personal concerns (associated with having published more articles in that journal) and the concerns of a relevant ingroup (associated with membership of the journal’s editorial board or a particular disciplinary or geographical background). However, judges’ ratings of journals in which they had published were more favorable when those journals had a low-quality reputation, and their ratings of journals that reflected their geographical and disciplinary affiliations were more favorable when those journals had a high-quality reputation. The findings are thus consistent with the view that identity concerns come to the fore in journal ratings when there is either a need to protect against personal identity threat or a meaningful opportunity to promote social identity

Long term incidence of dementia, predictors of mortality and pathological diagnosis in older stroke survivors

Greater understanding of the risk factors and mechanisms of incident dementia in stroke survivors is needed for prevention and management. There is limited information on the long-term consequences and forms of incident dementia in older stroke survivors. We recruited 355 patients aged >75 years from hospital-based stroke registers into a longitudinal study 3 months after stroke. At baseline none of the patients had dementia. Patients were genotyped for apolipoprotein E and assessed annually for cognition and development of incident dementia over up to 8 years of follow-up. The effect of baseline vascular risk factors upon incidence of dementia and mortality were estimated by Cox proportional regression analyses adjusted for age and gender. Standard neuropathological examination was performed to diagnose the first 50 cases that came to autopsy. We found that the median survival from the date of the index stroke was 6.72 years (95% confidence intervals: 6.38–7.05). During the follow-up of a mean time of 3.79 years, 23.9% of subjects were known to have developed dementia and 76.1% remained alive without dementia or died without dementia. The incidence of delayed dementia was calculated to be 6.32 cases per 100 person years whereas that for death or dementia was 8.62. Univariate and multivariate regression analyses showed that the most robust predictors of dementia included low (1.5 standard deviations below age-matched control group) baseline Cambridge Cognitive Examination executive function and memory scores, Geriatric Depression Scale score and three or more cardiovascular risk factors. Autopsy findings suggested that remarkably ≥75% of the demented stroke survivors met the current criteria for vascular dementia. Demented subjects tended to exhibit marginally greater neurofibrillary pathology including tauopathy and Lewy bodies and microinfarcts than non-demented survivors. Despite initial improvements in cognition following stroke in older stroke survivors, risk of progression to delayed dementia after stroke is substantial, but is related to the presence of vascular risk factors. Careful monitoring and treatment of modifiable vascular risk factors may be of benefit in preventing post-stroke dementia in the general population

Revised experimental upper limit on the electric dipole moment of the neutron

We present for the first time a detailed and comprehensive analysis of the experimental results that set the current world sensitivity limit on the magnitude of the electric dipole moment (EDM) of the neutron. We have extended and enhanced our earlier analysis to include recent developments in the understanding of the effects of gravity in depolarizing ultracold neutrons; an improved calculation of the spectrum of the neutrons; and conservative estimates of other possible systematic errors, which are also shown to be consistent with more recent measurements undertaken with the apparatus. We obtain a net result of dn=−0.21±1.82×10−26  e cm, which may be interpreted as a slightly revised upper limit on the magnitude of the EDM of 3.0×10−26  e cm (90% C.L.) or 3.6×10−26  e cm (95% C.L.)

Model Analysis of Time Reversal Symmetry Test in the Caltech Fe-57 Gamma-Transition Experiment

The CALTECH gamma-transition experiment testing time reversal symmetry via the E2/M1 mulipole mixing ratio of the 122 keV gamma-line in Fe-57 has already been performed in 1977. Extending an earlier analysis in terms of an effective one-body potential, this experiment is now analyzed in terms of effective one boson exchange T-odd P-even nucleon nucleon potentials. Within the model space considered for the Fe-57 nucleus no contribution from isovector rho-type exchange is possible. The bound on the coupling strength phi_A from effective short range axial-vector type exchange induced by the experimental bound on sin(eta) leads to phi_A < 10^{-2}.Comment: 5 pages, RevTex 3.