Associations between brain structure and dual decline in gait and cognition.

Dual decline in gait and cognition is associated with an increased risk of dementia, with combined gait and memory decline exhibiting the strongest association. To better understand the underlying pathology, we investigated the associations of baseline brain structure with dual decliners using three serial gait speed and cognitive assessments in memory, processing speed-attention, and verbal fluency. Participants (n=267) were categorized based on annual decline in gait speed and cognitive measures. Lower gray and white matter volume and higher white matter hyperintensity volume increased the risk of being a dual decliner in gait and both the memory and processing speed-attention groups (all p < 0.05). Lower hippocampal volume (p = 0.047) was only associated with dual decline in gait and memory group. No brain structures were correlated with dual decline in gait and verbal fluency. These results suggest that neurodegenerative pathology and white matter hyperintensities are involved in dual decline in gait and both memory and processing speed-attention. Smaller hippocampal volume may only contribute to dual decline in gait and memory.

White matter fiber morphology in persisting postconcussive symptoms and posttraumatic headache after pediatric concussion: a fixel-based analysis.

OBJECTIVE: Posttraumatic headache (PTH) represents the most common acute and persistent postconcussive symptom (PCS) in children after concussion, yet there remains a lack of valid and objective biomarkers to facilitate risk stratification and early intervention in this patient population. Fixel-based analysis of diffusion-weighted imaging, which overcomes constraints of traditional diffusion tensor imaging analyses, can improve the sensitivity and specificity of detecting white matter changes postconcussion. The aim of this study was to investigate whole-brain and tract-based differences in white matter morphology, including fiber density (FD) and fiber bundle cross-section (FC) area in children with PCSs and PTH at 2 weeks after concussion. METHODS: This prospective longitudinal study recruited children aged 5-18 years who presented to the emergency department of a tertiary pediatric hospital with a concussion sustained within the previous 48 hours. Participants underwent diffusion-weighted MRI at 2 weeks postinjury. Whole-brain white matter statistical analysis was performed at the level of each individual fiber population within an image voxel (fixel) to compute FD, FC, and a combined metric (FD and bundle cross-section [FDC]) using connectivity-based fixel enhancement. Tract-based Bayesian analysis was performed to examine FD in 23 major white matter tracts. RESULTS: Comparisons of 1) recovered (n = 27) and symptomatic (n = 16) children, and those with 2) PTH (n = 13) and non-PTH (n = 30; overall mean age 12.99 ± 2.70 years, 74% male) found no fiber-specific white matter microstructural differences in FD, FC, or FDC at 2 weeks postconcussion, when adjusting for age and sex (family-wise error rate corrected p value > 0.05). Tract-based Bayesian analysis showed evidence of no effect of PTH on FD in 10 major white matter tracts, and evidence of no effect of recovery group on FD in 3 white matter tracts (Bayes factor < 1/3). CONCLUSIONS: Using whole-brain fixel-wise and tract-based analyses, these findings indicate that fiber-specific properties of white matter microstructure are not different between children with persisting PCSs compared with recovered children 2 weeks after concussion. These data extend the limited research on white matter fiber-specific morphology while overcoming limitations inherent to traditional diffusion models. Further validation of our findings with a large-scale cohort is warranted.

Interactions between age, sex and visceral adipose tissue on brain ageing.

AIM: To examine the associations between visceral adipose tissue (VAT) and brain structural measures at midlife and explore how these associations may be affected by age, sex and cardiometabolic factors. METHODS: We used abdominal and brain magnetic resonance imaging data from a population-based cohort of people at midlife in the UK Biobank. Regression modelling was applied to study associations of VAT volume with total brain volume (TBV), grey matter volume (GMV), white matter volume, white matter hyperintensity volume (WMHV) and total hippocampal volume (THV), and whether these associations were altered by age, sex or cardiometabolic factors. RESULTS: Complete data were available for 17 377 participants (mean age 63 years, standard deviation = 12, 53% female). Greater VAT was associated with lower TBV, GMV and THV (P < .001). We found an interaction between VAT and sex on TBV (P < .001), such that the negative association of VAT with TBV was greater in men (ß = -2.89, 95% confidence interval [CI] -2.32 to -10.15) than in women (ß = -1.32, 95% CI -0.49 to -3.14), with similar findings for GMV. We also found an interaction between VAT and age (but not sex) on WMHV (P < .001). The addition of other cardiometabolic factors or measures of physical activity resulted in little change to the models. CONCLUSIONS: VAT volume is associated with poorer brain health in midlife and this relationship is greatest in men and those at younger ages.

Updates to the Melbourne Children's Regional Infant Brain Software Package (M-CRIB-S).

The delineation of cortical areas on magnetic resonance images (MRI) is important for understanding the complexities of the developing human brain. The previous version of the Melbourne Children's Regional Infant Brain (M-CRIB-S) (Adamson et al. Scientific Reports, 10(1), 10, 2020) is a software package that performs whole-brain segmentation, cortical surface extraction and parcellation of the neonatal brain. Available cortical parcellation schemes in the M-CRIB-S are the adult-compatible 34- and 31-region per hemisphere Desikan-Killiany (DK) and Desikan-Killiany-Tourville (DKT), respectively. We present a major update to the software package which achieves two aims: 1) to make the voxel-based segmentation outputs derived from the Freesurfer-compatible M-CRIB scheme, and 2) to improve the accuracy of whole-brain segmentation and cortical surface extraction. Cortical surface extraction has been improved with additional steps to improve penetration of the inner surface into thin gyri. The improved cortical surface extraction is shown to increase the robustness of measures such as surface area, cortical thickness, and cortical volume.

Healthcare consumer acceptability of routine use of the EQ-5D-5L in clinical care: a cross-sectional survey.

PURPOSE: Patient reported outcome measures, such as the EQ-5D-5L, provide a measure of self-perceived health status or health-related quality of life. Understanding the consumer acceptability of a patient reported outcome measure can help to decide about its implementation across a healthcare organisation and possibly increase the likelihood of its use in clinical care. This study established the acceptability of the EQ-5D-5L from the perspective of clients receiving healthcare, and determined if acceptability varied by client sub-types. METHODS: A cross-sectional survey explored clients' experience of the EQ-5D-5L. Eligible clients were aged ≥ 18 years and completed the EQ-5D-5L on admission and discharge to one of two multi-disciplinary community health services. Likert scale items explored acceptability, and open-ended questions determined if the EQ-5D-5L reflects experience of illness. Associations between acceptability and client characteristics were established using χ2 test. Open-ended questions were analysed using content analysis. RESULTS: Most of the 304 clients (mean age 70 years, SD 16) agreed that the EQ-5D-5L: was easy to use/understand (n = 301, 99%) and useful (n = 289, 95%); improved communication with their therapist (n = 275, 90%); and made them feel more in control of their health (n = 276, 91%). Most clients also agreed that they wished to continue using the EQ-5D-5L (n = 285, 93%). Clients aged ≥ 60 years reported lower acceptability. Clients noted that the EQ-5D-5L did not capture experience of illness related to fatigue, balance/falls, cognition, and sleep. CONCLUSION: The EQ-5D-5L is acceptable for use in care but does not capture all aspects of health relevant to clients, and acceptability varies by subgroup.

Type 2 Diabetes and Biomarkers of Brain Structure, Perfusion, Metabolism, and Function in Late Mid-Life: A Multimodal Discordant Twin Study.

BACKGROUND: Type 2 diabetes (T2D) is associated with an increased risk of dementia and early features may become evident even in mid-life. Characterizing these early features comprehensively requires multiple measurement modalities and careful selection of participants with and without T2D. OBJECTIVE: We conducted a cross-sectional multimodal imaging study of T2D-discordant twins in late mid-life to provide insights into underlying mechanisms. METHODS: Measurements included computerized cognitive battery, brain MRI (including arterial spin labelling, diffusion tensor, resting state functional), fluorodeoxyglucose (FDG)-PET, and retinal optical coherence tomography. RESULTS: There were 23 pairs, mean age 63.7 (±6.1) years. In global analyses, T2D was associated with poorer attention (ß= -0.45, p <0.001) and with reduced FDG uptake (ß= -5.04, p = 0.02), but not with cortical thickness (p = 0.71), total brain volume (p = 0.51), fractional anisotropy (p = 0.15), mean diffusivity (p = 0.34), or resting state activity (p = 0.4). Higher FDG uptake was associated with better attention (ß= 3.19, p = 0.01) but not with other cognitive domains. In regional analyses, T2D was associated with lower accumbens volume (ß= -44, p = 0.0004) which was in turn associated with poorer attention. CONCLUSION: T2D-related brain dysfunction in mid-life manifests as attentional loss accompanied by evidence of subtle neurodegeneration and global reduction in cerebral metabolism, in the absence of overt cerebrovascular disease.

Cortical growth from infancy to adolescence in preterm and term-born children.

Early life experiences can exert a significant influence on cortical and cognitive development. Very preterm birth exposes infants to several adverse environmental factors during hospital admission, which affect cortical architecture. However, the subsequent consequence of very preterm birth on cortical growth from infancy to adolescence has never been defined; despite knowledge of critical periods during childhood for establishment of cortical networks. Our aims were to: chart typical longitudinal cortical development and sex differences in cortical development from birth to adolescence in healthy term-born children; estimate differences in cortical development between children born at term and very preterm; and estimate differences in cortical development between children with normal and impaired cognition in adolescence. This longitudinal cohort study included children born at term (≥37 weeks' gestation) and very preterm (<30 weeks' gestation) with MRI scans at ages 0, 7 and 13 years (n = 66 term-born participants comprising 34 with one scan, 18 with two scans and 14 with three scans; n = 201 very preterm participants comprising 56 with one scan, 88 with two scans and 57 with three scans). Cognitive assessments were performed at age 13 years. Cortical surface reconstruction and parcellation were performed with state-of-the-art, equivalent MRI analysis pipelines for all time points, resulting in longitudinal cortical volume, surface area and thickness measurements for 62 cortical regions. Developmental trajectories for each region were modelled in term-born children, contrasted between children born at term and very preterm, and contrasted between all children with normal and impaired cognition. In typically developing term-born children, we documented anticipated patterns of rapidly increasing cortical volume, area and thickness in early childhood, followed by more subtle changes in later childhood, with smaller cortical size in females than males. In contrast, children born very preterm exhibited increasingly reduced cortical volumes, relative to term-born children, particularly during ages 0-7 years in temporal cortical regions. This reduction in cortical volume in children born very preterm was largely driven by increasingly reduced cortical thickness rather than area. This resulted in amplified cortical volume and thickness reductions by age 13 years in individuals born very preterm. Alterations in cortical thickness development were found in children with impaired language and memory. This study shows that the neurobiological impact of very preterm birth on cortical growth is amplified from infancy to adolescence. These data further inform the long-lasting impact on cortical development from very preterm birth, providing broader insights into neurodevelopmental consequences of early life experiences.

Using a multi-stakeholder co-design process to develop a health service organisation-wide patient reported outcome measure collection system.

PURPOSE: Limited examples exist of successful Patient Reported Outcome Measure (PROM) implementation across an entire healthcare organisation. The aim of this study was to use a multi-stakeholder co-design process to develop a PROM collection system, which will inform implementation of routine collection of PROMs across an entire healthcare organisation. METHODS: Co-design comprised semi-structured interviews with clinicians (n = 11) and workshops/surveys with consumers (n = 320). The interview guide with clinicians focused on their experience using PROMs, preferences for using PROMs, and facilitators/barriers to using PROMs. Co-design activities specific to consumers focused on: (1) how PROMs will be administered (mode), (2) when PROMs will be administered (timing), (3) who will assist with PROMs collection, and (4) how long a PROM will take to complete. Data were analysed using a manifest qualitative content analysis approach. RESULTS: Core elements identified during the co-design process included: PROMs collection should be consumer-led and administered by someone other than a clinician; collection at discharge from the healthcare organisation and at 3-6 months post discharge would be most suitable for supporting comprehensive assessment; PROMs should be administered using a variety of modes to accommodate the diversity of consumer preferences, with electronic as the default; and the time taken to complete PROMs should be no longer than 5-10 min. CONCLUSION: This study provides new information on the co-design of a healthcare organisation-wide PROM collection system. Implementing a clinician and patient informed strategy for PROMs collection, that meets their preferences across multiple domains, should address known barriers to routine collection.

Exploring associations of greenery, air pollution and walkability with cardiometabolic health in people at midlife and beyond.

AIM: To examine associations of neighborhood greenery, air pollution and walkability with cardiometabolic disease in adults aged ≥45 years in the Frankston-Mornington Peninsula region, Victoria, Australia. METHODS: A cross-sectional, ecological study design was used. We assessed mean annual neighborhood greenery using the Normalized Difference Vegetation Index; air pollution (fine particulate matter of diameter ≤2.5 µm [PM2.5] and NO2) using land-use regression models; and walkability using Walk Score (possible values 0-100). Medically diagnosed diabetes (~95% type-2), heart disease and stroke were self-reported in the Australian Census (2021). Multivariable regression was used to model associations between environmental exposures and area-level (neighborhood) cardiometabolic disease prevalence (age group ≥45 years), with socioeconomic status, age and sex as covariates. Air pollution was examined as a mediator of associations between greenery and disease prevalence. RESULTS: Our sample comprised 699 neighborhoods with the following mean (SD) values: Normalized Difference Vegetation Index 0.47 (0.09), PM2.5, 8.5 (0.6) µg/m3 and NO2, 5.2 (1.6) ppb. Disease prevalences were: heart disease, mean 8.9% (4.5%); diabetes, mean 10.3% (4.7%); and stroke, median 1.2% (range 0-10.9%). Greenery was negatively associated with diabetes (ß = -5.85, 95% CI -9.53, -2.17) and stroke prevalence (ß = -1.26, 95% CI -2.11, -0.42). PM2.5 and NO2 were positively associated with diabetes (ß = 1.59, 95% CI 1.00, 2.18; ß = 0.42, 95% CI 0.22, 0.62) and stroke prevalence (ß = 0.15, 95% CI 0.01, 0.29; ß = 0.06, 95% CI 0.01, 0.10). The association between greenery and diabetes was partially mediated by PM2.5 (mediated effect -5.38, 95% CI -7.84, -3.03). CONCLUSIONS: Greenery and air pollutants were associated with lower and higher prevalence, respectively, of self-reported diabetes and, to a lesser extent, stroke. These ecological findings require further exploration with stronger, longitudinal study designs to inform public health policy and directions. Geriatr Gerontol Int 2024; 24: 208-214.

Type of anesthesia for cancer resection surgery: No differential impact on cancer recurrence in mouse models of breast cancer.

BACKGROUND: Surgery is essential for curative treatment of solid tumors. Evidence from recent retrospective clinical analyses suggests that use of propofol-based total intravenous anesthesia during cancer resection surgery is associated with improved overall survival compared to inhaled volatile anesthesia. Evaluating these findings in prospective clinical studies is required to inform definitive clinical guidelines but will take many years and requires biomarkers to monitor treatment effect. Therefore, we examined the effect of different anesthetic agents on cancer recurrence in mouse models of breast cancer with the overarching goal of evaluating plausible mechanisms that could be used as biomarkers of treatment response. METHODS: To test the hypothesis that volatile anesthesia accelerates breast cancer recurrence after surgical resection of the primary tumor, we used three mouse models of breast cancer. We compared volatile sevoflurane anesthesia with intravenous propofol anesthesia and used serial non-invasive bioluminescent imaging to track primary tumor recurrence and metastatic recurrence. To determine short-term perioperative effects, we evaluated the effect of anesthesia on vascular integrity and immune cell changes after surgery in animal models. RESULTS: Survival analyses found that the kinetics of cancer recurrence and impact on survival were similar regardless of the anesthetic agent used during cancer surgery. Vascular permeability, immune cell infiltration and cytokine profiles showed no statistical difference after resection with inhaled sevoflurane or intravenous propofol anesthesia. CONCLUSIONS: These preclinical studies found no evidence that choice of anesthetic agent used during cancer resection surgery affected either short-term perioperative events or long-term cancer outcomes in mouse models of breast cancer. These findings raise the possibility that mouse models do not recapitulate perioperative events in cancer patients. Nonetheless, the findings suggest that future evaluation of effects of anesthesia on cancer outcomes should focus on cancer types other than breast cancer.

Developing a linked electronic health record derived data platform to support research into healthy ageing.

Introduction: Digitalisation of Electronic Health Record (EHR) data has created unique opportunities for research. However, these data are routinely collected for operational purposes and so are not curated to the standard required for research. Harnessing such routine data at large scale allows efficient and long-term epidemiological and health services research. Objectives: To describe the establishment a linked EHR derived data platform in the National Centre for Healthy Ageing, Melbourne, Australia, aimed at enabling research targeting national health priority areas in ageing. Methods: Our approach incorporated: data validation, curation and warehousing to ensure quality and completeness; end-user engagement and consensus on the platform content; implementation of an artificial intelligence (AI) pipeline for extraction of text-based data items; early consumer involvement; and implementation of routine collection of patient reported outcome measures, in a multisite public health service. Results: Data for a cohort of >800,000 patients collected over a 10-year period have been curated within the platform's research data warehouse. So far 117 items have been identified as suitable for inclusion, from 11 research relevant datasets held within the health service EHR systems. Data access, extraction and release processes, guided by the Five Safes Framework, are being tested through project use-cases. A natural language processing (NLP) pipeline has been implemented and a framework for the routine collection and incorporation of patient reported outcome measures developed. Conclusions: We highlight the importance of establishing comprehensive processes for the foundations of a data platform utilising routine data not collected for research purposes. These robust foundations will facilitate future expansion through linkages to other datasets for the efficient and cost-effective study of health related to ageing at a large scale.

Development of an implementation strategy for routine collection of generic patient reported outcome measures: a qualitative study in multidisciplinary community rehabilitation.

PURPOSE: To explore staff perceptions of barriers and enablers towards implementing the EQ-5D-5L in community rehabilitation, and develop a theory-informed implementation approach for routine administration of generic patient-reported outcome measures (PROMs) using implementation science frameworks. MATERIALS AND METHODS: A qualitative study was conducted at three sites. Multidisciplinary rehabilitation staff completed individual semi-structured interviews, which were transcribed and coded against the Theoretical Domains Framework (TDF). We identified and selected potentially effective behaviour change techniques using the Behavior Change Wheel. Hypothetical strategies were operationalised. RESULTS: Twenty-one interviews were conducted, and four themes emerged: (1) The Impact of PROMs on patient centered-care; (2) Considerations for validity of PROMs; (3) Service-level impact of embedding PROMs; (4) Practical issues of embedding PROMs within the service. Barriers and enablers were mapped to seven of the TDF domains; relating most to clinicians' "belief about consequences", "reinforcement", and "environmental context and resources". Five hypothetical strategies were developed to overcome identified barriers and strengthen enablers. Key behaviour change techniques underpinning the strategies include: restructuring the physical environment, incentivisation, persuasion and education, enablement, and, social support. CONCLUSIONS: Our implementation approach highlights the importance of automating processes, engaging site champions, routinely reporting, and using PROM data to inform service provision.

Implementation of patient reported outcome measures within multidiscipline rehabilitation settings are likely optimised by establishing infrastructure support e.g., information technology systems to automate the process and minimise manual aspects of data collection.Engaging site champions may be an important enabler for the routine collection of patient reported outcome measuresProviding feedback to clinicians on aggregated results of patient reported outcome measures are likely to motivate and encourage routine collection.

Association of Acute Infarct Topography With Development of Cerebral Palsy and Neurologic Impairment in Neonates With Stroke.

BACKGROUND AND OBJECTIVES: Research investigating neonatal arterial ischemic stroke (NAIS) outcomes have shown that combined cortical and basal ganglia infarction or involvement of the corticospinal tract predict cerebral palsy (CP). The research question was whether voxel-based lesion-symptom mapping (VLSM) on acute MRI can identify brain regions associated with CP and neurodevelopmental impairments in NAIS. METHODS: Newborns were recruited from prospective Australian and Swiss pediatric stroke registries. CP diagnosis was based on clinical examination. Language and cognitive-behavioral impairments were assessed using the Pediatric Stroke Outcome Measure, dichotomized to good (0-0.5) or poor (≥1), at ≥18 months of age. Infarcts were manually segmented using diffusion-weighted imaging, registered to a neonatal-specific brain template. VLSM was conducted using MATLAB SPM12 toolbox. A general linear model was used to correlate lesion masks with motor, language, and cognitive-behavioral outcomes. Voxel-wise t-statistics were calculated, correcting for multiple comparisons using family-wise error (FWE) rate. RESULTS: Eighty-five newborns met the inclusion criteria. Infarct lateralization was left hemisphere (62%), right (8%), and bilateral (30%). At a median age of 2.1 years (interquartile range 1.9-2.6), 33% developed CP and 42% had neurologic impairments. Fifty-four grey and white matter regions correlated with CP (t > 4.33; FWE < 0.05), including primary motor pathway regions, such as the precentral gyrus, and cerebral peduncle, and regions functionally connected to the primary motor pathway, such as the pallidum, and corpus callosum motor segment. No significant correlations were found for language or cognitive-behavioral outcomes. DISCUSSION: CP after NAIS correlates with infarct regions directly involved in motor control and in functionally connected regions. Areas associated with language or cognitive-behavioral impairment are less clear.

Acceptability of the routine use and collection of a generic patient reported outcome measure from the perspective of healthcare staff: a qualitative study.

BACKGROUND: Patient-reported outcome measures (PROMs) provide a measure of self-perceived health status or health-related quality of life. They have been used to support provider-patient decisions, healthcare delivery, and value-based healthcare models. A barrier to routine collection of PROMs is the perception that PROMs lack clinical utility. As such, it is important to establish clinicians' acceptability of the PROM prior to large-scale implementation. This study explored the acceptability of the routine use and collection of a generic PROM in healthcare services from the perspective of healthcare staff. METHODS: Individual semi-structured interviews were completed from September 2020 to March 2021 with 26 staff from two multi-disciplinary community healthcare services in Melbourne, Australia. Interviews explored their experiences of using the EQ-5D-5L in their routine care. Interviews were recorded and transcribed verbatim. Data were analysed according to a framework approach, using inductive and deductive techniques. RESULTS: Participants discussed the acceptability of the EQ-5D-5L with reference to four themes: practicalities of use; holistic nature; influence on client care; and influence on health service. Participants found the EQ-5D-5L quick and easy to administer, and appreciated that it measured multiple domains of health that were relevant to their clients' care. They believed the EQ-5D-5L helped to identify client problems, and inform service delivery. They also reported features that were less acceptable, including a lack of item specificity to some healthcare disciplines. Participants reported the challenge of managing conflict between their assessment of the client's health and the client's perspective of their own health, leading some to question whether the client could provide an accurate reflection of their own health. CONCLUSIONS: The EQ-5D-5L has several features that healthcare staff viewed as acceptable for routine collection and use in healthcare. Training on the validity of the patient reported perspective and broadening the scope of PROMs collection beyond the EQ-5D-5L should be considered to facilitate large-scale implementation.

Association between brain health outcomes and metabolic risk factors in persons with diabetes.

We performed a cross-sectional study to determine associations between cognition and MRI-derived brain outcomes, with obesity, diabetes duration, and metabolic risk factors in 51 Pima American Indians with longstanding type 2 diabetes (T2d) (mean [SD] age: 48.4 [11.3] years, T2d duration: 20.1 [9.1] years). Participants had similar cognition (NIH Toolbox Cognition Battery composite: 45.3 [9.8], p = 0.64, n = 51) compared to normative data. T2d duration, but not other metabolic risk factors, associated with decreased cortical thickness (Point Estimate (PE): -0.0061, 95%CI: -0.0113, -0.0009, n = 45), gray matter volume (PE: -830.39, 95%CI: -1503.14, -157.64, n = 45), and increased white matter hyperintensity volume (PE: 0.0389, 95%CI: 0.0049, 0.0729, n = 45).

Some children with idiopathic toe walking display sensory processing difficulties but not all: A systematic review.

AIM: Idiopathic toe walking (ITW) is a diagnosis for children who toe walk without another diagnosis known to cause toe walking. Recent research has suggested that children with ITW may have mild motor planning challenges and sensory processing differences. The primary aim of this systematic review was to determine whether children diagnosed with ITW have differences in their sensory processing compared to typically developing children. Secondary aims included determining how sensory processing was assessed in this population and documenting the broad clinometric and psychometric properties of any assessment tools. METHODS: MEDLINE, CINAHL, AMED and Embase were searched for relevant literature in English. Studies were eligible for inclusion if they described children aged 3 and 18 with idiopathic toe walking and reported a sensory processing domain. RESULTS: Twelve articles met the inclusion criteria; however, only two papers included data permitting meta-analysis. Meta-analyses of vibration perception threshold using a random effect model were not significant (p = 0.31). Other data were synthesised by narrative and showed a high heterogeneity across multiple sensory processing domains. CONCLUSION: This study highlights that despite children with ITW often conceptualised as possessing sensory processing challenges, there is little evidence supporting this theory. Further research on sensory processing in children with this gait pattern is necessary.

Effect of alteplase, benzodiazepines and beta-blocker on post-stroke pneumonia: Exploration of VISTA-Acute.

BACKGROUND: Post-stroke pneumonia is a frequent complication of stroke and is associated with high mortality. Investigators have described its associations with beta-blocker. However, there has been no evaluation of the role of recombinant tissue plasminogen activator (RTPA). We postulate that RTPA may modify the effect of stroke on pneumonia by reducing stroke disability. We explore this using data from neuroprotection trials in Virtual International Stroke Trials Archive (VISTA)-Acute. METHOD: We evaluated the impact of RTPA and other medications in random forest model. Random forest is a type of supervised ensemble tree-based machine learning method. We used the standard approach for performing random forest and partitioned the data into training (70%) and validation (30%) sets. This action enabled to the model developed on training data to be evaluated in the validation data. We borrowed idea from Coalition Game Theory on fair distribution of marginal profit (Shapley value) to determine proportional contribution of a covariate to the model. Consistent with other analysis using the VISTA-Acute data, the diagnosis of post-stroke pneumonia was based on reports of serious adverse events. RESULTS: The overall frequency of pneumonia was 10.9% (614/5652). It was present in 11.5% of the RTPA (270/2358) and 10.4% (344/3295) of the no RTPA groups. There was significant (p<0.05) imbalance in covariates (age, baseline National Institutes of Health Stroke Scale (NIHSS), diabetes, and sex). The AUC for training data was 0.70 (95% CI 0.65-0.76), validation data was 0.67 (95% CI 0.62-0.73). The Shapley value shows that baseline NIHSS (≥10) and age (≥80) made the largest contribution to the model of pneumonia while absence of benzodiazepine may protect against pneumonia. RTPA and beta-blocker had very low effect on frequency of pneumonia. CONCLUSION: In this cohort pneumonia was strongly associated with stroke severity and age whereas RTPA had a much lower effect. An intriguing finding is a possible association between benzodiazepine and pneumonia but this requires further evaluation.

Cerebral blood flow in children with persisting postconcussive symptoms and posttraumatic headache at 2 weeks postconcussion.

OBJECTIVE: Persisting postconcussive symptoms (pPCS), particularly headache, can significantly disrupt children's recovery and functioning. However, the underlying pathophysiology of these symptoms remains unclear. The goal in this study was to determine whether pPCS are related to cerebral blood flow (CBF) at 2 weeks postconcussion. The authors also investigated whether variations in CBF can explain the increased risk of acute posttraumatic headache (PTH) in female children following concussion. METHODS: As part of a prospective, longitudinal study, the authors recruited children 5-18 years old who were admitted to the emergency department of a tertiary pediatric hospital with a concussion sustained within 48 hours of admission. Participants underwent pseudocontinuous arterial spin labeling MRI at 2 weeks postconcussion to quantify global mean gray and white matter perfusion (in ml/100 g/min). Conventional frequentist analysis and Bayesian analysis were performed. RESULTS: Comparison of recovered (n = 26) and symptomatic (n = 12) groups (mean age 13.15 years, SD 2.69 years; 28 male) found no differences in mean global gray and white matter perfusion at 2 weeks postconcussion (Bayes factors > 3). Although female sex was identified as a risk factor for PTH with migraine features (p = 0.003), there was no difference in CBF between female children with and without PTH. CONCLUSIONS: Global CBF was not associated with pPCS and female PTH at 2 weeks after pediatric concussion. These findings provide evidence against the use of CBF measured by arterial spin labeling as an acute biomarker for pediatric concussion recovery.

Oronasal vs Nasal Masks: The Impact of Mask Type on CPAP Requirement, Pharyngeal Critical Closing Pressure (Pcrit), and Upper Airway Cross-Sectional Areas in Patients With OSA.

BACKGROUND: CPAP delivered via an oronasal mask is associated with lower adherence, higher residual apnea-hypopnea index (AHI), and increased CPAP therapeutic pressure compared with nasal masks. However, the mechanisms underlying the increased pressure requirements are not well understood. RESEARCH QUESTION: How do oronasal masks affect upper airway anatomy and collapsibility? STUDY DESIGN AND METHODS: Fourteen patients with OSA underwent a sleep study with both a nasal and oronasal mask, each for one-half of the night (order randomized). CPAP was manually titrated to determine therapeutic pressure. Upper airway collapsibility was assessed using the pharyngeal critical closing pressure (Pcrit) technique. Cine MRI was done to dynamically assess the cross-sectional area of the retroglossal and retropalatal airway throughout the respiratory cycle with each mask interface. Scans were repeated at 4 cm H2O and at the nasal and oronasal therapeutic pressures. RESULTS: The oronasal mask was associated with higher therapeutic pressure requirements (ΔM ± SEM; +2.6 ± 0.5; P < .001) and higher Pcrit (+2.4 ± 0.5 cm H2O; P = .001) compared with the nasal mask. The change in therapeutic pressure between masks was strongly correlated with the change in Pcrit (r2 = 0.73; P = .003). Increasing CPAP increased both the retroglossal and retropalatal airway dimensions across both masks. After controlling for pressure and breath phase, the retropalatal cross-sectional area was moderately larger when using a nasal vs an oronasal mask (+17.2 mm2; 95% CI, 6.2-28.2, P < .001) while nasal breathing. INTERPRETATION: Oronasal masks are associated with a more collapsible airway than nasal masks, which likely contributes to the need for a higher therapeutic pressure.