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Introduction: Neurovascular coupling (NVC) is an important mechanism for the regulation of cerebral perfusion during intensive cognitive activity. Thus, it should be examined in terms of its effects on the regulation dynamics of cerebral perfusion and its possible alterations during cognitive impairment. The dynamic dependence of continuous changes in cerebral blood velocity (CBv), which can be measured noninvasively using transcranial Doppler upon fluctuations in arterial blood pressure (ABP) and CO2 tension, using end-tidal CO2 (EtCO2) as a proxy, can be quantified via data-based dynamic modeling to yield insights into two key regulatory mechanisms: the dynamic cerebral autoregulation (dCA) and dynamic vasomotor reactivity (DVR), respectively. Methods: Using the Laguerre Expansion Technique (LET), this study extracted such models from data in supine resting vs cognitively active conditions (during attention, fluency, and memory tasks from the Addenbrooke's Cognitive Examination III, ACE-III) to elucidate possible changes in dCA and DVR due to cognitive stimulation of NVC. Healthy volunteers (n = 39) were recruited at the University of Leicester and continuous measurements of CBv, ABP, and EtCO2 were recorded. Results: Modeling analysis of the dynamic ABP-to-CBv and CO2-to-CBv relationships showed significant changes in dCA, but not DVR, under cognitively active conditions compared to resting state. Discussion: Interpretation of these changes through Principal Dynamic Mode (PDM) analysis is discussed in terms of possible associations between stronger NVC stimulation during cognitive tasks and enhanced sympathetic activation. [ABSTRACT FROM AUTHOR]

Background: Many older people are now living with co‐occurring physical and mental health disorders, but these often managed separately. The aim of this systematic review was to explore integrated physical‐mental health care services available internationally for older people living with mental health diagnoses, and whether these result in improved health outcomes. Methods: Medline, Embase, CINAHL, PsycINFO and Scopus were searched with a predefined search strategy (PROSPERO: CRD42022383824), generating 6210 articles. Studies were included where an integrated physical‐mental health care service model was utilised in a population of older people (aged >60 years) with a mental health diagnosis (including dementia or cognitive impairment) and at least one concomitant physical health condition requiring physical health care input. All studies were assessed for risk of bias (ROB 2.0, ROBINS‐I) and results were synthesised narratively. Results: Nine studies were included across inpatient (n = 6, 1262 patients) and community (n = 3, 466 patients) settings. Studies were rated as low‐moderate risk of bias. These covered joint physical‐mental health wards, liaison services, embedded physicians in mental health wards, and joint multidisciplinary teams. Services with greater integration (e.g., joint wards) had more benefits for patients and carers. There were few benefits to traditional outcomes (e.g., hospital admissions, mortality), but greater care quality, carer satisfaction, and improved mood and engagement were demonstrated. Conclusions: Multidisciplinary integrated care resulted in improvement of a range of health outcomes for older people with combined physical and mental health needs. Larger and more robust studies are needed to explore the development of these service models further, with cost‐effectiveness analyses. [ABSTRACT FROM AUTHOR]

Neurovascular coupling (NVC) is the tight relationship between changes in cerebral blood flow and neural activation. NVC can be evaluated non-invasively using transcranial Doppler ultrasound (TCD)-measured changes in brain activation (cerebral blood velocity [CBv]) using different cognitive tasks and stimuli. This study used a novel approach to analyzing CBv changes occurring in response to 20 tasks from the Addenbrooke's Cognitive Examination III in 40 healthy individuals. The novel approach compared various information entropy families (permutation, Tsallis, and Rényi entropy) and statistical complexity measures based on disequilibrium. Using this approach, we found the majority of the attention, visuospatial, and memory tasks from the Addenbrooke's Cognitive Examination III that showed lower statistical complexity values when compared with the resting state. On the entropy-complexity (HC) plane, a receiver operating characteristic curve was used to distinguish between baseline and cognitive tasks using the area under the curve. Best area under the curve values were 0.91 ± 0.04, p =.001, to distinguish between resting and cognitively active states. Our findings show that brain hemodynamic signals captured with TCD can be used to distinguish between resting state (baseline) and cognitive effort (stimulation paradigms) using entropy and statistical complexity as an alternative method to traditional techniques such as coherent averaging of CBv signals. Further work should directly compare these analysis methods to identify the optimal method for analyzing TCD-measured changes in NVC. [ABSTRACT FROM AUTHOR]

Previous studies report contradicting age‐related neurovascular coupling (NVC). Few studies assess postural effects, but less investigate relationships between age and NVC within different postures. Therefore, this study investigated the effect of age on NVC in different postures with varying cognitive stimuli. Beat‐to‐beat blood pressure, heart rate and end‐tidal carbon dioxide were assessed alongside middle and posterior cerebral artery velocities (MCAv and PCAv, respectively) using transcranial Doppler ultrasonography in 78 participants (31 young‐, 23 middle‐ and 24 older‐aged) with visuospatial (VST) and attention tasks (AT) in various postures at two timepoints (T2 and T3). Between‐group significance testing utilized one‐way analysis‐of‐variance (ANOVA) (Tukey post‐hoc). Mixed three‐way/one‐way ANOVAs explored task, posture, and age interactions. Significant effects of posture on NVC were driven by a 3.8% increase from seated to supine. For AT, mean supine %MCAv increase was greatest in younger (5.44%) versus middle (0.12%) and older‐age (0.09%) at T3 (p = 0.005). For VST, mean supine %PCAv increase was greatest at T2 and T3 in middle (10.99%/10.12%) and older‐age (17.36%/17.26%) versus younger (9.44%/8.89%) (p = 0.004/p = 0.002). We identified significant age‐related NVC effects with VST‐induced hyperactivation. This may reflect age‐related compensatory processes in supine. Further work is required, using complex stimuli while standing/walking, examining NVC, aging and falls. [ABSTRACT FROM AUTHOR]

Prior studies have identified variable effects of aging on neurovascular coupling (NVC). Carbon dioxide (CO2) affects both cerebral blood velocity (CBv) and NVC, but the effects of age on NVC under different CO2 conditions are unknown. Therefore, we investigated the effects of aging on NVC in different CO2 states during cognitive paradigms. Seventy-eight participants (18–78 yr), with well-controlled comorbidities, underwent continuous recordings of CBv by bilateral insonation of middle (MCA) and posterior (PCA) cerebral arteries (transcranial Doppler), blood pressure, end-tidal CO2, and heart rate during poikilocapnia, hypercapnia (5% CO2 inhalation), and hypocapnia (paced hyperventilation). Neuroactivation via visuospatial (VS) and attention tasks (AT) was used to stimulate NVC. Peak percentage and absolute change in MCAv/PCAv, were compared between CO2 conditions and age groups (≤30, 31–60, and >60 yr). For the VS task, in poikilocapnia, younger adults had a lower NVC response compared with older adults [mean difference (MD): −7.92% (standard deviation (SD): 2.37), P = 0.004], but comparable between younger and middle-aged groups. In hypercapnia, both younger [MD: −4.75% (SD: 1.56), P = 0.009] and middle [MD: −4.58% (SD: 1.69), P = 0.023] age groups had lower NVC responses compared with older adults. Finally, in hypocapnia, both older [MD: 5.92% (SD: 2.21), P = 0.025] and middle [MD: 5.44% (SD: 2.27), P = 0.049] age groups had greater NVC responses, compared with younger adults. In conclusion, the magnitude of NVC response suppression from baseline during hyper- and hypocapnia, did not differ significantly between age groups. However, the middle age group demonstrated a different NVC response while under hypercapnic conditions, compared with hypocapnia. NEW & NOTEWORTHY: This study describes the effects of age on neurovascular coupling under altered CO2 conditions. We demonstrated that both hypercapnia and hypocapnia suppress neurovascular coupling (NVC) responses. Furthermore, that middle age exhibits an NVC response comparable with younger adults under hypercapnia, and older adults under hypocapnia. [ABSTRACT FROM AUTHOR]

Background: Agreeing on priority topics for stroke research can help make best use of limited funding, people, and time. Formal priority-setting exercises collate stakeholders' opinions to reach consensus on the most important research questions. Several stroke research priority setting exercises have been published. Exploring commonalities and differences between these exercises could bring a better understanding of priority research topics. Aim: We collated and compared published stroke research priority setting exercises across international healthcare systems. Summary of review: Multidisciplinary, electronic literature databases were searched from 2000 to 2021, using a validated search syntax. Inclusion criteria were: full article; stroke focus (any subtype); prioritization method described; and lists priorities for research. Priorities were extracted, coded, and assigned to categories using thematic analysis. The Nine Common Themes of Good Practice and the Reporting guideline for priority setting of health research checklists were used to assess methodological and reporting quality respectively. From 623 titles assessed, 14 studies were eligible for inclusion, including 2410 participants and describing 165 priorities. The majority of priority setting exercises were conducted in high-income countries (86%, n = 12 articles), published between 2011 and 2021 (64%, n = 9), and included views of healthcare professionals (57%, n = 8), and stroke survivors (50%, n = 7). Caregivers (n = 3, 21%) were under-represented. The James Lind Alliance priority setting method was most commonly used (50%, n = 7). Priorities were grouped into 10 thematic categories. Rehabilitation and follow-up was the most common priority theme (15%, n = 25 priorities), followed by psychological recovery (14%, n = 23), pathology (14%, n = 23), and caregivers and support (14%, n = 23). Priorities differed by year and case-mix (stakeholder group and demographics) of respondents. No article was judged high quality for all aspects of method or reporting. Common limitations were around inclusiveness and evaluation of the exercise. Conclusion: Stroke research priorities are dynamic and context-specific. However, there was a common theme of prioritizing research that considered life after stroke. Future priority settings should consider the inclusion of nonindustrialized countries and stroke survivors with a range of impairments. [ABSTRACT FROM AUTHOR]