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Introduction: In a worldwide aging population with a high prevalence of motor and cognitive impairment, it is paramount to improve knowledge about underlying mechanisms of motor and cognitive function and their interplay in the aging processes. Methods: We measured prefrontal cerebral blood flow (CBF) using functional diffuse correlation spectroscopy during motor and dual-task. We aimed to compare CBF changes among 49 older adults with and without mild cognitive impairment (MCI) during a dual-task paradigm (normal walk, 2-forward count walk, 3-backward count walk, obstacle negotiation, and heel tapping). Participants with MCI walked slower during the normal walk and obstacle negotiation compared to participants with normal cognition (NC), while gait speed during counting conditions was not different between the groups, therefore the dual-task cost was higher for participants with NC. We built a linear mixed effects model with CBF measures from the right and left prefrontal cortex. Results: MCI (n = 34) showed a higher increase in CBF from the normal walk to the 2-forward count walk (estimate = 0.34, 95% CI [0.02, 0.66], p = 0.03) compared to participants with NC, related to a right-sided activation. Both groups showed a higher CBF during the 3-backward count walk compared to the normal walk, while only among MCI, CFB was higher during the 2-forward count walk. Discussion: Our findings suggest a differential prefrontal hemodynamic pattern in older adults with MCI compared to their NC counterparts during the dual-task performance, possibly as a response to increasing attentional demand. [ABSTRACT FROM AUTHOR]

Background: Motoric cognitive risk syndrome (MCR) combines slow gait and cognitive complaints and has been proposed as a predementia syndrome. The nature of dual-task performance in MCR has not been established.Objective: To assess differences in dual-task performance between participants with and without MCR and to study the prefrontal cortex (PFC)-based brain activity during dual-task using functional near-infrared spectroscopy.Methods: Cohort study of community-dwelling non-demented older adults included in the "Central Control of Mobility in Aging" study. Comprehensive assessment included global cognition and executive function tests along with clinical variables. Dual-task paradigm consisted in walking while reciting alternate letters of the alphabet (WWT) on an electronic walkway. We compared dual-task performance between MCR (n = 60) and No MCR (n = 478) participants and assessed the relationship of dual-task performance with cognitive function. In a subsample, we compared PFC oxygenation during WWT between MCR (n = 32) and No MCR (n = 293).Results: In our sample of 538 high-functioning older adults (76.6±6.5 years), with 11.2% prevalence of MCR, dual-task cost was not significantly different, compared to No MCR participants. Among MCR participants, no significant relationship was found between WWT velocity and cognitive function, whereas No MCR participants with better cognitive function showed faster WWT velocities. PFC oxygenation during WWT was higher in MCR compared to No MCR (1.02±1.25 versus 0.66±0.83, p = 0.03).Conclusion: MCR participants showed no significant differences in the dual-task cost while exhibiting higher PFC oxygenation during dual-task walking. The dual-task performance (WWT velocity) in MCR participants was not related to cognition. [ABSTRACT FROM AUTHOR]

Background although frailty and delirium are among the most frequent and burdensome geriatric syndromes, little is known about their association and impact on short-term mortality. Objective to examine, in hospitalized older persons, whether frailty is associated with delirium, and whether these two conditions, alone or in combination, affect these patients' 30-day survival. Design observational study nested in the Delirium Day project, with 30-day follow-up. Setting acute medical wards (n  = 118) and rehabilitation wards (n  = 46) in Italy. Subjects a total of 2,065 individuals aged 65+ years hospitalized in acute medical (1,484 patients, 71.9%) or rehabilitation (581 patients, 28.1%) wards. Methods a 25-item Frailty Index (FI) was created. Delirium was assessed using the 4AT test. Vital status was ascertained at 30 days. Results overall, 469 (22.7%) patients experienced delirium on the index day and 82 (4.0%) died during follow-up. After adjustment for potential confounders, each FI score increase of 0.1 significantly increased the odds of delirium (odds ratio, OR: 1.66 [95% CI: 1.45–1.90]), with no difference between the acute (OR: 1.65 [95% CI: 1.41–1.93]) and rehabilitation ward patients (OR: 1.71 [95% CI: 1.27–2.30]). The risk of dying during follow-up also increased significantly for every FI increase of 0.1 in the overall population (OR: 1.65 [95% CI: 1.33–2.05]) and in the acute medical ward patients (OR: 1.61 [95% CI: 1.28–2.04]), but not in the rehabilitation patients. Delirium was not significantly associated with 30-day mortality in either hospital setting. Conclusions in hospitalized older patients, frailty is associated with delirium and with an increased risk of short-term mortality. [ABSTRACT FROM AUTHOR]

The integrity of the frontal areas of the brain, specifically the prefrontal cortex, are critical to preserve cognition and mobility in late life. Prefrontal cortex regions are involved in executive functions and gait control and have been related to the performance of dual-tasks. Dual-task performance assessment may help identify older adults at risk of negative health outcomes. As an alternative to neuroimaging techniques that do not allow assessment during actual motion, functional Near-Infrared Spectroscopy (fNIRS) is a non-invasive technique that can assess neural activation through the measurement of cortical oxygenated and deoxygenated hemoglobin levels, while the person is performing a motor task in a natural environment as well as during cognitive tasks. The aim of this review was to describe the use of fNIRS to study frontal lobe hemodynamics during cognitive, motor and dual-tasks in older adults. From the 46 included publications, 20 studies used only cognitive tasks, three studies used motor tasks and 23 used dual-tasks. Our findings suggest that fNIRS detects changes in frontal activation in older adults (cognitively healthy and mild cognitive impairment), especially while performing cognitive and dual-tasks. In both the comparison between older and younger adults, and in people with different neurological conditions, compared to healthier controls, the prefrontal cortex seems to experience a higher activation, which could be interpreted in the context of proposed neural inefficiency and limited capacity models. Further research is needed to establish standardized fNIRS protocols, study the cerebral hemodynamic in different neurological and systemic conditions that might influence cortical activation and explore its role in predicting incident health outcomes such as dementia. [ABSTRACT FROM AUTHOR]

Sensory deficits are important risk factors for delirium but have been investigated in single-center studies and single clinical settings. This multicenter study aims to evaluate the association between hearing and visual impairment or bi-sensory impairment (visual and hearing impairment) and delirium. Cross-sectional study nested in the 2017 "Delirium Day" project. Patients 65 years and older admitted to acute hospital medical wards, emergency departments, rehabilitation wards, nursing homes, and hospices in Italy. Delirium was assessed with the 4AT (a short tool for delirium assessment) and sensory deficits with a clinical evaluation. We assessed the association between delirium, hearing and visual impairment in multivariable logistic regression models, adjusting for: Model 1, we included predisposing factors for delirium (ie, dementia, weight loss and autonomy in the activities of daily living); Model 2, we added to Model 1 variables, which could be considered precipitating factors for delirium (ie, psychoactive drugs and urinary catheters). A total of 3038 patients were included; delirium prevalence was 25%. Patients with delirium had a higher prevalence of hearing impairment (30.5% vs 18%; P <.001), visual impairment (24.2% vs 15.7%; P <.01) and bi-sensory impairment (16.2% vs 7.5%) compared with those without delirium. In the multivariable logistic regression analysis, the presence of bi-sensory impairment was associated with delirium in Model 1 [odds ratio (OR) 1.5, confidence interval (CI) 1.2–2.1; P =.00] and in Model 2 (OR 1.4; CI 1.1–1.9; P =.02), whereas the presence of visual and hearing impairment alone was not associated with delirium either in Model 1 (OR 0.8; CI 0.6–1.2, P =.36; OR 1.1; CI 0.8–1.4; P =.42) or in Model 2 (OR 0.8, CI 0.6–1.2, P =.27; OR 1.1, CI 0.8–1.4, P =.63). Our findings support the importance of routine screening and specific interventions by a multidisciplinary team to implement optimal management of sensory impairments and hence prevention and the management of the patients with delirium. [ABSTRACT FROM AUTHOR]

Neurologic gait abnormalities (NGA) increase risk for falls and dementia, but their pathophysiologic substrates or association with disability have been poorly investigated. We evaluated the association of NGA with clinical characteristics and functional status in older community-dwellers. Gait characteristics were measured in older community-dwellers without neurological or psychological diseases participating to the Health Aging Body Composition study. NGA were rated using standardized readings of video-recorded short walks, combined with standard neurological exam. We tested cross-sectional associations with demographics, vascular risk factors, comorbidities, cognitive function and disability. Of 177 participants (median age [IQR] = 82 [4] years, 55% women, 58% Caucasian), 49 (27.7%) had NGA. The most prevalent sub-types were unsteady (10.7%), hemiparetic (4.5%) and parkinsonian (4%). In multivariable logistic regression models, diabetes was associated with higher risk (OR = 3.24, 95% CI = 1.38–7.59), whereas higher physical activity (OR = 0.89, 95% CI = 0.80–0.99) and gait speed (OR = 0.04, 95% CI = 0.005–0.27) with lower risk of NGA. Prevalence of NGA was associated with difficulty in at least 1 activity of daily living, adjusting for confounders (OR = 2.90, 95% CI = 1.11–7.58). After adjusting for gait speed, this association was attenuated to non-significance (OR = 2.13, 95% CI = 0.71–6.37). In our sample of community-dwelling older adults without neurological diseases, NGA, detected with a standardized neurological exam, part of usual physicians' training, were common. The relationships with diabetes and reduced physical activity might suggest vascular dysfunction as an underlying contributor to NGA. These results, if confirmed by longitudinal studies, which should also disentangle the relationship between NGA, gait speed and disability, might add information for preventing and managing mobility disability. • An approach based on gait assessment through direct observation is presented. • Despite being free from clinical neurological diseases, 30% of the sample shows qualitative neurologic gait abnormalities. • Gait abnormalities were associated with diabetes and reduced physical activity. • Gait abnormalities were not associated with difficulty in the activities of daily living after adjusting for gait speed. • This gait assessment is easy and inexpensive: it is based on the neurological exam, which is part of physician's training. [ABSTRACT FROM AUTHOR]