Journal of Alzheimer's Disease - Volume 71, issue s1

Authors: Montero-Odasso, Manuel | Perry, George

Article Type: Editorial

DOI: 10.3233/JAD-190790

Citation: Journal of Alzheimer's Disease, vol. 71, no. s1, pp. S1-S4, 2019

Authors: Jayakody, Oshadi | Breslin, Monique | Srikanth, Velandai K. | Callisaya, Michele L.

Article Type: Research Article

Abstract: Background: Gait impairments are emerging predictors of dementia. However, few studies have examined whether gait predicts decline in specific cognitive domains. Objective: This study aimed to determine whether gait speed or other gait characteristics were associated with decline in specific cognitive domains and the role of the ApoE4 genotype in modifying these associations. Methods: Participants (n  = 410; mean age 72.0±7.0 years) were randomly selected from the electoral roll. At baseline, gait speed was assessed using the GAITRite walkway. Gait variability in step time, step length, step width, and double support time (DST) was calculated as the …standard deviation of each measure across all steps. In a subsample (n  = 177), speed was measured under fast pace. The difference between usual and fast pace was calculated. At baseline, 2.6 and 4.6 years processing speed, memory, executive and visuospatial function were measured using neuropsychological tests. Multivariable mixed models were used to examine 1) associations between gait and the different cognitive domains over time and 2) whether the presence of ApoE4 genotype modified these associations. Results: Higher DST variability was associated with greater decline in memory (p for interaction 0.03). Slow gait speed predicted decline in processing speed (p  = 0.02) and visuospatial function (p  = 0.03). In ApoE4 carriers, gait speed also predicted decline in memory (p  = 0.02). Other gait characteristics did not predict decline in any of the cognitive domains (p  > 0.05). Conclusions: These findings add to the evidence that gait is an early indicator of cognitive decline, but that specific gait measures may provide diagnostic insights into specific cognitive domains. Show more

Keywords: Apolipoprotein E4, cognitive dysfunction, gait variability, specific cognitive domains, walking speed, walking speed reserve

DOI: 10.3233/JAD-181157

Citation: Journal of Alzheimer's Disease, vol. 71, no. s1, pp. S5-S14, 2019

Authors: Toots, Annika T.M. | Taylor, Morag E. | Lord, Stephen R. | Close, Jacqueline C.T.

Article Type: Research Article

Abstract: Background: While gait has been linked with cognition, few studies have contrasted the strength of the relationships between gait speed and cognitive domains in people with cognitive impairment (CI). Objectives: Investigate the association between gait speed and global cognitive function and cognitive domains in older people with CI. Method: Three-hundred-and-nine community-dwelling people with CI (mean age 82 years, 47% female, and mean gait speed 0.62±0.23 m/s) were included using baseline data from the Intervention-Falls in Older Cognitively Impaired Study (iFOCIS). Usual gait speed (m/s) was measured over 2.4 m. Global cognitive function and individual cognitive domains (attention; …memory; verbal fluency; language; visuospatial ability) were assessed using the Addenbrooke’s Cognitive Examination-III (ACE-III). Additionally, executive function was assessed using the Frontal Assessment Battery (FAB). Results: Participants mean±standard deviation ACE-III and FAB scores were 62.8±19.3 and 11.4±4.6, respectively. In separate multiple linear regression analyses adjusting for confounders, global cognitive function, and each cognitive domain, was significantly associated with gait speed. Executive function demonstrated the strongest association (FAB: standardized β= 0.278, p  < 0.001, adjusted R2  = 0.431), and remained significantly associated with gait speed when adjusted for attention, memory, language, and visuospatial ability. Conclusion: In this large study of older people with CI, global cognition and each cognitive domain were associated with gait speed. Executive function had the strongest association, possibly reflecting the higher-level cognitive processes and complex motor task responses required for gait control. Future longitudinal studies are needed to explore the temporal relationships between declines in executive function and gait, and whether the facilitation of executive function lessens gait decline. Show more

Keywords: Aged, cognition, dementia, executive function, gait, walking speed

DOI: 10.3233/JAD-181173

Citation: Journal of Alzheimer's Disease, vol. 71, no. s1, pp. S15-S21, 2019

Authors: Langeard, Antoine | Houdeib, Ramzi | Saillant, Kathia | Kaushal, Navin | Lussier, Maxime | Bherer, Louis

Article Type: Research Article

Abstract: Age-related mobility and cognitive declines are closely linked, but their relationship is complex and needs to be further investigated. The study aimed to test if cognition (processing speed, inhibition and switching performances) mediates the age-related difference in mobility. Mediation analyses were used to test whether processing speed, inhibition and switching performances on the Stroop test independently mediate the relationship between age and performances at the Timed Up and Go (TUG). Results revealed that only switching performances mediated the age-related difference in TUG (65.1% of the total effect) supporting the notion that executive control plays a critical role in older adults’ …mobility. Show more

Keywords: Aging, cognition, gait, inhibition, locomotion, mediation

DOI: 10.3233/JAD-181176

Citation: Journal of Alzheimer's Disease, vol. 71, no. s1, pp. S23-S28, 2019

Authors: Allali, Gilles | Montembeault, Maxime | Saj, Arnaud | Wong, Chek Hooi | Cooper-Brown, Liam Anders | Bherer, Louis | Beauchet, Olivier

Article Type: Research Article

Abstract: Background: Gait impairment is observed in early stages of dementia, such as mild cognitive impairment (MCI), and is associated with morphological brain volume changes like atrophy. Objective: This study aims to characterize the brain’s grey matter (GM) volume covariance associated with gait speed in patients with amnestic mild cognitive impairment (aMCI) and non-amnestic MCI (naMCI). Methods: Gait speed was measured in 171 patients with MCI (age 72.0±5.1; 36.8% female; 41 with aMCI and 130 naMCI) at normal and rapid gait speeds. Brain GM covariance networks were computed using voxel-based morphometry, using the main neural correlates of …gait speed in each group and for each walking condition as seed regions. Results: Normal gait speed correlated with GM volume in the left frontal cortex in patients with aMCI, and in bilateral caudate and left putamen in those with naMCI. Rapid gait speed correlated with GM volume in the bilateral caudate and right cerebellum in naMCI, but without any GM region in aMCI. For normal gait speed, the left caudate nucleus volume in naMCI covaried with subcortico-frontal regions, while the left frontal cortex covaried with cortical regions involving the frontal cortex in aMCI. For rapid gait speed, subcortico-frontal regions were similar as for normal speed in naMCI. Conclusion: Brain GM volume covariance associated with gait speed varies according to the type of MCI; it involved subcortico-frontal regions for patients with naMCI and the frontal cortex in those with aMCI. Show more

Keywords: Alzheimer’s disease, anatomical structural covariance, gait, mild cognitive impairment, neuroimaging

DOI: 10.3233/JAD-190038

Citation: Journal of Alzheimer's Disease, vol. 71, no. s1, pp. S29-S39, 2019

Authors: Dao, Elizabeth | Hsiung, Ging-Yuek Robin | Sossi, Vesna | Tam, Roger | Shahinfard, Elham | Nicklin, Eloise | Al Keridy, Walid | Liu-Ambrose, Teresa

Article Type: Research Article

Abstract: Background: Impaired physical function (i.e., slowing of gait, muscle weakness, and poor mobility) is common in older adults with cognitive impairment and dementia. Evidence suggests that cerebral small vessel disease, specifically white matter lesions (WMLs), is associated with impaired physical function, but little research has been conducted to understand the specific role of Alzheimer’s disease pathology in physical outcomes. Objective: The objective of this study was to examine the association between cerebral amyloid-β (Aβ) deposition and physical function in people with cognitive impairment. Methods: Thirty participants completed an 11 C Pittsburgh compound B (PIB) position emission …tomography (PET) scan to quantify global Aβ deposition using standardized uptake value ratio (SUVR). We assessed usual gait speed, muscle strength of the lower extremities, balance, and functional mobility using the Short Physical Performance Battery (SPPB) and the Timed Up and Go Test (TUGT). Multiple linear regression analyses examined the association between Aβ and each measure of physical function, adjusting for age, body mass index, and WML load. Results: Global PIB SUVR was significantly associated with usual gait speed (β= –0.52, p  = 0.01) and SPPB performance (β= –0.47, p  = 0.02), such that increased Aβ deposition was associated with reduced performance on both measures. Global PIB SUVR was not significantly associated with TUGT performance (β= 0.32, p  = 0.08). Conclusions: Cerebral Aβ deposition is associated with reduced gait speed, muscle strength, and balance in older adults with cognitive impairment independent of WML load. However, Aβ deposition was not associated with functional mobility. Show more

Keywords: Alzheimer’s disease, amyloid-β , mild cognitive impairment, mobility, physical function

DOI: 10.3233/JAD-180848

Citation: Journal of Alzheimer's Disease, vol. 71, no. s1, pp. S41-S49, 2019

Authors: Nocera, Joe R. | Arsik, Idil | Keskinocak, Pinar | Lepley-Flood, Amy | Lah, James J. | Levey, Allan I. | Esper, Gregory J.

Article Type: Short Communication

Abstract: There is increasing interest in gait evaluations in clinical settings given the associations between gait and health outcomes. However, efforts examining implementation of gait evaluation in neurological clinics are lacking. Herein, gait implementation within a cognitive neurology clinic is presented. Over a 21-month period, a gait evaluation was collected on 81% of eligible patients (n  = 2,622; mean age 73.2±9.5; age range 49–94 years; 47% female). Patients and staff reported being satisfied with the gait assessment. These finding have implications for gait evaluations in clinical settings and for clinical research aimed at understanding the impact of cognitive symptomatology on gait.

Keywords: Cognition, dementia, gait, implementation

DOI: 10.3233/JAD-190106

Citation: Journal of Alzheimer's Disease, vol. 71, no. s1, pp. S51-S55, 2019

Authors: Cullen, Stephanie | Borrie, Michael | Carroll, Susan | Sarquis-Adamson, Yanina | Pieruccini-Faria, Frederico | McKay, Scott | Montero-Odasso, Manuel

Article Type: Research Article

Abstract: Background: Poor dual-task gait (walking while performing a cognitively demanding task) has been linked to progression to dementia in older adults with mild cognitive impairment (MCI). However, many of these findings come from research environments; gait performance across the cognitive spectrum has not previously been studied in a clinical setting. Objective: To examine whether patients from a memory clinic show differences in usual and dual-task gait speed and dual-task cost (DTC) based on cognitive diagnosis. Methods: Patients in the Aging Brain and Memory Clinic (London, ON) performed a usual gait walk and three dual-task gait walks: …counting backwards by ones, naming animals, and counting backwards by seven (serial sevens) out loud. Patients were timed with a stopwatch over a six-meter path marked on the floor. One-way ANOVA was performed to evaluate associations between gait speed and DTC (%) across groups. Results: One hundred ninety-four patients with subjective cognitive impairment (SCI; n  = 46), MCI (n  = 77), or dementia (n  = 71) were assessed. Performance in usual (p  < 0.001) and dual-task gait speed (counting gait p  < 0.001; naming animals p  < 0.001; serial sevens p  = 0.004) decreased across the spectrum of cognitive impairment. Patients with dementia had significantly higher DTC in both counting gait (p  = 0.02) and naming animals (p  = 0.04) conditions compared with patients with SCI and MCI, who had statistically similar DTC in all conditions. Conclusion: Dual-task gait performance significantly declines across the cognitive spectrum in a clinical setting. Dual-task gait testing may be used in conjunction with traditional assessments for diagnosing cognitive impairments. Show more

Keywords: Aging, cognition, dual-task gait, gait

DOI: 10.3233/JAD-181196

Citation: Journal of Alzheimer's Disease, vol. 71, no. s1, pp. S57-S64, 2019

Authors: Rosso, Andrea L. | Metti, Andrea L. | Faulkner, Kimberly | Redfern, Mark | Yaffe, Kristine | Launer, Lenore | Elizabeth Shaaban, C. | Nadkarni, Neelesh K. | Rosano, Caterina

Article Type: Research Article

Abstract: Background: Performance on complex walking tasks may provide a screen for future cognitive decline. Objective: To identify walking tasks that are most strongly associated with subsequent cognitive decline. Methods: Community-dwelling older adults with Modified Mini-Mental State (3MS) >85 at baseline (n  = 223; mean age = 78.7, 52.5% women, 25.6% black) completed usual-pace walking and three complex walking tasks (fast-pace, narrow-path, visuospatial dual-task). Slope of 3MS scores for up to 9 subsequent years (average = 5.2) were used to calculate a cognitive maintainer (slope ≥0) or decliner (slope <0) outcome variable. Logistic regression models assessed associations between gait speeds and being …a cognitive decliner. A sensitivity analysis in a subsample of individuals (n  = 66) confirmed results with adjudicated mild cognitive impairment (MCI) or dementia at 8-9 years post-walking assessment. Results: Cognitive decliners were 52.5% of the sample and on average were slower for all walking tasks compared to maintainers. In models adjusted for demographic and health variables, faster fast-pace (OR = 0.87 per 0.1 m/s, 95% CI: 0.78, 0.97) and dual-task (OR = 0.84 per 0.1 m/s, 95% CI: 0.73, 0.96) gait speeds were associated with lower likelihood of being a cognitive decliner. Usual-pace gait speed was not associated (OR = 0.96 per 0.1 m/s, 95% CI: 0.85, 1.08). Results were nearly identical in analyses with adjudicated MCI or dementia as the outcome. Conclusion: Fast-pace and dual-task walking may provide simple and effective tools for assessing risk for cognitive decline in older individuals with high cognitive function. Such screening tools are important for strategies to prevent or delay onset of clinically meaningful change. Show more

Keywords: Cognitive disorders, epidemiology, geriatrics, walking speed

DOI: 10.3233/JAD-181140

Citation: Journal of Alzheimer's Disease, vol. 71, no. s1, pp. S65-S73, 2019

Authors: Åhman, Hanna Bozkurt | Giedraitis, Vilmantas | Cedervall, Ylva | Lennhed, Björn | Berglund, Lars | McKee, Kevin | Kilander, Lena | Rosendahl, Erik | Ingelsson, Martin | Åberg, Anna Cristina

Article Type: Research Article

Abstract: Background: Tools to identify individuals at preclinical stages of dementia disorders are needed to enable early interventions. Alterations in dual-task performance have been detected early in progressive neurodegenerative disorders. Hence, dual-task testing may have the potential to screen for cognitive impairment caused by neurodegeneration. Exploring correlations between dual-task performance and biomarkers of neurodegeneration is therefore of interest. Objective: To investigate correlations between Timed Up-and-Go dual-task (TUGdt) outcomes and Alzheimer’s disease (AD) cerebrospinal fluid (CSF) biomarkers amyloid-β 42 (Aβ42 ), total tau (t-tau), and phosphorylated tau (p-tau). Methods: This cross-sectional cohort study included 90 participants (age range …49–84 years) undergoing memory assessment, who were subsequently diagnosed with AD, other dementia disorders, mild cognitive impairment, or subjective cognitive impairment. TUG combined with “Naming Animals” (TUGdt NA) and “Months Backwards” (TUGdt MB), respectively, were used to assess dual-task performance. The number of correct words and time taken to complete the tests were measured. The CSF biomarkers were analysed by ELISA. Spearman’s rank correlation was used for analyses between TUGdt outcomes (TUGdt NA and TUGdt MB), and CSF biomarkers, adjusted for age, gender, and educational level. Results: The number of correct words, as well as the number of correct words/10 s during TUGdt NA correlated negatively to CSF t-tau and p-tau. No correlations were found between any time scores and CSF biomarkers. Conclusion: The correlations between TUGdt NA and t-tau and p-tau may indicate that neurodegeneration affects dual-task performance. Longitudinal studies are needed to further explore dual-task testing in screening for cognitive impairment due to neurodegeneration. Show more

Keywords: Alzheimer’s disease, attention, biomarkers, cerebrospinal fluid, dementia, executive function, gait, mild cognitive impairment, subjective cognitive impairment

DOI: 10.3233/JAD-181265

Citation: Journal of Alzheimer's Disease, vol. 71, no. s1, pp. S75-S83, 2019