Preserved Cognition Research Articles

Dual-task performance in seniors with mild cognitive impairment and Alzheimer’s disease: a longitudinal study

BACKGROUND: Motor performance in older adults with cognitive impairment is worse under dual task conditions, increasing the risk of falls. However, there is a lack of studies that analyze this performance over time in people with different cognitive profiles. AIM: This study aimed to compare the performance of an isolated task and a dual task in people with preserved cognition (PrC), mild cognitive impairment (MCI) and Alzheimer`s disease (AD). METHOD: Data were collected on two occasions (T1; T2), thirty-two months apart. Participants (n=51) were separated between groups: PrC (n=22), MCI (n=19) and AD (n=10). They were analyzed in three situations: 1) isolated motor task - Timed up and go test (TUGT); 2) cognitive-motor test (CMT)– dialing on the phone; 3) dual task (DT). To compare the performance of the dual task between the groups, delta was calculated and the ANCOVA test was applied. RESULTS: Although the cost of the dual task was not significantly different over time in any group, we found increases in the time required to complete the TUGT (p<0.01) and TUGT-DT (p>0.01) after 32 months in the AD group and a reduction in time in the PrC and MCI groups. A greater number of steps in the TUGT-DT (p<0.01) and an increase in cadence in the TUGT (p=0.01) and TUGT-DT (p<0.01) were also found in the AD group. CONCLUSION:We suggest that a more functional task, such as walking while typing on the phone, may be considered a more sensitive way of assessing older adults with AD.

Six-month change in gait speed to discriminate between those with and without falls history in older people with Mild Cognitive Impairment and mild Alzheimer disease

Background and PurposeThe purposes of this study were to identify differences in gait speed performance over 6 months between older people with Preserved Cognition (PrC), with Mild Cognitive Impairment (MCI) and with Alzheimer disease (AD) in mild stage; and to verify if the change in gait speed could discriminate fallers in older people with MCI and AD in a mild stage MethodsA longitudinal study was conducted with community-dwelling older adults, including 40 with PrC, 36 with MCI and 34 with AD in the mild stage. Gait speed (in m/s) changes were captured through a 10-meter walk test. We documented the number of self-reported falls by monthly calendars that were returned after a 6-month follow-up. During this period, the participants received monthly telephone calls to remind them to fill in the calendar ResultsThere was a significant difference in terms of sex and age between the groups: 23%, 31% and 19% were female and had a mean age of 72.8, 75.9 and 76.9 years in the PrC, MCI and AD groups respectively. During the follow-up, 45%, 52.7% and 52.9% of the PrC, MCI and AD groups fell. The MCI and AD groups presented lower gait speed compared to the PrC Group at both moments. There was no significant difference in the change of gait speed between groups. In the model adjusted by age, the change in gait speed failed to discriminate fallers in older people with MCI and with AD ConclusionOlder people with MCI and AD in the mild stage present lower gait speed compared to older people with PrC. Changes in gait speed over a short period of time do not discriminate fallers in older people with MCI or AD in a mild stage.

Changes in executive function and gait in people with mild cognitive impairment and Alzheimer disease.

ABSTRACT.Changes in executive function and motor aspects can compromise the prognosis of older adults with mild cognitive impairment (MCI) and favor the evolution to dementia.Objectives:The aim of this study was to investigate the changes in executive function and gait and to determine the association between changes in these variables.Methods:A 32-month longitudinal study was conducted with 40 volunteers: 19 with preserved cognition (PrC), 15 with MCI and 6 with Alzheimer disease (AD). Executive function and gait speed were assessed using the Frontal Assessment Battery, the Clock-Drawing test and the 10-meter walk test. For data analysis, the Pearson product-moment correlation, two-way repeated-measures ANOVA, and chi-square were conducted.Results:After 32 months, an improvement in the executive function was found in all groups (p=0.003). At baseline, gait speed was slower in individuals with MCI and AD compared to those with PrC (p=0.044), that was maintained after the follow-up (p=0.001). There was significant increase in number of steps in all groups (p=0.001). No significant association was found between changes in gait speed and executive function.Conclusions:It should be taken into account that gait deteriorates prior to executive function to plan interventions and health strategies for this population.

Outcomes and interventions in the elderly with and without cognitive impairment: a longitudinal study.

ABSTRACT.Background:Clinical follow-up studies are necessary for a better understanding of the evolution of cognitive impairment as well as the development of better assessment and intervention tools.Objective:To investigate whether older people with preserved cognition (PC), mild cognitive impairment (MCI) and mild Alzheimer's disease (AD) show differences in clinical outcomes and interventions after a 32-month period.Methods:One hundred twenty-four community-dwelling older people were included and classified in one of three groups (PC, MCI and mild AD). Information on clinical outcomes (deaths, new diagnoses, falls, need for assistance or changes in routine and hospitalizations) and interventions (increased use of medication, physiotherapeutic intervention, practice of physical exercise, etc.) in the 32-month period were collected by telephone or during a home visit on a single day.Results:Ninety-five participants (35 with PC, 33 with MCI and 27 with AD) were reevaluated after 32 months. The need for assistance/changes in routine was significantly higher in the AD group, especially with regard to basic activities of daily living. Unlike the other groups, the PC group did not show “other diagnoses” (urinary incontinence, prolapse, change in vision or autoimmune disease). No significant differences were found regarding other variables.Conclusions:Older people with and without cognitive impairment exhibited differences in some clinical outcomes after 32 months, such as need for assistance or changes in their routine and new diagnoses of specific diseases. Therefore, the multidimensionality of geriatric patients should be considered when planning assessments and interventions.

Performance of an Adapted Version of the Timed Up-and-Go Test in People with Cognitive Impairments

In clinical practice, older people with cognitive impairment may have difficulties to understand the instructions of the Timed Up-and-Go (TUGT) test and present a bad performance. The purpose of this study was to identify differences in the TUGT performance, in an adapted version, between older adults with preserved cognition (PC), mild cognitive impairment (MCI) and Alzheimer's disease (AD), and to identify the association between the adapted TUGT performance and cognition among groups. A cross-sectional study was conducted with 118 community-dwelling older adults divided in three groups: PC (n = 40), MCI (n = 40) and AD (n = 38). The evaluation was composed by the adapted TUGT and cognitive assessment (Addenbrooke's Cognitive Examination and Frontal Assessment Battery). Only the cadence of TUGT presented significant difference between groups, specifically between AD versus MCI and PC groups. The main correlations were found between time of TUGT with fluency domain and global cognitive function, especially in the AD Group. The findings contribute to the understanding of how cognition interferes on functional mobility in older people with MCI and AD. The adapted TUGT is easy to perform in clinical practice and can be useful when assessing mobility in people with cognitive impairment.

Association Between Gait and Dual Task With Cognitive Domains in Older People With Cognitive Impairment

ABSTRACTThe authors investigated whether impaired gait and dual-task performances are associated with specific cognitive domains among older people with preserved cognition (PC), mild cognitive impairment (MCI), and mild Alzheimer's disease (AD). The sample comprised 40 older adults with PC, 40 with MCI, and 38 with mild AD. The assessment consisted of gait (measured by 10-m walk test and Timed Up and Go Test [TUGT]), dual task (measured by TUGT associated with a cognitive-motor task of calling a phone number), and cognition (domains of the Addenbrooke Cognitive Examination–Revised and Frontal Assessment Battery [FAB]). For data analysis, the Pearson product-moment correlation and the backward stepwise linear regression were conducted. Language, fluency, and visuospatial domains predicted the 10-m walk test measure specifically in PC, MCI, and AD groups. Only the visuospatial domain was independently associated with the TUGT measure in the MCI and AD groups. FAB score, language domain, and FAB score and fluency domain were the strongest predictors for the isolated cognitive-motor task measure in the PC, MCI, and AD groups, respectively. The visuospatial domain was independently associated with the dual-task test measure in all 3 groups. The study findings demonstrate the influence of specific cognitive domains in daily mobility tasks in people with different cognitive profiles.