Functional limitations in older adults who have cognitive impairment without dementia

'With or without you': associations between noteworthy events and cognitive complaints across 100 days

OBJECTIVES

Daily noteworthy events have implications for physical and mental health, but less is known about the role daily events have for self-reported cognition and whether the involvement of close social partners differentiates these associations. The current study examined how daily positive and negative noteworthy events relate to subjective memory and attentional difficulties and whether close social partners moderated associations.

METHOD

We used data from a 100-day microlongitudinal web-based study of 104 older adults (Nobservations=7,051; Mage=63.13 years, SDage=7.81, 88.46% Female). Participants reported on exposure to and valence of noteworthy events, involvement of close social partners, and subjective cognitive complaints at the end of each day.

RESULTS

Logistic multilevel models revealed that days with a negative event were associated with increased odds of forgetting something and trouble concentrating whereas days with positive events were associated with decreased odds of trouble concentrating. Close social partner involvement did not moderate within-person associations.

CONCLUSION

Our results suggest that day-to-day events are correlates of cognitive complaints regardless of close social partner involvement in the events. Research should clarify the role of daily positive and negative events in personalized interventions and determine whether this person-centered approach to self-reported cognitive health helps inform diagnostic practices.

The Association between Untreated and Treated Hearing Loss and Cognitive Performance in Men and Women Aged 60-96 Years: Data from the Swedish "Good Aging in Skåne" Population Study

Background/Objectives: Recent decades have witnessed a sharp increase in research investigating the association between hearing loss and cognitive impairment. Few previous studies have stratified for sex when investigating this issue, where results were inconsistent and require further clarification. Thus, the objective was to investigate the association between self-reported hearing loss and levels of cognitive impairment, stratified for sex. Methods: In this cross-sectional study, data were collected from 2001 to 2016. The study sample consisted of 5075 individuals, 2325 (45.8%) men, mean age 68.3 years, and 2750 (54.2%) women, mean age 70.0 years. Multiple variate ordinal regression models were constructed and adjusted for age, marital status, education, physical activity, depressive mood, hypertension, stroke, diabetes, and use of sedatives to investigate associations between groups of self-reported untreated and treated hearing loss and those reporting no hearing loss in relation to levels of cognitive impairment assessed by the Mini-Mental State Examination scale. Results: In men, treated hearing loss was associated with levels of cognitive impairment, odds ratio (OR) = 1.64, 95% confidence interval (CI) = 1.14-2.36. In women, both untreated hearing loss, (OR = 1.45, CI 1.07-1.98) and treated hearing loss (OR= 1.46, CI 1.06-2.04) were associated with levels of cognitive impairment. Conclusions: Hearing loss was found to be associated with cognitive impairment despite hearing aid use as well as awareness amongst physicians. The introduction of screening programs for hearing loss in older adults could be a crucial step for earlier identification of individuals at higher risk of developing cognitive impairment and dementia.

Cognitive Function Remains Associated With Functional Impairment in Profound Dementia: Alzheimer Disease and Dementia With Lewy Bodies

Background and Objectives

The Baylor Profound Mental Status Examination (BPMSE) was developed to assess cognitive function in the profound stage of dementia. The Clinical Dementia Rating (CDR) scale has been widely used in measuring functional performance in dementia. We aimed to determine whether cognitive function is related to overall functional impairment in profound dementia.

Methods

We selected 864 patients with probable Alzheimer disease (AD) and 25 patients with possible dementia with Lewy Bodies (DLB) cases with profound dementia by Mini-Mental Status Examination or/and clinical global impression. We used BPMSE to measure cognitive function and the CDR sum-of-boxes (CDR-SB) score to determine overall functional status. We used Spearman rank order correlation to examine the univariate association between CDR-SB and BPMSE in the 2 diagnostic groups separately and multivariable regression analysis to investigate whether BPMSE remained associated with functional status after adjustment for age, sex, education, and APOE ε4 genotype. We expected to see an inverse correlation between BPMSE and CDR-SB scores based on the directionality of the rating scale scoring.

Results

In both AD and DLB, total BPMSE scores had a significant inverse correlation with CDR-SB scores (AD: r = -0.453, p < 0.001; DLB: r = -0.489, p = 0.013). It is of interest that in DLB, the "attention" domain of BPMSE had the strongest association with CDR-SB (r = -0.700, p < 0.001) compared with other domains. The multivariable regression models showed that higher BPMSE scores (i.e., better cognitive function) remained significantly correlated with lower CDR-SB scores (i.e., better global function) in AD (CDR-SB: β = -0.340, p < 0.001), but the regression coefficient for BPMSE did not reach significance in the DLB model (CDR-SB: β = -0.298, p = 0.174).

Discussion

In patients with AD and DLB who enter the profound dementia stage, cognitive function is associated with the severity of functional impairment. The lack of significance for DLB in multivariable regression could be due to small sample size because the correlation magnitude is similar to that in AD.

Testing Bidirectionality in Associations of Awareness of Age-Related Gains and Losses With Physical, Mental, and Cognitive Functioning Across 1 Year: The Role of Age

OBJECTIVES

The bidirectionality between self-perceptions of aging and health-related outcomes may depend on age group. Therefore, we tested such bidirectionality among individuals in late midlife (50-64 years), young-old age (65-74 years), and old-old age (75+ years), taking advantage of the construct of Awareness of Age-Related Change (AARC) and its 2-dimensionality in terms of AARC-gains and AARC-losses. Various conceptualizations of physical, mental, and cognitive functioning were used as outcomes.

METHODS

Data from 2 measurement occasions (2019 and 2020) from the UK PROTECT study for individuals in late midlife (N = 2,385), young-old age (N = 2,430), and old-old age (N = 539) were used. Data on self-reported functional difficulties, depression, anxiety, and performance on four computerized cognitive tasks (i.e., verbal reasoning, paired associate learning, self-ordered search, and digit span) providing a score for verbal reasoning and a score for working memory were analyzed using cross-lagged panel models.

RESULTS

Across all 3 age groups, the bidirectional associations of AARC-gains with indicators of functioning were not significant, whereas higher AARC-losses significantly predicted slightly greater functional difficulties and higher depression and anxiety levels. Higher AARC-losses predicted slightly poorer Verbal Reasoning only in old-old age and poorer Working Memory predicted slightly higher AARC-losses only in young-old age. The remaining associations of AARC-losses with cognitive tasks were not statistically significant.

DISCUSSION

In accordance with previous research targeting other indicators of self-perceptions of aging, this study supported a stronger impact of AARC-losses on indicators of physical functioning and mental health than vice versa from midlife to old-old age.

Determinants of semantic and episodic memory decline among older adults in Ghana: Evidence from the WHO study on global AGEing and adult health Ghana wave 2

Objective

Determined factors associated with semantic (SM) and episodic memory (EM) among older adults aged 50 years and older in Ghana.

Methods

Data from WHO Study on Global AGEing and Adult Health (SAGE) Ghana Wave 2 was used for this study. Semantic memory (SM) and Episodic memory (EM) were the main study outcomes separately. The study employed Nested Ordinary Least Square regression analysis by sequentially adding 6 blocks of variables and comparison tests between the nested models.

Results

The study involved 3575 adult Ghanaians aged 50 years and older with a mean ± standard deviation of 62.6 ± 18.4 years. The overall mean ± SD of EM and SM were 5.86 ± 2.51 and 11.69 ± 8.59 respectively. Overall, analysis from block 6 showed a significant variation in SM by approximately 16.9%(ΔR2 = 1.17%) where increasing age, never married (β = -1.55; 95% CI = -2.41-0.69), being resident in Greater Accra (regional disparity) (β = -3.45; 95% CI = -4.73-2.20), underweight (β = -0.81;95% CI = -1.34-0.27), and moderate self-rated health (SRH) (β = -0.98; 95% CI = -1.52-0.45) significantly decreased SM. Similarly, increasing age, separated/divorced (β = -0.22; 95% CI = -0.35-0.87), being resident in Greater Accra (β = -0.53; 95% CI = -0.80-0.26), and moderate SRH (β = -0.20; 95% CI = -0.36--0.04) significantly decrease EM with an overall significant variation of approximately 22.9%(ΔR2 = 2.7%).

Conclusions

Increasing age, sex, marital status, regional disparity, and poor SRH significantly decreased both Semantic memory and Episodic memory. Higher educational attainment and life satisfaction significantly influenced SM and EM. These provide pointers to important socio-demographic determinants of SM and EM with implications for the implementation of the Ghana national ageing policy 2010, 'ageing with security and dignity', and as a key consideration for healthy ageing towards 2030.

Feasibility of an online consensus approach for the diagnosis of cognitive impairment and dementia in rural South Africa

INTRODUCTION

We describe the development and feasibility of using an online consensus approach for diagnosing cognitive impairment and dementia in rural South Africa.

METHODS

Cognitive assessments, clinical evaluations, and informant interviews from Cognition and Dementia in the Health and Aging in Africa Longitudinal Study (HAALSI Dementia) were reviewed by an expert panel using a web-based platform to assign a diagnosis of cognitively normal, mild cognitive impairment (MCI), or dementia.

RESULTS

Six hundred thirty-five participants were assigned a final diagnostic category, with 298 requiring adjudication conference calls. Overall agreement between each rater's independent diagnosis and final diagnosis (via the portal or consensus conference) was 78.3%. A moderate level of agreement between raters' individual ratings and the final diagnostic outcomes was observed (average κ coefficient = 0.50).

DISCUSSION

Findings show initial feasibility in using an online consensus approach for the diagnosis of cognitive impairment and dementia in remote, rural, and low-resource settings.

Comparison of Cognitive and Physical Decline as Predictors of Depression Among Older Adults

Activities of daily living (ADL) limitations and cognitive impairment have been identified as key risk factors for depression among older adults. However, little has been done to compare the strength of these relationships. The current study describes the prevalence and compares the independent and joint associations of ADL and cognitive limitations with depression among older adults in the US. Analyses are based on a sample of 30,923 observations on 13,545 unique respondents from three waves (2012, 2014, and 2016) of the Health and Retirement Study. Linear and logistic multivariate regression models with random and individual fixed effects were estimated. Findings indicate that both cognitive and ADL limitations are associated with depression; however, across all models, ADL limitations have a much stronger association. Further, in our most rigorous models, having both limitations is not significantly different from having just ADL, and not cognitive, limitations.

Prevalence and health outcomes in community-dwelling older adults with comorbid cancer and dementia: a longitudinal analysis

OBJECTIVES

To examine health outcomes in community-dwelling older adults with: dementia only, cancer only, and comorbid cancer and dementia.

METHODS

Longitudinal analysis was conducted using data from 2010 to 2016 waves of the Health and Retirement Study. Health outcomes included mortality, limitations in activities of daily living (ADL) and instrumental activities of daily living (IADL), nursing home utilization, hospital stay, homecare use, self-rated health, and out-of-pocket medical expenditure. Panel regression was used for statistical analysis.

RESULTS

The prevalence of comorbid cancer and dementia ranged from 2.56% to 2.97%. Individuals with comorbid cancer and dementia demonstrated a higher likelihood of nursing home utilization and poorer self-rated health but a lower likelihood of hospital stay, homecare use, and out-of-pocket expenditures, compared to the cancer only or dementia only groups. The differences in mortality and ADL and IADL limitations were not statistically significant.

CONCLUSION

Comorbid cancer and dementia predicted longer nursing home utilization and poorer self-rated health. The results help guide care planning for individuals with comorbid cancer and dementia.

Evaluating the task effectiveness and user satisfaction with different operation modes of an assistive bathing robot in older adults

Bathing robots have the potential to foster the independence of older adults who require assistance with bathing. Making human-robot interaction (HRI) for older persons as easy, effective, and user-satisfying as possible is, however, a major challenge in the development of such robots. The study aimed to evaluate the effectiveness (coverage, step effectiveness) and user satisfaction (After-Scenario Questionnaire, ASQ) with three operation modes (autonomous operation, shared control, tele-manipulation) for the HRI with a bathing robot in potential users. Twenty-five older adults who require bathing assistance tested these operation modes in a water rinsing task for the upper back. Autonomous operation led to maximum effectiveness (100%), which was significantly worse in the shared control (51.6-79.4%, p ≤ 0.001) and tele-manipulation mode (43.9-64.4%, p < .001). In the user-controlled modes, effectiveness decreased with decreasing robot assistance (shared control: 51.6-79.4% vs. tele-manipulation: 43.9-64.4%, p = 0.009-0.016). User satisfaction with the autonomous operation (ASQ: 2.0 ± 1.0pt.) was higher than with the tele-manipulation mode (ASQ: 3.0 ± 1.4pt., p = 0.003) and in trend also than with the shared control mode (ASQ: 2.5 ± 1.5pt., p = 0.071). Our study suggests that for an effective and highly satisfying HRI with a bathing robot in older users, operation modes with high robot autonomy requiring a minimum of user input seem to be necessary.

Cross-Sectional and Longitudinal Associations Between Plasma Neurodegenerative Biomarkers and Physical Performance Among Community-Dwelling Older Adults

BACKGROUND

Plasma amyloid-beta (Aβ), neurofilament light chain (NfL), and progranulin (PGRN) have been related to multiple neurodegenerative conditions that might affect physical performance. The aim of this study was to explore the relationship between these plasma neurodegenerative markers and physical performance among community-dwelling older adults.

METHODS

Five hundred and seven older adults (aged 76 ± 5 years) previously recruited in the Multidomain Alzheimer's Preventive Trial, and had received blood and physical performance tests, were included in this study. Plasma Aβ (Aβ 42/Aβ 40 ratio), NfL, and PGRN levels were measured. Physical performance was assessed by handgrip strength and the Short Physical Performance Battery (combining gait speed, chair stands, and balance tests). Physical performance measured at the same time point and after the blood tests were used. Mixed-effect linear models were performed with age, sex, allocation to Multidomain Alzheimer's Preventive Trial group, body mass index, and Mini-Mental State Examination score as covariates.

RESULTS

The mean values of Aβ 42/Aβ 40 ratio, NfL, and PGRN were 0.11, 84.06 pg/mL, and 45.43 ng/mL, respectively. At the cross-sectional level, higher plasma NfL was associated with a lower Short Physical Performance Battery score (β = -0.004, 95% CI [-0.007, -0.001]). At the longitudinal level, higher PGRN levels were associated with decreasing handgrip strength over time (β = -0.02, 95% CI [-0.04, -0.007]). All the other associations were statistically nonsignificant.

CONCLUSION

Our findings suggest the possibility of using plasma NfL and PGRN as markers of physical performance in older adults.

Racial and ethnic disparities in subjective cognitive decline: a closer look, United States, 2015-2018

BACKGROUND

Subjective cognitive decline (SCD), characterized by self-experience of deterioration in cognitive performance may be a precursor to Alzheimer's disease (AD). Given the association of AD with dependence and disability for a long duration, earlier the detection, the sooner people and their families can receive information regarding better management. It is critical to explore disparities amongst racial and ethnic populations with SCD in order to facilitate targeted interventions. The primary objective was to identify disparities in prevalence of SCD amongst Whites, Blacks and Hispanics by select sociodemographic characteristics and functional limitations in a U.S. population-based sample of non-institutionalized adults aged 45 and older. The secondary objective was to assess the association between SCD and select chronic conditions (angina, heart attack, stroke, diabetes, high blood pressure and high cholesterol) by race/ethnicity.

METHODS

Combined data (2015-2018) were obtained from the Behavioral Risk Factor Surveillance System (BRFSS) to conduct a population -based study. Analyses included 179,852 respondents aged 45 years or older who answered the SCD screening question as "yes" (n = 19,276) or "no" (n = 160,576). Descriptive statistics examined sociodemographic characteristics including functional limitations amongst racial/ethnic groups with SCD. Association of SCD with chronic conditions by race/ethnicity was also calculated.

RESULTS

Overall, 10.8% (CI: 10.6-11.1) of adults aged 45 years or older reported SCD.10.7% Whites, 12.3% Blacks and 9.9% Hispanics experienced SCD. Blacks and Hispanics with SCD were more likely to be in the younger age group (45-54 years), less educated, low income, without access to health care, living alone and with functional limitations. Only half had discussed cognitive decline with a health care professional. Prevalence of selected chronic conditions was significantly higher in all racial/ethnic groups with SCD.

CONCLUSIONS

Demographic trends predict a larger proportion of Hispanics and Blacks with SCD in the coming years. This information can lead to identification of opportunities for addressing negative SCD outcomes in minorities affected by inequitable conditions.

Benefits of pulmonary rehabilitation in COPD patients with mild cognitive impairment - A pilot study

BACKGROUND

Cognitive impairment might interfere with the efficacy of Pulmonary Rehabilitation (PR) in Chronic Obstructive Pulmonary Disease (COPD). We aimed to identify differential responses to PR between cognitively impaired (CI) and cognitively normal (CN) COPD patients by assessing health status and exercise capacity.

METHODS

Sixty patients (FEV₁: 47 ± 15%) were classified as CI or CN according to the Montreal Cognitive Assessment (MoCA ≤25points) and completed a 3-week inpatient PR program. Cognitive function (neuropsychological battery), health-status (36-Item Short Form Survey [SF-36]), and exercise capacity (6-min walk test [6MWT], cycle-endurance test [CET]) were assessed before and after PR. Responsiveness to PR was estimated by mean change (delta-value [Δ]) and the d-Effect Size (ES).

RESULTS

Twenty-five COPD patients (42%) presented evidence of mild CI prior to PR. Both, CI and CN patients significantly improved global cognitive function, health status (the majority of SF-36 components), and exercise capacity (6MWT and cycle endurance) in response to PR. Compared to CN, CI patients did not improve SF-36 subdomains of "role emotional" and "bodily pain", and demonstrated a lower magnitude of improvement in 6MWT ([Δ]: 25 m; ES: 0.21) compared to CN ([Δ]: 46 m; ES: 0.54).

CONCLUSIONS

PR has favorable effects on global cognitive function, health status, and exercise capacity in both CI and CN COPD patients. There was no concrete evidence to indicate interference of cognitive impairment to PR effectiveness.

Plasma Aβ and neurofilament light chain are associated with cognitive and physical function decline in non-dementia older adults

BACKGROUND

Cognition is closely associated with physical function. Although high brain amyloid-β (Aβ) deposition and neurofilament light chain (NfL) are associated with cognitive and gait speed decline, relationships of combined plasma Aβ and NfL profiles with cognitive and physical functions in older adults remain unknown. The research aim of this study was to investigate the prospective associations of combined plasma Aβ and NfL profiles with cognitive and physical functions in older adults.

METHODS

Participants (n = 452, aged 76 ± 5 years) who had both plasma Aβ and NfL data collected from the Multidomain Alzheimer's Preventive Trial (MAPT, May 2008 to April 2016) were included in the current study. These participants were from four MAPT groups (multidomain interventions [physical activity and nutritional counselling, and cognitive training], omega-3 supplementation, multidomain plus omega-3 supplementation and control group) and had received a 3-year intervention, followed by a 2-year observational follow-up. Cognitive function was evaluated as Mini-Mental State Examination and composite cognitive score (CCS, a mean Z-score combining four cognitive tests). Physical function was evaluated as gait speed (4-m usual-pace walk test) and chair-stand time (5-time maximal chair-stand test). Cognitive and physical function data measured at the time of and after blood Aβ and NfL tests were used for analysis. Participants with plasma Aβ42/Aβ40 ratios lower than 0.107 and NfL levels greater than 93.04 pg/ml were classified as Aβ+ and NfL+. Multivariable regressions and mixed-effects linear models were used for the analysis.

RESULTS

At the cross-sectional level, no significant association was found between Aβ+NfL+ and cognitive or physical function after controlling for age, sex, body mass index, education level and MAPT group. Evaluating longitudinal changes, participants with Aβ+NfL+ had greater annual declines in the CCS (β = - 0.11, 95%CI [- 0.17, - 0.05]) and gait speed (β = - 0.03, 95%CI [- 0.05, - 0.005]). After adjusting for APOE ɛ4 genotype, Aβ+NfL+ was associated with a greater decline only in the CCS (β = - 0.09, 95%CI [- 0.15, - 0.02]).

CONCLUSIONS

Combined low plasma Aβ42/Aβ40 ratio and high plasma NfL level was associated with greater declines in cognition and gait speed over time, providing further evidence of the links between cognitive and physical function.

TRIAL REGISTRATION

www.clinicaltrials.gov [ NCT00672685 ].

The power of the Functional Activities Questionnaire for screening dementia in rural-dwelling older adults at high-risk of cognitive impairment

AIM

A simple approach to detecting dementia in its early stages may help improve patient care. We therefore aimed to assess the power of the Functional Activities Questionnaire (FAQ) for screening dementia among rural-dwelling older adults who are at high-risk for cognitive impairment.

METHODS

This study included 961 participants at a high-risk for dementia who had been identified from a population-based survey of Chinese rural residents. All participants were aged 65 years and older and positive for cognitive impairment according to the Mini-Mental State Examination or the Ascertain Dementia 8-item Informant Questionnaire screening tests. The FAQ scale was used to evaluate daily activities. Dementia was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, criteria. Receiver operating characteristic curve analyses were used to determine the FAQ's optimal cut-offs for dementia. The power (or accuracy) of the FAQ for screening dementia was analyzed in the total sample and in subgroups categorized by age, gender, and educational level.

RESULTS

Of the 961 participants, 84 (8.7%) were clinically diagnosed with dementia. Among individuals who were positive for cognitive impairment on the Mini-Mental State Examination or the Ascertain Dementia 8-item Informant Questionnaire, the parameters for an FAQ cut-off score ≥6 as a means of discriminating those with dementia from those without dementia were area under curve = 0.899, sensitivity = 94.1%, specificity = 75.1%, positive likelihood ratio = 3.78, and accuracy = 0.768. The discriminant abilities of the FAQ scale varied with age, gender, and educational level. The discriminant parameters of the FAQ scale were similar overall among individuals who were positive on either the Mini-Mental State Examination or the Ascertain Dementia 8-item Informant Questionnaire test alone.

CONCLUSION

The FAQ scale has high discriminative power to screen for dementia among rural older residents with suspected cognitive impairment.

Predicting Functional Dependence in Mild Cognitive Impairment: Differential Contributions of Memory and Executive Functions

BACKGROUND AND OBJECTIVES

Diagnostic criteria for mild cognitive impairment (MCI) exclude functional deficits, yet recent studies suggest that older adults with MCI can exhibit impairment in instrumental activities of daily living (IADL). To assist health care providers in detecting functional vulnerabilities that often precipitate loss of independence, we: (a) compared IADL dependence in MCI to older adults without cognitive impairment and those with dementia, (b) estimated the odds of dependence on specific IADLs in MCI, and (c) investigated the differential contributions of memory and executive functions to IADL dependence.

RESEARCH DESIGN AND METHODS

Participants were older adults (Mage = 77.58 ± 11.05) in Maryland, USA (N = 512) community and postacute rehabilitation settings. Analysis was performed on Brief Cognitive Assessment Tool (BCAT) and the Functional Activities Questionnaire (FAQ) data that assessed participants' cognitive functioning and IADL dependence, respectively.

RESULTS

61.04% of participants with MCI were dependent on one or more IADLs. MCI was associated with significantly greater odds of dependence than normal cognition on 7 of the 10 IADLs (odds ratios = 2.62-4.66). Impairment in memory and executive functions significantly predicted IADL dependence (18.52% of variance beyond demographics); executive functions were the stronger predictor, particularly for complex finances, complex cooking, and remembering events.

DISCUSSION AND IMPLICATIONS

IADL dependence can occur even in MCI. Testing suggestive of MCI should alert clinicians to further investigate the older adult's profile of cognitive and functional limitations to highlight targets for caregiver support and promote independence by "right-sizing" community or facility resources.

Brain amyloid, cortical thickness, and changes in activities of daily living

OBJECTIVE

To examine the association of baseline elevated brain amyloid and neurodegeneration with changes in activities of daily living in participants without dementia (ND; i.e., cognitively unimpaired and participants with mild cognitive impairment) at baseline in the population-based Mayo Clinic Study of Aging.

METHODS

We included 1747 ND participants with 11 C-PiB PET and MR imaging in the study, with data on activities of daily living (as assessed by the Functional Activities Questionnaire (FAQ) and the Clinical Dementia Rating scale Sum of Boxes for functional domains (CDR-SOB (functional)), with a median (range) of 4.3 (0.0-12.7) years of follow-up. Abnormal (elevated; A+) 11 C-PiB-PET retention ratio was defined as standardized uptake value ratio ≥ 1.48, and abnormal (reduced) AD signature cortical thickness as ≤ 2.68 mm (neurodegeneration; N+). Associations were examined with mixed effects models, adjusting for age, sex, education, apolipoprotein E ε4 allele carrier status, and global cognitive z-score.

RESULTS

Mean age (SD) was 71.4 years (10.1), 46.7% were females, 195 (11.2%) had A+N-, 442 (25.3%) had A-N+, and 339 (19.4%) had A+N+ biomarkers. The A+N+ group had the largest annualized change in the FAQ score from baseline (difference in annual change A+N+ vs. A-N-; ß (SE): 0.80 (0.07)); associations were substantially attenuated when a time-varying global cognitive composite was included in the model (A+N+ vs. A-N-; ß (SE): 0.31 (0.05)). CDR-SOB (functional) findings partly agreed with FAQ score findings.

INTERPRETATION

The longitudinal increase in functional limitations is greater for individuals with abnormal neuroimaging biomarkers, especially for those with both elevated brain amyloid and neurodegeneration.

Improving gesture-based interaction between an assistive bathing robot and older adults via user training on the gestural commands

BACKGROUND

Gesture-based human-robot interaction (HRI) depends on the technical performance of the robot-integrated gesture recognition system (GRS) and on the gestural performance of the robot user, which has been shown to be rather low in older adults. Training of gestural commands (GCs) might improve the quality of older users' input for gesture-based HRI, which in turn may lead to an overall improved HRI.

OBJECTIVE

To evaluate the effects of a user training on gesture-based HRI between an assistive bathing robot and potential elderly robot users.

METHODS

Twenty-five older adults with bathing disability participated in this quasi-experimental, single-group, pre-/post-test study and underwent a specific user training (10-15 min) on GCs for HRI with the assistive bathing robot. Outcomes measured before and after training included participants' gestural performance assessed by a scoring method of an established test of gesture production (TULIA) and sensor-based gestural performance (SGP) scores derived from the GRS-recorded data, and robot's command recognition rate (CRR).

RESULTS

Gestural performance (TULIA = +57.1 ± 56.2 %, SGP scores = +41.1 ± 74.4 %) and CRR (+31.9 ± 51.2 %) significantly improved over training (p < .001). Improvements in gestural performance and CRR were highly associated with each other (r = 0.80-0.81, p < .001). Participants with lower initial gestural performance and higher gerontechnology anxiety benefited most from the training.

CONCLUSIONS

Our study highlights that training in gesture-based HRI with an assistive bathing robot is highly beneficial for the quality of older users' GCs, leading to higher CRRs of the robot-integrated GRS, and thus to an overall improved HRI.

Pre-Intensive Care Unit Cognitive Status, Subsequent Disability, and New Nursing Home Admission among Critically Ill Older Adults

RATIONALE

Cognitive impairment is common among older adults, yet little is known about the association of pre-intensive care unit cognitive status with outcomes relevant to older adults maintaining independence after a critical illness.

OBJECTIVES

To evaluate whether pre-intensive care unit cognitive status is associated with post-intensive care unit disability, new nursing home admission, and mortality after a critical illness among older adults.

METHODS

In this prospective cohort study, 754 persons aged 70 years or more were monitored from March 1998 to December 2013 with monthly assessments of disability. Cognitive status was assessed every 18 months, using the Mini-Mental State Examination (range, 0-30), with scores classified as 28 or higher (cognitively intact), 24-27 (minimal impairment), and less than 24 (moderate impairment). The primary outcome was disability count (range, 0-13), assessed monthly over 6 months after an intensive care unit stay. The secondary outcomes were incident nursing home admission and time to death after intensive care unit admission. The analytic sample included 391 intensive care unit admissions.

RESULTS

The mean age was 83.5 years. The prevalence of moderate impairment, minimal impairment, and intact cognition (the comparison group) was 17.3, 46.2, and 36.5%, respectively. In the multivariable analysis, moderate impairment was associated with nearly a 20% increase in disability over the 6-month follow-up period (adjusted relative risk, 1.19; 95% confidence interval, 1.04-1.36), and minimal impairment was associated with a 16% increase in post-intensive care unit disability (adjusted relative risk, 1.16; 95% confidence interval, 1.02-1.32). Moderate impairment was associated with more than double the likelihood of a new nursing home admission (adjusted odds ratio, 2.37; 95% confidence interval, 1.01-5.55). Survival differed significantly across the three cognitive groups (log-rank P = 0.002), but neither moderate impairment (adjusted hazard ratio, 1.19; 95% confidence interval, 0.65-2.19) nor minimal impairment (adjusted hazard ratio, 1.00; 95% confidence interval, 0.61-1.62) was significantly associated with mortality in the multivariable analysis.

CONCLUSIONS

Among older adults, any impairment (even minimal) in pre-intensive care unit cognitive status was associated with an increase in post-intensive care unit disability over the 6 months after a critical illness; moderate cognitive impairment doubled the likelihood of a new nursing home admission. Pre-intensive care unit cognitive impairment was not associated with mortality from intensive care unit admission through 6 months of follow-up. Pre-intensive care unit cognitive status may provide prognostic information about the likelihood of older adults maintaining independence after a critical illness.

Combined effects of cognitive impairment and pre-frailty on future frailty and death in older Mexican Americans

Objectives: Impaired cognition and pre-frailty are associated with poor health outcomes. However, research has not examined the combined impact of cognitive impairment and pre-frailty on future frailty and mortality among older Mexican Americans. Methods: Data for this analysis came from the 2006-2007 and 2010-2011 waves of the Hispanic EPESE. The final sample included 639 Mexican Americans aged ≥77 years who were non-frail or pre-frail in 2006-2007. Frailty measure included weight loss, exhaustion, weakness, and slow walking speed. Participants were classified as non-frail (0 criteria) and pre-frail (1 criterion) at baseline. Cognitive impairment was defined as <21 points on the MMSE. At baseline, participants were grouped as: cognitively intact non-frail, cognitively intact pre-frail, cognitively impaired non-frail, and cognitively impaired pre-frail. Logistic and hazard regression models were used to evaluate the odds of being frail in 2010-2011 and risk for 10-year mortality. Results: Cognitively impaired pre-frail participants were more likely to become frail (OR = 4.82, 95% CI = 2.02-11.42) and deceased (HR = 1.99, 95% CI = 1.42-2.78). Cognitively impaired non-frail participants had significantly higher risk for mortality (HR = 1.55, 95% CI = 1.12-2.19) but not frailty (OR = 1.29, 95% CI = 0.50-3.11). Being cognitively intact and pre-frail at baseline was not significantly associated with being frail at follow-up (OR = 1.62, 95% CI = 0.83-3.19) or mortality (HR = 1.29, 95% CI = 0.97-1.71). Conclusions: Comorbid cognitive impairment and pre-frailty is associated with future frailty and mortality in older Mexican Americans. Screening for cognitive impairment may be effective for identifying pre-frail Mexican Americans who are at the highest risk of frailty and mortality.

Screening for Functional Cognition in Postacute Care and the Improving Medicare Post-Acute Care Transformation (IMPACT) Act of 2014

Occupational therapists have a long history of assessing functional cognition, defined as the ability to use and integrate thinking and performance skills to accomplish complex everyday activities. In response to passage of the Improving Medicare Post-Acute Care Transformation (IMPACT) Act of 2014 (Pub. L. 113-185), the American Occupational Therapy Association has been advocating that the Centers for Medicare and Medicaid Services consider functional cognition for inclusion in routine patient assessment in postacute care settings, with important implications for occupational therapy. These efforts have the potential to increase referrals to occupational therapy, emphasize the importance of addressing functional cognition in occupational therapy practice, and support the value of occupational therapy in achieving optimal postacute care outcomes.

Early Functional Limitations in Cognitively Normal Older Adults Predict Diagnostic Conversion to Mild Cognitive Impairment

OBJECTIVES

To examine whether specific types of early functional limitations in cognitively normal older adults are associated with subsequent development of mild cognitive impairment (MCI), as well as the relative predictive value of self versus informant report in predicting diagnostic conversion to MCI.

DESIGN

As a part of a longitudinal study design, participants underwent baseline and annual multidisciplinary clinical evaluations, including a physical and neurological examination, imaging, laboratory work, and neuropsychological testing.

SETTING

Data used in this study were collected as part of longitudinal research at the University of California, Davis Alzheimer's Disease Center.

PARTICIPANTS

Individuals diagnosed as having normal cognition at study baseline who had an informant who could complete informant-based ratings and at least one follow-up visit (N = 324).

MEASUREMENTS

Participants and informants each completed the Everyday Cognition Scale (ECog), an instrument designed to measure everyday function in six cognitively relevant domains.

RESULTS

Self- and informant-reported functional limitations on the ECog were associated with significantly greater risk of diagnostic conversion to MCI (informant: hazard ratio (HR) = 2.0, 95% confidence interval (CI) = 1.3-3.2, P = .002), with self-report having a slightly higher hazard (HR = 2.3, 95% CI = 1.4-3.6, P < .001). When controlling for baseline cognitive abilities, the effect remained significant for self- and informant-reported functional limitations.

CONCLUSION

Deficits in everyday memory and executive function domains were the strongest predictors of diagnostic conversion to MCI. Detection of early functional limitations may be clinically useful in assessing the future risk of developing cognitive impairment in cognitively normal older adults.

Functional limitations and health care resource utilization for individuals with cognitive impairment without dementia: Findings from a United States population-based survey

Introduction

Little is known about functional limitations and health care resource utilization of people with cognitive impairment with no dementia (CIND).

Methods

Respondents with stable or progressive cognitive impairment (CI) after the first (index) indication of CIND in 2000–2010 were identified from the Health and Retirement Study (HRS). Respondents never exhibiting CI were identified as potential controls. Propensity score–based optimal matching was used to adjust for differences in demographics and history of stroke. Differences between cohorts were assessed accounting for HRS survey design.

Results

After matching, CIND respondents had more functional limitations (difficulty with ≥1 activities of daily living: 24% vs. 15%; ≥1 instrumental activities of daily living: 20% vs. 11%) and hospital stays (37% vs. 27%) than respondents with no CI (all P < .001). Seventy five percent of CIND respondents developed dementia in the observable follow-up (median time: ∼6 years).

Discussion

Even before dementia onset, CI is associated with increased likelihood of functional limitations and greater health care resource use.

Trajectory of Mobility Decline by Type of Dementia

Cognitive and physical aspects of functionality are closely related. However, whether physical decline differs by dementia type and progression rate is debatable. To address these issues, we conducted a longitudinal study of 766 older adults whose physical performance and cognitive status were assessed annually with standard assessment tools [eg, Physical Performance Test, Clinical Dementia Rate (CDR)] for 8 years. Compared with participants who remained cognitively normal, those progressing to later-stage dementia (CDR=1) declined in their mobility by a factor of 2.82 (P<0.001), followed by those who maintained a later-stage diagnosis (slope=-1.84, P<0.001), those progressing from early-stage to later-stage (CDR=0.5 to CDR=1) dementia (slope=-1.20, P<0.001), and those who progressed to early-stage dementia (slope=-0.39, P=0.038) suggesting a steeper physical decline with dementia progression, particularly in those with the fastest disease progression. Although all types of dementia experienced mobility decline, those progressing to non-Alzheimer disease (AD) dementias, especially vascular dementia declined faster than those who remained normal (slope=-2.70, P<0.001) or progressed to AD (slope=-2.18, P<0.001). These associations were better captured by the gait/balance component of physical functionality. Our findings suggest that rapidly progressing dementia patients particularly those with non-AD subtypes should be targeted for interventions to maintain or improve gait/balance and prevent functional decline and disability although AD patients may also benefit.

Brain Amyloid Deposition Is Associated With Lower Instrumental Activities of Daily Living Abilities in Older Adults. Results From the MAPT Study

BACKGROUND

Brain amyloid deposition is one of the key pathological hallmarks underlying the cognitive changes associated with Alzheimer's disease. Growing interest has been given to the earliest clinical manifestations of amyloid plaques. However, the relationship between amyloid status and activities of everyday function remains largely unknown. In the present study, we examined the relationship between instrumental activities of daily living performance (using the ADL-PI score) and amyloid status in older adults.

METHODS

Cross-sectional analyses of data from the Multidomain Alzheimer Preventive Trial (MAPT) were performed. Volunteers underwent a brain 18F-AV45 positron emission tomography examination. Bivariate analysis and regression models were conducted to study the relationships between brain amyloid deposition and the total ADL-PI score.

RESULTS

We included 271 participants (women = 60%; age = 76±4 years). Amyloid positron emission tomography was positive (standard uptake value ≥1.17) for 103 participants (38%). The ADL-PI score was lower in amyloid positive participants than in their amyloid negative counterparts (38.8 vs 40.3, p = .007). This association was also confirmed in regression models adjusted for age, gender, and familial history of Alzheimer's disease (odds ratio = 0.94; 95% confidence interval 0.89-0.99; p = .02). This finding was consistent in cognitively normal individuals and in those with mild cognitive impairment, using the clinical dementia rating scale.

CONCLUSIONS

This study highlighted an association between early functional limitations and brain amyloid deposition in elderly subjects. These symptoms could be the clinical manifestations of amyloid plaques even in the absence of overt dementia. Further prospective studies are warranted for examining the evolution of ADL-PI score over the course of Alzheimer's disease.

Peripheral Hearing and Cognition: Evidence From the Staying Keen in Later Life (SKILL) Study

OBJECTIVES

Research has increasingly suggested a consistent relationship between peripheral hearing and selected measures of cognition in older adults. However, other studies yield conflicting findings. The primary purpose of the present study was to further elucidate the relationship between peripheral hearing and three domains of cognition and one measure of global cognitive status. It was hypothesized that peripheral hearing loss would be significantly associated with poorer performance across measures of cognition, even after adjusting for documented risk factors. No study to date has examined the relationship between peripheral hearing and such an extensive array of cognitive measures.

DESIGN

Eight hundred ninety-four older adult participants from the Staying Keen in Later Life study cohort were eligible, agreed to participate, and completed the baseline evaluation. Inclusion criteria were minimal to include a sample of older adults with a wide range of sensory and cognitive abilities. Multiple linear regression analyses were conducted to evaluate the extent to which peripheral hearing predicted performance on a global measure of cognitive status, as well as multiple cognitive measures in the domains of speed of processing (Digit Symbol Substitution and Copy, Trail Making Test Part A, Letter and Pattern Comparison, and Useful Field of View), executive function (Trail Making Test Part B and Stroop Color-Word Interference Task), and memory (Digit Span, Spatial Span, and Hopkins Verbal Learning Test).

RESULTS

Peripheral hearing, measured as the three-frequency pure-tone average (PTA) in the better ear, accounted for a significant, but minimal, amount of the variance in measures of speed of processing, executive function, and memory, as well as global cognitive status. Alternative measures of hearing (i.e., three-frequency PTAs in the right and left ears and a bilateral, six-frequency PTA [three frequencies per ear]) yielded similar findings across measures of cognition and did not alter the study outcomes in any meaningful way.

CONCLUSIONS

Consistent with literature suggesting a significant relationship between peripheral hearing and cognition, and in agreement with our hypothesis, peripheral hearing was significantly related to 10 of 11 measures of cognition that assessed processing speed, executive function, or memory, as well as global cognitive status. Although evidence, including the present results, suggests a relationship between peripheral hearing and cognition, little is known about the underlying mechanisms. Examination of these mechanisms is a critical need to direct appropriate treatment.

Longitudinal associations between physical and cognitive performance among community-dwelling older adults

To assess the directionality of the association between physical and cognitive decline in later life, we compared patterns of decline in performance across groups defined by baseline presence of cognitive and/or physical impairment [none (n = 217); physical only (n = 169); cognitive only (n = 158), or both (n = 220)] in a large sample of participants in a cognitive aging study at the Knight Alzheimer's Disease Research Center at Washington University in St. Louis who were followed for up to 8 years (3,079 observations). Rates of decline reached 20% for physical performance and varied across cognitive tests (global, memory, speed, executive function, and visuospatial skills). We found that physical decline was better predicted by baseline cognitive impairment (slope = -1.22, p<0.001), with baseline physical impairment not contributing to further decline in physical performance (slope = -0.25, p = 0.294). In turn, baseline physical impairment was only marginally associated with rate of cognitive decline across various cognitive domains. The cognitive-functional association is likely to operate in the direction of cognitive impairment to physical decline although physical impairment may also play a role in cognitive decline/dementia. Interventions to prevent further functional decline and development of disability and complete dependence may benefit if targeted to individuals with cognitive impairment who are at increased risk.

Preliminary cognitive scale of basic and instrumental activities of daily living for dementia and mild cognitive impairment

In the present study we explored cognitive and functional deficits in patients with multidomain mild cognitive impairment (MCI), patients with dementia, and healthy age-matched control participants using the Cognitive Scale for Basic and Instrumental Activities of Daily Living, a new preliminary informant-based assessment tool. This tool allowed us to evaluate four key cognitive abilities-task memory schema, error detection, problem solving, and task self-initiation-in a range of basic and instrumental activities of daily living (BADL and IADL, respectively). The first part of the present study was devoted to testing the psychometric adequateness of this new informant-based tool and its convergent validity with other global functioning and neuropsychological measures. The second part of the study was aimed at finding the patterns of everyday cognitive factors that best discriminate between the three groups. We found that patients with dementia exhibited impairment in all cognitive abilities in both basic and instrumental activities. By contrast, patients with MCI were found to have preserved task memory schema in both types of ADL; however, such patients exhibited deficits in error detection and task self-initiation but only in IADL. Finally, patients with MCI also showed a generalized problem solving deficit that affected even BADL. Studying various cognitive processes instantiated in specific ADL differing in complexity seems a promising strategy to further understand the specific relationships between cognition and function in these and other cognitively impaired populations.

Oestradiol modulation of cognition in adult female marmosets (Callithrix jacchus)

The common marmoset (Callithrix jacchus) provides many advantages over traditional rodent and macaque species as a model for human ageing and may be very useful for studying the effects of sex steroids on cognitive and brain ageing. We present the first study examining the effects of oestrogens on cognitive function in female marmosets. Adult monkeys (3-5 years of age) were trained to a specific learning criterion on a battery of cognitive tasks preoperatively (object discrimination, delayed response with increasing delays and detour reaching with opaque box) and were tested on different versions of these tasks (object reversals, delayed response with randomised delays and detour reaching with clear box) after ovariectomy and simultaneous implantation with 17β-oestradiol (E2 ) (n = 6) or blank (n = 6) Silastic capsules. Acquisition of a delayed matching-to-position task with a 1-s delay was also administered after completion of these tests. E2 -treated monkeys were significantly impaired on the second reversal and showed an increase in perseverative responding from reversals 1-3. Their performance also tended to be worse than that of control monkeys on the delayed response task. Performance acquisition on the delayed matching-to-position tended to be better in E2 -treated relative to control monkeys, although the group difference did not reach statistical significance. No effect of treatment was detected for detour reaching or affiliative behaviours. Overall, the findings indicate that E2 compromises performance on prefrontally-mediated tasks. The suggestion that E2 may improve acquisition on tasks dependent on the hippocampus will require further validation. These results are discussed in the context of dopaminergic and serotonergic signalling. We conclude that the marmoset is a useful new primate model for examining the effects of oestrogens on cognitive function.

Funções executivas, atividades da vida diária e habilidade motora de idosos com doenças neurodegenerativas

Objetivo: Analisar as funções executivas de idosos com doença de Parkinson (DP – com e sem quadro demencial) e doença de Alzheimer (DA), e confrontar os escores dos participantes no que se refere às atividades funcionais da vida diária e à habilidade motora em situações de dupla tarefa. Métodos: Sob um desenho transversal, 54 idosos foram divididos em quatro grupos: G1, composto por 11 sujeitos com DP; G2, formado por 10 sujeitos com demência de Parkinson; G3, composto por 13 participantes com DA; e G4, formado por 20 idosos saudáveis. Os procedimentos metodológicos envolveram análise das funções cognitivas pré-frontais dos sujeitos, da realização das atividades da vida diária e da habilidade motora em situações de dupla tarefa. A análise dos dados envolveu a estatística descritiva (média e erro-padrão) e inferencial (teste ANOVA e pós-teste de Scheffé), admitindo significância de 5% (p < 0,05) e intervalo de confiança de 95%. Resultados: As funções cognitivas pré-frontais apresentaram diferença significativa entre os grupos, sobretudo nas comparações envolvendo G2 e G3, em relação a G1 e G4 (p = 0,001). Os grupos com déficit cognitivo apresentaram pior rendimento na realização das atividades da vida diária, com menor escore do G2, na qual há junção de déficit cognitivo e motor (p = 0,001). Em situações de dupla tarefa, G2 e G3 apresentaram maiores dificuldades que os demais grupos (p < 0,05). Conclusão: Distúrbios pré-frontais repercutem negativamente nas atividades funcionais e na habilidade psicomotora dos indivíduos. Quando não vinculado a quadro demencial, os pacientes com DP apresentaram escores cognitivos pré-frontais e independência funcional semelhantes aos de idosos saudáveis.