Cognitive Function In Older Individuals Research Articles

Association between geriatric nutritional risk index and cognitive function in older adults with/without chronic kidney disease.

Cognitive impairment is highly prevalent among patients with chronic kidney disease, who face an increased risk of cognitive decline. The aim of this study was to investigate the relationship between the Geriatric Nutritional Risk Index (GNRI) and cognitive function in older individuals, both with and without chronic kidney disease (CKD). In this study, we analyzed data from 2728 participants in the 2011-2014 National Health and Nutrition Examination Survey (NHANES). Cognitive function was measured using the Consortium to Establish a Registry for the Alzheimer's Disease Word Learning subtest (CERAD W-L), the animal fluency test (AFT), the digit symbol substitution test (DSST), and the global cognitive z-score. The GNRI, representing whole-body nutritional status, was calculated based on serum albumin, body weight, and ideal body weight. We employed weighted multiple linear regression analyses and subgroup analyses to assess the independent association of GNRI with cognitive function in CKD and non-CKD populations. Smoothing techniques were used to fit curves, and interaction tests were used to assess the robustness and specificity of the findings. Our analyses revealed a significant positive association between higher GNRI levels and cognitive function in the older US population (for global z-score: β=0.01; 95% confidence interval [CI]=0.00, 0.01). This association remained consistent across various subgroup analyses, including those for different gender groups, age groups, smoking statuses, diabetes statuses, hypertension statuses, individuals with a BMI below 25, individuals who consumed alcohol, and non-Hispanic white individuals. Smoothed curve-fitting analyses indicated that the GNRI was linearly related to cognitive function. No statistically significant interactions were detected among these variables. Our findings emphasize the positive association between GNRI and cognitive health in individuals with or without CKD, especially when combined with other risk factors. Consequently, enhancing the nutritional status of the elderly may serve as a viable strategy to thwart the onset of cognitive decline.

Application of a new definition of sarcopenic obesity in middle-aged and older adults and association with cognitive function: Findings from the National Health and Nutrition Examination Survey 1999–2002

Background & aimsThe role of sarcopenic obesity (SO) in impaired cognitive function has been investigated in several observational studies, but results have been mixed. This study applied the proposed European Society for Clinical Nutrition and Metabolism (ESPEN)-European Association for the Study of Obesity (EASO) definition of SO to a representative population aged ≥50 years to identify the association between SO and cognitive function. MethodsData from the National Health and Nutrition Examination Survey 1999-2002 waves were used. At the screening phase, body mass index or waist circumference were used to evaluate obesity; sarcopenia was identified using the SARC-F questionnaire. At the diagnostic phase I and II, sarcopenia was assessed using knee extensor isometric strength and appendicular lean mass, and fat mass percent was used to assess obesity. Cognitive function in older participants (60-85 years) was assessed using the Digit Symbol Substitution Test. A self-reported memory question was used in middle-aged individuals (50-59 years). ResultsThe sample included 2,356 participants (men, 44.7%). The prevalence of SO was 32.3%, 21.2% and 15.0% at the screening, diagnosis phase I, and diagnosis phase II, respectively. Significant associations between SO and cognitive impairment were observed in individuals aged 60-85 at diagnosis phase I (OR: 2.3, 95%CI 1.4-3.8, P=0.007) and phase II (OR: 2.7, 95%CI 1.5-4.9, P=0.004). ConclusionThe new ESPEN-EASO definition of SO identified a high prevalence of SO cases. A significant association between SO and poor cognitive function in older individuals was observed.

An unexpected interaction between diabetes and cardiovascular diseases on cognitive function: A cross-sectional study

ObjectiveImpaired cognitive function in older individuals significantly affects quality of life. The interaction between comorbid diabetes and cardiovascular disease (CVD) and its impact on cognitive impairment remains unclear. MethodsThis study analyzed 2564 subjects from the National Health and Nutrition Examination Survey dataset. Cognitive function was measured using various scores, including CERAD Total Score, CERAD Delayed Recall Score (CDRS), Animal Fluency Total Score, and Digit Symbol Score. Multiple regression models were constructed to explore the relationship between different diseases and cognitive function, considering covariates such as age, sex, education, body mass index, alcohol intake, smoking, physical activity, kidney function, and hypertension. ResultsAfter adjusting for multiple factors, the presence of CVD, diabetes, or both showed a significant negative association with the total cognitive score. The CDRS was associated with both CVD and diabetes. The Digit Symbol score was associated with the presence of CVD, diabetes, or both. No significant differences were found between patients with diabetes and CVD in cognitive test results. An interaction between CVD and diabetes was observed in relation to the CDRS but not in other test scores or the total score. ConclusionThe individual impact of each disease on cognitive function was not significant. However, an interaction between CVD and diabetes was found when both diseases coexisted, specifically in relation to delayed learning ability.

Associations of Balance, Strength, and Gait Speed with Cognitive Function in Older Individuals over 60 Years: A Cross-Sectional Study

This research examined the association between the risk of falls and cognitive function in older individuals at risk of mild cognitive impairment. One hundred seventy-five older adults were included in 2021. Balance confidence was scored using the Activities-Specific Balance Confidence Scale (ABC), gait speed was assessed by the 4 m test, handgrip strength by a digital dynamometer, and balance by the Timed Up-and-Go Test (TUG). The Mini-Mental State Examination (MMSE), The Controlled Oral Word Association Test, and The Boston Naming Test short-version questionnaires assessed global cognitive function, verbal fluency, and language, respectively. A bivariate correlation analysis and multivariate linear regressions were applied, adjusting for confounders (BMI, sex, age, and educational level). Shorter time in the TUG and greater educational status were independently associated with improved scores on the MMSE. Lower age and greater educational status were independently associated with increased phonological fluency. Better ABC and performance on the TUG and higher educational attainment were independently associated with enhanced semantic fluency. Higher education level and gait speed were independently associated with increased language (all p < 0.05). Improved physical factors, such as gait speed, grip strength, balance, and balance confidence enhanced cognitive function, particularly global cognitive function, verbal fluency, and language, in individuals over 60, with education as a potential confounder.

HEMOPEXIN’S RELATIONSHIP WITH MUSCLE QUALITY AND COGNITIVE FUNCTION IN OLDER ADULTS WITH COGNITIVE IMPAIRMENT

Abstract The imminent increase in Alzheimer’s disease (AD) and dementia increases the need for effective prevention strategies. Increasig attention has been paid to exercise as a prevention strateg to promote cognitive health. Recently, the link between hemopexin which is secreted by atrophied skeletal muscle and cognitive function maintenance has been studied, but evidence remains inconclusive.This study examined the relationship between hemopexin, muscle mass, muscle quality (Phase Angle, PhA), and cognitive function (measured by Mini-Mental State Examination) among 377 cognitively impaired older adults (mean age = 83.5 years).TANITA (MC-780A-N) was used to measure body composition. The concentration of hemopexin in human plasma samples was measured using the HPX (Human) ELISA Kit (KA0481). In Pearson correlation analysis, hemopexin showed no significant correlation with muscle mass, quality, or cognitive function. Multivariate regression analysis revealed that lower PhA is significantly associated with poorer cognitive function (t-value=2.012, p< 0.05), but hemopexin and muscle mass were not significant. An interaction analysis indicated that the relationship between hemopexin and muscle quality was modified by sex (t-value=2.052, p< 0.05). In the multivariate analysis for females, hemopexin correlated negatively with muscle quality (t-value=-2.128, p< 0.05). This study shows that hemopexin, though not affecting cognitive function or muscle mass directly, may impact muscle quality, especially considering the link between AD in older women and atrophied muscle with hemopexin secretion. Hence, interventions focused on muscle quality might improve cognitive function in older individuals with cognitive impairment, possibly preventing dementia onset. Further studies are warranted to solidify these connections.

Quantitative estimate of cognitive resilience and its medical and genetic associations

BackgroundWe have proposed that cognitive resilience (CR) counteracts brain damage from Alzheimer’s disease (AD) or AD-related dementias such that older individuals who harbor neurodegenerative disease burden sufficient to cause dementia remain cognitively normal. However, CR traditionally is considered a binary trait, capturing only the most extreme examples, and is often inconsistently defined.MethodsThis study addressed existing discrepancies and shortcomings of the current CR definition by proposing a framework for defining CR as a continuous variable for each neuropsychological test. The linear equations clarified CR’s relationship to closely related terms, including cognitive function, reserve, compensation, and damage. Primarily, resilience is defined as a function of cognitive performance and damage from neuropathologic damage. As such, the study utilized data from 844 individuals (age = 79 ± 12, 44% female) in the National Alzheimer’s Coordinating Center cohort that met our inclusion criteria of comprehensive lesion rankings for 17 neuropathologic features and complete neuropsychological test results. Machine learning models and GWAS then were used to identify medical and genetic factors that are associated with CR.ResultsCR varied across five cognitive assessments and was greater in female participants, associated with longer survival, and weakly associated with educational attainment or APOE ε4 allele. In contrast, damage was strongly associated with APOE ε4 allele (P value < 0.0001). Major predictors of CR were cardiovascular health and social interactions, as well as the absence of behavioral symptoms.ConclusionsOur framework explicitly decoupled the effects of CR from neuropathologic damage. Characterizations and genetic association study of these two components suggest that the underlying CR mechanism has minimal overlap with the disease mechanism. Moreover, the identified medical features associated with CR suggest modifiable features to counteract clinical expression of damage and maintain cognitive function in older individuals.

Serum transthyretin level and its relationship with cognitive function in community-dwelling older people: Cross sectional and longitudinal study

BackgroundSerum transthyretin (TTR) level has suggested association with mild cognitive impairment (MCI) and dementia. To clarify its usefulness as a biomarker of change in cognitive function in older individuals with normal cognitive function (NC) as a phenotype, we investigated the relationship between cognitive scores and TTR levels. We also investigated the involvement of TTR in the transition from NC to MCI. MethodsCognitive function was evaluated using Addenbrooke's Cognitive Examination-Revised (ACE-R). A cross-sectional study was conducted in community-dwelling older people (n = 211) with NC, MCI, or dementia according to ACE-R scores. A 32-month longitudinal study was then conducted (n = 29). ResultsMean TTR levels did not differ between the NC, MCI and dementia groups. Linear regression analysis showed a significant relationship in people with NC between TTR and ACE-R (β = -0.192; p < 0.001). Multiple regression analysis adjusted for stepwise procedure-selected covariates showed that TTR was significantly associated with ACE-R in people with NC (β = -0.130; p = 0.014). Furthermore, multiple regression analysis showed significant association between TTR level and memory (β = -0.584; p = 0.002) and with language (β = -0.743; p = 0.031) in people with NC. In the longitudinal study, mean TTR level at baseline in women with MCI was significantly higher than that in women with NC (p = 0.044). ConclusionsSerum TTR level is suggested to be associated with cognitive scores in people with NC and to be an indicator of progression from NC to MCI.

Hub structure in functional network of EEG signals supporting high cognitive functions in older individuals.

Maintaining high cognitive functions is desirable for "wellbeing" in old age and is particularly relevant to a super-aging society. According to their individual cognitive functions, optimal intervention for older individuals facilitates the maintenance of cognitive functions. Cognitive function is a result of whole-brain interactions. These interactions are reflected in several measures in graph theory analysis for the topological characteristics of functional connectivity. Betweenness centrality (BC), which can identify the "hub" node, i.e., the most important node affecting whole-brain network activity, may be appropriate for capturing whole-brain interactions. During the past decade, BC has been applied to capture changes in brain networks related to cognitive deficits arising from pathological conditions. In this study, we hypothesized that the hub structure of functional networks would reflect cognitive function, even in healthy elderly individuals. To test this hypothesis, based on the BC value of the functional connectivity obtained using the phase lag index from the electroencephalogram under the eyes closed resting state, we examined the relationship between the BC value and cognitive function measured using the Five Cognitive Functions test total score. We found a significant positive correlation of BC with cognitive functioning and a significant enhancement in the BC value of individuals with high cognitive functioning, particularly in the frontal theta network. The hub structure may reflect the sophisticated integration and transmission of information in whole-brain networks to support high-level cognitive function. Our findings may contribute to the development of biomarkers for assessing cognitive function, enabling optimal interventions for maintaining cognitive function in older individuals.

The effects of aerobic exercise and transcranial direct current stimulation on cognitive function in older adults with and without cognitive impairment: A systematic review and meta-analysis.

Aerobic exercise (AE) may slow age-related cognitive decline. However, such cognition-sparing effects are not uniform across cognitive domains and studies. Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation and is also emerging as a potential alternative to pharmaceutical therapies. Like AE, the effectiveness of tDCS is also inconsistent for reducing cognitive impairment in ageing. The unexplored possibility exists that pairing AE and tDCS could produce synergistic effects and reciprocally augment cognition-improving effects in older individuals with and without cognitive impairments. Previous research found such synergistic effects on cognition when cognitive training is paired with tDCS in older individuals with and without mild cognitive impairment (MCI) or dementia. The purpose of this systematic review with meta-analysis was to explore if pairing AE with tDCS could augment singular effects of AE and tDCS on global cognition (GC), working memory (WM) and executive function (EF) in older individuals with or without MCI and dementia. Using a PRISMA-based systematic review, we compiled studies that examined the effects of AE alone, tDCS alone, and AE and tDCS combined on cognitive function in older individuals with and without mild cognitive impairment (MCI) or dementia. Using a PICOS approach, we systematically searched PubMed, Scopus and Web of Science searches up to December 2021, we focused on 'MoCA', 'MMSE', 'Mini-Cog' (measures) and 'cognition', 'cognitive function', 'cognitive', 'cognitive performance', 'executive function', 'executive process', 'attention', 'memory', 'memory performance' (outcome terms). We included only randomized controlled trials (RTC) in humans if available in English full text over the past 20 years, with participants' age over 60. We assessed the methodological quality of the included studies (RTC) by the Physiotherapy Evidence Database (PEDro) scale. Overall, 68 studies were included in the meta-analyses. AE (ES = 0.56 [95% CI: 0.28-0.83], p=0.01) and tDCS (ES = 0.69 [95% CI: 0.12-1.26], p=0.02) improved GC in all three groups of older adults combined (healthy, MCI, demented). In healthy population, AE improved GC (ES = 0.46 [95% CI: 0.22-0.69], p=0.01) and EF (ES = 0.27 [95% CI: 0.05-0.49], p=0.02). AE improved GC in older adults with MCI (ES = 0.76 [95% CI: 0.21-1.32], p=0.01). tDCS improved GC (ES = 0.69 [90% CI: 0.12-1.26], p=0.02), all three cognitive function (GC, WM and EF) combined in older adults with dementia (ES = 1.12 [95% CI: 0.04-2.19], p=0.04) and improved cognitive function in older adults overall (ES = 0.69 [95% CI: 0.20-1,18], p=0.01). Our systematic review with meta-analysis provided evidence that beyond the cardiovascular and fitness benefits of AE, pairing AE with tDCS may have the potential to slow symptom progression of cognitive decline in MCI and dementia. Future studies will examine the hypothesis of this present review that a potentiating effect would incrementally improve cognition with increasing severity of cognitive impairment.

The role of structured exercise interventions on cognitive function in older individuals with stable Chronic Obstructive Pulmonary Disease: A scoping review.

The methodological framework for scoping review was used and electronic searches of five databases performed. Original research and observational studies published between January 2010 and December 2021, administering exercise-based interventions and cognitive function evaluation, were included. Of 13 full-text manuscripts assessed for eligibility, five were allocated to analysis. Three studies administered exercise training within pulmonary outpatient rehabilitation program (PR), and one inpatient PR. The fifth study conducted a structured training intervention in which either aerobic or a combination with resistance exercises were included. Twelve cognitive function screening tools were used in the five studies included in the analysis. Results extracted were based on 245 COPD (33% female) with moderate to very-severe airflow limitation. Interventions ranged from 12 to 36 sessions. Studies reported statistically significant improvements after intervention in different cognitive function domains, such as global cognition, immediate and delayed recall ability, cognitive flexibility, verbal fluency, attention, abstract reasoning, praxis ability. Exercise-based interventions improve several areas of cognitive function in patients with stable COPD. However, the magnitude of gain varies among studies, and this is possibly due to the heterogeneity of tests used. Future research is needed to validate the optimal battery of screening tests, and to support the definition of guidelines for cognitive function evaluation in COPD.

Enhanced temporal complexity of EEG signals in older individuals with high cognitive functions.

Recent studies suggest that the maintenance of cognitive function in the later life of older people is an essential factor contributing to mental wellbeing and physical health. Particularly, the risk of depression, sleep disorders, and Alzheimer's disease significantly increases in patients with mild cognitive impairment. To develop early treatment and prevention strategies for cognitive decline, it is necessary to individually identify the current state of cognitive function since the progression of cognitive decline varies among individuals. Therefore, the development of biomarkers that allow easier measurement of cognitive function in older individuals is relevant for hyperaged societies. One of the methods used to estimate cognitive function focuses on the temporal complexity of electroencephalography (EEG) signals. The characteristics of temporal complexity depend on the time scale, which reflects the range of neuron functional interactions. To capture the dynamics, composed of multiple time scales, multiscale entropy (MSE) analysis is effective for comprehensively assessing the neural activity underlying cognitive function in the brain. Thus, we hypothesized that EEG complexity analysis could serve to assess a wide range of cognitive functions in older adults. To validate our hypothesis, we divided older participants into two groups based on their cognitive function test scores: a high cognitive function group and a low cognitive function group, and applied MSE analysis to the measured EEG data of all participants. The results of the repeated-measures analysis of covariance using age and sex as a covariate in the MSE profile showed a significant difference between the high and low cognitive function groups (F = 10.18, p = 0.003) and the interaction of the group × electrodes (F = 3.93, p = 0.002). Subsequently, the results of the post-hoc t-test showed high complexity on a slower time scale in the frontal, parietal, and temporal lobes in the high cognitive function group. This high complexity on a slow time scale reflects the activation of long-distance neural interactions among various brain regions to achieve high cognitive functions. This finding could facilitate the development of a tool for diagnosis of cognitive decline in older individuals.

Impact of Long-Term Exposure to Air Pollution on Cognitive Decline in Older Adults Without Dementia.

Air pollution control is necessary to decrease the burden on older adults with cognitive impairment, especially in low- and middle-income countries (LMICs). This study retrospectively examined the effect of cumulative exposure to air pollution, including NO2, SO2, CO, fine particulate matter (PM)10, PM2.5, and O3, on cognitive function in older individuals. Community-dwelling older adults who underwent the Mini-Mental State Examination (MMSE) from 2007 to 2018 were included in the analyses. We excluded older individuals diagnosed with dementia at baseline, while those who had completed more than two MMSE tests were included in the longitudinal analyses. Baseline MMSE and changes in MMSE scores were analyzed according to 5-year average concentrations of the district-level air pollutants, after controlling for covariates associated with cognitive decline in older adults. In total, 884,053 (74.3±7.1 years; 64.1% females) and 398,889 (72.3±6.4 years; 67.0% females) older individuals were included in the cross-sectional and longitudinal analyses, respectively. Older individuals exposed to higher levels of NO2, SO2, CO, and PM10 showed lower baseline MMSE scores. During follow-up, exposure to higher levels of NO2, SO2, CO, and PM10 was associated with greater decreases in MMSE scores in older individuals; for O3, the opposite pattern was observed. Our findings suggest that exposure to high levels of air pollutants can worsen the cognitive performance of older adults without dementia. Efforts to reduce air pollution in LMICs that have similar levels of pollutants to South Korea are necessary to reduce the burden on older adults with cognitive impairment.

Exploring Effects of Aerobic Exercise and Mindfulness Training on Cognitive Function in Older Adults at Risk of Dementia: A Feasibility, Proof-of-Concept Study.

This study sought to explore feasibility, acceptability, and preliminary effects of aerobic training (AT), mindfulness training (MT), or both (MT + AT) on cognitive function in older individuals at risk of dementia. Participants were randomized to AT, MT, both, or usual care (UC). Z-scores of attention, verbal fluency, and episodic memory for non-demented adults (ZAVEN) were computed at baseline, end of treatment (EOT), and 6months since baseline. Of the 36 enrolled participants (12M, 24F, mean age = 70.1years), 97% were retained in the study at 6months. At EOT, MT had higher ZAVEN scores than UC (b = .43, P =.03) and AT (b = .26, P = .10), while no differences were seen with MT + AT. A similar pattern was observed at a 6month follow-up (all P values = .10). MT may improve cognitive function in older individuals at risk of dementia. These preliminary findings need to be confirmed in a fully powered RCT.

An online investigation of the relationship between the frequency of word puzzle use and cognitive function in a large sample of older adults.

The identification of modifiable lifestyle factors to preserve cognitive function in older individuals becomes increasingly of importance. This study examines whether word puzzle use is related to cognitive function in older adults. Cognitive data from 19078 cognitively healthy individuals aged 50 to 93years enrolled into the online PROTECT study were evaluated for self-reported frequency of performing word puzzles on a six-point scale, ranging from "more than once per day" to "never". Nine cognitive tests covered a range of domains including focussed and sustained attention, information processing, executive function, working memory, and episodic memory. Analyses of covariance were used to determine any differences between the six response groups. Each of the 14 cognitive measures analysed showed highly statistically significant main effects of the frequency of performing word puzzles. For each measure, the group who never performed word puzzles performed most poorly, with the group who reported occasional puzzle use also performing more poorly than virtually every other group. Measures of speed provided the greatest discriminations, with a grammatical reasoning score differentiating the two highest frequency groups, performing word puzzles daily or more than once daily. The frequency of word puzzle use is directly related to cognitive function in adults aged 50 and over. Future work needs to determine whether engaging in such puzzles can favourably influence cognitive trajectory with age.

Uric Acid and Cognitive Function in Older Individuals.

Hyperuricemia has been recognized as an independent cardiovascular risk factor in epidemiological studies. However, uric acid can also exert beneficial functions due to its antioxidant properties, which may be particularly relevant in the context of neurodegenerative diseases. In this paper, we critically revise the evidence on the relationship between serum uric acid levels and cognitive function in older individuals, focusing on the etiology of cognitive impairment (Alzheimer’s disease, Parkinson’s dementia, and vascular dementia) and on the interactive connections between uric acid, dementia, and diet. Despite high heterogeneity in the existing studies, due to different characteristics of studied populations and methods of cognitive dysfunction assessment, we conclude that serum uric acid may modulate cognitive function in a different way according to the etiology of dementia. Current studies indeed demonstrate that uric acid may exert neuroprotective actions in Alzheimer’s disease and Parkinson’s dementia, with hypouricemia representing a risk factor for a quicker disease progression and a possible marker of malnutrition. Conversely, high serum uric acid may negatively influence the disease course in vascular dementia. Further studies are needed to clarify the physio-pathological role of uric acid in different dementia types, and its clinical-prognostic significance.

The Effects of Acute Aerobic Exercise on Cerebral Blood Flow and Cognition in Persons with Multiple Sclerosis

The Effects of Acute Aerobic Exercise on Cerebral Blood Flow and Cognition in Persons with Multiple Sclerosis

Ethnicity/culture modulates the relationships of the haptoglobin (Hp) 1-1 phenotype with cognitive function in older individuals with type 2 diabetes.

The haptoglobin (Hp) genotype has been associated with cognitive function in type 2 diabetes. Because ethnicity/culture has been associated with both cognitive function and Hp genotype frequencies, we examined whether it modulates the association of Hp with cognitive function. This cross-sectional study evaluated 787 cognitively normal older individuals (>65 years of age) with type 2 diabetes participating in the Israel Diabetes and Cognitive Decline study. Interactions in two-way analyses of covariance compared Group (Non-Ashkenazi versus Ashkenazi Jews) on the associations of Hp phenotype (Hp 1-1 versus non- Hp 1-1) with five cognitive outcome measures. The primary control variables were age, gender, and education. Compared with Ashkenazi Jews, non-Ashkenazi Jews with the Hp 1-1 phenotype had significantly poorer cognitive function than non-Hp 1-1 in the domains of Attention/Working Memory (p = 0.035) and Executive Function (p = 0.023), but not in Language/Semantic Categorization (p = 0.432), Episodic Memory (p = 0.268), or Overall Cognition (p = 0.082). After controlling for additional covariates (type 2 diabetes-related characteristics, cardiovascular risk factors, Mini-mental State Examination, and extent of depressive symptoms), Attention/Working Memory (p = 0.038) and Executive Function (p = 0.013) remained significant. Older individuals from specific ethnic/cultural backgrounds with the Hp 1-1 phenotype may benefit more from treatment targeted at decreasing or halting the detrimental effects of Hp 1-1 on the brain. Future studies should examine differential associations of Hp 1-1 and cognitive impairment, especially for groups with high prevalence of both, such as African-Americans and Hispanics.

Tracking early decline in cognitive function in older individuals at risk for Alzheimer disease dementia: the Alzheimer's Disease Cooperative Study Cognitive Function Instrument.

Several large-scale Alzheimer disease (AD) secondary prevention trials have begun to target individuals at the preclinical stage. The success of these trials depends on validated outcome measures that are sensitive to early clinical progression in individuals who are initially asymptomatic. To investigate the utility of the Cognitive Function Instrument (CFI) to track early changes in cognitive function in older individuals without clinical impairment at baseline. Longitudinal study from February 2002 through February 2007 at participating Alzheimer's Disease Cooperative Study sites. Individuals were followed up annually for 48 months after the baseline visit. The study included 468 healthy older individuals (Clinical Dementia Rating scale [CDR] global scores of 0, above cutoff on the modified Mini-Mental State Examination and Free and Cued Selective Reminding Test) (mean [SD] age, 79.4 [3.6] years; age range, 75.0-93.8 years). All study participants and their study partners completed the self and partner CFIs annually. Individuals also underwent concurrent annual neuropsychological assessment and APOE genotyping. The CFI scores between clinical progressors (CDR score, ≥0.5) and nonprogressors (CDR score, 0) and between APOE ε4 carriers and noncarriers were compared. Correlations of change between the CFI scores and neuropsychological performance were assessed longitudinally. At 48 months, group differences between clinical progressors and non-progressors were significant for self (2.13, SE=0.45, P<.001), partner (5.08, SE=0.59, P<.001), and self plus partner (7.04, SE=0.83, P<.001) CFI total scores. At month 48, APOE ε4 carriers had greater progression than noncarriers on the partner (1.10, SE=0.44, P<.012) and self plus partner (1.56, SE=0.63, P<.014) CFI scores. Both self and partner CFI change were associated with longitudinal cognitive decline (self, ρ=0.32, 95% CI, 0.13 to 0.46; partner, ρ=0.56, 95% CI, 0.42 to 0.68), although findings suggest self-report may be more accurate early in the process, whereas accuracy of partner report improves when there is progression to cognitive impairment. Demonstrating long-term clinical benefit will be critical for the success of recently launched secondary prevention trials. The CFI appears to be a brief, but informative potential outcome measure that provides insight into functional abilities at the earliest stages of disease.

Abstract 19813: Sleep Disturbance, Heart Failure, and Cognitive Function in Older Individuals: The Aging Demographics, and Memory Study (ADAMS)

Introduction: Approximately 50% of heart failure (HF) patients experience cognitive decline. In the general population, sleep disturbance is associated with cognitive decline. Sleep disturbance may alter the cellular or chemical homeostasis triggering cognitive decline. Up to 70% of individuals with HF report sleep disturbance. Although the etiology of cognitive decline in HF is unknown, sleep fragmentation and short sleep duration from sleep disturbance may partially explain cognitive decline among individuals with HF. This study investigates the possible mediating role of sleep disturbance on the relationship between HF and cognition. Methods: This cross-sectional study examined 856 older adults’ (mean age: 81.6 years, SD: 7.1, male: 355 (41%), Caucasian: 658 (77 %), HF: 100 (11.7%)) data from Aging, Demographics, and Memory Study. To explore the possibility of meditating effects of sleep disturbance on relationship between HF and cognition, we used a structural equation model. Cognition was measured by neuropyshological tests. Sleep disturbance was determined if a subject was positive on one of the following three questions: 1) “Do you have problem falling asleep?”, 2) “Do you wake frequently during sleep?”, and 3) “Do you wake up too early?” Results: Individuals with HF were likely to have a higher degree of sleep disturbance (β=0.229,p=0.003). Sleep disturbance was a significant predictor of cognitive decline (β=-6.52,p=0.028). However, there was no significant mediating effect of sleep disturbance on the relationship between HF and cognition (β=-0.011,p=0.978) after controlling for age, sex, and comorbidities. Conclusion: Findings from this study suggest that HF can exacerbate sleep disturbance and sleep disturbance can deteriorate cognition. However, the mediating role of sleep disturbance on the relationship between HF and cognitive decline remains questionable. Future studies using objective measures and longitudinal design would enhance our knowledge related to the relationship between heart failure, sleep disturbance, and cognition.

The Dose–response Relationship of Resistance Exercise on Cognitive Function in Older Individuals

The Dose–response Relationship of Resistance Exercise on Cognitive Function in Older Individuals