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Background: The Learning Ratio (LR) is a novel learning score that has shown improved utility over other learning metrics in detecting Alzheimer's disease (AD) across multiple memory tasks. However, its utility on the Consortium to Establish a Registry for Alzheimer's Disease Word List Memory Test (CERAD WLMT), a widely used list learning measure sensitive to decline in neurodegenerative disease, is unknown. The goal of the current study was to determine the utility of LR on the CERAD WLMT in differentiating between diagnostic (MiNCD vs MaNCD) and etiologic groups (VaD vs AD) in a veteran sample. Methods: Raw learning slope (RLS) and LR scores were examined in 168 veterans diagnosed with major neurocognitive disorder (MaNCD), mild neurocognitive disorder (MiNCD), or normal aging following neuropsychological evaluation. Patients with MaNCD were further classified by suspected etiology (i.e. microvascular disease vs AD). Results: Whereas RLS scores were not significantly different between MiNCD and MaNCD, LR scores were significantly different between all diagnostic groups (p's <.05). Those with AD had lower LR scores and RLS scores compared to those with VaD (p's <.05). LR classification accuracy was acceptable for MiNCD (AUC =.76), excellent for MaNCD (AUC =.86) and VaD (AUC =.81), and outstanding for AD (AUC =.91). Optimal cutoff scores for WLMT LR were derived from Youden's index. Conclusion: Results support the use of LR scores over RLS when interpreting the CERAD WLMT and highlight the clinical utility of LR in differentiating between diagnostic groups and identifying suspected etiology. [ABSTRACT FROM AUTHOR]

Objective Cognitive dispersion indexes intraindividual variability in performance across a battery of neuropsychological tests. Measures of dispersion show promise as markers of cognitive dyscontrol and everyday functioning difficulties; however, they have limited practical applicability due to a lack of normative data. This study aimed to develop and evaluate normed scores for cognitive dispersion among older adults. Method We analyzed data from 4,283 cognitively normal participants aged ≥50 years from the Uniform Data Set (UDS) 3.0. We describe methods for calculating intraindividual standard deviation (ISD) and coefficient of variation (CoV), as well as associated unadjusted scaled scores and demographically adjusted z -scores. We also examined the ability of ISD and CoV scores to differentiate between cognitively normal individuals (n  = 4,283) and those with cognitive impairment due to Lewy body disease (n  = 282). Results We generated normative tables to map raw ISD and CoV scores onto a normal distribution of scaled scores. Cognitive dispersion indices were associated with age, education, and race/ethnicity but not sex. Regression equations were used to develop a freely accessible Excel calculator for deriving demographically adjusted normed scores for ISD and CoV. All measures of dispersion demonstrated excellent diagnostic utility when evaluated by the area under the curve produced from receiver operating characteristic curves. Conclusions Results of this study provide evidence for the clinical utility of sample-based and demographically adjusted normative standards for cognitive dispersion on the UDS 3.0. These standards can be used to guide interpretation of intraindividual variability among older adults in clinical and research settings. [ABSTRACT FROM AUTHOR]

Serial position effects (SPEs) have shown promise as predictors of future cognitive decline and conversion from mild cognitive impairment (MCI) to Alzheimer's disease (AD), even when accounting for total learning and memory scores. However, conflicting results have been found in the literature, which may be at least partially related to the many ways in which SPEs are calculated. The current study aimed to address the discrepancies in the literature by examining whether one method of analyzing SPEs is more sensitive at distinguishing those with and without psychometrically defined MCI. 86 older adult participants (57 healthy comparison, 29 MCI) completed the California Verbal Learning Test, Third Edition (CVLT3) and the Rey Auditory Verbal Learning Test (RAVLT), along with measures assessing multiple cognitive domains. Each participant completed two visits, between 3 and 9 days apart, with a different memory measure administered on each day. The standard scoring approach and the regional scoring approach to calculating SPEs were compared. Results showed that, when significant differences were found, SPEs were always reduced in the MCI group compared to the healthy comparison group when using regional scoring; however, results were not as consistent when using standard scoring. Further, lower primacy than recency scores were only consistently seen in the MCI group when using the RAVLT but not the CVLT3. ROC analyses showed that only regional scoring of SPEs from delayed recall of the RAVLT and the CVLT3 accurately discriminated between those with and without MCI. Regional scoring of SPEs may be more sensitive at identifying subtle cognitive decline compared to standard scoring. However, the specific measure that is used to analyze SPEs can impact the interpretation of findings. [ABSTRACT FROM AUTHOR]

Objective: To examine predictors of informant-reported everyday functioning in mild cognitive impairment (MCI) and relations between everyday function and conversion to dementia. Methods: Informants of participants (n = 2614) with mild cognitive impairment (MCI) were administered the Functional Activities Questionnaire (FAQ). Changes in dimensions of functional ability as determined by an exploratory factor analysis (EFA) were examined over 3 years and participant predictors of change were examined using multilevel modeling (MLM). Results: The FAQ consisted of 3 factors, multistep, finance, and memory/orientation daily tasks. Impairment in memory/orientation tasks was significantly higher than impairment in multistep tasks. Worse functioning was associated with greater depression, worse memory, worse speed/EF, higher years of education and identifying as White. There was variability in some of these associations with different FAQ factors. Impairments in financial and memory/orientation daily tasks predicted follow-up conversion to dementia. Conclusions: Depression, speed/EF, and memory are consistently associated with domains of everyday functioning. Race, education, and age may be more variability associated with everyday functioning. Specific attention should be paid to subtle declines in the financial and memory/orientation domains as they may uniquely predict future dementia development. Depression may be a modifiable risk factor associated with functional impairment over time. [ABSTRACT FROM AUTHOR]

The Digit Span test is a widely used working memory measure. However, when using standardized scoring procedures, previous studies have demonstrated inconsistent relationships between Digit Span subtests and working memory measures frequently used in cognitive psychology experiments. Partial scoring involves awarding credit for all digits recalled in the correct serial location, whereas traditional scoring involves only awarding credit for a trial if all digits are recalled in the correct serial location. The current study compared the traditional all-or-nothing scoring method and the partial scoring method on Digit Span with other working memory measures and with measures of general fluid intelligence. The results showed that when differences were found, partial scoring was associated with stronger relationships with Digit Span Backwards but weaker relationships with Digit Span Forward and Sequencing compared with traditional scoring. These results support previous findings identifying differences between the Digit Span subtests and the utility of examining traditional scoring procedures. [ABSTRACT FROM AUTHOR]

Background: Gait-related changes in older adulthood may be related to changes in cognition (e.g., executive functioning), and recent work suggests that different self-reported measures of sleep may be tied to contrasting aspects of executive functioning. However, the relationship between these self-reported sleep measures and gait domains has not been explored. Such an investigation would be useful in helping to determine which older adults might exhibit changes in gait as well as experience other gait-associated changes (e.g., increased fall risk).Objective: To examine associations between different aspects of self-reported sleep and gait domains in a sample of cognitively healthy older adults.Method: A total of 423 older adults (mean age 69.9 years, range 50-92) completed self-report measures of sleep quality, daytime sleepiness, and sleep-related distress. The participants also completed an objective, electronic measure of both single-task and dual-task gait (i.e., GAITRite). Principal component analyses were used to elucidate the solution for each gait condition, and multiple linear regression was used to examine the contributions of sleep measures to variability in gait performance.Results: A 5-component solution of the single-task condition and a 4-component solution of the dual-task condition were identified. Multiple linear regressions revealed that a poorer sleep quality was associated with greater single-task and dual-task asymmetry. Greater daytime sleepiness was associated with increased dual-task gait variability and postural control. After controlling for the effects of other facets of sleep, sleep-related distress was not associated with any gait domain.Conclusions: Among cognitively healthy older adults,sleep quality and daytime sleepiness, but not sleep-related distress, are associated with aspects of gait. Patients who report these symptoms should be assessed and monitored for possible changes in gait. [ABSTRACT FROM AUTHOR]

Objectives: Projections from the United States Census Bureau suggest that the African American population may be the fastest growing race over the next 30 years and that they may be at the highest risk for developing dementia later in life. Various social factors have been shown to be associated with cognitive function and health outcomes. The present study aims to evaluate the relationship between social engagement and cognitive decline in a cohort of older African American adults. Methods: We utilized multilevel modeling to examine the association between cognitive decline and social engagement in a sample of 617 older African American adults. Results: Social activity was associated with global cognition, perceptual speed, perceptual orientation, and episodic memory over time. Loneliness was associated with better semantic memory performance over time. Perceived discrimination was associated with better semantic memory performance over time. Larger social network was associated with worse perceptual speed scores over time. Conclusions: Although our findings on loneliness and perceived discrimination over time were inconsistent with prior research, our findings on social activity and social network size over time were consistent with past literature and are thought to be due to positive social interactions providing a catalyst for cognitively stimulating activities. These results suggest that interventions designed to preserve cognition in African American older adults should incorporate adequate social activity. Furthermore, to maximize effectiveness, interventions should not necessarily focus on just expanding one's social network. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to examine neuropsychiatric symptom (NPS) factor severity progression over time in empirically derived (ED) mild cognitive impairment (MCI) subtypes. Methods: Participants in the Alzheimer's Disease Neuroimaging Initiative study diagnosed with MCI by Alzheimer's Disease Neuroimaging Initiative protocol using conventional clinical (CC) criteria (n = 788) were reclassified using cluster analysis as amnestic, dysnomic, dysexecutive MCI, or cluster‐derived normal (CC‐Normal) using empirical criteria. Cognitively normal (CN) participants (n = 207) were also identified. The Neuropsychiatric Inventory‐Questionnaire (NPI‐Q) was administered from baseline through 48‐month follow‐up. Exploratory factor analysis was completed to determine the NPI‐Q factor structure at 6‐month follow‐up. Multilevel modeling was used to determine NPI‐Q symptom severity factor and apathy symptom progression over time by cognitive subtype. Results: The exploratory factor analysis revealed that the NPI‐Q consisted of 2 factors: hyperactivity/agitation and mood symptoms. Using clinical and empirical criteria, all MCI groups were identified as having more severe hyperactivity/agitation symptoms than CN participants. However, only the amnestic MCI group identified using empirical criteria showed an increase in symptom severity over time relative to CN participants. Mood factor and apathy symptoms were found to be more severe in dysexecutive and amnestic groups in both models. Similarly, both models identified a significant worsening of mood and apathy symptoms over time for dysexecutive and amnestic groups relative to CN participants. Conclusions: This study provides further support that empirical criteria aid in examining the progression of clinical characteristics associated with MCI. Further, it helps to identify which MCI subtypes may be at higher risk for NPS progression. [ABSTRACT FROM AUTHOR]