Age, gender, and education norms on the CERAD neuropsychological battery in the oldest old

Measuring Multidimensional Aspects of Health in the Oldest Old Using the NIH Toolbox: Results From the ARMADA Study

OBJECTIVE

The percentage of older adults living into their 80s and beyond is expanding rapidly. Characterization of typical cognitive performance in this population is complicated by a dearth of normative data for the oldest old. Additionally, little attention has been paid to other aspects of health, such as motor, sensory, and emotional functioning, that may interact with cognitive changes to predict quality of life and well-being. The current study used the NIH Toolbox (NIHTB) to determine age group differences between persons aged 65-84 and 85+ with normal cognition.

METHOD

Participants were recruited in two age bands (i.e., 65-84 and 85+). All participants completed the NIHTB Cognition, Motor, Sensation, and Emotion modules. Independent-samples t-tests determined age group differences with post-hoc adjustments using Bonferroni corrections. All subtest and composite scores were then regressed on age and other demographic covariates.

RESULTS

The 65-84 group obtained significantly higher scores than the 85+ group across all cognitive measures except oral reading, all motor measures except gait speed, and all sensation measures except pain interference. Age remained a significant predictor after controlling for covariates. Age was not significantly associated with differences in emotion scores.

CONCLUSIONS

Results support the use of the NIHTB in persons over 85 with normal cognition. As expected, fluid reasoning abilities and certain motor and sensory functions decreased with age in the oldest old. Inclusion of motor and sensation batteries is warranted when studying trajectories of aging in the oldest old to allow for multidimensional characterization of health.

Associations between circadian alignment and cognitive functioning in a nationally representative sample of older adults

Proper alignment of activity-rest and light-dark patterns allows for healthy bodily functions to occur at optimal times of the day. Disruptions to this alignment may cause poor sleep as well as physical, mental, and cognitive problems. The purpose of this cross-sectional study was to determine if poorer circadian alignment was associated with decreased cognitive functioning among older (> 60 years) participants in the National Health and Nutrition Examination Survey. We utilized actigraphy-based rest-activity and dark-light measurements to calculate phasor magnitude (strength of circadian alignment coupling) and phasor angle (phase difference between activity-rest and light-dark cycles). Multiple linear regression models were used to determine associations of phasor magnitude and angle with performance in various cognitive tests, including Digit Symbol Substitution Test score (DSSS), CERAD Savings Percentage (CSP), and Animal Fluency Test (AFT) score. The results showed that a lower phasor magnitude (which indicates decreased strength of alignment coupling between rest-activity and dark-light cycles) was significantly associated with decreased DSSS (indicating slower processing speed and poorer working memory) when controlling for many important sociodemographic factors. However, this association became non-significant when accounting for sleep duration and total physical activity. Phasor angle did not have a significant association with any of the cognitive scores. Overall, we provided evidence indicating that circadian alignment may be a predictor of cognitive performance. Future studies should investigate whether improving circadian alignment may improve cognitive function and prevent cognitive decline.

Standing middle cerebral artery velocity predicts cognitive function and gait speed in older adults with cognitive impairment, and is impacted by sex differences

Upright posture challenges the cerebrovascular system, leading to changes in middle cerebral artery velocity (MCAv) dynamics which are less evident at supine rest. Chronic alterations in MCAv have been linked to hypoperfusion states and the effect that this may have on cognition remains unclear. This study aimed to determine if MCAv and oscillatory metrics of MCAv (ex. pulsatility index, PI) during upright posture are i) associated with cognitive function and gait speed (GS) to a greater extent than during supine rest, and ii) are different between sexes. Beat-by-beat MCAv (transcranial Doppler ultrasound) and mean arterial pressure (MAP, plethysmography) were averaged for 30-seconds during supine-rest through a transition to standing for 53 participants (73±6yrs, 17 females). While controlling for age, multiple linear regressions predicting MoCA scores and GS from age, supine MCAv metrics, and standing MCAv metrics, were completed. Simple linear regressions predicting Montreal Cognitive Assessment (MoCA) score and GS from MCAv metrics were performed separately for females and males. Significance was set to p<0.05. Lower standing diastolic MCAv was a significant (p = 0.017) predictor of lower MoCA scores in participants with mild cognitive impairment, and this relationship only remained significant for males. Lower standing PI was associated with slower GS (p = 0.027, r=-0.306) in both sexes. Our results indicate a relationship between blunted MCAv and altered oscillatory flow profiles during standing, with lower MoCA scores and GS. These relationships were not observed in the supine position, indicating a unique relationship between standing measures of MCAv with cognitive and physical functions.

Establishing normative data for the evaluation of cognitive performance in Huntington's disease considering the impact of gender, age, language, and education

BACKGROUND

A declining cognitive performance is a hallmark of Huntington's disease (HD). The neuropsychological battery of the Unified HD Rating Scale (UHDRS'99) is commonly used for assessing cognition. However, there is a need to identify and minimize the impact of confounding factors, such as language, gender, age, and education level on cognitive decline.

OBJECTIVES

Aim is to provide appropriate, normative data to allow clinicians to identify disease-associated cognitive decline in diverse HD populations by compensating for the impact of confounding factors METHODS: Sample data, N = 3267 (60.5% females; mean age of 46.9 years (SD = 14.61, range 18-86) of healthy controls were used to create a normative dataset. For each neuropsychological test, a Bayesian generalized additive model with age, education, gender, and language as predictors was constructed to appropriately stratify the normative dataset.

RESULTS

With advancing age, there was a non-linear decline in cognitive performance. In addition, performance was dependent on educational levels and language in all tests. Gender had a more limited impact. Standardized scores have been calculated to ease the interpretation of an individual's test outcome. A web-based online tool has been created to provide free access to normative data.

CONCLUSION

For defined neuropsychological tests, the impact of gender, age, education, and language as factors confounding disease-associated cognitive decline can be minimized at the level of a single patient examination.

Linear and Nonlinear Effect of Years of Schooling, Sex, and Age on the CERAD-MX and Complementary Tasks in a Mexican Sample: A Cross-Sectional Study

OBJECTIVE

Since evidence of adults' cognition decline is based on standardized testing, we developed regression-based continuous norms by linear regression (LR) and nonlinear quantile regression (NQR) with years of schooling (YoS), age, and sex as covariates on the Mexican adaptation of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD-MX) and complementary tasks.

METHODS

392 healthy, Spanish-speaking Mexican adults (50.25% women) aged 18-59 completed the 15 CERAD-MX cognitive tasks and complementary tasks. We used raw scores and examined YoS-related effects considering sex and age as covariates. For the NQR, we used calibrated scores for sex and age. While LR represents one line across the performance, NQR differentiated several nonlinear performance bands by quantiles.

RESULTS

LR showed positive relationships between YoS and cognitive performance with a funnel variance pattern. Therefore, this relationship is better represented with NQR than LR. A small, but significant, negative effect of age was found for this age range (18-59 years). The band with fewer years of schooling (1-6) showed greater variability in the cognitive measures than those with more years of schooling (16-22).

CONCLUSION

This study shows that NQR is useful for accurately positioning participants' performance relative to their peers. NQR accounts more than LR for the inconsistent variability of cognitive performance as a function of YoS by identifying the variability according to YoS (low, medium, high). Thus, NQR represents an appropriate way to construct norms for the cognitive performance of adults.

Evaluating memory testing to distinguish dementia severity among White, Black, and Spanish-speaking individuals in the Uniform Data Set (UDS)

INTRODUCTION

Little work has compared the effectiveness of using multiple types of memory tests alone or in combination to distinguish dementia severity in diverse research cohorts including Black individuals and Spanish speakers. Here we evaluate word list and paragraph recall tests to distinguish cognitively normal, mild cognitively impaired, and those with Alzheimer's disease in diverse cohorts.

METHODS

Using Uniform Data Set (UDS) and site-specific supplemental data, logistic regression models and receiver operating characteristic-area under the curve were used to compare paragraph recall versus word list in differentiating among Clinical Dementia Rating (CDR) scale level.

RESULTS

Results reveal high discriminability for all groups and no difference between either test in distinguishing between CDR levels. Combining tests improved discriminability for the whole group but did not for Black individuals or Spanish speakers.

DISCUSSION

Our findings indicate that using multiple memory tests may not improve differentiation between cognitive impairment levels for diverse cohorts. The burden of added testing may be a barrier for maximizing inclusion of under-represented groups in research.

Visuospatial and Verbal Memory Differences in Amish Individuals With Alzheimer Disease and Related Dementias

BACKGROUND

Verbal and visuospatial memory impairments are common to Alzheimer disease and Related Dementias (ADRD), but the patterns of decline in these domains may reflect genetic and lifestyle influences. The latter may be pertinent to populations such as the Amish who have unique lifestyle experiences.

METHODS

Our data set included 420 Amish and 401 CERAD individuals. Sex-adjusted, age-adjusted, and education-adjusted Z-scores were calculated for the recall portions of the Constructional Praxis Delay (CPD) and Word List Delay (WLD). ANOVAs were then used to examine the main and interaction effects of cohort (Amish, CERAD), cognitive status (case, control), and sex on CPD and WLD Z-scores.

RESULTS

The Amish performed better on the CPD than the CERAD cohort. In addition, the difference between cases and controls on the CPD and WLD were smaller in the Amish and Amish female cases performed better on the WLD than the CERAD female cases.

DISCUSSION

The Amish performed better on the CPD task, and ADRD-related declines in CPD and WLD were less severe in the Amish. In addition, Amish females with ADRD may have preferential preservation of WLD. This study provides evidence that the Amish exhibit distinct patterns of verbal and visuospatial memory loss associated with aging and ADRD.

Risk Factors for Various Cognitive Function Decline Trajectories in Adults Over 40 Years of Age: A Retrospective Cohort Study

OBJECTIVE

The aims of our study were to identify distinct trajectories of cognitive function using the group-based trajectory model. We also investigate which demographic factors act as risk factors for cognitive decline in each group.

METHODS

The data from the Seoul National University Hospital Healthcare System Gangnam Center, from 2005 to 2019. The number of study subjects was 637. We used a group-based model to identify cognitive function trajectories. Multinomial logistic regression was employed to define risk factors for cognitive function decline.

RESULTS

The cognitive function trajectories among adults over 40 years of age were heterogeneous. We identified four trajectories: high (27.3%), medium (41.0%), low (22.7%), and rapid decline (9.1%). Older age, male, low educational level, bad dietary habits, diabetes mellitus, technical worker, and lower income increased the likelihood of a cognitive function decline.

CONCLUSION

A younger age, a higher educational level, professional worker, good dietary habits, no diabetes mellitus, and no obesity improved cognitive function. A combination of these factors can improve "cognitive reserve" and delay cognitive decline. Interventions to prevent cognitive decline are needed after identification of high-risk groups for cognitive decline.

Does peak expiratory flow moderate trajectories of cognitive function among individuals with lung diseases? A longitudinal analysis of the National Health and Aging Trends Study

INTRODUCTION

Impaired cognitive function can co-exist in chronic respiratory diseases. However, it is not clear if peak expiratory flow (PEF) impacts changes in cognitive function. Our objective was to explore whether peak expiratory flow moderates trajectories of memory, visuospatial abilities, and executive function in individuals with chronic respiratory diseases.

METHODS

This was an analysis of individuals with lung diseases from the National Health and Aging Trends Study. Multivariable-adjusted generalized linear mixed models were used to estimate trajectories of immediate and delayed recall, and clock drawing over a 10-year follow-up. The interaction between PEF and time were plotted using sex-specific values for peak expiratory flow at 10th, 50th and 90th percentiles.

RESULTS

In females, interactions of time-by-PEF were found for both immediate (n = 489, t = 2.73, p<0.01) and delayed recall (n = 489, t = 3.38, p<0.01). Females in the 10th vs. 90th percentile of PEF declined in immediate recall at 0.14 vs. 0.065 words/year, and 0.17 vs. 0.032 words/year for delayed recall. Among males, recall declined linearly over 10 years (immediate recall: n = 296, t = -3.08, p < 0.01; delayed recall: n = 292, t = -2.46, p = 0.02), with no interaction with PEF. There were no time-by-PEF interactions nor declines over time in clock drawing scores in both sexes (females: n = 484, t = 0.25, p = 0.81; males: n = 291, t = -0.61, p = 0.55).

CONCLUSION

Females with the lowest PEF values experienced the greatest rates of decline in immediate and delayed recall over 10 years of follow-up, whereas males experienced similar declines in memory outcomes across all levels of PEF. Clock drawing scores remained stable over 10 years in both sexes.

The CERAD Word List Memory Test: Normative Data Based on a Norwegian Population-Based Sample of Healthy Older Adults 70 Years and Above. The HUNT Study

BACKGROUND

The CERAD Word List Memory Test (WLMT) is widely used in the assessment of older adults with suspected dementia. Although normative data of the WLMT exist in many different regions of the world, normative data based on large population-based cohorts from the Scandinavian countries are lacking.

OBJECTIVE

To develop normative data for the WLMT based on a large population-based Norwegian sample of healthy older adults aged 70 years and above, stratified by age, gender, and education.

METHODS

A total of 6,356 older adults from two population-based studies in Norway, HUNT4 70 + and HUNT4 Trondheim 70+, were administered the WLMT. Only persons with normal cognitive function were included. We excluded persons with a diagnosis of mild cognitive impairment (MCI) and dementia, and persons with a history of stroke and/or depression. This resulted in 3,951 persons aged between 70 and 90 years, of whom 56.2% were females. Regression-based normative data were developed for this sample.

RESULTS

Age, gender, and education were significant predictors of performance on the WLMT list-learning subtests and the delayed recall subtest, i.e., participants of younger age, female sex, and higher education level attained higher scores compared to participants of older age, male sex, and lower level of education.

CONCLUSION

Regression-based normative data from the WMLT, stratified by age, gender, and education from a large population-based Norwegian sample of cognitively healthy older adults aged 70 to 90 years are presented. An online norm calculator is available to facilitate scoring of the subtests (in percentiles and z-scores).

Systolic blood pressure at age 40 and cognitive function 25 years later: the Akershus Cardiac Examination (ACE) 1950 Study

OBJECTIVES

Hypertension in midlife is a risk factor for cognitive impairment. Still, the ideal midlife blood pressure (BP) remains unknown. We examined associations between different systolic blood pressure (SBP) levels at the age of 40-43 years and change in SBP over a 25-year period with cognitive function at age 62-65 years.

METHODS

We included 2424 individuals born in 1950 who had participated both in the Age 40 Program (1990-1993) and the Akershus Cardiac Examination (ACE) 1950 Study (2012-2015). The exposure was SBP at age 40-43 years and the outcome was cognitive function at age 62-65 years, assessed with Montreal Cognitive Assessment, Delayed recall trial from the Consortium to Establish a Registry for Alzheimer's Disease Word List Memory Task, and Trail Making Test part B (TMT B).

RESULTS

Participants were 40.1 ± 0.3 years old with mean SPB 128 ± 13 mmHg at the Age 40 Program, and 63.9 ± 0.6 years old with mean SPB 138 ± 18 at the ACE 1950 Study. Adjusted linear regressions showed no associations between SBP and subsequent cognitive function. In logistic regressions, individuals with SBP ≥140 mmHg, compared to individuals with SBP <120 mmHg (odds ratio 2.29, 95% confidence interval 1.28-4.10, P-value 0.005) had increased risk of an abnormal TMT B-score. Change in SBP during the 25-year follow-up was not associated with cognitive function.

CONCLUSIONS

SBP ≥140 mmHg at age 40-43 was associated with reduced capacity on TMT B, a domain specific cognitive test sensitive to vascular impairment. No other associations were found between SBP, or change in SBP, and cognitive function.

Elevated Anxious and Depressed Mood Relates to Future Executive Dysfunction in Older Adults: A Longitudinal Network Analysis of Psychopathology and Cognitive Functioning

Vulnerability models posit that executive-functioning (EF) problems centrally affect future common (vs. rare) psychopathology symptoms. Conversely, scar theory postulates that depression/anxiety (vs. other psychopathology) symptoms centrally influence reduced EF. However, most studies so far have been cross-sectional. We used cross-lagged panel network analysis to determine temporal and component-to-component relations on this topic. Community older adults participated across four time points. Cognitive tests and the caregiver-rated Neuropsychiatric Inventory assessed nine psychopathology and eight cognitive-functioning nodes. Nodes with the highest bridge expected influence cross-sectionally were agitation and episodic memory. Episodic memory had the strongest inverse relation with age. Agitation had the strongest negative association with global cognition. EF nodes tended to be centrally affected by prior depressed and anxious moods rather than influential on any future nodes. Heightened anxious and depressed mood (vs. other nodes) centrally predicted future decreased EF-related (vs. non-EF-related) nodes in older adults, supporting scar (vs. vulnerability) theory.

Sex Differences in Cognition Across Aging

Sex and gender differences are seen in cognitive disturbances in a variety of neurological and psychiatry diseases. Men are more likely to have cognitive symptoms in schizophrenia whereas women are more likely to have more severe cognitive symptoms with major depressive disorder and Alzheimer's disease. Thus, it is important to understand sex and gender differences in underlying cognitive abilities with and without disease. Sex differences are noted in performance across various cognitive domains - with males typically outperforming females in spatial tasks and females typically outperforming males in verbal tasks. Furthermore, there are striking sex differences in brain networks that are activated during cognitive tasks and in learning strategies. Although rarely studied, there are also sex differences in the trajectory of cognitive aging. It is important to pay attention to these sex differences as they inform researchers of potential differences in resilience to age-related cognitive decline and underlying mechanisms for both healthy and pathological cognitive aging, depending on sex. We review literature on the progressive neurodegenerative disorder, Alzheimer's disease, as an example of pathological cognitive aging in which human females show greater lifetime risk, neuropathology, and cognitive impairment, compared to human males. Not surprisingly, the relationships between sex and cognition, cognitive aging, and Alzheimer's disease are nuanced and multifaceted. As such, this chapter will end with a discussion of lifestyle factors, like education and diet, as modifiable factors that can alter cognitive aging by sex. Understanding how cognition changes across age and contributing factors, like sex differences, will be essential to improving care for older adults.

Associations between Metal Exposures and Cognitive Function in American Older Adults

Cognitive function frequently declines with older age, independently of the development of neurodegenerative diseases, and few interventions are known to counter this decline. Exposure to neurotoxic metals may contribute to this decline in cognitive function in older adults. Using the National Health and Nutrition Examination Survey (NHANES) data, the performance of 3042 adults aged 60 years and older on three cognitive tests for immediate, delayed, and working memory were examined in relation to blood concentrations of seven metals and metalloids and urinary concentrations of nineteen metals and metabolites. Using linear regression models, associations between cognitive tests and logarithms of metal exposures were adjusted for age, sex, ethnicity, education level, depression, diabetes, alcohol consumption, and cigarette use. Increased selenium was strongly associated with better performance on all three cognitive tests. Cadmium and lead were negatively associated with performance on all three cognitive tests. Some urinary metabolites of arsenic, urinary lead, cadmium, and tungsten were significantly associated with poor performance on some tests. In older adults, higher selenium levels were strongly associated with better cognitive performance.

Markers of a plant-based diet relate to memory and executive function in older adults

BACKGROUND

Although it is known that plant-based foods are important for physical health, little is known about the relationship between plant-based foods and cognitive health. Emerging evidence suggests that some macronutrients may influence cognition, but it is unclear which domains of cognition are involved; more importantly, it is unknown how a plant-based diet relates to cognition.

OBJECTIVE

To examine associations between a plant-based dietary pattern and cognitive functioning.

METHODS

Participants were 3,039 older adults who participated in the 2011-2014 waves of the National Health and Nutrition Examination Survey (NHANES). The present cross-sectional study used data on macronutrient intake from 24-hour dietary interviews, as well as performance on tests of long-term memory and executive function (i.e., delayed word recall, digit symbol substitution test, and animal fluency). Principal component analysis was used to extract a dietary pattern consistent with a plant-based diet.

RESULTS

Greater adherence to a dietary pattern consistent with a plant-based diet was related to better performance on all cognitive tasks. Secondary analyses indicated that the associations between a plant-based dietary pattern and executive function accounted for the association between a plant-based dietary pattern and memory. Furthermore, this same plant-based dietary pattern was associated with reduced baseline inflammation in a separate dataset.

CONCLUSIONS

Experimental manipulations are needed to determine the potential causal relations of these associations, but these results suggest that a plant-based diet relates to better cognition, especially through improved executive control. Future work should also attempt to extend these results by examining potential mechanisms underlying these associations, such as reduced inflammation.

Normative Data for the CERAD-NP for Healthy High-Agers (80-84 years) and Effects of Age-Typical Visual Impairment and Hearing Loss

OBJECTIVES

This study aims to establish reference data for nondemented adults between 80 and 84 years of age based on the German version of the Consortium to Establish a Registry for Alzheimer's disease Neuropsychological (CERAD-NP) test battery and to assess the possible influence of hearing and vision impairments on CERAD-NP performance.

METHODS

Two hundred one volunteers were examined with the German CERAD-NP test battery, and 18 test scores were calculated from the data. The sample included 99 men (49%), the mean age was 81.8 years (SD = 1.3), and the mean years of education were 13.9 (SD = 3.1). Percentiles for continuous and percentile ranks for discrete test scores were calculated separately for four norm groups. The groups were classified according to gender and education. Multiple regression analysis was used to predict cognitive performance from visual acuity and hearing ability.

RESULTS

The normative data obtained were consistent with other findings from younger and older age groups. Worse visual acuity predicted slower performance in the Trail Making Test (TMT). None of the other CERAD-NP tests were correlated to sensory functions.

CONCLUSIONS

Using age-appropriate reference data, such as that established here for the 80-84 year age group can help to improve the detection of cognitive decline and prevent biases that arise when old-old adults are compared to younger old adults. Visual acuity should be considered an influencing factor on TMT performance.

Associations between body composition and cognitive function in an elderly Korean population: A cohort-based cross-sectional study

The prevalence of obesity as well as cognitive impairment increases with age. Previous studies showed that obesity is associated with an increased risk of cognitive impairment and dementia. Body composition changes occur as part of the aging process; therefore, the assessment of obesity in elderly populations should include body composition as well as body weight. This study investigated the relationship between body mass index (BMI), body composition, and cognitive function in a community-dwelling elderly Korean population.This cohort-based cross-sectional analysis included 2386 elderly participants aged between 70 and 84 years from the Korean Frailty and Aging Cohort Study for 2016 to 2017. To investigate the relationship between body composition and cognitive function in community-dwelling individuals, BMI and body composition, including total and trunk fat mass and fat-free mass, were measured by dual-energy X-ray absorptiometry. Fat mass index (FMI), trunk fat mass index (TFMI), and fat-free mass index (FFMI) were used to represent the body composition. A short form of the Korean version of the Consortium to Establish a Registry for Alzheimer disease was used to assess cognitive function. To evaluate the relationship between variables, simple and fully adjusted multivariable analyses were performed using generalized linear regression models.The mean ages were 76.8 years for males and 76.1 years for females. The BMI of male participants was significantly lower than that of females (23.9 ± 2.89 vs 24.7 ± 3.02 kg/m2, P < .001). Among body composition parameters, the differences in FMI (6.44 ± 1.97 vs 9.29 ± 2.3 kg/m2), TFMI (3.68 ± 1.33 vs 5.03 ± 1.43 kg/m2), and FFMI (17.4 ± 1.64 vs 15.3 ± 1.39 kg/m2) were statistically significant. In linear regression analyses, BMI, FMI, and TFMI showed significant positive correlations with mini-mental state examination in the Korean version of the CERAD assessment packet; wordlist memory, recall, and recognition; and frontal assessment battery only in males. The significant positive correlations persisted even after fully adjusting for age, education periods, location of residence, depression, marriage, annual income, presence of diabetes mellitus, dyslipidemia, and hypertension. However, no significant correlations in either sex were observed between FFMI and cognitive functions in the fully adjusted models.In this study, BMI, and fat mass-related indexes including FMI and TFMI showed a positive linear correlation with cognitive functions but not FFMI. Moreover, the findings were significant only in men. Besides the difference between sexes, the results of this study showed a more apparent correlation in fat mass than in fat-free mass that comprises body weight.

Normative Data for the ELSA-Brasil Neuropsychological Assessment and Operationalized Criterion for Cognitive Impairment for Middle-Aged and Older Adults

OBJECTIVES

Normative data should consider sociodemographic diversity for the accurate diagnosis of cognitive impairment. This study aims to provide normative data for a brief neuropsychological battery and present diagnostic criteria for cognitive impairment that could be used in primary care settings.

METHODS

We selected 9618 Brazilian middle-aged and older adults after detailed exclusion criteria to avoid subtle cognitive impairment. We analyzed age, sex, and education influence on cognitive performance. To verify the evidence of criterion validity, we compared the cognitive performance of subjects with and without a depressive episode. Additionally, we verified the percentage of spurious scores under three different cutoffs.

RESULTS

Age and education had the greatest impact on cognition. Normative scores were provided according to age and education groups. Participants with a depressive episode performed poorer than control subjects. The clinical cutoff of at least two scores below the 7th percentile revealed the adequate percentage of spurious and possible clinical performance.

CONCLUSIONS

The Longitudinal Study on Adult Health (ELSA-Brasil) provided normative data based on a unique selected set of cognitively normal subjects. Normative groups were selected based on age and education, and the battery was sensitive to the presence of a depressive episode. We suggested clinical cutoffs for the tests in this battery that could be used in primary care settings to improve the accurate diagnosis of cognitive impairment.

Gait variability across neurodegenerative and cognitive disorders: Results from the Canadian Consortium of Neurodegeneration in Aging (CCNA) and the Gait and Brain Study

Introduction

Gait impairment is common in neurodegenerative disorders. Specifically, gait variability—the stride‐to‐stride fluctuations in distance and time—has been associated with neurodegeneration and cognitive impairment. However, quantitative comparisons of gait impairments across the cognitive spectrum of dementias have not been systematically investigated.

Methods

Older adults (N = 500) with subjective cognitive impairment, Parkinson disease (PD), mild cognitive impairment (MCI), PD‐MCI, Alzheimer's disease (AD), PD‐dementia, Lewy body dementia, and frontotemporal dementia, as well cognitive normal controls, who were assessed for their gait and cognitive performance.

Results

Factor analyses grouped 11 quantitative gait parameters and identified four independent gait domains: rhythm, pace, variability, and postural control, for group comparisons and classification analysis. Among these domains, only high gait variability was associated with lower cognitive performance and accurately discriminated AD from other neurodegenerative and cognitive conditions.

Discussion

Our findings indicate that high gait variability is a marker of cognitive‐cortical dysfunction, which can help to identify Alzheimer's disease dementia.

Episodic Memory and Verbal Fluency Tasks: Normative Data from Nine Nationally Representative Samples

OBJECTIVE

This study aims to generate country-specific norms for two episodic memory tasks and a verbal fluency test among middle-aged and older adults using nationally representative data from nine low-, middle-, and high-income countries.

METHOD

Data from nine countries in Africa, Asia, Europe, and Latin America were analyzed (n = 42,116; aged 50 years or older). Episodic memory was assessed with the word list memory (three trials of immediate recall) and word list recall (delayed recall). Verbal fluency was measured through the animal naming task. Multiple linear regression models with country-specific adjustments for gender, age, education, and residential area were carried out.

RESULTS

Both age and education showed high influence on test performance (i.e. lower cognitive performance with increasing age and decreasing years of education, respectively), while the effect of sex and residential area on cognitive function was neither homogeneous across countries nor across cognitive tasks.

CONCLUSIONS

Our study provided sex-, age-, education-, and residential area-specific regression-based norms that were obtained from one of the largest normative study worldwide on verbal recall and fluency tests to date. Findings derived from this study will be especially useful for clinicians and researchers based at countries where cognitive norms are limited.

Association between Vitamin B12 levels and cognitive function in the elderly Korean population

Vitamin B12 (B12), also known as cobalamin, is a water-soluble vitamin. It is a cofactor in DNA synthesis and is involved in the metabolism of every cell of the human body, including the central nervous system. Those with a deficiency of B12 can present with peripheral neuropathy, pernicious anemia, or a cognitive disorder. Previous studies have revealed that a deficiency of B12 is associated with cognitive decline or Alzheimer disease.The data of 2991 people were evaluated from 2 years of the Korean Frailty and Aging Cohort Study, a nationwide multicenter survey. To assess cognitive function, a short form of the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD-K) was used. Of the CERAD-K tests, we included the Mini-Mental State Examination in the Korean version of the CERAD assessment packet (MMSE-KC), the word list: memory/recall/recognition, digit span (forward, backward), trail making test-A, and the frontal assessment battery. B12 concentrations were classified into clinically relevant categories, insufficient (<350 pg/mL) and sufficient (≥350 pg/mL). A linear regression analysis was used to evaluate the relationship between cognitive function and B12 levels.The mean age of the 2991 participants was 76.4 ± 3.9 years old. Overall, 414 (13.8%) were classified as B12 insufficient, and 2577 (86.2%) as B12 sufficient. The sufficient B12 group performed better in the MMSE-KC, Wordlist: memory, Wordlist: recognition, TMT-A test, digit span, and FAB tests. This was statistically significant (P < .05). However, in the multivariable linear regression analysis, after adjusting for age, sex, education period, marriage, smoking and drinking habits, and comorbidities, the association between the B12 group and cognitive function was not statistically significant.Although our study does not show that B12 insufficiency is a direct risk factor to cognitive decline, B12 levels could be a contributing factor to cognitive function. Our results suggest that cognition was affected by the B12 levels, along with demographic and sociological variables.

Normative data for the 10/66 dementia research group neuropsychological test battery from Singapore's older adult population

Cognitive impairment in older adults is a major public concern for Singapore's aging population. The study aimed to (1) examine the effects of age, gender, and education on neuropsychological test performance, and (2) establish regression-based norms in the Singapore older adult (≥ 60 years) population. Data on neuropsychological test performance was extracted from the Well-being of the Singapore Elderly (WiSE) study (n = 2033). Participants who met criteria for dementia were excluded. The data included scores from the 10/66 Dementia Research Group neuropsychological test battery measuring verbal fluency, immediate memory recall, delayed memory recall, and global cognitive function. The General Linear Model (GLM) was used to examine the effects of age, gender, and education on neuropsychological test performance. Stratified weighted means and standard deviations by age, gender and education were reported to establish regression-based normative data. Results from GLM showed that older age and having lower education were associated with poorer performance on all four neuropsychological test measures, and females showed better performance on the tests for immediate memory recall and delayed memory recall. The current study provides useful information on cognitive functioning based on the 10/66 neuropsychological test battery in the older adult population in Singapore. This may help to improve neuropsychological assessments for older adults.

Cognitive and Motor Norms for Huntington’s Disease

Background

The progression of Huntington’s disease (HD) for gene-expanded carriers is well-studied. Natural aging effects, however, are not often considered in the evaluation of HD progression.

Objective

To examine the effects of natural aging for healthy controls and to develop normative curves by age, sex, and education from the distribution of observed scores for the Symbol Digit Modalities Test, Stroop Word Reading Test, Stroop Color Naming Test, Stroop Interference Test, Total Motor Score, and Total Functional Capacity (TFC) from the Unified Huntington’s Disease Rating Scale (UHDRS) along with a composite score.

Methods

After combining longitudinal REGISTRY and Enroll-HD data, we used quantile regression and natural cubic splines for age to fit models for healthy controls (N = 3,394; N observations = 8,619). Normative curves were estimated for the 0.05, 0.25, 0.50, 0.75, and 0.95 quantiles. Two types of reference curves were considered: unconditional curves were dependent on age alone, whereas conditional curves were dependent on age and other covariates, namely sex and education.

Results

Conditioning on education was necessary for the Symbol Digit, Stroop Word, Stroop Color, Stroop Interference, and composite UHDRS. Unconditional curves were sufficient for the Total Motor Score. TFC was unique in that the curve was constant over age with its intercept at the maximum score (TFC = 13). For all measures, sex effects were minimal, so conditioning on sex was unwarranted.

Conclusions

Extreme quantile estimates for each measure can be considered as boundaries for natural aging and scores falling beyond these thresholds are likely the result of disease progression. Normative curves and tables are developed and can serve as references for clinical characterization in HD.

The five-items memory screen-extended variant: A tool for assessing memory

BACKGROUND AND PURPOSE

The detection of memory impairment is an important part of dementia screening. However, the scope of memory measures in current screening batteries is limited. There is a need for a short yet sensitive instrument for early detection of memory impairment that could serve as a complement to existing globally oriented screening tests, for example, Mini-Mental State Examination (MMSE). To that end, the current study investigates the sensitivity and psychometric properties of the memory screening instrument The Five-Items Memory Screen -Extended Variant (FIMS-XV).

METHODS

Hundred and forty-five participants included in the Gothenburg Mild Cognitive Impairment Study-27 patients with subjective cognitive impairment (SCI), 73 with mild cognitive impairment (MCI), and 45 with mild dementia-underwent cognitive screening including the MMSE and FIMS-XV. Ninety participants also underwent extensive neuropsychological testing.

RESULTS

The FIMS-XV showed high internal consistency and strong correlations with established neuropsychological memory tests. Both the FIMS-XVdelayed recall score and the FIMS-XV total score differentiated mild dementia patients from patients with SCI and MCI.

CONCLUSIONS

The FIMS-XV shows promise as a sensitive tool for screening for memory impairment in all putative phases of dementia.

Association between vitamin D deficiency and cognitive function in the elderly Korean population: A Korean frailty and aging cohort study

It is well known that vitamin D (VitD) plays an important role in bone and calcium metabolism in the human body. VitD has additional roles in the body including modulation of cell growth, neurogenesis, neuroprotection, detoxification, immune function, and reduction of inflammation. Recent studies reveal insufficiency of VitD as a risk factor for cognitive decline or dementia. VitD has a role in normal brain function; insufficiency of VitD may lead to decreased memory and cognitive function.Using 2 years of baseline data from Korean frailty and aging cohort study, 2990 subjects (1415 men and 1575 women) were recruited. A short form of Korean version of the consortium to establish a registry for Alzheimer disease (CERAD-K), an assessment of cognitive status in patients with dementia was used. Among CERAD-K tests, we included word list memory/recall/recognition, digit span (forward, backward), trail making test (TMT) A, and mini-mental state examination in the Korean version of the CERAD assessment packet (MMSE-KC). Serum samples were collected and 25-hydroxyvitamin D (25(OH)D) was measured. Serum 25(OH)D concentrations were classified into clinically relevant categories as: deficient (<10 nmol/L), insufficient (10-30 nmol/L), and sufficient (≥30 nmol/L).The mean age of participants was 76.5 ± 3.9 years, and 52.7% were women. Among 2990 participants, 119 (4.0%) were classified as 25(OH)D deficient and 2253 (75.3%) as insufficient. Only 618 (20.7%) participants were sufficient for 25(OH)D. Among them performance in MMSE-KC, TMT A, and digit span tests was better in sufficient, insufficient, and deficient groups, which was statistically significant (P < .05). However, in multivariable regression analysis after adjusting for age, sex, body mass index, education, center, seasonality, physical activity, and alcohol use, association between 25(OH)D and cognitive function was not statistically significant.Although, when comparing VitD levels, there were differences in cognitive tests among the groups, fully adjusted analysis did not show any association. This result suggests that cognition was not affected by VitD levels alone but also population and sociological variables. In a fully adjusted model, there was no statistically significant association between VitD and cognitive function in the elderly Koreans in logistic regression analysis.

Short-term computerized cognitive training does not improve cognition compared to an active control in non-demented adults aged 80 years and above

BACKGROUND

Older adults, especially those above age 80, are the fastest growing segment of the population in the United States and at risk for age-related cognitive decline and dementia. There is growing evidence that cognitive activity and training may allow adults to maintain or improve cognitive functioning, but little is known about the potential benefit in the oldest old. In this randomized trial, the effectiveness of a computerized cognitive training program (CCT program) was compared to an active control games program to improve cognition in cognitively normal individuals aged 80 and older.

METHODS

Sixty-nine older adults were randomized to a 24-session CCT program (n = 39) or an active control program (n = 30). Participants completed a pre- and post- training neuropsychological assessment. The primary outcome measure was a global cognitive composite, and the secondary outcomes were the scores on specific cognitive domains (of memory, executive function/attention, and language).

RESULTS

Using linear mixed models, there were no significant differences between the CCT and the active control program on the primary (p = 0.662) or any of the secondary outcomes (language functioning, p = .628; attention/executive functioning, p = .428; memory, p = .749).

CONCLUSION

This study suggests that short-term CCT had no specific benefit for cognitive functioning in non-demented individuals aged 80 and older.

The CADM2 gene is associated with processing speed performance - evidence among elderly with type 2 diabetes

Objectives: Recent large-scale meta-analysis of genome-wide association studies (GWAS) from multiple cohorts, demonstrated the association of the single nucleotide polymorphism (SNP) rs17518584, with processing speed (measured by the Digit Symbol Substitution Test (DSST) or the Letter Digit Substitution Test (LDST)), at GWAS significance level. This SNP is located within the cell adhesion molecule 2 (CADM2) gene. We aimed to validate this finding in our sample of 944 cognitively normal Jewish elderly individuals with type 2 diabetes (T2D), a population which is at risk for cognitive decline and dementia.Methods: Using linear regression, we studied the association of rs17518584 with DSST performance, adjusting for demographic, T2D-related characteristics and cardiovascular factors. In secondary analyses, associations with performance in four cognitive domains (episodic memory, language/semantic categorisation, attention/working memory and executive function) and overall cognition were examined.Results: Controlling for sex, age at cognitive assessment, years of education and ancestry, we found a significant association of rs17518584 with DSST performance (P = 0.013), consistent with the originally reported effect direction. Results remained significant even when the additional covariates (T2D-related and cardiovascular factors) were included in the analysis (P = 0.034). Moreover, this SNP was significantly associated with performance in the cognitive domains of language/semantic categorisation and executive function, as well as overall cognition.Conclusions: Taken together, irrespective of T2D-related characteristics and cardiovascular factors, our findings provide independent support for the association of CADM2 SNP rs17518584 with processing speed (and demonstrate association with additional cognitive phenotypes), among cognitively normal elderly individuals with T2D.

Young-Old City-Dwellers Outperform Village Counterparts in Attention and Verbal Control Tasks

Cognitive performance is dynamic and shaped by individual biological and environmental factors throughout life. In psychology, besides the effects of age, education, and other often studied factors, the complexity of the lived-in environment and urbanicity in that context are yet to be elucidated. In this observational cross-sectional study, we compare cognitive performance in standard neuropsychological tests in healthy older persons from three different types of settlements in the Czechia: the capital city of Prague, towns, and villages. The groups were equal in terms of the age-band (60–74 years), the distribution of gender, education, past and current leisure activities, and cognitive health status (MMSE score). The results showed that Prague citizens had consistently better performance in all verbal tests (for memory and verbal control, i.e., executive function) and attention than persons from other areas. The groups did not differ in timed visuo-graphomotor performance. The conclusion is that the complex environment of a city may promote, in the long-term, certain cognitive abilities, distinguishable even in a developed, culturally homogenous country. The implications are: (a) the description of samples used in normative studies should include information on the lived-in environment for the reference of researchers and clinicians; and (b) individual clinical assessment should reflect the role of the patient’s environment where appropriate. The exact mechanisms and causes of the differences need further investigation.

Distinct age-related associations for body mass index and cognition in cognitively healthy very old veterans

ABSTRACTAssociations between high body mass index (BMI) and subsequent cognitive decline, reported in elderly averaging below age 75, become less consistent at older ages. We compared the associations of BMI with cognition in moderately old (ages 75-84, N = 154) and oldest-old (85+, N = 93) samples. BMI and cognition were assessed cross-sectionally in cognitively intact elderly (mean age = 84.5, SD = 4.4) male veterans. Regression analyses of three cognitive domains - executive functions/language, attention, and memory-compared relationship with BMI between the moderately old and oldest-old. Higher BMI was associated with relatively poorer executive functions/language performance in the moderately old, while the opposite relationship, higher BMI associated with relatively better performance, was found in the oldest-old. Associations for the other two cognitive domains did not differ significantly between age groups. The reversal of association direction for executive functions/language performance with higher BMI is consistent with the protected survivor model. This model posits a minority subpopulation with a protective factor-genetic or otherwise-against both mortality and cognitive decline associated with risk factor status. The very old who remain cognitively intact despite the presence of risk factors are more likely to possess protection.

Huntington's disease: Brain imaging in Huntington's disease

Huntington's disease (HD) gene-carriers show prominent neuronal loss by end-stage disease, and the use of magnetic resonance imaging (MRI) has been increasingly used to quantify brain changes during earlier stages of the disease. MRI offers an in vivo method of measuring structural and functional brain change. The images collected via MRI are processed to measure different anatomical features, such as brain volume, macro- and microstructural changes within white matter and functional brain activity. Structural imaging has demonstrated significant volume loss across multiple white and gray matter regions in HD, particularly within subcortical structures. There also appears to be increasing disorganization of white matter tracts and between-region connectivity with increasing disease progression. Finally, functional changes are thought to represent changes in brain activity underlying compensatory mechanisms in HD. This chapter will provide an overview of the principles of MRI and practicalities associated with using MRI in HD studies, and summarize findings from MRI studies investigating brain structure and function in HD.

Confirmatory Factor Analysis of Neurocognitive Measures in Healthy Young Adults: The Relation of Executive Functions with Other Neurocognitive Functions

OBJECTIVE

The present study aimed to investigate the factor structure of a set of neurocognitive tests theoretically assessing executive functions (EF), verbal abilities (VA), and processing speed (PS). This study extended previous research by analyzing if each test is better explained by the specific factor to which it theoretically belongs or by a more general neurocognitive factor; and also by analyzing the relations between the neurocognitive factors.

METHODS

Using confirmatory factor analysis (CFA) we examined the factor structure of nine neurocognitive tests (EF: Working Memory, Tower, Divided Attention, Stroop, and Verbal Fluency tests; VA: Word List and Confrontation Naming tests; PS: Coding and Telephone Search tests) in a nonclinical sample (N = 90; 18-33 years old, 76 women). We tested five factor models of neurocognitive functioning: a one-factor model; two models with two-correlated factors; and two models with three-correlated factors.

RESULTS

A three-correlated-factor model, with EF, VA, and PS factors, was the most suitable for our neuropsychological data. The Verbal Fluency test was better explained by the VA factor rather than by the EF factor. The EF factor was correlated with the PS factor, but not with the VA factor.

CONCLUSIONS

Most of the neurocognitive measures used in the present study loaded in the expected factors (with the exception of the Verbal Fluency that was apparently more related to VA). EF and PS represent related but separable functions. Our results highlight the need for a careful interpretation of test scores since performance on one test usually requires multiple functions.

Neuropsychological Test Performance of Cognitively Healthy Centenarians: Normative Data From the Dutch 100-Plus Study

OBJECTIVES

The fraction of the population that reaches the age of 100 years is growing. At this age, dementia incidence is high and cognitive functioning is highly variable across individuals. Normative data for neuropsychological tests are lacking in centenarians, which hampers the ability to evaluate their cognitive functioning for both research and clinical practice. Here, we generated norms for neuropsychological tests in a sample of cognitively healthy centenarians while taking sensory impairments into account.

DESIGN

Cross-sectional cohort study.

SETTING

Centenarians who participate in the prospective 100-plus Study.

PARTICIPANTS

A total of 235 centenarians (71.5% female), who self-reported to be cognitively healthy, which was confirmed by an informant and a trained researcher.

MEASUREMENTS

We generated normative data for 15 cognitive tests, measuring global cognition (Mini-Mental State Examination [MMSE]), premorbid intelligence, attention, language, memory, executive function, and visuospatial function by multiple linear regressions and/or by reporting percentiles.

RESULTS

Normative data for global cognition resulted in a mean MMSE score of 25.6 ± 3.1 (range = 17-30; interquartile range = 24-28). Vision problems and fatigue often complicated the ability to complete tests, and these problems explained 41% and 22% of the missing test scores, respectively. In contrast, hearing problems (4%) and task incomprehension (6%) rarely complicated test performance. While educational level was associated with performance on the majority of the tests, sex and age were only weakly associated with test performance.

CONCLUSIONS

We generated normative data for 15 common neuropsychological tests in a large sample of cognitively healthy centenarians, while taking age-related sensory impairments into consideration. These normative data allow the detection of deficits across a wide range of cognitive domains. Our results suggest that, next to education level, vision ability and the level of fatigue should be taken into account when evaluating cognitive functioning in centenarians. J Am Geriatr Soc 67:759-767, 2019.

Deficit schizophrenia is a discrete diagnostic category defined by neuro-immune and neurocognitive features: results of supervised machine learning

Deficit schizophrenia is characterized by neurocognitive impairments and changes in the patterning of IgA/IgM responses to plasma tryptophan catabolites (TRYCATs). In the current study, supervised pattern recognition methods, including logistic regression analysis (LRA), Support Vector Machine (SVM), and Soft Independent Modeling of Class Analogy (SIMCA), were used to examine whether deficit schizophrenia is a discrete diagnostic class with respect to Consortium To Establish a Registry for Alzheimer's disease (CERAD) and Cambridge Neuropsychological Test Automated Battery (CANTAB) tests and IgA/IgM responses to noxious (NOX) and generally more protective (PRO) TRYCATs. We recruited patients with (n = 40) and without (n = 40) deficit schizophrenia and healthy volunteers (n = 40). The combined use of TRYCAT and CERAD features strongly segregates deficit from nondeficit schizophrenia and healthy controls. Three out of the top five most important features in LRA, SVM and SIMCA agreed, namely two different NOX/PRO TRYCAT ratios and false memory recall. SIMCA shows that deficit schizophrenia is significantly separated from nondeficit schizophrenia and controls with as top 6 features IgA responses to picolinic acid, IgM responses to 3-OH-kynurenine and kynurenic acid, and impairments in Word List Memory and Verbal Fluency Tests and Mini-Mental State Examination. Nevertheless, nondeficit schizophrenia was not significantly separated from controls. The results show that schizophrenia is not a unitary disease with mere continuous differences in severity of illness between apparent subtypes. Deficit schizophrenia is a qualitatively distinct class defined by neuroimmune (autoimmune responses to TRYCATs) and neurocognitive (episodic and semantic memory) features coupled or not with clinical (negative) symptoms.

CERAD Neuropsychological Battery-Arabic Version: Regression-Based and Stratified Normative Data and Effects of Demographic Variables on Cognitive Performance in Older Omanis

BACKGROUND AND OBJECTIVES

Normative data on cognitive performance for the Omani population are scarce. In this study, we tested a sample of older (≥50 years) community-dwelling Omanis on the Consortium to Establish a Registry for Alzheimer's Disease neuropsychological battery-Arabic version (CERAD-ArNB). We analyzed the participants' cognitive performance and how it was affected by their sex, age, and level of education.

METHODS

We enrolled 150 older Arabic-speaking Omanis from March 2014 to June 2015. Most of the participants were visitors to patients admitted to a tertiary referral center in the Sultanate of Oman. All participants underwent screening to ensure normal cognitive function before taking the CERAD-ArNB. We used multiple regression analysis and stratification according to demographic variables to illustrate the normative data.

RESULTS

A total of 125 participants, 65 men (52%) and 60 women (48%), met the inclusion criteria and completed the testing. Multiple regression and univariate analyses showed that although sex and age significantly affected cognitive performance on some CERAD-ArNB subtests, education level had by far the greatest effect.

CONCLUSIONS

Lower education level was associated with poorer CERAD-ArNB performance in a sample of cognitively normal Omanis aged 50 years and older. The normative data obtained from this study will help clinicians correctly interpret cognitive performance in the Omani elderly population, and probably in other, culturally similar Arabic-speaking communities.

In Schizophrenia, Depression, Anxiety, and Physiosomatic Symptoms Are Strongly Related to Psychotic Symptoms and Excitation, Impairments in Episodic Memory, and Increased Production of Neurotoxic Tryptophan Catabolites: a Multivariate and Machine Learning Study

The depression, anxiety and physiosomatic symptoms (DAPS) of schizophrenia are associated with negative symptoms and changes in tryptophan catabolite (TRYCAT) patterning. The aim of this study is to delineate the associations between DAPS and psychosis, hostility, excitation, and mannerism (PHEM) symptoms, cognitive tests as measured using the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) and IgA/IgM responses to TRYCATs. We included 40 healthy controls and 80 participants with schizophrenia. Depression and anxiety symptoms were measured with The Hamilton Depression (HAM-D) and Anxiety (HAM-A) Rating Scales, respectively. Physiosomatic symptoms were assessed with the Fibromyalgia and Chronic Fatigue Syndrome Rating Scale (FF). Negative symptoms as well as CERAD tests, including Verbal Fluency Test (VFT), Mini-Mental State Examination (MMSE), Word List Memory (WLM), and WL Delayed Recall were measured, while ratios of IgA responses to noxious/protective TRYCATs (IgA NOX_PRO) were computed. Schizophrenia symptoms consisted of two dimensions, a first comprising PHEM and negative symptoms, and a second DAPS symptoms. A large part of the variance in DAPS was explained by psychotic symptoms and WLM. Of the variance in HAM-D, 58.9% was explained by the regression on excitement, IgA NOX_PRO ratio, WLM, and VFT; 29.9% of the variance in HAM-A by psychotic symptoms and IgA NOX/PRO; and 45.5% of the variance in FF score by psychotic symptoms, IgA NOX/PRO, and WLM. Neural network modeling shows that PHEM, IgA NOX_PRO, WLM, and MMSE are the dominant variables predicting DAPS. DAPS appear to be driven by PHEM and negative symptoms coupled with impairments in episodic memory, especially false memory creation, while all symptom dimension and cognitive impairments may be driven by an increased production of noxious TRYCATs, including picolinic, quinolinic, and xanthurenic acid.

Depressive Symptoms Are Associated with Cognitive Function in the Elderly with Type 2 Diabetes

BACKGROUND

Type 2 diabetes (T2D) is a metabolic condition associated with poor clinical and cognitive outcomes including vascular disease, depressive symptoms, cognitive impairment, and dementia. In the general elderly population, depression has been consistently identified as a risk factor for cognitive impairment/decline. However, the association between depression and cognitive function in T2D has been understudied.

OBJECTIVE

We investigated the association between depression and cognitive function in a large sample of cognitively normal elderly with T2D.

METHODS

In this cross-sectional study, we examined 738 participants, aged 65-88 years old, enrolled in the Israel Diabetes and Cognitive Decline study. For each cognitive domain (Episodic Memory, Executive Function, Attention/Working Memory, Language/Semantic Categorization) and Overall Cognition, multiple linear regressions assessed its association with depression (score greater than 5 on the 15-item version of the Geriatric Depression Scale [GDS]), adjusting for age, sex, and education.

RESULTS

Depression (n = 66, 8.9%) was associated with worse performance on tasks of Executive Function (p = 0.004), Language/Semantic Categorization (p < 0.001), and Overall Cognition (p < 0.002), but not Episodic Memory (p = 0.643) or Attention/Working Memory (p = 0.488). Secondary analyses using GDS as a continuous variable did not substantially change the results. Adjusting also for a history of antidepressant medication use slightly weakened the findings.

CONCLUSION

Significant associations of depression with several cognitive domains and Overall Cognition even in cognitively normal elderly with T2D, suggest that depression may have a role in impaired cognitive function in T2D, which may be attenuated by antidepressants.

Changes in Tryptophan Catabolite (TRYCAT) Pathway Patterning Are Associated with Mild Impairments in Declarative Memory in Schizophrenia and Deficits in Semantic and Episodic Memory Coupled with Increased False-Memory Creation in Deficit Schizophrenia

Evidence indicates that schizophrenia and in particular negative symptoms and deficit schizophrenia are accompanied by neurocognitive impairments and changes in the patterning of the tryptophan catabolite (TRYCAT) pathway. This cross-sectional study was carried out to examine the associations between cognitive functions (as measured with Consortium to Establish a Registry for Alzheimer's disease (CERAD)) and TRYCAT pathway patterning in patients with (n = 40) and without (n = 40) deficit schizophrenia and normal controls (n = 40). Cognitive measures were assessed with the Verbal Fluency Test (VFT), Boston Naming Test (BNT), Mini-Mental State Examination (MMSE), Word List Memory (WLM), Constructional Praxis, Word List Recall (WLRecall), and Word List Recognition (WLRecognition), while TRYCAT measurements assessed the IgA/IgM responses to noxious TRYCATs, namely quinolinic acid (QA), 3-OH-kynurenine (3HK), picolinic acid (PA), and xanthurenic (XA) acid, and more protective (PRO) TRYCATs, including kynurenic acid (KA) and anthranilic acid (AA). IgA NOX/PRO, IgM KA/3HK, and IgA/IgM NOX/PRO ratios were computed. Schizophrenia was accompanied by lower VFT and WLM, while BNT (dysnomia) and MMSE are significantly lower in multiple- than first-episode schizophrenia. Deficit schizophrenia is strongly associated with worse outcomes on VFT, MMSE, WLM, WLRecall, WLRecognition, and delayed recall savings and increased false memories. Around 40-50% of the variance in negative symptoms' scores was explained by VFT, WLM, WLRecall, and MMSE. Increases in IgA NOX/PRO, IgM KA/3HK, and/or IgA/IgM NOX/PRO ratios were associated with impairments in VFT, BNT, MMSE, WLM, WLRecall, WLRecognition, and false-memory creation. In conclusion, nondeficit schizophrenia is accompanied by mild memory impairments, while disease progression is accompanied by broader cognitive impairments. Deficit schizophrenia and negative symptoms are strongly associated with deficits in working memory, delayed recall and recognition, and increased false-memory creation. These cognitive impairments and memory deficits are in part explained by increased production and/or attenuated regulation of TRYCATs with neurotoxic, excitotoxic, immune-inflammatory, oxidative, and nitrosative potential, which may contribute to neuroprogression.

Differences in performance in CAMCOG-R domains between old and oldest old patients with Alzheimer's disease

The purpose of this study is to evaluate the neuropsychological performance in a ≥90-year-old population with Alzheimer disease (AD) in comparison with younger elderly patients. We retrospectively studied all patients with AD attended in a specialized clinic between 1999 and 2011. Age, sex, educational level, and sensory loss data were collected. Neuropsychological evaluation included Mini-Mental State Examination and Global Deterioration Scale. We used the eight Cambridge Cognitive Assessment (CAMCOG-R) domains to evaluate and compare the neuropsychological performance in the younger than 90 years old (<90) and older than 90 years old (≥90) groups. We selected 2931 patients, 2897 <90 (98.83%) and 34 ≥90 years old (1.17%). The ≥90 group had significant lower punctuations in memory, praxis, and abstract thinking CAMOCG-R domains with 1.49, 0.75, and 0.58 less points, respectively, (p < 0.05). Neuropsychological characteristics of cognitive decline seem to be different in ≥90 compared to <90 years old patients. According to age, the biggest differences in the CAMCOG-R performance are in the memory, praxis, and abstract thinking domains.

Incidence of cognitively defined late-onset Alzheimer's dementia subgroups from a prospective cohort study

INTRODUCTION

There may be biologically relevant heterogeneity within typical late-onset Alzheimer's dementia.

METHODS

We analyzed cognitive data from people with incident late-onset Alzheimer's dementia from a prospective cohort study. We determined individual averages across memory, visuospatial functioning, language, and executive functioning. We identified domains with substantial impairments relative to that average. We compared demographic, neuropathology, and genetic findings across groups defined by relative impairments.

RESULTS

During 32,286 person-years of follow-up, 869 people developed Alzheimer's dementia. There were 393 (48%) with no domain with substantial relative impairments. Some participants had isolated relative impairments in memory (148, 18%), visuospatial functioning (117, 14%), language (71, 9%), and executive functioning (66, 8%). The group with isolated relative memory impairments had higher proportions with ≥ APOE ε4 allele, more extensive Alzheimer's-related neuropathology, and higher proportions with other Alzheimer's dementia genetic risk variants.

DISCUSSION

A cognitive subgrouping strategy may identify biologically distinct subsets of people with Alzheimer's dementia.

Peripheral Inflammatory Biomarkers and Cognitive Decline in Older Adults With and Without Alzheimer's Disease: A Systematic Review

Peripheral inflammatory biomarkers may play an important role in the cognitive decline of aging and incidence of Alzheimer's disease (AD); however, data from epidemiological studies present conflicting findings. The purpose of the current review was to systematically determine the current state of the science on the association between peripheral inflammatory biomarkers and cognitive decline. Articles published from January 1, 2006 to October 28, 2016 were searched using the Medline and Embase databases. Nine studies met inclusion criteria (two examined participants with AD dementia and seven examined participants without dementia). Although a wide range of peripheral inflammatory biomarkers was examined, C-reactive protein and interleukin 6 were the most studied. Findings show conflicting results for the association between peripheral inflammatory biomarkers and cognitive decline. Peripheral inflammation may harm and help the brain, and therefore, the challenge of modulating immunity will be to find ways of fine tuning inflammation to delay, prevent, or treat AD. [Journal of Gerontological Nursing, 43(12), 53-60.].

Population Normative Data for the CERAD Word List and Victoria Stroop Test in Younger- and Middle-Aged Adults: Cross-Sectional Analyses from the Framingham Heart Study

BACKGROUND/STUDY CONTEXT

To provide baseline normative data on tests of verbal memory and executive function for nondemented younger- and middle-aged adults.

METHODS

The Consortium to Establish a Registry for Alzheimer's Disease word list memory task (CERAD-WL) and Victoria Stroop Test (VST) were administered to 3362 Framingham Heart Study (FHS) volunteer participants aged 24-78 years. Analyses of the effects of age, gender, and education were conducted. Normative data on traditional measures and error responses are reported for each test.

RESULTS

Traditional measures were significantly associated with both age and education in this cohort. Error responses also evidenced significant age and education effects.

CONCLUSION

These data provide a normative comparison for assessment of verbal memory and executive functioning capabilities in younger- and middle-aged adults and may be utilized as a tool for preclinical studies of disease in this population.

Stress and gender effects on prefrontal cortex oxygenation levels assessed during single and dual-task walking conditions

The ability to walk is critical for functional independence and wellbeing. The pre-frontal cortex (PFC) plays a key role in cognitive control of locomotion, notably under attention-demanding conditions. Factors that influence brain responses to cognitive demands of locomotion, however, are poorly understood. Herein, we evaluated the individual and combined effects of gender and perceived stress on stride velocity and PFC Oxygenated Hemoglobin (HbO₂ ) assessed during single and dual-task walking conditions. The experimental paradigm included Normal Walk (NW); Cognitive Interference (Alpha); and Walk-While-Talk (WWT) tasks. An instrumented walkway was used to assess stride velocity in NW and WWT conditions. Functional Near-Infrared-Spectroscopy (fNIRS) was used to quantify PFC HbO₂ levels during NW, Alpha and WWT. Perceived task-related stress was evaluated with a single 11-point scale item. Participants were community residing older adults (age = 76.8 ± 6.7 years; %female = 56). Results revealed that higher perceived stress was associated with greater decline in stride velocity from single to dual-task conditions among men. Three-way interactions revealed that gender moderated the effect of perceived stress on changes in HbO₂ levels comparing WWT to NW and Alpha. Attenuation in the increase in HbO₂ levels, in high compared to low perceived stress levels, from the two single task conditions to WWT was observed only in men. Thus, older men may be more vulnerable to the effect of perceived stress on the change in PFC oxygenation levels across walking conditions that vary in terms of cognitive demands. These findings confer important implications for assessment and treatment of individuals at risk of mobility impairments.

Sex and gender differences in the treatment of Alzheimer's disease: A systematic review of randomized controlled trials

In recent years, epidemiological, clinical, and biological evidence has drawn the attention on the influence of sex and gender on Alzheimer's disease (AD). Nevertheless, not enough attention has been paid to their impact on treatment outcomes. The present study is aimed at systematically retrieve, review and discuss data coming from available randomized placebo-controlled trials (RCTs) on currently marketed treatments for AD (i.e., cholinesterase inhibitors [ChEIs] and memantine) in order to describe possible sex and gender differences in their efficacy, safety and tolerability. A systematic review of literature was performed. None of the retrieved studies reported data on the efficacy, safety and tolerability of considered medications separately in male and female patients with AD. We thus analyzed 48 excluded studies of potential interest, that is, almost all of the currently available trials on the four considered drugs. Nearly all the considered RCTs recruited a larger number of female participants to mirror the sexually unbalanced prevalence of AD. Only two studies took into account the potential influence of sex and gender on treatment efficacy, reporting no significant differences between men and women. None of the studies investigated potential sex and gender differences in the safety and tolerability of the four considered treatments. The existence of sex and gender differences in the efficacy and tolerability of ChEIs and memantine in AD has, to date, drawn limited to no attention. However, a considerable amount of data, with an adequate representativeness in terms of sex/gender distribution, seem to be already available for dedicated analyses on this topic. A greater effort should be made to collect and report data on those factors interacting with sex and gender that may significantly influence clinical manifestations, outcomes, and trajectories over time of AD patients.

Neuropsychological Test Performance in Cognitively Normal Spanish-speaking Nonagenarians with Little Education

To find associations of age, sex, and education with neuropsychological test performance in cognitively normal Spanish-speaking Costa Rican nonagenarians with little education; to provide norms; and to compare their performance with similar Puerto Ricans. For 95 Costa Ricans (90-102 years old, 0-6 years of education), multiple regression assessed associations with demographics of performance on six neuropsychological tests. Analyses of covariance compared them with 23 Puerto Ricans (90-99 years old). Younger age and being female-but not education-were associated with better performance on some neuropsychological tests, in particular episodic memory. The Puerto Ricans performed better on learning and memory tasks. In cognitively intact Spanish-speaking nonagenarians with little or no education, education did not affect test performance. Additional studies of the effect of education on cognitive performance are warranted in other samples with extremely low education or old age. National differences in performance highlight the importance of group-specific norms.

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

OBJECTIVE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Normative Data for the Cognitively Intact Oldest-Old: The Framingham Heart Study

BACKGROUND/STUDY CONTEXT: The number of individuals who reach extreme age is quickly increasing. Much of the current literature focuses on impaired cognition in extreme age, and debate continues regarding what constitutes "normal" cognition in extreme age. This study aimed to provide oldest-old normative data and to compare cognitive performances of cognitively intact elderly individuals from the Framingham Heart Study.

METHODS

A total of 1302 individuals aged 65+ years from the Framingham Heart Study were separated into 5-year age bands and compared on cognitive tests. Multivariate linear regression analyses were conducted, adjusting for gender, the Wide Range Achievement Test-Third Edition (WRAT-III) Reading score, and cohort. Analyses also included comparisons between 418 individuals aged 80+ and 884 individuals aged 65-79, and comparisons within oldest-old age bands.

RESULTS

Normative data for all participants are presented. Significant differences were found on most tests between age groups in the overall analysis between young-old and oldest-old, and analysis of oldest-old age bands also revealed select significant differences (all ps <.05).

CONCLUSION

As aging increases, significant cognitive differences and increased variability in performances are evident. These results support the use of age-appropriate normative data for oldest-old individuals.

Glutamate transporter splice variant expression in an enriched pyramidal cell population in schizophrenia

Dysregulation of the glutamate transporters EAAT1 and EAAT2 and their isoforms have been implicated in schizophrenia. EAAT1 and EAAT2 expression has been studied in different brain regions but the prevalence of astrocytic glutamate transporter expression masks the more subtle changes in excitatory amino acid transporters (EAATs) isoforms in neurons in the cortex. Using laser capture microdissection, pyramidal neurons were cut from the anterior cingulate cortex of postmortem schizophrenia (n = 20) and control (n = 20) subjects. The messenger RNA (mRNA) levels of EAAT1, EAAT2 and the splice variants EAAT1 exon9skipping, EAAT2 exon9skipping and EAAT2b were analyzed by real time PCR (RT-PCR) in an enriched population of neurons. Region-level expression of these transcripts was measured in postmortem schizophrenia (n = 25) and controls (n = 25). The relationship between selected EAAT polymorphisms and EAAT splice variant expression was also explored. Anterior cingulate cortex pyramidal cell expression of EAAT2b mRNA was increased (P < 0.001; 67%) in schizophrenia subjects compared with controls. There was no significant change in other EAAT variants. EAAT2 exon9skipping mRNA was increased (P < 0.05; 38%) at region level in the anterior cingulate cortex with no significant change in other EAAT variants at region level. EAAT2 single-nucleotide polymorphisms were significantly associated with changes in EAAT2 isoform expression. Haloperidol decanoate-treated animals, acting as controls for possible antipsychotic effects, did not have significantly altered neuronal EAAT2b mRNA levels. The novel finding that EAAT2b levels are increased in populations of anterior cingulate cortex pyramidal cells further demonstrates a role for neuronal glutamate transporter splice variant expression in schizophrenia.

Haptoglobin genotype modulates the relationships of glycaemic control with cognitive function in elderly individuals with type 2 diabetes

AIMS/HYPOTHESIS

The purpose of this study was to investigate whether the association of glycaemic control with cognitive function is modulated by the haptoglobin 1-1 (Hp 1-1) genotype in cognitively normal elderly individuals with type 2 diabetes.

METHODS

In this cross-sectional study, we examined 793 participants who were genotyped for Hp (80 Hp 1-1 carriers and 713 Hp 1-1 non-carriers) enrolled in the Israel Diabetes and Cognitive Decline (IDCD) study. Glycaemic control was operationally defined by HbA1c level. The outcome measures were performance in four cognitive domains (episodic memory, attention/working memory, language/semantic categorisation, executive function) and overall cognition, a composite of the domains. Effect sizes were obtained from hierarchical linear regression analyses for each outcome measure, controlling for demographics, type 2 diabetes-related characteristics, cardiovascular risk factors, and their interactions with Hp genotype.

RESULTS

Interaction analyses showed significantly stronger associations of HbA1c with poorer cognitive function among Hp 1-1 carriers than non-carriers; attention/working memory (p < 0.001) and overall cognition (p = 0.003). For these two cognitive domains, associations were significant for Hp 1-1 carriers despite the small sample size (p < 0.00001 and p = 0.001, respectively), but not for non-carriers.

CONCLUSIONS/INTERPRETATION

Our findings suggest that patients with type 2 diabetes and poor glycaemic control carrying the Hp 1-1 genotype may be at increased risk of cognitive impairment, particularly in the attention/working memory domain. The association of glycaemic control with this domain may indicate cerebrovascular mechanisms.