Nondemented Adults Research Articles

A-4 Amyloid Status Modifies the Association between Subjective Cognitive Decline and Brain MRI Metrics

Abstract Objective Subjective cognitive decline (SCD), a potential precursor to Alzheimer’s disease (ad), has been associated with increased neurodegeneration and cerebrovascular disease longitudinally. However, the impact of amyloid status, an early pathological marker of Alzheimer’s disease (ad) on these longitudinal associations is less clear. Here, we related baseline SCD to longitudinal biomarkers of brain health in the context of amyloid status. Method Participants included 139 non-demented older adults (72 ± 7 years) from the Vanderbilt Memory & Aging Project who completed a SCD questionnaire and fasting lumbar-puncture to quantify amyloid status (defined using published cutoffs of amyloid-beta42 levels) at baseline. 3 T brain-MRI to measure gray and white matter hyperintensity (WMH) volumes was collected at baseline, 18-months, 3-years, and 5-years. Linear mixed effects models assessed if baseline SCD X amyloid status was associated with longitudinal total and lobar grey and white matter volumes, covarying for baseline age, sex, race/ethnicity, education, diagnosis, mood, and apolipoprotein-Ee4 status. Models were also stratified by baseline amyloid status. Results Baseline SCD score and amyloid status interacted with total gray (p = 0.02) and WMH volume (p < 0.05). In stratified models, higher total SCD predicted increased inferior lateral ventricular volume (p < 0.001) among amyloid positive individuals. Conversely, in amyloid negative, greater baseline SCD was associated with increased WMH volumes globally (p = 0.03) and in the frontal and parietal lobes (p-values <0.035). Conclusion In the presence of amyloid, the presence of SCD is predictive of neurodegeneration in ad-specific regions. Conversely, SCD without amyloidosis may reflect a cerebrovascular disease, indicated by WMHs. Results highlight how amyloid status may help delineate etiologies of SCD.

Oral health and oral health care use among able-bodied adults enrolled in Medicaid in Kentucky after Medicaid expansion: A mixed methods study

BackgroundOral health care use remains low among adult Medicaid recipients, despite the Patient Protection and Affordable Care Act’s expansion increasing access to care in many states. It remains unclear the extent to which low use reflects either low demand for care or barriers to accessing care. The authors aimed to examine factors associated with low oral health care use among adults enrolled in Medicaid. MethodsThe authors conducted a survey from May through September 2018 among able-bodied (n = 9,363) Medicaid recipients who were aged 19 through 65 years and nondisabled childless adults in Kentucky. The survey included questions on perceived oral health care use. Semistructured interviews were also conducted from May through November 2018 among a subset of participants (n = 127). ResultsMore than one-third (37.8%) of respondents reported fair or poor oral health, compared with 26.2% who reported fair or poor physical health. Although 47.6% of respondents indicated needing oral health care in the past 6 months, only one-half of this group reported receiving all of the care they needed. Self-reported barriers included lack of coverage for needed services and lack of access to care (for example, low provider availability and transportation difficulties). ConclusionsLow rates of oral health care use can be attributed to a subset of the study population having low demand and another subset facing barriers to accessing care. Although Medicaid-covered services might be adequate for beneficiaries with good oral health, those with advanced dental diseases and a history of irregular care might benefit from coverage for more extensive restorative services. Practical ImplicationsThese results can inform dentists and policy makers about how to design effective interventions and policies to improve oral health care use and oral health outcomes.

Ambient air pollution exposures and functional decline in a sample of non-demented community-dwelling older adults in Northern Manhattan

BACKGROUND AND AIM: A growing body of evidence has linked air pollution exposures to indicators of unhealthy aging. The effects of air pollution on functional performance in older adults remain poorly understood. We investigated cross-sectional and longitudinal associations between air pollution exposures and functional performance. METHODS: From an available pool of 2182 participants enrolled in the Washington Heights-Inwood Aging Project from 1999-2002, 1884 individuals of Hispanic, Non-Hispanic White, or Non-Hispanic Black race-ethnicity who had valid addresses, no diagnosis of probable dementia at study intake, and were not missing data in the outcome measure of interest were selected. Inverse probability of censoring weighted linear mixed-effects models were used to investigate the associations between residential ambient air pollutant concentrations (fine particulate matter [PM2.5] and nitrogen dioxide [NO2]) at baseline and functional performance as measured by an extended Instrumental Activities of Daily living scale (IADL-x), adjusting for potential confounders. RESULTS:Participants were followed for a maximum of six study visits, with a median follow-up time of 4.28 years. Higher concentrations of pollutant exposures were associated with lower IADL-x scores at baseline and steeper rates of decline in IADL-x scores over time. In adjusted models, a one IQR increase in PM2.5 was associated with a 0.275 standard deviation SD (95 % CI: -0.356, -0.194) lower IADL-x score at baseline and an additional 0.031 SD (95% CI: -0.048, -0.013) decline per year of follow-up. A one IQR increase in NO2 was associated with a 0.133 SD (95 % CI: -0.180, -0.086) lower IADL-x score at baseline and an additional 0.035 SD (95% CI: -0.046, -0.024) decline per year of follow-up. CONCLUSIONS:These results contribute to the body of evidence on the deleterious effects of air pollution on healthy aging and point to opportunities for future research on potential pathways linking air pollution exposures to functional decline. KEYWORDS: air pollution, functional performance, aging.

Plasma neurofilament light as a potential biomarker for cognitive decline in a longitudinal study of middle-aged urban adults

Plasma neurofilament light (NfL) is a marker for neurodegenerative diseases. Few studies have examined the association of NfL with middle-aged changes in cognitive performance, and no studies have examined differential NfL effects by race. Using data from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study (n = 625, Agev1: 30–66 y, 41.6% male, 56.3% African American, 27.8% below poverty), we investigated the associations of initial NfL levels and annualized change with cognitive performance over time in global mental status, verbal and visual memory, fluency, attention, and executive function. We used ordinary least squares and mixed-effects regressions stratified by race, while exploring differential associations by age group, sex, and poverty status. Over a mean follow-up of 4.3 years, we found initial NfL level was associated with a faster decline on normalized mental status scores in Whites only and in those >50 years old. Annualized increase in NfL was associated with a greater decline in verbal fluency in men. In other exploratory analyses, annualized increase in NfL was associated with a slower decline in verbal memory among individuals living above poverty; in the older group (>50 years), first-visit NfL was linked with better performance at baseline in global mental status and verbal memory. In summary, first-visit NfL was primarily associated with the global mental status decline among Whites, while exhibiting inconsistent relationships in some exploratory analyses. Plasma NfL levels can be detected and quantified in non-demented middle-aged adults and changes can be analyzed over time. More longitudinal studies are needed to address the clinical utility of this biomarker for early cognitive defects.

Latent Profile Analysis of Cognition in a Non-Demented Diverse Cohort: A Focus on Modifiable Cardiovascular and Lifestyle Factors.

Cognitively-defined subgroups are well-documented within neurodegeneration. We examined such profiles in diverse non-demented older adults and considered how resulting subgroups relate to modifiable factors associated with neurodegeneration. 121 non-demented (MMSE = 28.62) diverse (46%non-Latino Black, 40%non-Latino White, 15%Latino) community-dwelling adults (age = 67.7 years) completed cognitive, cardiovascular, physical activity, and diet evaluations. Latent profile analyses (LPA) employed six cognitive scores (letter fluency, letter-number sequencing, confrontational naming, 'animal' fluency, list-learning delayed recall, and recognition discriminability) to characterize cognitively-defined subgroups. Differences between resulting subgroups on cardiovascular (composite scores of overall health; specific health components including fasting blood levels) and lifestyle (sedentary behavior; moderate-to-vigorous physical activity; Mediterranean diet consumption) factors were examined using ANCOVAs adjusting for relevant confounders. Based on sample means across cognitive scores, LPA resulted in the following cognitive subgroups: 1) high-average cognition, 55%non-Latino White and 64%female participants; 2) average cognition, 58%non-Latino Black and 68%male participants; 3) lower memory, 58%non-Latino Black participants; and 4) lower executive functioning, 70%Latinos. The high-average subgroup reported significantly higher Mediterranean diet consumption than the average subgroup (p = 0.001). The lower executive functioning group had higher fasting glucose and hemoglobin A1c than all other subgroups (p-values<0.001). LPA revealed two average subgroups reflecting level differences in cognition previously reported between non-Latino White and Black adults, and two lower cognition subgroups in domains similar to those documented in neurodegeneration. These subgroups, and their differences, suggest the importance of considering social determinants of health in cognitive aging and modifiable risk.

Midlife Vascular Factors and Prevalence of Mild Cognitive Impairment in Late-Life in Mexico.

To estimate the prevalence of mild cognitive impairment (MCI) and its subtypes and investigate the impact of midlife cardiovascular risk factors on late-life MCI among the aging Mexican population. Analyses included a sample of non-demented adults over the age of 55 living in both urban and rural areas of Mexico (N = 1807). MCI diagnosis was assigned based on a comprehensive cognitive assessment assessing the domains of memory, executive functioning, language, and visuospatial ability. The normative sample was selected by means of the robust norms approach. Cognitive impairment was defined by a 1.5-SD cut-off per cognitive domain using normative corrections for age, years of education, and sex. Risk factors included age, education, sex, rurality, depression, insurance status, workforce status, hypertension, diabetes, stroke, and heart disease. The prevalence of amnestic MCI was 5.9%. Other MCI subtypes ranged from 4.2% to 7.7%. MCI with and without memory impairment was associated with older age (OR = 1.01 [1.01, 1.05]; OR = 1.03 [1.01, 1.04], respectively) and residing in rural areas (OR = 1.49 [1.08, 2.06]; OR = 1.35 [1.03, 1.77], respectively). Depression (OR = 1.07 [1.02, 1.12]), diabetes (OR = 1.37 [1.03, 1.82]), and years of education (OR = 0.94 [0.91, 0.97]) were associated with MCI without memory impairment. Midlife CVD increased the odds of MCI in late-life (OR = 1.76 [1.19, 2.59], which was driven by both midlife hypertension and diabetes (OR = 1.70 [1.18, 2.44]; OR = 1.88 [1.19, 2.97], respectively). Older age, depression, low education, rurality, and midlife hypertension and diabetes were associated with higher risk of late-life MCI among older adults in Mexico. Our findings suggest that the causes of cognitive impairment are multifactorial and vary by MCI subtype.

Association of Osteoarthritis With Changes in Structural Neuroimaging Markers Over Time Among Non-demented Older Adults.

Objective: Although emerging evidence suggests that both osteoarthritis (OA) and brain atrophy (as assessed by structural neuroimaging markers) are associated with the risk of dementia, little is known about the association between OA and structural neuroimaging markers. This study aimed to examine the association of OA with changes in structural neuroimaging markers among non-demented older people.Methods: We examined the cross-sectional and longitudinal associations between OA and structural neuroimaging markers (hippocampal volume, entorhinal volume, ventricular volume, and volume of gray matter of the whole brain) among non-demented older people. We categorized our participants as those without OA (OA−) and those with OA (OA+). At baseline, we included 1,281 non-demented older adults, including 1,050 without OA and 231 with OA.Results: In the cross-sectional analysis, we did not observe any significant difference in structural neuroimaging markers between the two OA groups. In the longitudinal analysis, we found that compared to participants without OA, those with OA showed a steeper decline in volumes of the gray matter of the whole brain among non-demented older adults.Conclusions: OA was associated with a steeper decline in volumes of the gray matter of the whole brain over time among non-demented older people.

Comparison of conventional and actuarial neuropsychological criteria for mild cognitive impairment in a clinical setting

ABSTRACT Introduction Evidence-based practice in neuropsychology involves the use of validated tests, cutoff scores, and interpretive algorithms to identify clinically significant cognitive deficits. Recently, actuarial neuropsychological criteria (ANP) for identifying mild cognitive impairment were developed, demonstrating improved criterion validity and temporal stability compared to conventional criteria (CNP). However, benefits of the ANP criteria have not been investigated in non-research, clinical settings with varied etiologies, severities, and comorbidities. This study compared the utility of CNP and ANP criteria using data from a memory disorders clinic. Method Data from 500 non-demented older adults evaluated in a Veterans Affairs Medical Center memory disorders clinic were retrospectively analyzed. We applied CNP and ANP criteria to the Repeatable Battery for the Assessment of Neuropsychological Status, compared outcomes to consensus clinical diagnoses, and conducted cluster analyses of scores from each group. Results The majority (72%) of patients met both the CNP and ANP criteria and both approaches were susceptible to confounding factors such as invalid test data and mood disturbance. However, the CNP approach mislabeled impairment in more patients with non-cognitive disorders and intact cognition. Comparatively, the ANP approach misdiagnosed patients with depression at a third of the rate and those with no diagnosis at nearly half the rate of CNP. Cluster analyses revealed groups with: 1) minimal impairment, 2) amnestic impairment, and 3) multi-domain impairment. The ANP approach yielded subgroups with more distinct neuropsychological profiles. Conclusions We replicated previous findings that the CNP approach is over-inclusive, particularly for those determined to have no cognitive disorder by a consensus team. The ANP approach yielded fewer false positives and better diagnostic specificity than the CNP. Despite clear benefits of the ANP vs. CNP, there was substantial overlap in their performance in this heterogeneous sample. These findings highlight the critical role of clinical interpretation when wielding these empirically-derived tools.

Physical activity and cognitive and imaging biomarkers of Alzheimer's disease in down syndrome

Adults with Down syndrome (DS) are at risk for Alzheimer's disease. Despite sharing trisomy 21, however, there is variability in the age of disease onset. This variability may mean that other factors, such as lifestyle, influence cognitive aging and disease timing. The present study assessed the association between everyday life physical activity using an actigraph accelerometer and cognitive functioning and early Alzheimer's disease pathology via positron emission tomography amyloid-β and tau and diffusion tension imaging measures of white matter integrity in 61 non-demented adults with DS. Percent time in sedentary behavior and in moderate-to-vigorous activity were associated (negatively and positively, respectively) with cognitive functioning (r = -.472 to .572, p < 0.05). Neither sedentary behavior nor moderate-to-vigorous activity were associated with amyloid-β or tau, but both were associated with white matter integrity in the superior and inferior longitudinal fasciculus (Fractional Anisotropy: r = -.397 to -.419, p < 0.05; Mean Diffusivity: r = .400, p < 0.05). Longitudinal studies are needed to determine if physical activity promotes healthy aging in DS.

MEF2C Common Genetic Variation Is Associated With Different Aspects of Cognition in Non-Hispanic White and Caribbean Hispanic Non-demented Older Adults.

ObjectivesMyocyte Enhancer Factor 2C (MEF2C) is identified as a candidate gene contributing to the risk of developing Alzheimer’s disease. However, little is known about whether MEF2C plays a role in specific aspects of cognition among older adults. The current study investigated the association of common variants in the MEF2C gene with four cognitive domains including memory, visuospatial functioning, processing speed and language among non-demented individuals.MethodParticipants from two ethnic groups, Non-Hispanic White (NHW; n = 537) and Caribbean Hispanic (CH; n = 1,197) from the Washington Heights-Inwood Community Aging Project (WHICAP) study, were included. Genetic association analyses using WHICAP imputed genome-wide data (GWAS) were conducted for the various cognition domains.ResultsSingle nucleotide polymorphisms (SNP) variants in the MEF2C gene showed nominally significant associations in all cognitive domains but for different SNPs across both the ethnic groups. In NHW participants, the strongest associations were present for memory (rs302484), language (rs619584), processing speed (rs13159808), and visuospatial functioning (several SNPs). In CH, strongest associations were observed for memory (rs34822815), processing speed (rs304141), visuospatial functioning (rs10066711 and rs10038371), and language (rs304153).DiscussionMEF2C variant-cognitive associations shed light on an apparent role for MEF2C in both memory and non-memory aspects of cognition in individuals from NHW and CH ancestries. However, the little overlap in the specific SNP-cognition associations in CH versus NHW highlights the differences in genetic architectural variations among those from different ancestries that should be considered while studying the MEF2C gene.

How Does Dementia Begin to Manifest in Bipolar Disorder? A Description of Prodromal Clinical and Cognitive Changes.

Older adults with bipolar disorder (BD) have increased dementia risk, but signs of dementia are difficult to detect in the context of pre-existing deficits inherent to BD. To identify the emergence of indicators of early dementia in BD. One hundred and fifty-nine non-demented adults with BD from the National Alzheimer's Coordinating Center (NACC) data repository underwent annual neuropsychological assessment up to 14 years (54.0 months average follow-up). Cognitive performance was examined longitudinally with linear mixed-effects models, and yearly differences between incident dementia cases and controls were examined in the six years prior to diagnosis. Forty participants (25.2%) developed dementia over the follow-up period ('incident dementia cases'). Alzheimer's disease was the most common presumed etiology, though this was likely a result of sampling biases within NACC. Incident dementia cases showed declining trajectories in memory, language, and speeded attention two years prior to dementia onset. In a sample of BD patients enriched for Alzheimer's type dementia, prodromal dementia in BD can be detected up to two years before onset using the same cognitive tests used in psychiatrically-healthy older adults (i.e., measures of verbal recall and fluency). Cognition in the natural course of BD is generally stable, and impairment or marked decline on measures of verbal episodic memory or semantic retrieval may indicate an early neurodegenerative process.

Compensatory Strategies Due to Knee Flexion Constraint during Gait of Non-Disabled Adults

Constraining knee flexion of non-disabled individuals could further our understanding regarding the importance of knee joint during gait, which is a common disturbance in individuals with gait impairment. In this study we investigated whether a mechanical constraint of knee flexion in non-disabled adults would lead to compensatory strategies. Eleven non-disabled male adults walked without and with an orthosis that permitted full extension and limited knee flexion up to either 45° or 30°. We analyzed the temporal organization of lower limb kinematics and electromyograms of the rectus femoris, vastus medialis and lateralis, tibialis anterior, semitendinosus, biceps femoris, and gastrocnemius medialis and lateralis. Non-disabled adults compensated for the reduced knee flexion by increasing hip and ankle joint excursions and ankle flexor activation amplitude. Also, these adults shortened pre-swing and lengthened swing duration in the constrained limb and increased the activity of bifunctional hip extensor and knee flexor muscles in the constrained limb in relation to the unconstrained limb. The use of an orthosis that limited knee flexion in non-disabled adults leaded to compensatory strategies in the temporal organization of joint excursions and muscle activations in the constrained limb. The compensatory effects were correlated with the extent of knee flexion constraint.

Spontaneous Representations of Disability and Attitudes toward Inclusive Educational Practices: a Mixed Approach

The present study's primary aims were a) to explore non-disabled adults' spontaneous representation of disability and the specific associations related to adults and children with disabilities; to investigate participants' general perception of specific inclusive educational practices and the potential impact of contact with disabled individuals on children. We used a mixed (qualitative and quantitative) approach in a sample of 628 participants aged 18 to 82 (M=28.59, SD=11.50). Our results suggested that most explicit representations of disability were negatively valenced, i.e., people generally used pessimistic and detrimental related words. Psychomotor deficiencies comprised the most frequent disability category associated with disabled adults, while autism was the most frequent disability related to disabled children. Participants considered that the inclusion of physically disabled children (compared to children with intellectual disabilities) in public schools has a more positive effect on non-disabled children. The previous contact with a friend or a family member with a disability significantly and positively impacted the general attitude toward disability and inclusive educational practices. Results are discussed regarding their practical implications for the educational system and specific strategies related to inclusive public policies.

Cross-sectional and longitudinal interaction effects of physical activity and APOE-ε4 on white matter integrity in older adults: The MAPT study

Physical activity (PA) has been shown to modulate the detrimental effect of carrying the apolipoprotein-E epsilon 4 (APOE-ɛ4) allele on brain structure. However, the current literature mainly provides cross-sectional data, and longitudinal studies investigating the interaction between genotype and PA on white matter (WM) integrity are lacking. We investigated both the cross-sectional and the longitudinal interactive effects of APOE-ɛ4 and PA on WM integrity in older adults. Fractional anisotropy, as well as axial, radial, and mean diffusivity, extracted from brain diffusion tensor imaging (DTI) were used to assess WM integrity in non-demented older adults. They were categorized according to their APOE-ɛ4 status (carriers vs. non-carriers), and their level of total (TPA), moderate to vigorous (MVPA) and light (LPA) PA were assessed using a questionnaire. Mixed model regressions were performed to test the interactive effects of APOE-ɛ4 status and PA on WM integrity at baseline and over a 3-year follow-up. 190 subjects with a mean age 74.5 years (SD=3.9) were examined. Despite a lack of cross-sectional associations, sensitivity analyses revealed that, in the carrier group only, higher levels of LPA, but not MVPA, were mainly associated with higher axial and mean diffusivity values over time. This study partially confirms the previously reported interactive associations between PA, APOE-ɛ4 genotype and WM integrity, supporting the hypothesis that PA may protect against fiber loss in WM tracts containing crossing fibers. Future studies assessing sedentary behaviors in addition to PA could bring relevant contributions to the field. CLINICAL TRIAL REGISTRATION NUMBER FROM CLINICALTRIALS.GOV: NCT00672685.

Normative Study of the Block Design Test for Adults Aged 55 Years and Older in Korean Aging Population

ObjectiveThe Block Design Test (BDT) is known to be an effective measure in diagnosing age-related cognitive decline of visuospatial function. The goal of this study is to investigate the effects of age, education years, and gender on the performance of the BDT and to provide normative data in Korean community-dwelling participants who are 55 to 90 years old. MethodsThe participants were 432 non-demented adults aging from 55 to 90 years old. The BDT was administered to participants according to its manual. Multiple linear regressions and analyses of variance were conducted, including age, gender, and educations were used as covariates. ResultsAge, educational years, and gender were found to be significantly associated with performance on the BDT. As age increased, BDT performance decreased. Educational years were associated with BDT performance. Men showed higher performance (29.9±10.3) compare to women (26.1±8.7). The BDT is influenced by age, educational years, and gender. ConclusionUnlike the previous study, the current study shows that gender has a significant influence in visuospatial ability in the old population. Present normative data will be useful for clinicians in evaluating aging participants with cognitive impairment.

Association of plasma P-tau181 with memory decline in non-demented adults.

Alzheimer’s disease is the leading cause of dementia worldwide and is characterized by a long preclinical phase in which amyloid-β and tau accumulate in the absence of cognitive decline. In vivo biomarkers for Alzheimer’s disease are expensive, invasive and inaccessible, yet are critical for accurate disease diagnosis and patient management. Recent ultrasensitive methods to measure plasma phosphorylated tau 181 (p-tau181) display strong correlations with tau positron emission tomography, p-tau181 in CSF, and tau pathology at autopsy. The clinical utility of plasma-based p-tau181 biomarkers is unclear. In a longitudinal multicentre observational study, we assessed 1113 non-demented individuals (509 cognitively unimpaired elderly and 604 individuals with mild cognitive impairment) from the Alzheimer’s Disease Neuroimaging Initiative who underwent neuropsychological assessments and were evaluated for plasma p-tau181. The primary outcome was a memory composite z-score. Mixed-effect models assessed rates of memory decline in relation to baseline plasma p-tau181, and whether plasma p-tau181 significantly predicted memory decline beyond widely available clinical and genetic data (age, sex, years of education, cardiovascular and metabolic conditions, and APOEε4 status). Participants were followed for a median of 4.1 years. Baseline plasma p-tau181 was associated with lower baseline memory (β estimate: −0.49, standard error: 0.06, t-value: −7.97), as well as faster rates of memory decline (β estimate: −0.11, standard error: 0.01, t-value: −7.37). Moreover, the inclusion of plasma p-tau181 resulted in improved prediction of memory decline beyond clinical and genetic data (marginal R2 of 16.7–23%, χ2 = 100.81, P < 0.00001). Elevated baseline plasma p-tau181 was associated with higher rates of clinical progression to mild cognitive impairment (hazard ratio = 1.82, 95% confidence interval: 1.2–2.8) and from mild cognitive impairment to dementia (hazard ratio = 2.06, 95% confidence interval: 1.55–2.74). Our results suggest that in elderly individuals without dementia at baseline, plasma p-tau181 biomarkers were associated with greater memory decline and rates of clinical progression to dementia. Plasma p-tau181 improved prediction of memory decline above a model with currently available clinical and genetic data. While the clinical importance of this improvement in the prediction of memory decline is unknown, these results highlight the potential of plasma p-tau181 as a cost-effective and scalable Alzheimer’s disease biomarker.

Apathy and executive functioning among non-demented community-dwelling elderly individuals in an everyday environment: the mediating effect of impulsivity.

Apathy is common in normal ageing and widely recognized as a predictor of cognitive decline, especially in executive functions. Much less characterized than apathy in the elderly is impulsivity, which increases with ageing. It is also frequently described in comorbidity with apathy in various clinical populations, in whom it is associated with poorer executive functioning. In the present study, by capitalizing on a multidimensional approach, we explore the mediating role of facets of impulsivity on the bidirectional relationships between apathy dimensions and executive functioning in non-demented community-dwelling elderly individuals in daily life. A sample of non-demented community-dwelling older adults (n= 101) completed self-rated questionnaires. Apathy was measured by the Apathy Evaluation Scale; impulsivity was examined through the Urgency, Premeditation, Perseverance, Sensation Seeking, Positive Urgency (UPPS-P) Impulsive Behaviour Scale; and executive functioning in daily life was assessed by the Behaviour Rating Inventory of Executive Function-Adult (BRIEF-A). Two models positing mediation were tested using conditional process modelling. Hierarchical regressions controlling for depressive symptoms indicated that the cognitive apathy dimension was associated with the UPPS-P facets sensation seeking, lack of perseverance, and premeditation. Among the UPPS-P facets, lack of perseverance and negative urgency were found to contribute significantly to BRIEF-A Metacognitive index variance. Finally, in both models, lack of perseverance was found to totally mediate the relationship between cognitive apathy and the BRIEF-A Metacognitive index. These preliminary findings suggest that, in normal ageing, apathy may share an overlap with impulsivity, contradicting the notion they represent opposite ends of a single behavioural spectrum. Our results argue for bidirectional relationship between a specific apathy dimension (i.e. cognitive apathy) and executive functioning. Moreover, they shed new light on the underlying psychological process implicated (i.e. lack of perseverance) among older adults without dementia and represent an interesting prospect for psychological interventions.

Mild Behavioral Impairment Is Associated With Atrophy of Entorhinal Cortex and Hippocampus in a Memory Clinic Cohort.

ObjectivesMild behavioral impairment (MBI) is a syndrome describing late-onset persistent neuropsychiatric symptoms (NPS) in non-demented older adults. Few studies to date have investigated the associations of MBI with structural brain changes. Our aim was to explore structural correlates of NPS in a non-demented memory clinic sample using the Mild Behavioral Impairment Checklist (MBI-C) that has been developed to measure MBI.MethodsOne hundred sixteen non-demented older adults from the Czech Brain Aging Study with subjective cognitive concerns were classified as subjective cognitive decline (n = 37) or mild cognitive impairment (n = 79). Participants underwent neurological and neuropsychological examinations and brain magnetic resonance imaging (MRI) (1.5 T). The Czech version of the MBI-C was administered to participants’ informants. Five a priori selected brain regions were measured, namely, thicknesses of the orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and entorhinal cortex (ERC) and volume of the hippocampus (HV), and correlated with MBI-C total and domain scores.ResultsEntorhinal cortex was associated with MBI-C total score (rS = −0.368, p < 0.001) and with impulse dyscontrol score (rS = −0.284, p = 0.002). HV was associated with decreased motivation (rS = −0.248, p = 0.008) and impulse dyscontrol score (rS = −0.240, p = 0.011).ConclusionNeuropsychiatric symptoms, particularly in the MBI impulse dyscontrol and motivation domains, are associated with medial temporal lobe atrophy in a clinical cohort of non-demented older adults. This study supports earlier involvement of temporal rather than frontal regions in NPS manifestation. Since these regions are typically affected early in the course of Alzheimer’s disease (AD), the MBI-C may potentially help further identify individuals at-risk of developing AD dementia.

Neighborhood Socioeconomic Resources and Crime-Related Psychosocial Hazards, Stroke Risk, and Cognition in Older Adults.

Living in neighborhoods with lower incomes, lower education/occupational levels, and/or higher crime increases one’s risk of developing chronic health problems including cardiovascular disease risk factors and stroke. These cardiovascular health problems are known to contribute to cognitive decline and dementia. The purpose of this study was to determine the association of neighborhood socioeconomic resources and crime-related psychosocial hazards on stroke risk and cognition, hypothesizing that cardiovascular health would mediate any relationship between the neighborhood-level environment and cognition. The study evaluated 121 non-demented Chicago-area adults (~67 years; 40% non-Latino White) for cardiovascular health problems using the Framingham Stroke Risk Profile 10-year risk of stroke (FSRP-10). The cognitive domains that were tested included memory, executive functioning, and attention/information processing. Neighborhood socioeconomic resources were quantified at the census tract level (income, education, and occupation); crime-related psychosocial hazards were quantified at the point level. Structural equation modeling (SEM) did not show that the FSRP-10 mediated the relationship between neighborhood characteristics and domain-specific cognition. The SEM results did suggest that higher crime rates were associated with a higher FSRP-10 (β(105) = 2.38, p = 0.03) and that higher FSRP-10 is associated with reduced attention/information processing performance (β(105) = −0.04, p = 0.02) after accounting for neighborhood socioeconomic resources. Clinicians may wish to query not only individual but also neighborhood-level health when considering cognition.

Association of obstructive sleep apnea with cognitive decline and age among non-demented older adults

We aimed to investigate whether obstructive sleep apnea (OSA) status affects the relationship between cognitive decline and age among non-demented elderly people. A total of 1422 participants (493 normal cognition and 929 amnestic mild cognitive impairment) were obtained from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohort. Based on the self-reported medical history of OSA, participants were categorized into two groups (OSA- and OSA +). Multiple linear regression models were performed to assess the effect of the OSA * Age interaction on MMSE, ADAS-cog11 and RAVLT immediate recall in non-demented group and in APOE ε4 carriers/non-carriers adjusting for gender and educational attainment. In the present study, the OSA + group demonstrated significant cognitive decline versus the OSA- group. In addition, in APOE ε4- group, our findings showed a significant OSA * age interaction for ADAS-cog11 and RVALT immediate recall, but not MMSE. No significant interaction was observed in the APOE ε4+ individuals. In conclusion, our findings implicate that OSA status may affect the association of age with cognitive impairment among non-demented older people.