Performance on the Latin American version of the Face-Name Associative Memory Exam (LAS-FNAME) distinguishes individuals with Mild Cognitive Impairment from age-matched controls in a sample from Argentina

INTRODUCTION

The Latin American Spanish version of the Face-Name Associative Memory Exam (LAS-FNAME) has shown promise in identifying cognitive changes in those at risk for Alzheimer's disease (AD). However, its applicability for Mild Cognitive Impairment (MCI) detection in the Latin American population remains unexplored. This study aims to analyze the psychometric properties in terms of validity and reliability and diagnostic performance of the LAS-FNAME for the detection of memory disorders in patients with amnestic MCI (aMCI).

MATERIALS AND METHODS

The study included 31 participants with aMCI, diagnosed by a neurologist according to Petersen's criteria, and 19 healthy controls. Inclusion criteria for the aMCI group were to be 60 years of age or older, report cognitive complaints, have a memory test score (Craft Story 21) below a -1.5 z-score and have preserved functioning in activities of daily living. Participants completed LAS-FNAME and a comprehensive neuropsychological assessment.

RESULTS

LAS-FNAME showed the ability to discriminate against healthy controls from patients with aMCI (AUC= 75) in comparison with a gold-standard memory test (AUC = 69.1). LAS-FNAME also showed evidence of concurrent and divergent validity with a standard memory test (RAVLT) (r = 0.58, p < .001) and with an attention task (Digit Span) (r = -0.37, p = .06). Finally, the reliability index was very high (α = 0.88).

DISCUSSION

LAS-FNAME effectively distinguished aMCI patients from healthy controls, suggesting its potential for detecting early cognitive changes in Alzheimer's prodromal stages among Spanish speakers.

Associations of category fluency clustering performance with in vivo brain pathology in autosomal dominant Alzheimer's disease

OBJECTIVES

Alzheimer's disease (AD) is known to impact semantic access, which is frequently evaluated using the Category Fluency (Animals) test. Recent studies have suggested that in addition to overall category fluency scores (total number of words produced over time), poor clustering could signal AD-related cognitive difficulties. In this study, we examined the association between category fluency clustering performance (i.e., stating words sequentially that are all contained within a subcategory, such as domestic animals) and brain pathology in individuals with autosomal dominant Alzheimer's disease (ADAD).

METHODS

A total of 29 non-demented carriers of the Presenilin1 E280A ADAD mutation and 32 noncarrier family members completed the category fluency test (Animals) and the Mini-Mental State Examination (MMSE). The participants also underwent positron emission tomography (PET) scans to evaluate in vivo amyloid-beta in the neocortex and tau in medial temporal lobe regions. Differences between carriers and noncarriers on cognitive tests were assessed with Mann-Whitney tests; associations between cognitive test performance and brain pathology were assessed with Spearman correlations.

RESULTS

Animal fluency scores did not differ between carriers and noncarriers. Carriers, however, showed a stronger association between animal fluency clustering and in vivo AD brain pathology (neocortical amyloid and entorhinal tau) relative to noncarriers.

CONCLUSION

This study indicates that using category fluency clustering, but not total score, is related to AD pathophysiology in the preclinical and early stages of the disease.

The MAPP Room Memory Test: Examining Contextual Memory Using a Novel Computerized Test in Cognitively-Unimpaired Individuals with Autosomal Dominant Alzheimer's Disease

Contextual memory, the ability to remember spatial or temporal features related to an event, is affected in Alzheimer's disease (AD). There is a shortfall of tests that measure contextual memory. To evaluate visuospatial contextual memory, we developed a computerized cognitive test, the MAPP Room Memory Test, which requires participants to identify in which visual scene target items were previously presented. We hypothesized that cognitively-unimpaired carriers of an autosomal dominant AD mutation (Presenilin-1 E280A, n=15) would perform more poorly on this test than non-carrier family members (n=31). Compared to non-carriers, the carriers had significantly worse delayed room recognition. The results indicate that the MAPP Room Memory Test may be sensitive to subtle cognitive changes associated with risk of AD. Future studies with larger samples using the MAPP Room Memory Test and biomarkers are needed to examine whether this test may also be sensitive to the earliest pathological changes in preclinical AD.

H - 07 Associations among Cardiovascular Factors, Mood, and Cognition in Older Latinos: Preliminary Results from the Boston Latino Aging Study

OBJECTIVE

Cardiovascular risk factors and depression are prevalent in Latino populations and have been associated with an increased risk of cognitive decline and dementia. Adults with depressive symptoms also have an increased risk of cardiovascular disease. Understanding the link between these factors and how they impact dementia risk among Latino cohorts is critical for the development of preventative interventions. We examined the associations among cardiovascular risk factors, depression, and cognitive status in older Latinos living in Massachusetts.

METHOD

A total of 42 participants enrolled in the Boston Latino Aging Study (BLAST; n = 28, mean age = 65.36, SD = 7.35) and the Harvard Aging Brain Study Latino cohort (LHABS) (n = 14, mean age = 71.43, SD = 6.89) were included in the analyses. Participants completed a screening evaluation that included the Telephone Interview Cognitive Screen (TICS), the Geriatric Depression Scale (GDS), blood sampling to assess cholesterol, fasting glucose, and triglyceride levels, and systolic/diastolic blood pressure measurements. Spearman correlations were used to determine associations among cardiovascular risk factors, depression (GDS), and cognitive status (TICS).

RESULTS

We found that triglycerides (r = -0.424, p = 0.005) and glucose (r = -0.317, p = 0.041) were negatively correlated with TICS. Systolic blood pressure (r = 0.325, p = 0.036) and fasting glucose (r = 0.327, p = 0.034) were positively correlated with GDS scores.

CONCLUSION(S)

Preliminary results suggest a link between cardiovascular risk factors (e.g., elevated triglycerides and glucose) and worse cognitive status. Additionally, findings suggest cardiovascular risk factors may be related to depressive symptoms in older Latinos. Further work with larger samples of Latino participants is needed to confirm our findings and examine relevant associations with other risk factors.

A - 30 Risk Factors for Poor Sleep Quality and Subjective Cognitive Decline during the COVID-19 Pandemic in an Ethnoracially Diverse US Sample

OBJECTIVE

Poor sleep quality is associated with subjective cognitive decline (SCD), a risk factor for developing Alzheimer's disease and Mild Cognitive Impairment. These relationships are understudied in ethnoracially diverse groups. We examined associations between sociodemographic characteristics, sleep changes during the COVID-19 pandemic (i.e., increased problems/poorer quality), and SCD in ethnoracially diverse older individuals in the US.

METHOD

870 older adults (126 Latino, 74 Black, 33 Asian, and 637 White; Mage = 67.0 [7.6]) completed an online survey including sociodemographic information, the Everyday Cognition scale (ECog), which measures SCD, and a question inquiring about increased sleep problems/worsened sleep quality during the pandemic. Chi-square tests and analyses of variance assessed sociodemographic and SCD differences between groups. Regression and correlation analyses assessed relationships among sociodemographic factors, changes in sleep quality, and SCD.

RESULTS

White participants were older (p < 0.001), and White and Asian groups had higher education levels (p = 0.009) than Latinos. There were more female (p = 0.016) and middle-income (p = 0.019) White respondents. There were no group differences in ECog ratings (p = 0.143) or the proportion of respondents endorsing changes in sleep during the pandemic (p = 0.197). Changes in sleep were associated with greater SCD (β = 0.214, p < 0.001). Younger age (p < 0.001), female sex (p = 0.001), and lower income (p = 0.016) were significant predictors of changes in sleep.

CONCLUSIONS

Poorer sleep quality resulting from the COVID-19 pandemic was associated with SCD concerns. Notably, younger, female, and lower-income adults may have been at greater risk for increased sleep problems. Future work is needed to comprehensively examine sleep quality, SCD, and objective cognitive functioning in more representative samples.

Sex differences in blood biomarkers and cognitive performance in individuals with autosomal dominant Alzheimer's disease

INTRODUCTION

Plasma tau phosphorylated at threonine 217 (P-tau217) and neurofilament light (NfL) have emerged as markers of Alzheimer's disease (AD) pathology. Few studies have examined the role of sex in plasma biomarkers in sporadic AD, yielding mixed findings, and none in autosomal dominant AD.

METHODS

We examined the effects of sex and age on plasma P-tau217 and NfL, and their association with cognitive performance in a cross-sectional study of 621 Presenilin-1 E280A mutation carriers (PSEN1) and non-carriers.

RESULTS

As plasma P-tau217 levels increase, cognitively unimpaired female carriers showed better cognitive performance than cognitively unimpaired male carriers. Yet, as disease progresses, female carriers had a greater plasma NfL increase than male carriers. There were no sex differences in the association between age and plasma biomarkers among non-carriers.

DISCUSSION

Our findings suggest that, among PSEN1 mutation carriers, females had a greater rate of neurodegeneration than males, yet it did not predict cognitive performance.

HIGHLIGHTS

We examined sex differences in plasma P-tau217 and NfL in Presenilin-1 E280A (PSEN1) mutation carriers and non-carriers. Female carriers had a greater plasma NfL increase, but not P-tau217, than male carriers. As plasma P-tau217 levels increase, cognitively unimpaired female carriers showed better cognitive performance than cognitively unimpaired male carriers. The interaction effect of sex by plasma NfL levels did not predict cognition among carriers.

Effect of apolipoprotein genotype and educational attainment on cognitive function in autosomal dominant Alzheimer's disease

Autosomal dominant Alzheimer's disease (ADAD) is genetically determined, but variability in age of symptom onset suggests additional factors may influence cognitive trajectories. Although apolipoprotein E (APOE) genotype and educational attainment both influence dementia onset in sporadic AD, evidence for these effects in ADAD is limited. To investigate the effects of APOE and educational attainment on age-related cognitive trajectories in ADAD, we analyzed data from 675 Presenilin-1 E280A mutation carriers and 594 non-carriers. Here we show that age-related cognitive decline is accelerated in ADAD mutation carriers who also have an APOE e4 allele compared to those who do not and delayed in mutation carriers who also have an APOE e2 allele compared to those who do not. Educational attainment is protective and moderates the effect of APOE on cognition. Despite ADAD mutation carriers being genetically determined to develop dementia, age-related cognitive decline may be influenced by other genetic and environmental factors.

Plasma p-tau217 predicts in vivo brain pathology and cognition in autosomal dominant Alzheimer's disease

INTRODUCTION

Plasma-measured tau phosphorylated at threonine 217 (p-tau217) is a potential non-invasive biomarker of Alzheimer's disease (AD). We investigated whether plasma p-tau217 predicts subsequent cognition and positron emission tomography (PET) markers of pathology in autosomal dominant AD.

METHODS

We analyzed baseline levels of plasma p-tau217 and its associations with amyloid PET, tau PET, and word list delayed recall measured 7.61 years later in non-demented age- and education-matched presenilin-1 E280A carriers (n = 24) and non-carrier (n = 20) family members.

RESULTS

Carriers had higher plasma p-tau217 levels than non-carriers. Baseline plasma p-tau217 was associated with subsequent amyloid and tau PET pathology levels and cognitive function.

DISCUSSION

Our findings suggest that plasma p-tau217 predicts subsequent brain pathological burden and memory performance in presenilin-1 E280A carriers. These results provide support for plasma p-tau217 as a minimally invasive diagnostic and prognostic biomarker for AD, with potential utility in clinical practice and trials.

HIGHLIGHTS

Non-demented presenilin-1 E280A carriers have higher plasma tau phosphorylated at threonine 217 (p-tau217) than do age-matched non-carriers. Higher baseline p-tau217 is associated with greater future amyloid positron emission tomography (PET) pathology burden. Higher baseline p-tau217 is associated with greater future tau PET pathology burden. Higher baseline p-tau217 is associated with worse future memory performance.

Resilience to autosomal dominant Alzheimer's disease in a Reelin-COLBOS heterozygous man

We characterized the world's second case with ascertained extreme resilience to autosomal dominant Alzheimer's disease (ADAD). Side-by-side comparisons of this male case and the previously reported female case with ADAD homozygote for the APOE3 Christchurch (APOECh) variant allowed us to discern common features. The male remained cognitively intact until 67 years of age despite carrying a PSEN1-E280A mutation. Like the APOECh carrier, he had extremely elevated amyloid plaque burden and limited entorhinal Tau tangle burden. He did not carry the APOECh variant but was heterozygous for a rare variant in RELN (H3447R, termed COLBOS after the Colombia-Boston biomarker research study), a ligand that like apolipoprotein E binds to the VLDLr and APOEr2 receptors. RELN-COLBOS is a gain-of-function variant showing stronger ability to activate its canonical protein target Dab1 and reduce human Tau phosphorylation in a knockin mouse. A genetic variant in a case protected from ADAD suggests a role for RELN signaling in resilience to dementia.

Sex and gender considerations in dementia: a call for global research

Studies have identified sex and/or gender differences in Alzheimer’s disease, but few have examined other dementias. We highlight sex and gender differences in other dementias, discuss sociocultural factors and provide a framework for future global studies.

Associations Among Loneliness, Purpose in Life and Subjective Cognitive Decline in Ethnoracially Diverse Older Adults Living in the United States

Subjective cognitive decline (SCD), which precedes Mild Cognitive Impairment and dementia, may be affected by purpose in life (PiL) and loneliness in older adults. We investigated associations among PiL, loneliness, and SCD in US Latino (n = 126), Black (n = 74), Asian (n = 33), and White (n = 637) adults. Higher PiL predicted lower SCD in all groups (p-values < .012), except Black participants. Lower loneliness predicted lower SCD in Latino and White groups (p-values < .05), and PiL moderated this association in White adults. PiL and loneliness may play important roles in cognitive decline. Differential predictors of SCD suggest differential targets for preventing cognitive decline and dementia across ethnoracial groups.

Memory for Semantically Related Objects Differentiates Cognitively Unimpaired Autosomal Dominant Mutation Carriers from Non-Carrier Family Members

Early cognitive changes due to Alzheimer's disease (AD) include difficulties in semantic access and working memory. Using a computerized cognitive test developed by our group, called the Memory for Semantically Related Objects test (MESERO), we evaluated if cognitively unimpaired carriers of an autosomal dominant AD (ADAD) mutation performed worse on this test than non-carrier family members. 35 cognitively unimpaired ADAD mutation carriers and 26 non-carrier family members from a Colombian ADAD cohort took the MESERO on a laptop computer. Cognitively unimpaired ADAD carriers had significantly worse MESERO total scores than non-carrier family members, driven by worse performance in semantically-related object sets; group performances did not differ on semantically unrelated object sets. Findings suggest that MESERO performance may be sensitive to subtle cognitive changes associated with AD. Future MESERO research should examine performances between healthy older adults and people at risk for sporadic AD.

Waning locus coeruleus integrity precedes cortical tau accrual in preclinical autosomal dominant Alzheimer's disease

INTRODUCTION

Autopsy studies recognize the locus coeruleus (LC) as one of the first sites accumulating tau in Alzheimer's disease (AD). Recent AD work related in vivo LC magnetic resonance imaging (MRI) integrity to tau and cognitive decline; however, relationships of LC integrity to age, tau, and cognition in autosomal dominant AD (ADAD) remain unexplored.

METHODS

We associated LC integrity (3T-MRI) with estimated years of onset, cortical amyloid beta, regional tau (positron emission tomography [PET]) and memory (Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Word-List-Learning) among 27 carriers and 27 non-carriers of the presenilin-1 (PSEN1) E280A mutation. Longitudinal changes between LC integrity and tau were evaluated in 10 carriers.

RESULTS

LC integrity started to decline at age 32 in carriers, 12 years before clinical onset, and 20 years earlier than in sporadic AD. LC integrity was negatively associated with cortical tau, independent of amyloid beta, and predicted precuneus tau increases. LC integrity was positively associated with memory.

DISCUSSION

These findings support LC integrity as marker of disease progression in preclinical ADAD.

White matter hyperintensities are a prominent feature of autosomal dominant Alzheimer’s disease that emerge prior to dementia

Background

To promote the development of effective therapies, there is an important need to characterize the full spectrum of neuropathological changes associated with Alzheimer’s disease. In line with this need, this study examined white matter abnormalities in individuals with early-onset autosomal dominant Alzheimer’s disease, in relation to age and symptom severity.

Methods

This is a cross-sectional analysis of data collected in members of a large kindred with a PSEN1 E280A mutation. Participants were recruited between September 2011 and July 2012 from the Colombian Alzheimer’s Prevention Initiative registry. The studied cohort comprised 50 participants aged between 20 and 55 years, including 20 cognitively unimpaired mutation carriers, 9 cognitively impaired mutation carriers, and 21 non-carriers. Participants completed an MRI, a lumbar puncture for cerebrospinal fluid collection, a florbetapir PET scan, and neurological and neuropsychological examinations. The volume of white matter hyperintensities (WMH) was compared between cognitively unimpaired carriers, cognitively impaired carriers, and non-carriers. Relationships between WMH, age, and cognitive performance were further examined in mutation carriers.

Results

The mean (SD) age of participants was 35.8 (9.6) years and 64% were women. Cardiovascular risk factors were uncommon and did not differ across groups. Cognitively impaired carriers [median, 6.37; interquartile range (IQR), 9.15] had an increased volume of WMH compared to both cognitively unimpaired carriers [median, 0.85; IQR, 0.79] and non-carriers [median, 1.07; IQR, 0.71]. In mutation carriers, the volume of WMH strongly correlated with cognition and age, with evidence for an accelerated rate of changes after the age of 43 years, 1 year earlier than the estimated median age of symptom onset. In multivariable regression models including cortical amyloid retention, superior parietal lobe cortical thickness, and cerebrospinal fluid phospho-tau, the volume of WMH was the only biomarker independently and significantly contributing to the total explained variance in cognitive performance.

Conclusions

The volume of WMH is increased among individuals with symptomatic autosomal-dominant Alzheimer’s disease, begins to increase prior to clinical symptom onset, and is an independent determinant of cognitive performance in this group. These findings suggest that WMH are a key component of autosomal-dominant Alzheimer’s disease that is closely related to the progression of clinical symptoms.

Sex differences in cognitive resilience in preclinical autosomal-dominant Alzheimer's disease carriers and non-carriers: Baseline findings from the API ADAD Colombia Trial

INTRODUCTION

Females may have greater susceptibility to Alzheimer's disease (AD)-pathology. We examined the effect of sex on pathology, neurodegeneration, and memory in cognitively-unimpaired Presenilin-1 (PSEN1) E280A mutation carriers and non-carriers.

METHODS

We analyzed baseline data from 167 mutation carriers and 75 non-carriers (ages 30 to 53) from the Alzheimer's Prevention Initiative Autosomal Dominant AD Trial, including florbetapir- and fludeoxyglucose-PET, MRI based hippocampal volume and cognitive testing.

RESULTS

Females exhibited better delayed recall than males, controlling for age, precuneus glucose metabolism, and mutation status, although the effect was not significant among PSEN1 mutation carriers only. APOE ε4 did not modify the effect of sex on AD biomarkers and memory.

DISCUSSION

Our findings suggest that, among cognitively-unimpaired individuals at genetic risk for autosomal-dominant AD, females may have greater cognitive resilience to AD pathology and neurodegeneration than males. Further investigation of sex-specific differences in autosomal-dominant AD is key to elucidating mechanisms of AD risk and resilience.

Distinct tau neuropathology and cellular profiles of an APOE3 Christchurch homozygote protected against autosomal dominant Alzheimer's dementia

We describe in vivo follow-up PET imaging and postmortem findings from an autosomal dominant Alzheimer's disease (ADAD) PSEN1 E280A carrier who was also homozygous for the APOE3 Christchurch (APOE3ch) variant and was protected against Alzheimer's symptoms for almost three decades beyond the expected age of onset. We identified a distinct anatomical pattern of tau pathology with atypical accumulation in vivo and unusual postmortem regional distribution characterized by sparing in the frontal cortex and severe pathology in the occipital cortex. The frontal cortex and the hippocampus, less affected than the occipital cortex by tau pathology, contained Related Orphan Receptor B (RORB) positive neurons, homeostatic astrocytes and higher APOE expression. The occipital cortex, the only cortical region showing cerebral amyloid angiopathy (CAA), exhibited a distinctive chronic inflammatory microglial profile and lower APOE expression. Thus, the Christchurch variant may impact the distribution of tau pathology, modulate age at onset, severity, progression, and clinical presentation of ADAD, suggesting possible therapeutic strategies.

A cultural approach to dementia - insights from US Latino and other minoritized groups

Alzheimer disease and related dementias present considerable challenges to health-care and medical systems worldwide. In the USA, older Black and Latino individuals are more likely than older white individuals to have Alzheimer disease and related dementias. In this Perspective, we leverage our experience and expertise with older US Latino groups to review and discuss the need to integrate cultural factors into dementia research and care. We examine the importance of considering the effects of cultural factors on clinical presentation and diagnosis, dementia risk, clinical research and recruitment, and caregiving practices, with a focus on minoritized groups in the USA. We highlight critical gaps in the literature to stimulate future research aimed at improving the prevention and early detection of Alzheimer disease and related dementias and developing novel treatments and interventions across ethnoracially diverse populations. In addition, we briefly discuss some of our own initiatives to promote research and clinical care among Latino populations living in the USA.

Amyloid-β and tau pathologies relate to distinctive brain dysconnectomics in preclinical autosomal-dominant Alzheimer's disease

The human brain is composed of functional networks that have a modular topology, where brain regions are organized into communities that form internally dense (segregated) and externally sparse (integrated) subnetworks that underlie higher-order cognitive functioning. It is hypothesized that amyloid-β and tau pathology in preclinical Alzheimer’s disease (AD) spread through functional networks, disrupting neural communication that results in cognitive dysfunction. We used high-resolution (voxel-level) graph-based network analyses to test whether in vivo amyloid-β and tau burden was associated with the segregation and integration of brain functional connections, and episodic memory, in cognitively unimpaired Presenilin-1 E280A carriers who are expected to develop early-onset AD dementia in ∼13 y on average. Compared to noncarriers, mutation carriers exhibited less functional segregation and integration in posterior default-mode network (DMN) regions, particularly the precuneus, and in the retrospenial cortex, which has been shown to link medial temporal regions and cortical regions of the DMN. Mutation carriers also showed greater functional segregation and integration in regions connected to the salience network, including the striatum and thalamus. Greater tau burden was associated with lower segregated and integrated functional connectivity of DMN regions, particularly the precuneus and medial prefrontal cortex. In turn, greater tau pathology was related to higher segregated and integrated functional connectivity in the retrospenial cortex and the anterior cingulate cortex, a hub of the salience network. These findings enlighten our understanding of how AD-related pathology distinctly alters the brain’s functional architecture in the preclinical stage, possibly contributing to pathology propagation and ultimately resulting in dementia.

Olfactory Function and Markers of Brain Pathology in Non-Demented Individuals with Autosomal Dominant Alzheimer's Disease

BACKGROUND

Olfactory dysfunction is one of the earliest signs of Alzheimer's disease (AD), highlighting its potential use as a biomarker for early detection. It has also been linked to progression from mild cognitive impairment (MCI) to dementia.

OBJECTIVE

To study olfactory function and its associations with markers of AD brain pathology in non-demented mutation carriers of an autosomal dominant AD (ADAD) mutation and non-carrier family members.

METHODS

We analyzed cross-sectional data from 16 non-demented carriers of the Presenilin1 E280A ADAD mutation (mean age [SD]: 40.1 [5.3], and 19 non-carrier family members (mean age [SD]: 36.0 [5.5]) from Colombia, who completed olfactory and cognitive testing and underwent amyloid and tau positron emission tomography (PET) imaging.

RESULTS

Worse olfactory identification performance was associated with greater age in mutation carriers (r = -0.52 p = 0.037). In carriers, worse olfactory identification performance was related to worse MMSE scores (r = 0.55, p = 0.024) and CERAD delayed recall (r = 0.63, p = 0.007) and greater cortical amyloid-β (r = -0.53, p = 0.042) and tau pathology burden (entorhinal: r = -0.59, p = 0.016; inferior temporal: r = -0.52, p = 0.038).

CONCLUSION

Worse performance on olfactory identification tasks was associated with greater age, a proxy for disease progression in this genetically vulnerable ADAD cohort. In addition, this is the first study to report olfactory dysfunction in ADAD mutation carriers with diagnosis of MCI and its correlation with abnormal accumulation of tau pathology in the entorhinal region. Taken together, our findings suggest that olfactory dysfunction has promise as an early marker of brain pathology and future risk for dementia.

Neuroticism Is Associated with Tau Pathology in Cognitively Unimpaired Individuals with Autosomal Dominant Alzheimer's Disease

BACKGROUND

Greater neuroticism has been associated with higher risk for Alzheimer's disease (AD) dementia. However, the directionality of this association is unclear. We examined whether personality traits differ between cognitively-unimpaired carriers of autosomal-dominant AD (ADAD) and non-carriers, and are associated with in vivo AD pathology.

OBJECTIVE

To determine whether personality traits differ between cognitively unimpaired ADAD mutation carriers and non-carriers, and whether the traits are related to age and AD biomarkers.

METHODS

A total of 33 cognitively-unimpaired Presenilin-1 E280A mutation carriers and 41 non-carriers (ages 27-46) completed neuropsychological testing and the NEO Five-Factor Personality Inventory. A subsample (n = 46; 20 carriers) also underwent tau and amyloid PET imaging.

RESULTS

Carriers reported higher neuroticism relative to non-carriers, although this difference was not significant after controlling for sex. Neuroticism was positively correlated with entorhinal tau levels only in carriers, but not with amyloid levels.

CONCLUSION

The finding of higher neuroticism in carriers and the association of this trait with tau pathology in preclinical stages of AD highlights the importance of including personality measures in the evaluation of individuals at increased risk for cognitive impairment and dementia. Further research is needed to characterize the mechanisms of these relationships.

Sex Differences in Cognitive Abilities Among Children With the Autosomal Dominant Alzheimer Disease Presenilin 1 E280A Variant From a Colombian Cohort

IMPORTANCE

We previously reported that children with the autosomal dominant Alzheimer disease (ADAD) presenilin 1 (PSEN1) E280A variant had early life plasma biomarker findings consistent with amyloid β overproduction. However, the cognitive functioning of children with this variant has not been characterized vs those without the variant.

OBJECTIVE

To test whether cognitive functioning of children with and without the PSEN1 E280A variant in the same ADAD cohort differed by genetic status (ie, PSEN1 variant) and sex.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was conducted among 1354 children (including 265 children with the variant) aged 6 to 16 years recruited from the Alzheimer Prevention Initiative Colombia Registry. Participants from the city of Medellín and surrounding suburban areas traveled to the University of Antioquia to undergo all procedures. Participants were administered a Spanish version of the Wechsler Intelligence Scale for Children, Fourth Edition (WISC-IV) to measure general cognitive functioning. Data were analyzed from July through November 2020.

MAIN OUTCOMES AND MEASURES

Univariate general linear models were used to characterize differences on WISC-IV cognitive performance by genetic status, sex, and the interaction of genetic status with sex. Urbanity, socioeconomic status, and education were entered as covariates.

RESULTS

Among 1354 children with ADAD (695 [51.3%] girls; mean [SD] age, 11.64 [2.64] years), there were 265 children with the variant (19.6%) and 1089 children without the variant (80.4%). Children with and without the variant did not differ by demographic variables or performance on WISC-IV indices. Irrespective of genetic status, boys had statistically significantly decreased mean scores on indices for working memory (90.27 [95% CI, 89.21-91.34] vs 92.99 [95% CI, 91.98-93.99]; mean difference = -2.72; P < .001), perceptual reasoning (91.56 [95% CI, 90.47-92.65] vs. 93.27 [95% CI, 91.23-94.30]; mean difference = -1.71; P = .03), and verbal comprehension (88.69 [95% CI, 87.54-89.84] vs. 90.81 [95% CI, 89.73-91.90]; mean difference = -2.12; P = .009) compared with girls. In the interaction between sex and genetic status, boys with the variant had worse mean working memory index performance (88.78 [95% CI, 86.86-90.70]) than girls with the variant (93.75 [95% CI, 91.95-95.55]; mean difference = -4.97; P = .001), as well as boys (91.77 [95% CI, 90.85-92.70]; mean difference = -2.99; P = .04) and girls (92.22 [95% CI, 91.32-93.13]; mean difference = -3.44; P = .009) without the variant.

CONCLUSIONS AND RELEVANCE

This study found that boys with the PSEN1 variant had decreased working memory abilities compared with girls with the variant and boys and girls without the variant, suggesting a sex-specific genetic risk in early life cognitive performance among individuals with the PSEN1 variant. This increased risk of future cognitive difficulties among boys with the variant may have important downstream implications for learning and academic achievement and could be associated with sex differences seen in adulthood on episodic memory measures.

PET evidence of preclinical cerebellar amyloid plaque deposition in autosomal dominant Alzheimer's disease-causing Presenilin-1 E280A mutation carriers

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PET evidence of cerebellar Aβ deposition in unimpaired (CU) PSEN1 E280A kindred.

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Cerebellar Aβ PET SUVR began to distinguish CU carriers from non-carriers at age 34.

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Cortical and cerebellar Aβ PET SUVR are positively associated in CU carriers.

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Cerebellar florbetapir SUVR correlated with lower composite score in CU carriers.

Background

In contrast to sporadic Alzheimer’s disease, autosomal dominant Alzheimer’s disease (ADAD) is associated with greater neuropathological evidence of cerebellar amyloid plaque (Aβ) deposition. In this study, we used positron emission tomography (PET) measurements of fibrillar Aβ burden to characterize the presence and age at onset of cerebellar Aβ deposition in cognitively unimpaired (CU) Presenilin-1 (PSEN1) E280A mutation carriers from the world’s largest extended family with ADAD.

Methods

¹⁸F florbetapir and ¹¹C Pittsburgh compound B (PiB) PET data from two independent studies – API ADAD Colombia Trial (NCT01998841) and Colombia-Boston (COLBOS) longitudinal biomarker study were included. The tracers were selected independently by the respective sponsors prior to the start of each study and used exclusively throughout. Template-based cerebellar Aβ-SUVR (standard-uptake value ratios) using a known-to-be-spared pons reference region (cerebellar SUVR_pons), to a) compare 28–56-year-old CU carriers and non-carriers; b) estimate the age at which cerebellar SUVR_pons began to differ significantly in carrier and non-carrier groups; and c) characterize in carriers associations with age, cortical SUVR_pons, delayed recall memory, and API ADAD composite score.

Results

Florbetapir and PiB cerebellar SUVR_pons were significantly higher in carriers than non-carriers (p < 0.0001). Cerebellar SUVR_pons began to distinguish carriers from non-carriers at age 34, 10 years before the carriers’ estimated age at mild cognitive impairment onset. Florbetapir and PiB cerebellar SUVR_pons in carriers were positively correlated with age (r = 0.44 & 0.69, p < 0.001), cortical SUVR_pons (r = 0.55 & 0.69, p < 0.001), and negatively correlated with delayed recall memory (r = −0.21 & −0.50, p < 0.05, unadjusted for cortical SUVR_pons) and API ADAD composite (r = −0.25, p < 0.01, unadjusted for cortical SUVR_pons in florbetapir API ADAD cohort).

Conclusion

This PET study provides evidence of cerebellar Aβ plaque deposition in CU carriers starting about a decade before the clinical onset of ADAD. Additional studies are needed to clarify the impact of using a cerebellar versus pons reference region on the power to detect and track ADAD changes, even in preclinical stages of this disorder.

Associations between subregional thalamic volume and brain pathology in autosomal dominant Alzheimer's disease

Histopathological reports suggest that subregions of the thalamus, which regulates multiple physiological and cognitive processes, are not uniformly affected by Alzheimer's disease. Despite this, structural neuroimaging studies often consider the thalamus as a single region. Identification of in vivo Alzheimer's-dependent volumetric changes in thalamic subregions may aid the characterization of early nuclei-specific neurodegeneration in Alzheimer's disease. Here, we leveraged access to the largest single-mutation cohort of autosomal-dominant Alzheimer's disease to test whether cross-sectional abnormalities in subregional thalamic volumes are evident in non-demented mutation carriers (n = 31), compared to non-carriers (n = 36), and whether subregional thalamic volume is associated with age, markers of brain pathology and cognitive performance. Using automatic parcellation we examined the thalamus in six subregions (anterior, lateral, ventral, intralaminar, medial, and posterior) and their relation to age and brain pathology (amyloid and tau), as measured by PET imaging. No between-group differences were observed in the volume of the thalamic subregions. In carriers, lower volume in the medial subregion was related to increased cortical amyloid and entorhinal tau burden. These findings suggest that thalamic Alzheimer's-related volumetric reductions are not uniform even in preclinical and prodromal stages of autosomal-dominant Alzheimer's disease and therefore, this structure should not be considered as a single, unitary structure in Alzheimer's disease research.

Associations between plasma neurofilament light, in vivo brain pathology, and cognition in non-demented individuals with autosomal-dominant Alzheimer's disease

BACKGROUND

Neurofilament light (NfL) is a promising biomarker of early neurodegeneration in Alzheimer's disease (AD). We examined whether plasma NfL was associated with in vivo amyloid beta and tau, and cognitive performance in non-demented presenilin-1 (PSEN1) E280A mutation carriers.

METHODS

Twenty-five mutation carriers and 19 non-carriers (age range: 28 to 49 years) were included in this study. Participants underwent 11C Pittsburgh compound B (PiB)-PET (positron emission tomography), flortaucipir-PET, blood sampling, and cognitive testing.

RESULTS

Mutation carriers exhibited higher plasma NfL levels than non-carriers. In carriers, higher NfL levels were related to greater regional tau burden and worse cognition, but not amyloid beta load. When we adjusted for age, a proxy of disease progression, elevated plasma NfL levels were only correlated with worse memory recall.

CONCLUSIONS

Findings support an association between plasma NfL, cognition, and tau pathology in non-demented individuals at genetic risk for developing AD dementia. Plasma NfL may be useful for selecting individuals at increased risk and tracking disease progression in AD.

The impact of COVID-19 on the well-being and cognition of older adults living in the United States and Latin America

BACKGROUND

In the COVID-19 pandemic, older adults from vulnerable ethnoracial groups are at high risk of infection, hospitalization, and death. We aimed to explore the pandemic's impact on the well-being and cognition of older adults living in the United States (US), Argentina, Chile, Mexico, and Peru.

METHODS

1,608 (646 White, 852 Latino, 77 Black, 33 Asian; 72% female) individuals from the US and four Latin American countries aged ≥ 55 years completed an online survey regarding well-being and cognition during the pandemic between May and September 2020. Outcome variables (pandemic impact, discrimination, loneliness, purpose of life, subjective cognitive concerns) were compared across four US ethnoracial groups and older adults living in Argentina, Chile, Mexico, and Peru.

FINDINGS

Mean age for all participants was 66.7 (SD = 7.7) years and mean education was 15.4 (SD = 2.7) years. Compared to Whites, Latinos living in the US reported greater economic impact (p < .001, ηp 2  = 0.031); while Blacks reported experiencing discrimination more often (p < .001, ηp 2  = 0.050). Blacks and Latinos reported more positive coping (p < .001, ηp 2  = 0.040). Compared to Latinos living in the US, Latinos in Chile, Mexico, and Peru reported greater pandemic impact, Latinos in Mexico and Peru reported more positive coping, Latinos in Argentina, Mexico, and Peru had greater economic impact, and Latinos in Argentina, Chile, and Peru reported less discrimination.

INTERPRETATION

The COVID-19 pandemic has differentially impacted the well-being of older ethnically diverse individuals in the US and Latin America. Future studies should examine how mediators like income and coping skills modify the pandemic's impact.

FUNDING

Massachusetts General Hospital Department of Psychiatry.

Longitudinal amyloid and tau accumulation in autosomal dominant Alzheimer's disease: findings from the Colombia-Boston (COLBOS) biomarker study

BACKGROUND

Neuroimaging studies of autosomal dominant Alzheimer's disease (ADAD) enable characterization of the trajectories of cerebral amyloid-β (Aβ) and tau accumulation in the decades prior to clinical symptom onset. Longitudinal rates of regional tau accumulation measured with positron emission tomography (PET) and their relationship with other biomarker and cognitive changes remain to be fully characterized in ADAD.

METHODS

Fourteen ADAD mutation carriers (Presenilin-1 E280A) and 15 age-matched non-carriers from the Colombian kindred underwent 2-3 sessions of Aβ (11C-Pittsburgh compound B) and tau (18F-flortaucipir) PET, structural magnetic resonance imaging, and neuropsychological evaluation over a 2-4-year follow-up period. Annualized rates of change for imaging and cognitive variables were compared between carriers and non-carriers, and relationships among baseline measurements and rates of change were assessed within carriers.

RESULTS

Longitudinal measurements were consistent with a sequence of ADAD-related changes beginning with Aβ accumulation (16 years prior to expected symptom onset, EYO), followed by entorhinal cortex (EC) tau (9 EYO), neocortical tau (6 EYO), hippocampal atrophy (6 EYO), and cognitive decline (4 EYO). Rates of tau accumulation among carriers were most rapid in parietal neocortex (~ 9%/year). EC tau PET signal at baseline was a significant predictor of subsequent neocortical tau accumulation and cognitive decline within carriers.

CONCLUSIONS

Our results are consistent with the sequence of biological changes in ADAD implied by cross-sectional studies and highlight the importance of EC tau as an early biomarker and a potential link between Aβ burden and neocortical tau accumulation in ADAD.

Association Between Visual Memory and In Vivo Amyloid and Tau Pathology in Preclinical Autosomal Dominant Alzheimer's Disease

OBJECTIVE

Visual memory (ViM) declines early in Alzheimer's disease (AD). However, it is unclear whether ViM impairment is evident in the preclinical stage and relates to markers of AD pathology. We examined the relationship between ViM performance and in vivo markers of brain pathology in individuals with autosomal dominant AD (ADAD).

METHODS

Forty-five cognitively unimpaired individuals from a Colombian kindred with the Presenilin 1 (PSEN1) E280A ADAD mutation (19 carriers and 26 noncarriers) completed the Rey-Osterrieth Complex Figure immediate recall test, a measure of ViM. Cortical amyloid burden and regional tau deposition in the entorhinal cortex (EC) and inferior temporal cortex (IT) were measured using 11C-Pittsburgh compound B positron emission tomography (PET) and 11F-flortaucipir PET, respectively.

RESULTS

Cognitively unimpaired carriers and noncarriers did not differ on ViM performance. Compared to noncarriers, carriers had higher levels of cortical amyloid and regional tau in both the EC and IT. In cognitively unimpaired carriers, greater cortical amyloid burden, higher levels of regional tau, and greater age were associated with worse ViM performance. Only a moderate correlation between regional tau and ViM performance remained after adjusting for verbal memory scores. None of these correlations were observed in noncarriers.

CONCLUSIONS

Results suggest that AD pathology and greater age are associated with worse ViM performance in ADAD before the onset of clinical symptoms. Further investigation with larger samples and longitudinal follow-up is needed to examine the utility of ViM measures for identifying individuals at high risk of developing dementia later in life.

The Latin American Spanish version of the Face-Name Associative Memory Exam is sensitive to cognitive and pathological changes in preclinical autosomal dominant Alzheimer's disease

BACKGROUND

To determine whether performance on the Latin American Spanish version of the Face-Name Associative Memory Exam (LAS-FNAME) can differentiate between cognitively intact carriers of an autosomal dominant Alzheimer's disease mutation (E280A) in Presenilin-1, who are genetically determined to develop early-onset dementia, from matched non-carriers. We also sought to examine whether LAS-FNAME performance is associated with amyloid-β and regional tau burden in mutation carriers.

METHODS

A total of 35 cognitively intact mutation carriers (age range 26-41), 19 symptomatic carriers, and 48 matched non-carriers (age range 27-44) completed a neuropsychological assessment including the LAS-FNAME. A subset of participants (31 carriers [12 symptomatic] and 35 non-carriers) traveled from Colombia to Boston to undergo positron emission tomography (PET) using Pittsburgh compound B to measure mean cortical amyloid-β and flortaucipir for regional tau. ANOVA analyses and Spearman correlations were used to examine group differences and relationships among LAS-FNAME performance and amyloid-β and tau accumulation.

RESULTS

Compared to non-carriers, cognitively intact mutation carriers had lower scores on the LAS-FNAME Total Scores (p = .040). Across all carriers (including symptomatic carriers), higher levels of amyloid-β (r = - .436, p = .018) and regional tau in the entorhinal (r = - .394, p = .031) and inferior temporal cortex (r = - .563, p = .001) were associated with lower LAS-FNAME Total Scores.

CONCLUSIONS

Performance on the LAS-FNAME differentiated between cognitively intact mutation carriers from non-carriers and was associated with greater amyloid and tau burden when examining all carriers. Findings suggest that the LAS-FNAME is sensitive to early clinical and pathological changes and can potentially help track disease progression in Spanish-speaking individuals.

A-05 The Latin American Spanish Version of the Face-Name Associative Memory Exam is Sensitive to Cognitive and Pathological Changes in Preclinical Autosomal Dominant Alzheimer’s Disease

Objective

To determine whether performance on the Latin American Spanish version of the Face-Name Associative Memory Exam (LAS-FNAME) can differentiate between cognitively intact carriers of an autosomal dominant Alzheimer’s disease mutation (E280A) in Presenilin-1, who are destined to develop early-onset dementia, from matched non-carriers. We also sought to examine whether LAS-FNAME performance is associated with amyloid-β and regional tau burden in mutation carriers.

Methods

35 cognitively intact mutation carriers (age range 26–41), 48 matched non-carriers (aged 27 to 44), and 19 symptomatic carriers (13 with subjective cognitive concerns, 6 with mild cognitive impairment [MCI]) completed the LAS-FNAME. A subset of participants (31 carriers [12 symptomatic] and 35 non-carriers) traveled from Colombia to Boston to undergo positron emission tomography (PET) using Pittsburgh compound B to measure mean cortical amyloid-β and Flortaucipir for regional tau tangles. ANOVA analyses and Spearman correlations were used to examine group differences and relationships among LAS-FNAME performance, Aβ and tau accumulation.

Results

Compared to non-carriers, cognitively intact carriers had lower scores on the LAS-FNAME total scores (p = .040). Across all carriers (including symptomatic carriers), higher levels of amyloid-β (r = −.436, p = .018) and regional tau in the entorhinal (r = −.394, p = .031) and inferior temporal cortex (r = −.563, p = .001) were associated with lower LAS-FNAME total scores (see Figure).

Conclusions

Performance on the LAS-FNAME differentiated between cognitively intact mutation carriers from non-carriers, and was associated with greater amyloid and tau burden when examining all carriers. Findings suggest that the LAS-FNAME is sensitive to early clinical and pathological changes and can potentially help track disease progression in Spanish-speaking individuals.

Associative memory and in vivo brain pathology in asymptomatic presenilin-1 E280A carriers

OBJECTIVE

To determine whether performance on the Free and Cued Selective Reminding Test (FCSRT) is associated with PET in vivo markers of brain pathology and whether it can distinguish those who will develop dementia later in life due to autosomal-dominant Alzheimer disease (AD) from age-matched controls.

METHODS

Twenty-four cognitively unimpaired Presenilin-1 E280A carriers (mean age 36 years) and 28 noncarriers (mean age 37 years) underwent Pittsburg compound B-PET (amyloid), flortaucipir-PET (tau), and cognitive testing, including the FCSRT (immediate and delayed free and cued recall scores). Linear regressions were used to examine the relationships among FCSRT scores, age, mean cortical amyloid, and regional tau burden.

RESULTS

Free and total recall scores did not differ between cognitively unimpaired mutation carriers and noncarriers. Greater age predicted lower free recall and delayed free and total recall scores in carriers. In cognitively impaired carriers, delayed free recall predicted greater amyloid burden and entorhinal tau, while worse immediate free recall scores predicted greater tau in the inferior temporal and entorhinal cortices. In turn, in all carriers, lower free and total recall scores predicted greater amyloid and regional tau pathology.

CONCLUSIONS

FCSRT scores were associated with in vivo markers of AD-related pathology in cognitively unimpaired individuals genetically determined to develop dementia. Difficulties on free recall, particularly delayed recall, were evident earlier in the disease trajectory, while difficulties on cued recall were seen only as carriers neared the onset of dementia, consistent with the pathologic progression of the disease. Findings suggest that the FCSRT can be a useful measure to track disease progression in AD.

Plasma neurofilament light chain in the presenilin 1 E280A autosomal dominant Alzheimer's disease kindred: a cross-sectional and longitudinal cohort study

BACKGROUND

Neurofilament light chain (NfL) is a promising biomarker of active axonal injury and neuronal degeneration. We aimed to characterise cross-sectional and longitudinal plasma NfL measurements and determine the age at which NfL concentrations begin to differentiate between carriers of the presenilin 1 (PSEN1) E280A (Glu280Ala) mutation and age-matched non-carriers from the Colombian autosomal dominant Alzheimer's disease kindred.

METHODS

In this cross-sectional and longitudinal cohort study, members of the familial Alzheimer's disease Colombian kindred aged 8-75 years with no other neurological or health conditions were recruited from the Alzheimer's Prevention Initiative Registry at the University of Antioquia (Medellín, Colombia) between Aug 1, 1995, and Dec 15, 2018. We used a single molecule array immunoassay and log-transformed data to examine the relationship between plasma NfL concentrations and age, and establish the earliest age at which NfL concentrations begin to diverge between mutation carriers and non-carriers.

FINDINGS

We enrolled a cohort of 1070 PSEN1 E280A mutation carriers and 1074 non-carriers with baseline assessments; of these participants, longitudinal measures (with a mean follow-up of 6 years) were available for 242 mutation carriers and 262 non-carriers. Plasma NfL measurements increased with age in both groups (p<0·0001), and began to differentiate carriers from non-carriers when aged 22 years (22 years before the estimated median age at mild cognitive impairment onset of 44 years), although the ability of plasma NfL to discriminate between carriers and non-carriers only reached high sensitivity close to the age of clinical onset.

INTERPRETATION

Our findings further support the promise of plasma NfL as a biomarker of active neurodegeneration in the detection and tracking of Alzheimer's disease and the evaluation of disease-modifying therapies.

FUNDING

National Institute on Aging, National Institute of Neurological Disorders and Stroke, Banner Alzheimer's Foundation, COLCIENCIAS, the Torsten Söderberg Foundation, the Swedish Research Council, the Swedish Alzheimer Foundation, the Swedish Brain Foundation, and the Swedish state under the ALF-agreement.

Examining Sex Differences in Markers of Cognition and Neurodegeneration in Autosomal Dominant Alzheimer's Disease: Preliminary Findings from the Colombian Alzheimer's Prevention Initiative Biomarker Study

BACKGROUND

Growing evidence suggests that there may be a sex-specific biological risk for Alzheimer's disease (AD). Individuals with autosomal dominant AD due to a mutation (E280A) in Presenilin-1 (PSEN1) are genetically determined to develop early-onset dementia and thus, have few age-related risk factors for AD that are known to vary by sex (i.e., cardiovascular disease, menopause, life expectancy).

OBJECTIVE

Investigate sex differences in markers of cognition and neurodegeneration in autosomal dominant AD.

METHODS

We conducted a retrospective study in 19 cognitively-unimpaired PSEN1 mutation carriers (age range 20-44; 11 females), 11 symptomatic carriers (age range 42-56; 8 females), and 23 matched non-carriers family members (age range 20-50; 13 females). We examined hippocampal volume ratio, CERAD Total Score, and CERAD Word List (i.e., Learning, Delayed Recall, and Recognition). Mann-Whitney U tests, Spearman correlations and regression models were conducted.

RESULTS

There were no differential associations between age, CERAD Total Score, CERAD Word List-Learning, Delayed Recall, Recognition, and hippocampal volume ratio in male and female carriers and non-carriers. Cognitively-unimpaired female carriers showed better CERAD Total scores and CERAD Word List-Learning than cognitively-unimpaired male carriers, despite having similar hippocampal volume ratios. The interaction of sex and hippocampal volume ratio did not predict cognitive performance across groups.

CONCLUSION

Our preliminary findings suggest that cognitively-unimpaired female carriers showed a verbal memory reserve, and as disease progresses, female carriers did not exhibit a cognitive susceptibility to AD-related neurodegeneration. Future studies with larger samples of autosomal dominant AD are warranted to further understand sex differences in AD-related clinical and pathological markers.

Validation of the Latin American Spanish version of the face-name associative memory exam in a Colombian Sample

OBJECTIVE

The Face-Name Associative Memory Exam (FNAME) has been used to detect subtle cognitive changes in clinically normal older adults at increased risk for Alzheimer's disease. FNAME assesses learning and delayed recall for face-name pairs. The aim of this study is to introduce a Latin American Spanish version of the FNAME (LAS-FNAME), examine its psychometric properties, and provide preliminary normative data in a sample of clinically normal, Spanish-speaking individuals from Antioquia, Colombia.

METHOD

59 clinically-normal individuals (71% females) were recruited by the Grupo de Neurociencias in Antioquia (Colombia). Age ranged from 27 to 82 years (M = 50.31, SD = 15.32) and years of education ranged from 2 to 17 years (M = 9.02, SD = 4.11). All participants completed the LAS-FNAME and a brief neuropsychological evaluation. We examined associations between age, education, and sex and performance on the LAS-FNAME. Internal consistency, convergent and discriminant validity were also assessed. Test-restest reliability was computed for a subset of participants (n = 32).

RESULTS

LAS-FNAME exhibited moderate convergent validity with other memory measures (Free and Cued Selective Reminding Scale, r _s=.465, p<.01; Wechsler Memory Scale III - Logical Memory Delayed Recall, r _s=.479, p<.01). The subscales of the LAS-FNAME exhibited adequate internal consistency (α=.825). Test-retest reliability analyses demonstrated consistency of scores over time. Normative data was stratified by age (<50, 50-65, >65) and low and high educational attainment (≤8 and >8 years of education, respectively).

CONCLUSIONS

The LAS-FNAME is a valid and reliable measure to assess memory in clinically normal, Spanish-speaking individuals from Colombia for clinical and research purposes.

Normative data stratified by age and education for a Spanish neuropsychological test battery: Results from the Colombian Alzheimer's prevention initiative registry

Neuropsychologists continue to face challenges when assessing Spanish-speaking individuals due to limited availability of normative data. We developed comprehensive normative data stratified by age and education for a Spanish neuropsychological test battery used by the Grupo de Neurociencias de Antioquia (Colombia) and the Colombian Alzheimer's Prevention Initiative Registry, which have followed large families at risk for autosomal-dominant Alzheimer's disease (ADAD) since the 1990s. Approximately 75% of these individuals are cognitively-unimpaired and are not genetically predisposed to develop ADAD. We conducted a retrospective study on neuropsychological evaluations from 2,673 cognitively unimpaired individuals (56% female), with ages ranging from 18 to 86 years and education from 1 to 25 years. Neuropsychological measures included the Consortium to Establish a Registry for Alzheimer's Disease-Colombia, and other multidomain Spanish tests. We examined associations between age, education, and sex with cognitive performance. Norms stratified by age and education are presented. Cognitive performance showed small associations with age and education and was unrelated to sex. We provided population-based norms for Spanish tests targeting multiple cognitive domains using a large Colombian sample. These normative data may be helpful for the neuropsychological characterization of Spanish speakers from Latin America in clinical and research settings.

Attention Measures of Accuracy, Variability, and Fatigue Detect Early Response to Donepezil in Alzheimer's Disease: A Randomized, Double-blind, Placebo-Controlled Pilot Trial

OBJECTIVE

Donepezil is widely used to treat Alzheimer's disease (AD), but detecting early response remains challenging for clinicians. Acetylcholine is known to directly modulate attention, particularly under high cognitive conditions, but no studies to date test whether measures of attention under high load can detect early effects of donepezil. We hypothesized that load-dependent attention tasks are sensitive to short-term treatment effects of donepezil, while global and other domain-specific cognitive measures are not.

METHOD

This longitudinal, randomized, double-blind, placebo-controlled pilot trial (ClinicalTrials.gov Identifier: NCT03073876) evaluated 23 participants newly diagnosed with AD initiating de novo donepezil treatment (5 mg). After baseline assessment, participants were randomized into Drug (n = 12) or Placebo (n = 11) groups, and retested after approximately 6 weeks. Cognitive assessment included: (a) attention tasks (Foreperiod Effect, Attentional Blink, and Covert Orienting tasks) measuring processing speed, top-down accuracy, orienting, intra-individual variability, and fatigue; (b) global measures (Alzheimer's Disease Assessment Scale-Cognitive Subscale, Mini-Mental Status Examination, Dementia Rating Scale); and (c) domain-specific measures (memory, language, visuospatial, and executive function).

RESULTS

The Drug but not the Placebo group showed benefits of treatment at high-load measures by preserving top-down accuracy, improving intra-individual variability, and averting fatigue. In contrast, other global or cognitive domain-specific measures could not detect treatment effects over the same treatment interval.

CONCLUSIONS

The pilot-study suggests that attention measures targeting accuracy, variability, and fatigue under high-load conditions could be sensitive to short-term cholinergic treatment. Given the central role of acetylcholine in attentional function, load-dependent attentional measures may be valuable cognitive markers of early treatment response.

Post-traumatic stress disorder dimensions and asthma morbidity in World Trade Center rescue and recovery workers

OBJECTIVE

Using data from a cohort of World Trade Center (WTC) rescue and recovery workers with asthma, we assessed whether meeting criteria for post-traumatic stress disorder (PTSD), sub-threshold PTSD, and for specific PTSD symptom dimensions are associated with increased asthma morbidity.

METHODS

Participants underwent a Structured Clinical Interview for Diagnostic and Statistical Manual to assess the presence of PTSD following DSM-IV criteria during in-person interviews between December 2013 and April 2015. We defined sub-threshold PTSD as meeting criteria for two of three symptom dimensions: re-experiencing, avoidance, or hyper-arousal. Asthma control, acute asthma-related healthcare utilization, and asthma-related quality of life data were collected using validated scales. Unadjusted and multiple regression analyses were performed to assess the relationship between sub-threshold PTSD and PTSD symptom domains with asthma morbidity measures.

RESULTS

Of the 181 WTC workers with asthma recruited into the study, 28% had PTSD and 25% had sub-threshold PTSD. Patients with PTSD showed worse asthma control, higher rates of inpatient healthcare utilization, and poorer asthma quality of life than those with sub-threshold or no PTSD. After adjusting for potential confounders, among patients not meeting the criteria for full PTSD, those presenting symptoms of re-experiencing exhibited poorer quality of life (p = 0.003). Avoidance was associated with increased acute healthcare use (p = 0.05). Sub-threshold PTSD was not associated with asthma morbidity (p > 0.05 for all comparisons).

CONCLUSIONS

There may be benefit in assessing asthma control in patients with sub-threshold PTSD symptoms as well as those with full PTSD to more effectively identify ongoing asthma symptoms and target management strategies.