The recency ratio as predictor of early MCI

ABSTRACTObjectives:Individuals with Alzheimer's disease (AD) present poor immediate primacy recall accompanied by intact or exaggerated recency, which then tends to decline after a delay. Bruno et al. (Journal of Clinical and Experimental Neuropsychology, Vol. 38, 2016, pp. 967-973) have shown that higher ratio scores between immediate and delayed recency (i.e. the recency ratio; Rr) are associated with cognitive decline in high-functioning older individuals. We tested whether Rr predicted conversion to early mild cognitive impairment (early MCI) from a cognitively healthy baseline.

DESIGN

Data were analyzed longitudinally with binomial regression. Baseline scores were used to predict conversion to early MCI after approximately nine years.

SETTING

Data were collected at the Wisconsin Registry of Alzheimer's Prevention, in Madison, Wisconsin.

PARTICIPANTS

For the study, 427 individuals were included in the analysis; all participants were 50 years of age or older and cognitively intact at baseline, and were native English speakers.

MEASUREMENTS

Memory data were collected using the Rey's Auditory Verbal Learning Test, and the early MCI diagnosis was obtained via consensus conference.

RESULTS

Our results showed that higher Rr scores are correlated with greater risk of later early MCI diagnosis, and this association is independent of total recall performance.

CONCLUSIONS

Rr is an emerging cognitive marker of cognitive decline.

Convergent Synthesis of the NS5B Inhibitor GSK8175 Enabled by Transition Metal Catalysis

A convergent eight-stage synthesis of the boron-containing NS5B inhibitor GSK8175 is described. The previous route involves 13 steps in a completely linear sequence, with an overall 10% yield. Key issues include a multiday S_NAr arylation of a secondary sulfonamide using HMPA as solvent, multiple functional group interconversions after all of the carbon atoms are installed (including a Sandmeyer halogenation), use of carcinogenic chloromethyl methyl ether to install a protecting group late in the synthesis, and an unreliable Pd-catalyzed Miyaura borylation as the penultimate step. We have devised an orthogonal approach using a Chan-Lam coupling between a halogenated aryl pinacol boronate ester and an aryl methanesulfonamide. This reaction is performed using a cationic Cu(I) precatalyst, which can be easily generated in situ using KPF₆ as a halide abstractor. High-throughput screening revealed a new Pd catalyst system to effect the penultimate borylation chemistry using simple monodentate phosphine ligands, with PCyPh₂ identified as optimal. Reaction progress analysis of this borylation indicated likely mass-transfer rate limitations under standard conditions using KOAc as the base. We have devised a K₂CO₃/pivalic acid system as an alternative, which dramatically outperforms the standard conditions. This new synthesis proceeds in eight stages with a 20% overall yield.

Differential 5-year brain atrophy rates in cognitively declining and stable APOE-ε4 elders

OBJECTIVE

The apolipoprotein E (APOE) ε4 allele is the most important genetic risk factor for late-onset Alzheimer's disease. Many ε4 carriers, however, never develop Alzheimer's disease. The purpose of this study is to characterize the variability in phenotypic expression of the ε4 allele, as measured by the longitudinal trajectory of cognitive test scores and MRI brain volumes, in cognitively intact elders.

METHOD

Healthy older adults, ages 65-85, participated in a 5-year longitudinal study that included structural MRI and cognitive testing administered at baseline and at 1.5 and 5 years postenrollment. Participants included 22 ε4 noncarriers, 15 ε4 carriers who experienced a decline in cognition over the 5-year interval, and 11 ε4 carriers who remained cognitively stable.

RESULTS

No baseline cognitive or volumetric group differences were observed. Compared to noncarriers, declining ε4 carriers had significantly greater rates of atrophy in left (p = .001, Cohen's d = .691) and right (p = .003, d = .622) cortical gray matter, left (p = .003, d = .625) and right (p = .020, d = .492) hippocampi, and greater expansion of the right inferior lateral ventricle (p < .001, d = .751) over 5 years.

CONCLUSIONS

This study illustrates the variability in phenotypic expression of the ε4 allele related to neurodegeneration. Specifically, only those individuals who exhibited longitudinal declines in cognitive function experienced concomitant changes in brain volume. Future research is needed to better understand the biological and lifestyle factors that may influence the expression of the ε4 allele. (PsycINFO Database Record

Synthesis and antiproliferative activity of derivatives of the phyllanthusmin class of arylnaphthalene lignan lactones

A series of arylnaphthalene lignan lactones based on the structure of the phyllanthusmins, a class of potent natural products possessing diphyllin as the aglycone, has been synthesized and screened for activity against multiple cancer cell lines. SAR exploration was performed on both the carbohydrate and lactone moieties of this structural class. These studies have revealed the importance of functionalization of the carbohydrate hydroxy groups with both acetylated and methylated analogues showing increased potency relative to those with unsubstituted sugar moieties. In addition, the requirement for the presence and position of the C-ring lactone has been demonstrated through reduction and selective re-oxidation of the lactone ring. The most potent compound in this study displayed an IC₅₀ value of 18 nM in an HT-29 assay with several others ranging from 50 to 200 nM. In an effort to elucidate their potential mechanism(s) of action, the DNA topoisomerase IIa inhibitory activity of the most potent compounds was examined based on previous reports of structurally similar compounds, but does not appear to contribute significantly to their antiproliferative effects.

Guillain-BarrÉ syndrome subtype diagnosis: A prospective multicentric European study

INTRODUCTION

There is uncertainty as to whether the Guillain-Barré syndrome (GBS) subtypes, acute inflammatory demyelinating polyradiculoneuropathy (AIDP) and acute motor axonal neuropathy (AMAN), can be diagnosed electrophysiologically.

METHODS

We prospectively included 58 GBS patients. Electrodiagnostic testing (EDX) was performed at means of 5 and 33 days after disease onset. Two traditional and one recent criteria sets were used to classify studies as demyelinating or axonal. Results were correlated with anti-ganglioside antibodies and reversible conduction failure (RCF).

RESULTS

No classification shifts were observed, but more patients were classified as axonal with recent criteria. RCF and anti-ganglioside antibodies were present in both subtypes, more frequently in the axonal subtype.

DISCUSSION

Serial EDX has no effect on GBS subtype proportions. The absence of exclusive correlation with RCF and anti-ganglioside antibodies may challenge the concept of demyelinating and axonal GBS subtypes based upon electrophysiological criteria. Frequent RCF indicates that nodal/paranodal alterations may represent the main pathophysiology. Muscle Nerve, 2018.

Motor timing intraindividual variability in amnestic mild cognitive impairment and cognitively intact elders at genetic risk for Alzheimer's disease

INTRODUCTION

Intraindividual variability (IIV) in motor performance has been shown to predict future cognitive decline. The apolipoprotein E-epsilon 4 (APOE-ε4) allele is also a well-established risk factor for memory decline. Here, we present novel findings examining the influence of the APOE-ε4 allele on the performance of asymptomatic healthy elders in comparison to individuals with amnestic MCI (aMCI) on a fine motor synchronization, paced finger-tapping task (PFTT).

METHOD

Two Alzheimer's disease (AD) risk groups, individuals with aMCI (n = 24) and cognitively intact APOE-ε4 carriers (n = 41), and a control group consisting of cognitively intact APOE-ε4 noncarriers (n = 65) completed the Rey Auditory Verbal Learning Test and the PFTT, which requires index finger tapping in synchrony with a visual stimulus (interstimulus interval = 333 ms).

RESULTS

Motor timing IIV, as reflected by the standard deviation of the intertap interval (ITI), was greater in the aMCI group than in the two groups of cognitively intact elders; in contrast, all three groups had statistically equivalent mean ITI. No significant IIV differences were observed between the asymptomatic APOE-ε4 carriers and noncarriers. Poorer episodic memory performance was associated with greater IIV, particularly in the aMCI group.

CONCLUSIONS

Results suggest that increased IIV on a fine motor synchronization task is apparent in aMCI. This IIV measure was not sensitive in discriminating older asymptomatic individuals at genetic risk for AD from those without such a genetic risk. In contrast, episodic memory performance, a well-established predictor of cognitive decline in preclinical AD, was able to distinguish between the two cognitively intact groups based on genetic risk.

A quarter century of advances in the statistical analysis of longitudinal neuropsychological data

OBJECTIVE

Over the last 25 years, there has been an unprecedented increase in federal funding for large-scale longitudinal studies, many of which collect neuropsychological or neuroimaging outcome measures. These studies have collected data from thousands of study participants across multiple waves of data collection over many years. With the increased availability of longitudinal data, data sharing policies have become more liberal, thereby offering significant opportunities for interested researchers to carry out their own longitudinal research with these data. At the same time, these opportunities have stimulated new conceptualizations of longitudinal change and have led to the development of novel approaches toward analysis of longitudinal data. My aim is to review these new conceptualizations and novel data analytic approaches.

METHOD

In this article, I describe the state of the field a quarter century ago with respect to available longitudinal studies, and I trace the growth of federally funded longitudinal studies over the last 25 years by describing 18 of these projects, many of which are still collecting data. In the second part of this article, I describe changes in the methods used to analyze longitudinal data, transitioning from the paired t test and repeated measures ANOVA to latent change scores, linear mixed effects modeling, and latent growth curve models. Changes in the approach to management of missing data are also discussed.

CONCLUSIONS

Future studies should abandon traditional longitudinal analytic methods in favor of contemporary approaches given their increased power, greater accuracy, and widespread availability. (PsycINFO Database Record

Five-Year Longitudinal Brain Volume Change in Healthy Elders at Genetic Risk for Alzheimer's Disease

Neuropathological changes associated with Alzheimer's disease (AD) precede symptom onset by more than a decade. Possession of an apolipoprotein E (APOE) ɛ4 allele is the strongest genetic risk factor for late onset AD. Cross-sectional studies of cognitively intact elders have noted smaller hippocampal/medial temporal volumes in ɛ4 carriers (ɛ4+) compared to ɛ4 non-carriers (ɛ4-). Few studies, however, have examined long-term, longitudinal, anatomical brain changes comparing healthy ɛ4+ and ɛ4- individuals. The current five-year study examined global and regional volumes of cortical and subcortical grey and white matter and ventricular size in 42 ɛ4+ and 30 ɛ4- individuals. Cognitively intact participants, ages 65-85 at study entry, underwent repeat anatomical MRI scans on three occasions: baseline, 1.5, and 4.75 years. Results indicated no between-group volumetric differences at baseline. Over the follow-up interval, the ɛ4+ group experienced a greater rate of volume loss in total grey matter, bilateral hippocampi, right hippocampal subfields, bilateral lingual gyri, bilateral parahippocampal gyri, and right lateral orbitofrontal cortex compared to the ɛ4- group. Greater loss in grey matter volumes in ɛ4+ participants were accompanied by greater increases in lateral, third, and fourth ventricular volumes. Rate of change in white matter volumes did not differentiate the groups. The current results indicate that longitudinal measurements of brain atrophy can serve as a sensitive biomarker for identifying neuropathological changes in persons at genetic risk for AD and potentially, for assessing the efficacy of treatments designed to slow or prevent disease progression during the preclinical stage of AD.

Diffusion Tensor Imaging Predictors of Episodic Memory Decline in Healthy Elders at Genetic Risk for Alzheimer's Disease

OBJECTIVES

White matter (WM) integrity within the mesial temporal lobe (MTL) is important for episodic memory (EM) functioning. The current study investigated the ability of diffusion tensor imaging (DTI) in MTL WM tracts to predict 3-year changes in EM performance in healthy elders at disproportionately higher genetic risk for Alzheimer's disease (AD).

METHODS

Fifty-one cognitively intact elders (52% with family history (FH) of dementia and 33% possessing an Apolipoprotein E ε4 allelle) were administered the Rey Auditory Verbal Learning Test (RAVLT) at study entry and at 3-year follow-up. DTI scanning, conducted at study entry, examined fractional anisotropy and mean, radial and axial diffusion within three MTL WM tracts: uncinate fasciculus (UNC), cingulate-hippocampal (CHG), and fornix-stria terminalis (FxS). Correlations were performed between residualized change scores computed from RAVLT trials 1-5, immediate recall, and delayed recall scores and baseline DTI measures; MTL gray matter (GM) and WM volumes; demographics; and AD genetic and metabolic risk factors.

RESULTS

Higher MTL mean and axial diffusivity at baseline significantly predicted 3-year changes in EM, whereas baseline MTL GM and WM volumes, FH, and metabolic risk factors did not. Both ε4 status and DTI correlated with change in immediate recall.

CONCLUSIONS

Longitudinal EM changes in cognitively intact, healthy elders can be predicted by disruption of the MTL WM microstructure. These results are derived from a sample with a disproportionately higher genetic risk for AD, suggesting that the observed WM disruption in MTL pathways may be related to early neuropathological changes associated with the preclinical stage of AD. (JINS, 2016, 22, 1005-1015).

Does cognitive self-consciousness link older adults' cognitive functioning to obsessive-compulsive symptoms?

To elucidate how obsessional symptoms might develop or intensify in late-life, we tested a risk model. We posited that cognitive self-consciousness (CSC), a tendency to be aware of and monitor thinking, would increase reactivity to aging-related cognitive changes and mediate the relationship between cognitive functioning and obsessive-compulsive disorder (OCD) symptoms. Older adults (Mage = 76.7 years) completed the Dementia Rating Scale-2 (DRS-2), a CSC measure, and an OCD symptom measure up to four times over 18 months. A model that included DRS-2 age and education adjusted total score as the indicator of cognitive functioning fit the data well, and CSC score change mediated the relationship between initial cognitive functioning and changes in OCD symptoms. In tests of a model that included DRS-2 Initiation/Perseveration (I/P) and Conceptualization subscale scores, the model again fit the data well. Conceptualization scores, but not I/P scores, were related to later OCD symptoms, and change in CSC scores again mediated the relationship. Lower scores on initial cognitive functioning measures predicted increases in CSC scores over time, which in turn predicted increases in OCD symptoms over the 18 months of the study. Implications for understanding late-life obsessional problems are discussed.

Brain pathologies in extreme old age

With an emphasis on evolving concepts in the field, we evaluated neuropathologic data from very old research volunteers whose brain autopsies were performed at the University of Kentucky Alzheimer's Disease Center, incorporating data from the Georgia Centenarian Study (n = 49 cases included), Nun Study (n = 17), and University of Kentucky Alzheimer's Disease Center (n = 11) cohorts. Average age of death was 102.0 (range: 98-107) years overall. Alzheimer's disease pathology was not universal (62% with "moderate" or "frequent" neuritic amyloid plaque densities), whereas frontotemporal lobar degeneration was absent. By contrast, some hippocampal neurofibrillary tangles (including primary age-related tauopathy) were observed in every case. Lewy body pathology was seen in 16.9% of subjects and hippocampal sclerosis of aging in 20.8%. We describe anatomic distributions of pigment-laden macrophages, expanded Virchow-Robin spaces, and arteriolosclerosis among Georgia Centenarians. Moderate or severe arteriolosclerosis pathology, throughout the brain, was associated with both hippocampal sclerosis of aging pathology and an ABCC9 gene variant. These results provide fresh insights into the complex cerebral multimorbidity, and a novel genetic risk factor, at the far end of the human aging spectrum.

Trichormamides C and D, antiproliferative cyclic lipopeptides from the cultured freshwater cyanobacterium cf. Oscillatoria sp. UIC 10045

Extract from the cultured freshwater cf. Oscillatoria sp. UIC 10045 showed antiproliferative activity against HT-29 cell line. Bioassay-guided fractionation led to the isolation of two new cyclic lipopeptides, named trichormamides C (1) and D (2). The planar structures were determined by combined analyses of HRESIMS, Q-TOF ESIMS/MS, and 1D and 2D NMR spectra. The absolute configurations of the amino acid residues were assigned by advanced Marfey's analysis after partial and complete acid hydrolysis. Trichormamides C (1) is a cyclic undecapeptide and D (2) is a cyclic dodecapeptide, both containing a lipophilic β-aminodecanoic acid residue. Trichormamide C (1) displayed antiproliferative activities against HT-29 and MDA-MB-435 cancer cell lines with IC50 values of 1.7 and 1.0μM, respectively, as well as anti-Mycobacterium tuberculosis activity with MIC value of 23.8μg/mL (17.3μM). Trichormamide D (2) was found to be less potent against both HT-29 and MDA-MB-435 cancer cell lines with IC50 values of 11.5 and 11.7μM, respectively.

Resting State Functional Connectivity in Mild Traumatic Brain Injury at the Acute Stage: Independent Component and Seed-Based Analyses

Mild traumatic brain injury (mTBI) accounts for more than 1 million emergency visits each year. Most of the injured stay in the emergency department for a few hours and are discharged home without a specific follow-up plan because of their negative clinical structural imaging. Advanced magnetic resonance imaging (MRI), particularly functional MRI (fMRI), has been reported as being sensitive to functional disturbances after brain injury. In this study, a cohort of 12 patients with mTBI were prospectively recruited from the emergency department of our local Level-1 trauma center for an advanced MRI scan at the acute stage. Sixteen age- and sex-matched controls were also recruited for comparison. Both group-based and individual-based independent component analysis of resting-state fMRI (rsfMRI) demonstrated reduced functional connectivity in both posterior cingulate cortex (PCC) and precuneus regions in comparison with controls, which is part of the default mode network (DMN). Further seed-based analysis confirmed reduced functional connectivity in these two regions and also demonstrated increased connectivity between these regions and other regions of the brain in mTBI. Seed-based analysis using the thalamus, hippocampus, and amygdala regions further demonstrated increased functional connectivity between these regions and other regions of the brain, particularly in the frontal lobe, in mTBI. Our data demonstrate alterations of multiple brain networks at the resting state, particularly increased functional connectivity in the frontal lobe, in response to brain concussion at the acute stage. Resting-state functional connectivity of the DMN could serve as a potential biomarker for improved detection of mTBI in the acute setting.

Genetic risk for Alzheimer's disease alters the five-year trajectory of semantic memory activation in cognitively intact elders

Healthy aging is associated with cognitive declines typically accompanied by increased task-related brain activity in comparison to younger counterparts. The Scaffolding Theory of Aging and Cognition (STAC) (Park and Reuter-Lorenz, 2009; Reuter-Lorenz and Park, 2014) posits that compensatory brain processes are responsible for maintaining normal cognitive performance in older adults, despite accumulation of aging-related neural damage. Cross-sectional studies indicate that cognitively intact elders at genetic risk for Alzheimer's disease (AD) demonstrate patterns of increased brain activity compared to low risk elders, suggesting that compensation represents an early response to AD-associated pathology. Whether this compensatory response persists or declines with the onset of cognitive impairment can only be addressed using a longitudinal design. The current prospective, 5-year longitudinal study examined brain activation in APOE ε4 carriers (N=24) and non-carriers (N=21). All participants, ages 65-85 and cognitively intact at study entry, underwent task-activated fMRI, structural MRI, and neuropsychological assessments at baseline, 18, and 57 months. fMRI activation was measured in response to a semantic memory task requiring participants to discriminate famous from non-famous names. Results indicated that the trajectory of change in brain activation while performing this semantic memory task differed between APOE ε4 carriers and non-carriers. The APOE ε4 group exhibited greater activation than the Low Risk group at baseline, but they subsequently showed a progressive decline in activation during the follow-up periods with corresponding emergence of episodic memory loss and hippocampal atrophy. In contrast, the non-carriers demonstrated a gradual increase in activation over the 5-year period. Our results are consistent with the STAC model by demonstrating that compensation varies with the severity of underlying neural damage and can be exhausted with the onset of cognitive symptoms and increased structural brain pathology. Our fMRI results could not be attributed to changes in task performance, group differences in cerebral perfusion, or regional cortical atrophy.

Octogenarian and centenarian performance on the Fuld Object Memory Evaluation

The Fuld Object Memory Evaluation (FOME) has considerable utility for cognitive assessment in older adults, but there are few normative data, particularly for the oldest old. In this study, 80 octogenarians and 244 centenarians from the Georgia Centenarian Study completed the FOME. Total and trial-to-trial performance on the storage, retrieval, repeated retrieval, and ineffective reminder indices were assessed. Additional data stratified by age group, education, and cognitive impairment are provided in the Supplemental data. Octogenarians performed significantly better than centenarians on all FOME measures. Neither age group benefitted from additional learning trials beyond Trial 3 for storage and Trial 2 for retention and retrieval. Ineffective reminders showed no change across learning trials for octogenarians, while centenarians improved only between Trials 1 and 2. This minimal improvement past Trial 2 indicates that older adults might benefit from a truncated version of the test that does not include trials three through five, with the added benefit of reducing testing burden in this population.

Trichormamides A and B with Antiproliferative Activity from the Cultured Freshwater Cyanobacterium Trichormus sp. UIC 10339

Two new cyclic lipopeptides, trichormamides A (1) and B (2), were isolated from the cultured freshwater cyanobacterium Trichormus sp. UIC 10339. The strain was obtained from a sample collected in Raven Lake in Northern Wisconsin. The planar structures of trichormamides A (1) and B (2) were determined using a combination of spectroscopic analyses including HRESIMS and 1D and 2D NMR experiments. The absolute configurations of the amino acid residues were assigned by the advanced Marfey's method after acid hydrolysis. Trichormamide A (1) is a cyclic undecapeptide containing two D-amino acid residues (D-Tyr and D-Leu) and one β-amino acid residue (β-aminodecanoic acid). Trichormamide B (2) is a cyclic dodecapeptide characterized by the presence of four nonstandard α-amino acid residues (homoserine, N-methylisoleucine, and two 3-hydroxyleucines) and one β-amino acid residue (β-aminodecanoic acid). Trichormamide B (2) was cytotoxic against MDA-MB-435 and HT-29 cancer cell lines with IC50 values of 0.8 and 1.5 μM, respectively.

Rocaglamide, silvestrol and structurally related bioactive compounds from Aglaia species

Covering: 2006 to 2013. Investigations on the chemistry and biology of rocaglamide, silvestrol and structurally related bioactive compounds from Aglaia species during the period 2006-2013 are reviewed. Included are new phytochemical studies of naturally occurring rocaglamide derivatives, an update on synthetic methods for cyclopenta[b]benzofurans, and a description of the recent biological evaluation and mechanism-of-action studies on compounds of this type.

Physical activity reduces hippocampal atrophy in elders at genetic risk for Alzheimer's disease

We examined the impact of physical activity (PA) on longitudinal change in hippocampal volume in cognitively intact older adults at varying genetic risk for the sporadic form of Alzheimer's disease (AD). Hippocampal volume was measured from structural magnetic resonance imaging (MRI) scans administered at baseline and at an 18-month follow-up in 97 healthy, cognitively intact older adults. Participants were classified as High or Low PA based on a self-report questionnaire of frequency and intensity of exercise. Risk status was defined by the presence or absence of the apolipoprotein E-epsilon 4 (APOE-ε4) allele. Four subgroups were studied: Low Risk/High PA (n = 24), Low Risk/Low PA (n = 34), High Risk/High PA (n = 22), and High Risk/Low PA (n = 17). Over the 18 month follow-up interval, hippocampal volume decreased by 3% in the High Risk/Low PA group, but remained stable in the three remaining groups. No main effects or interactions between genetic risk and PA were observed in control brain regions, including the caudate, amygdala, thalamus, pre-central gyrus, caudal middle frontal gyrus, cortical white matter (WM), and total gray matter (GM). These findings suggest that PA may help to preserve hippocampal volume in individuals at increased genetic risk for AD. The protective effects of PA on hippocampal atrophy were not observed in individuals at low risk for AD. These data suggest that individuals at genetic risk for AD should be targeted for increased levels of PA as a means of reducing atrophy in a brain region critical for the formation of episodic memories.

Assessing Older Adults' Obsessive-Compulsive Disorder Symptoms: Psychometric Characteristics of the Obsessive Compulsive Inventory-Revised

The lack of Obsessive-Compulsive disorder (OCD) symptom measures validated for use with older adults has hindered research and treatment development for the age group. We evaluated the Obsessive-Compulsive Inventory-Revised (OCI-R; Foa et al., 2002) with participants aged 65 and older (N = 180) to determine if the measure was an effective tool for evaluating obsessional symptoms. Participants completed the OCI-R and a comprehensive assessment battery up to four times over approximately 18 months. Results supported the well-replicated latent structure of the OCI-R (i.e., Washing, Checking, Ordering, Obsessing, Hoarding, and Neutralizing.). OCI-R total score was robustly associated with OCD symptoms assessed 18 months later by clinical interview, while scores on self-report measures of worry, general anxiety, and depression were not. Results indicate the OCI-R is an effective OCD symptom measure for older adults, although replication with additional older adult samples is needed.

Performance variability during a multitrial list-learning task as a predictor of future cognitive decline in healthy elders

INTRODUCTION

In clinical settings, neuropsychological test performance is traditionally evaluated with total summary scores (TSS). However, recent studies demonstrated that indices of intraindividual variability (IIV) yielded unique information complementing TSS. This 18-month longitudinal study sought to determine whether IIV indices derived from a multitrial list-learning test (the Rey Auditory Verbal Learning Test) provided incremental utility in predicting cognitive decline in older adults compared to TSS.

METHOD

Ninety-nine cognitively intact older adults (aged 65 to 89 years) underwent neuropsychological testing (including the Rey Auditory Verbal Learning Test) at baseline and 18-month follow-up. Participants were classified as cognitively stable (n = 65) or declining (n = 34) based on changes in their neuropsychological test performance. Logistic regression modeling tested the ability of baseline TSS indices (sum of Trials 1-5, immediate recall, and delayed recall) and IIV indices (lost access and gained access) to discriminate between stable and declining individuals.

RESULTS

Higher values of both lost access and gained access at baseline were associated with an increased risk for decline at 18-month follow-up. Further, the IIV indices provided predictive utility above and beyond the TSS indices.

CONCLUSION

These results highlight the value of analyzing IIV in addition to TSS during neuropsychological evaluation in older adults. High levels of IIV may reflect impairment in anterograde memory systems and/or executive dysfunction that may serve as a prognostic indicator of cognitive decline.

Recognition of famous names predicts cognitive decline in healthy elders

OBJECTIVE

The ability to recognize familiar people is impaired in both Mild Cognitive Impairment (MCI) and Alzheimer's Dementia (AD). In addition, both groups often demonstrate a time-limited temporal gradient (TG) in which well known people from decades earlier are better recalled than those learned recently. In this study, we examined the TG in cognitively intact elders for remote famous names (1950-1965) compared to more recent famous names (1995-2005). We hypothesized that the TG pattern on a famous name recognition task (FNRT) would predict future cognitive decline, and also show a significant correlation with hippocampal volume.

METHOD

Seventy-eight healthy elders (ages 65-90) with age-appropriate cognitive functioning at baseline were administered a FNRT. Follow-up testing 18 months later produced two groups: Declining (≥ 1 SD reduction on at least one of three measures) and Stable (< 1 SD).

RESULTS

The Declining group (N = 27) recognized fewer recent famous names than the Stable group (N = 51), although recognition for remote names was comparable. Baseline MRI volumes for both the left and right hippocampi were significantly smaller in the Declining group than the Stable group. Smaller baseline hippocampal volume was also significantly correlated with poorer performance for recent, but not remote famous names. Logistic regression analyses indicated that baseline TG performance was a significant predictor of group status (Declining vs. Stable) independent of chronological age and APOE ε4 inheritance.

CONCLUSIONS

The TG for famous name recognition may serve as an early preclinical cognitive marker of cognitive decline in healthy older individuals.