Socioemotional Dysfunction From Temporal Lobe Involvement in Frontotemporal Dementia: A Preliminary Report.

OBJECTIVE: Socioemotional changes, rather than cognitive impairments, are the feature that defines behavioral variant frontotemporal dementia (bvFTD). Investigators have attributed the socioemotional changes in bvFTD and other dementias to frontal lobe dysfunction; however, recent work implies a further contribution from right anterior temporal disease. The authors evaluated relationships between regional brain atrophy and socioemotional changes in both bvFTD and early-onset Alzheimer's disease (EOAD). METHODS: This study explored the neuroanatomical correlations of performance on the Socioemotional Dysfunction Scale (SDS), an instrument previously shown to document socioemotional changes in bvFTD, among 13 patients with bvFTD not preselected for anterior temporal involvement and 16 age-matched patients with early-onset Alzheimer's disease (EOAD). SDS scores were correlated with volumes of regions of interest assessed with tensor-based morphometric analysis of MRI images. RESULTS: As expected, the bvFTD group had significantly higher SDS scores overall and smaller frontal regions compared with the EOAD group, which in turn had smaller volumes in temporoparietal regions. SDS scores significantly correlated with lateral anterior temporal lobe (ATL) atrophy, and a regression analysis that controlled for diagnosis indicated that SDS scores predicted lateral ATL volume. Within the bvFTD group, higher SDS scores were associated with smaller lateral and right ATL regions, as well as a smaller orbitofrontal cortex. Within the EOAD group, higher SDS scores were associated with a smaller right parietal cortex. CONCLUSIONS: This study confirms that, in addition to orbitofrontal disease, there is a prominent right and lateral ATL origin of socioemotional changes in bvFTD and further suggests that right parietal involvement contributes to socioemotional changes in EOAD.

Emotional Awareness and Expression Therapy vs Cognitive Behavioral Therapy for Chronic Pain in Older Veterans: A Randomized Clinical Trial.

Importance: Chronic pain is common and disabling in older adults, and psychological interventions are indicated. However, the gold standard approach, cognitive-behavioral therapy (CBT), produces only modest benefits, and more powerful options are needed. Objectives: To evaluate whether emotional awareness and expression therapy (EAET) is superior to CBT for treatment of chronic pain among predominantly male older veterans and whether higher baseline depression, anxiety, or posttraumatic stress disorder (PTSD) symptoms-key targets of EAET-moderate treatment response. Design, Setting, and Participants: This 2-arm randomized clinical trial was conducted from May 16, 2019, to September 14, 2023, in the US Department of Veterans Affairs Greater Los Angeles Healthcare System. The trial included a racially and ethnically diverse group of veterans aged 60 to 95 years with at least 3 months of musculoskeletal pain. Interventions: Emotional awareness and expression therapy or CBT, conducted concurrently, each presented as one 90-minute individual session followed by eight 90-minute group sessions. Main Outcomes and Measures: The primary outcome was Brief Pain Inventory pain severity (range, 0 to 10) from baseline to posttreatment (week 10, primary end point) and 6-month follow-up. Secondary outcomes included Patient Reported Outcomes Institute Measurement System Anxiety, Depression, Fatigue, General Life Satisfaction (NIH Toolbox), Pain Interference, and Sleep Disturbance Short Forms, Patient Global Impression of Change (PGIC), and Satisfaction with Therapy and Therapist Scale-Revised. A subset of participants completed the PTSD Checklist for Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition). All analyses were for the intention-to-treat population and included all randomized participants. Results: Among 126 randomized participants (66 in the EAET group and 60 in the CBT group; mean [SD] age, 71.9 [5.9] years; 116 [92%] male), 111 (88%) completed posttreatment, and 104 (82%) completed the 6-month follow-up. The EAET was superior to CBT for the primary outcome of reduction in pain severity at posttreatment (estimate, -1.59 [95% CI, -2.35 to -0.83]; P < .001) and follow-up (estimate, -1.01 [95% CI, -1.78 to -0.24]; P = .01). A greater percentage of participants in EAET vs CBT had clinically significant (at least 30%) pain reduction (63% vs 17%; odds ratio, 21.54 [95% CI, 4.66-99.56]; P < .001) at posttreatment. In addition, EAET was superior to CBT on 50% pain reduction (35% vs 7%; odds ratio, 11.77 [95% CI, 2.38-58.25]; P = .002), anxiety (estimate, -2.49 [95% CI, -4.30 to -0.68]; P = .006), depression (estimate, -3.06 [95% CI, -5.88 to -0.25]; P = .03), general life satisfaction (estimate, 1.23 [95% CI, 0.36-2.10]; P = .005), PTSD symptoms (estimate, -4.39 [95% CI, -8.44 to -0.34]; P = .03), PGIC score (estimate, 1.46 [95% CI, 0.77-2.15]; P < .001), and global treatment satisfaction (estimate, 0.28 [95% CI, 0.12-0.45]; P < .001) at posttreatment. Higher baseline depression (estimate, -1.55 [95% CI, -0.37 to 2.73]; P < .001), anxiety (estimate, -1.53 [95% CI, -2.19 to -0.88]; P < .001), and PTSD symptoms (estimate, -1.69 [95% CI, -2.96 to -0.42]; P = .009) moderated greater reduction in pain severity after EAET but not CBT. Conclusions and Relevance: The results of this randomized clinical trial suggest that EAET may be a preferred intervention for medically and psychiatrically complex patients with pain. The societal burden of chronic pain could be improved by further incorporating the principles of EAET into mainstream clinical pain medicine. Trial Registration: ClinicalTrials.gov Identifier: NCT03918642.

Video telehealth emotional awareness and expression therapy for older U.S. military veterans with chronic pain: A pilot study.

OBJECTIVES: Emotional Awareness and Expression Therapy (EAET) targets trauma and emotional conflict to reduce or eliminate chronic pain, but video telehealth administration is untested. This uncontrolled pilot assessed acceptability, feasibility, and preliminary efficacy of group-based video telehealth EAET (vEAET) for older veterans with chronic musculoskeletal pain. METHODS: Twenty veterans were screened, and 16 initiated vEAET, delivered as one 60-minute individual session and eight 90-minute group sessions. Veterans completed posttreatment satisfaction ratings and pain severity (primary outcome), pain interference, anxiety, depression, functioning, social connectedness, shame, and anger questionnaires at baseline, posttreatment, and 2-month follow-up. RESULTS: Satisfaction was high, and veterans attended 7.4 (SD = 0.6) of 8 group sessions; none discontinued treatment. Veterans attained significant, large reductions in pain severity from baseline to posttreatment (p < .001, Hedges' g = -1.54) and follow-up (p < .001, g = -1.20); 14 of 16 achieved clinically significant (≥ 30%) pain reduction, and 3 achieved 90-100% pain reduction. Secondary outcomes demonstrated significant, medium-to-large improvements. CONCLUSIONS: In this small sample, vEAET produced better attendance, similar benefits, and fewer dropouts than in-person EAET in prior studies. Larger, controlled trials are needed. CLINICAL IMPLICATIONS: Group vEAET appears feasible and highly effective for older veterans with chronic pain.

A Transdisciplinary Program for Care of Veterans With Neurocognitive Disorders.

Background: Veterans face specific risk factors for neurocognitive disorders. Providing them with comprehensive care for dementia and related neurocognitive disorders is a challenge as the population ages. There is a need for family-centered interventions, specialized expertise, and collaboration among clinicians and caregivers. The literature suggests that application of a transdisciplinary care model can address these needs and provide effective dementia care. Observations: The Veterans Affairs Greater Los Angeles Healthcare System has employed existing expertise to create a conference-centered transdisciplinary model that responds to the US Department of Veterans Affairs directive for a dementia system of care. This model involves direct participation of behavioral neurology, geriatric psychiatry, geriatrics, neuropsychology, nursing, and social work. In this model, the social worker serves as a dementia care manager and, along with the nurse specialist, assures long-term management through follow-up and monitoring. Transdisciplinary interactions occur in a clinical case conference where each discipline contributes to the veteran's care. The team generates a final report on treating these veterans, the caregiver's needs, referral for psychosocial services, and plans for monitoring and follow-up. Conclusions: This model could be a template of a program for implementing the Dementia System of Care across Veteran Affairs medical centers.

Physical Function Effects of Live Video Group Exercise Interventions for Older Adults: A Systematic Review and Veteran's Gerofit Group Case Study.

Background: Literature on telehealth interventions for older adults has been primarily on asynchronous interventions. During the COVID-19 pandemic, older adult exercise programs transitioned to an online format. This systematic review and case study examines the effectiveness of older adult live video exercise group interventions on physical health with insights from a Los Angeles VA program, Gerofit. Methods: PubMed was searched for live video older adult exercise groups from database inception to November 2021. All eligible studies included assessments of physical health and were limited to participants with an average age of 65 years or greater. Ten Veterans, who had participated in both in-person and virtual Gerofit sessions, were surveyed in the case study. Results: Nine studies met the inclusion criteria. Four studies included an equivalent in-person group as a comparator to the live video group and reported no significant between-group differences in outcomes, including energy expenditure and 6-minute walking distance test (6MWD). The other five studies reported statistically significant in-group improvement in outcomes including isokinetic knee strength. Case study participants reported similar attendance rates and perceived benefits, such as improved balance, when comparing virtual and in-person sessions. Discussion: Live video exercise groups in older adults demonstrated an improvement in physical function that was not statistically different from the comparison in-person sessions with the added benefit of averaging a higher attendance rate, providing initial support for the use of live video in older adult exercise programs. Insights from the case study supplement this by demonstrating older adults' positive attitude on these groups.

Pathophysiology of Alzheimer's Disease.

Alzheimer's disease (AD) is the most common neurodegenerative disease leading to dementia worldwide. While neuritic plaques consisting of aggregated amyloid-beta proteins and neurofibrillary tangles of accumulated tau proteins represent the pathophysiologic hallmarks of AD, numerous processes likely interact with risk and protective factors and one's culture to produce the cognitive loss, neuropsychiatric symptoms, and functional impairments that characterize AD dementia. Recent biomarker and neuroimaging research has revealed how the pathophysiology of AD may lead to symptoms, and as the pathophysiology of AD gains clarity, more potential treatments are emerging that aim to modify the disease and relieve its burden.

Cholinergic receptor binding in unimpaired older adults, mild cognitive impairment, and Alzheimer's disease dementia.

BACKGROUND: Cholinergic neurotransmitter system dysfunction contributes to cognitive impairment in Alzheimer's disease and other syndromes. However, the specific cholinergic mechanisms and brain structures involved, time course of alterations, and relationships with specific cognitive deficits are not well understood. METHODS: This study included 102 older adults: 42 cognitively unimpaired (CU), 28 with mild cognitive impairment (MCI), and 32 with Alzheimer's disease (AD) dementia. Each participant underwent a neuropsychological assessment. Regional brain α4ß2 nicotinic cholinergic receptor binding (VT/fp) was measured using 2-[18F]fluoro-3-(2(S)azetidinylmethoxy)pyridine (2FA) and PET imaging. Voxel-wise analyses of group differences were performed. Relationships between receptor binding and cognition, age, and cholinesterase inhibitor medication use were assessed using binding values in six prespecified regions of interest. RESULTS: SPM analysis showed the group VT/fp binding differences in the bilateral entorhinal cortex, hippocampus, insula, anterior cingulate, thalamus, and basal ganglia (p < .05, FWE-corrected). Pairwise comparisons revealed lower binding in the AD group compared to the CU group in similar regions. Binding in the entorhinal cortex was lower in the MCI group than in the CU group; binding in the hippocampus was lower in the AD group than in the MCI group. AD participants taking cholinesterase inhibitor medication had lower 2FA binding in the bilateral hippocampus and thalamus compared to those not taking medication. In the CU group, age was negatively associated with 2FA binding in each region of interest (rs = - .33 to - .59, p < .05 for each, uncorrected). Attention, immediate recall, and delayed recall scores were inversely associated with 2FA binding in most regions across the full sample. In the combined group of CU and MCI participants, attention was inversely associated with 2FA binding in most regions, beyond the effect of hippocampal volume. CONCLUSIONS: Nicotinic cholinergic receptor binding in specific limbic and subcortical regions is lower in MCI and further reduced in AD dementia, compared to CU older adults, and is related to cognitive deficits. Cognitive decline with age may be a consequence of reduced cholinergic receptor density or binding affinity that may also promote vulnerability to other Alzheimer's processes. Contemporary modification of the "cholinergic deficit" of aging and AD may reveal opportunities to prevent or improve clinical symptoms.

PTSD Improvement Associated with Social Connectedness in Gerofit Veterans Exercise Program.

OBJECTIVE: Post-traumatic stress disorder (PTSD) is common in Veterans. Symptoms can perpetuate into late life, negatively impacting physical and mental health. Exercise and social support are beneficial in treating anxiety disorders such as PTSD in the general population, although less is known about the impact on Veterans who have lived with PTSD for decades. This study assessed associations between social connectedness, physical function and self-reported change in PTSD symptoms among older Veterans specifically participating in Gerofit. DESIGN: Prospective clinical intervention. SETTING: Twelve sites of Veterans Affairs (VA) Gerofit exercise program across the United States. PARTICIPANTS: Three hundred and twenty one older Veteran Gerofit participants (mean age = 74) completed physical assessments and questionnaires regarding physical and emotional symptoms and their experience. MEASUREMENTS: Measures of physical function, including 30-second chair stands, 10-m and 6-min walk were assessed at baseline and 3 months; change in PTSD symptoms based on the Diagnostic Statistical Manual-5 (DSM-5) assessed by a self-report questionnaire; and social connection measured by the Relatedness Subscale of the Psychological Need Satisfaction in Exercise scale (PNSE) were evaluated after 3 months of participation in Gerofit. RESULTS: Ninety five (29.6%) Veterans reported PTSD. Significant improvement was noted in self-rated PTSD symptoms at 3 months (P < .05). Moderate correlation (r = .44) was found between social connectedness with other participants in Gerofit and PTSD symptom improvement for those Veterans who endorsed improvement (n = 59). All participants improved on measures of physical function. In Veterans who endorsed PTSD there were no significant associations between physical function improvement and PTSD symptoms. CONCLUSION: Veterans with PTSD that participated in Gerofit group exercise reported symptom improvement, and social connectedness was significantly associated with this improvement. In addition to physical health benefits, the social context of Gerofit may offer a potential resource for improving PTSD symptoms in older Veterans that warrants further study.

Education differentially contributes to cognitive reserve across racial/ethnic groups.

INTRODUCTION: We examined whether educational attainment differentially contributes to cognitive reserve (CR) across race/ethnicity. METHODS: A total of 1553 non-Hispanic Whites (Whites), non-Hispanic Blacks (Blacks), and Hispanics in the Washington Heights-Inwood Columbia Aging Project (WHICAP) completed structural magnetic resonance imaging. Mixture growth curve modeling was used to examine whether the effect of brain integrity indicators (hippocampal volume, cortical thickness, and white matter hyperintensity [WMH] volumes) on memory and language trajectories was modified by education across racial/ethnic groups. RESULTS: Higher educational attainment attenuated the negative impact of WMH burden on memory (ß = -0.03; 99% CI: -0.071, -0.002) and language decline (ß = -0.024; 99% CI:- 0.044, -0.004), as well as the impact of cortical thinning on level of language performance for Whites, but not for Blacks or Hispanics. DISCUSSION: Educational attainment does not contribute to CR similarly across racial/ethnic groups.

Potential Benefits of Physical Activity in MCI and Dementia.

Physical activity improves overall health and reduces the risk of many negative health outcomes and may be effective in improving cognition, independent functioning, and psychological health in older adults. Given the evidence linking physical activity with improvements in various aspects of health and functioning, interventions exploring pathways for decreasing risk of dementia in those with mild cognitive impairment (MCI) and improving outcomes for those with dementia are of critical importance. The present review highlights the work examining physical activity interventions in order to achieve a comprehensive understanding of the potential benefits of physical activity for individuals experiencing cognitive decline. The primary focus is on aerobic exercise as this is the main intervention in the literature. Our review supports the thesis that physical activity can promote healthy aging in terms of cognition, independent functioning, and psychological health for individuals experiencing cognitive decline. Specifically, physical activity improves cognition, especially executive functioning and memory in MCI, independent functioning in MCI and dementia, and psychological health in dementia. Given that benefits of physical activity have been observed across these domains, such interventions provide an avenue for preventing decline and/or mitigating impairment across several domains of functioning in older adults with MCI or dementia and may be recommended (and adjusted) for patients across a range of settings, including medical and mental health settings. Further implications for clinical intervention and future directions for research are discussed.

Prefrontal working memory activity predicts episodic memory performance: A neuroimaging study.

Working memory (WM) and long term memory (LTM) are different neuropsychological processes, although distinction between these domains is an area of debate. LTM is thought to rely on hippocampal circuitry. Cognitive neuroscience models imply that WM processing may at least partially support LTM within regions of the prefrontal cortex (PFC). We sought to determine the association between PFC based WM processing and LTM in the visuospatial domain. In contrast to prior work, we aimed to query if WM was involved in learning and free recall trials as measured by standard neuropsychological tests of LTM. Forty-three older adults (24 with a diagnosis of amnestic Mild Cognitive Impairment and 19 elderly controls) were included in the analysis. Patients completed a fMRI task of visuospatial maintenance WM in which they were required to match a previously studied complex shape with one of two probes. Extent of activity in the right PFC during the WM task was tabulated for each patient. Hippocampal volume was quantified from T1 scans. On a separate day patients completed neuropsychological testing, including the Brief Visuospatial Memory Test- Revised (BVMT-R), which includes learning trials (total recall), delayed free recall, and recognition. Right PFC activity was associated with performance on BVMT-R total recall and delayed recall. Results from multiple regression showed that PFC activity explained an additional 9 % of the variance in memory performance above right hippocampal volume. These findings suggest that PFC processing that supports WM (including stimuli maintenance, retrieval, and selection) are also involved in LTM learning and recall.

Progress and future challenges in aging and diversity research in the United States.

In 2016, the UC Davis Latino Aging Research Resource Center and UC Davis Alzheimer's Disease Center brought together experts from across the country to consolidate current knowledge and identify future directions in aging and diversity research. This report disseminates the research priorities that emerged from this conference, building on an earlier Gerontological Society of America preconference. We review key racial/ethnic differences in cognitive aging and dementia and identify current knowledge gaps in the field. We advocate for a systems-level framework for future research whereby environmental, sociocultural, behavioral, neuropathological, genetic, and psychometric levels of analysis are examined together to identify pathways and mechanisms that influence disparities. We then discuss steps to increase the recruitment and retention of racial/ethnic minorities in aging studies, as none of the recommendations will be possible without strong collaboration between racial/ethnic minority communities and researchers. This approach is consistent with the National Institute on Aging Health Disparities Research Framework.

Alterations to task positive and task negative networks during executive functioning in Mild Cognitive Impairment.

Poor executive functioning increases risk of decline in Mild Cognitive Impairment (MCI). Executive functioning can be conceptualized within the framework of working memory. While some components are responsible for maintaining representations in working memory, the central executive is involved in the manipulation of information and creation of new representations. We aimed to examine the neural correlates of these components of working memory using a maintenance working memory and visuospatial reasoning task. Twenty-five patients with amnestic MCI and 19 elderly controls (EC) completed functional MRI during reasoning and maintenance working memory tasks. In MCI, maintenance working memory was associated with hypoactivation of right frontoparietal regions and hyperactivation of left prefrontal cortex, coupled with attenuation of default mode network (DMN) relative to EC. During reasoning, MCI showed hypoactivation of parietal regions, coupled with attenuation of anterior DMN and increased deactivation of posterior DMN relative to EC. Comparing the reasoning task to the maintenance working memory task yields the central executive. In MCI, the central executive showed hypoactivation of right parietal lobe and increased deactivation of posterior DMN compared to EC. Consistent with prior work on executive functioning, MCI show different neural circuitry during visuospatial reasoning, including changes to both task positive frontoparietal regions, as well as to deactivation patterns within the DMN. Both hyperactivation of task positive networks and increased deactivation of DMN may be compensatory.

Cerebral metabolic correlates of attention networks in Alzheimer's Disease: A study of the Stroop.

Patients with Alzheimer's Disease (AD) show difficulties with attention. Cognitive neuroscience models posit that attention can be broken down into alerting, orienting, and executive networks. We used the Stroop Color-Word test to interrogate the neural correlates of attention deficits in AD. We hypothesized that the Word, Color, and Color-Word conditions of the Stroop would all tap into the alerting and orienting networks. The Color-Word condition would additionally tap into the executive network. A ratio of Color-Word to Color naming performance would isolate the executive network from the others. To identify the neural underpinnings of attention in AD we correlated performance on the Stroop with brain metabolic activity. Sixty-six patients with probable AD completed [18F] fluorodeoxyglucose PET scanning and neuropsychological testing. Analysis was conducted with SPM12 (p<0.001 uncorrected, extent threshold 50 voxels). Performance on the Word, Color, and Color-Word conditions directly correlated with metabolic rate in right inferior parietal lobules/intraparietal sulci. The Color-Word/Color ratio revealed associations with metabolic rate in right medial prefrontal cortex and insula/operculum. Overall findings were largely consistent with the hypothesized neuroanatomical substrates of the alerting, orienting, and executive networks. As such, attention deficits in AD reflect compromise to multiple large-scale networks.

Cortical Metabolic and Cognitive Correlates of Disorientation in Alzheimer's Disease.

Orientation to time, date, and place is commonly utilized in clinical settings to aid in diagnosis, staging, and monitoring of Alzheimer's disease (AD). This study aimed to identify the cerebral metabolic correlates of orientation in patients with AD, and the degree to which regions associated with orientation overlap with memory-related structures. Eighty-five patients with a diagnosis of probable AD underwent fluorodeoxyglucose positron emission tomography (FDG-PET) and neuropsychological testing. Orientation items from the Dementia Rating Scale and recognition performance from the Consortium to Establish a Registry for AD (CERAD) Word List Learning test were correlated with cerebral glucose metabolism. Post-hoc analyses examined neuropsychological predictors of orientation. Better orientation performance related to greater cerebral metabolism in the bilateral middle-inferior temporal lobes, bilateral middle-posterior cingulate, left angular gyrus, and left middle occipital gyrus. In comparison, higher CERAD recognition discriminability score was associated with greater metabolic activity in left medial temporal lobe regions including the hippocampal and parahippocampal gyri, and the left fusiform gyrus. Post-hoc behavioral analyses revealed multiple cognitive functions to be related to orientation, including list learning, recognition memory, visuospatial functioning, attention, and language. Findings from the present study suggest that disorientation in AD results from dysfunction of a network of structures and cognitive abilities commonly found to be implicated in AD. The study supports the notion that memory is necessary but not sufficient for successful orientation.

Cholinergic Receptor Binding in Alzheimer Disease and Healthy Aging: Assessment In Vivo with Positron Emission Tomography Imaging.

OBJECTIVE: To compare regional nicotinic cholinergic receptor binding in older adults with Alzheimer disease (AD) and healthy older adults in vivo and to assess relationships between receptor binding and clinical symptoms. METHODS: Using cross-sectional positron emission tomography (PET) neuroimaging and structured clinical assessment, outpatients with mild to moderate AD (N = 24) and healthy older adults without cognitive complaints (C group; N = 22) were studied. PET imaging of α4ß2* nicotinic cholinergic receptor binding using 2-[18F]fluoro-3-(2(S)azetidinylmethoxy)pyridine (2FA) and clinical measures of global cognition, attention/processing speed, verbal memory, visuospatial memory, and neuropsychiatric symptoms were used. RESULTS: 2FA binding was lower in the AD group compared with the C group in the medial thalamus, medial temporal cortex, anterior cingulate, insula/opercula, inferior caudate, and brainstem (p < 0.05, corrected cluster), but binding was not associated with cognition. The C group had significant inverse correlations between 2FA binding in the thalamus (left: rs = -0.55, p = 0.008; right: rs = -0.50, p = 0.02; N = 22) and hippocampus (left: rs = -0.65, p = 0.001; right: rs = -0.55, p = 0.009; N = 22) and the Trails A score. The AD group had inverse correlation between 2FA binding in anterior cingulate (left: rs = -0.50, p = 0.01; right: rs = -0.50, p = 0.01; N = 24) and Neurobehavioral Rating Scale agitation/disinhibition factor score. CONCLUSION: Cholinergic receptor binding is reduced in specific brain regions in mild to moderate AD and is related to neuropsychiatric symptoms. Among healthy older adults, lower receptor binding may be associated with slower processing speed. Cholinergic receptor binding in vivo may reveal links to other key brain changes associated with aging and AD and may provide a potential molecular treatment target.

18F-Fluorodeoxyglucose Positron Emission Tomography Cortical Metabolic Activity Associated with Distinct Agitation Behaviors in Alzheimer Disease.

OBJECTIVE: This study aimed to investigate the neurobiologic correlates of two distinct clusters of agitation symptoms to identify the unique biologic substrates underlying agitated behaviors. METHODS: Eighty-eight outpatients with mild to moderate Alzheimer disease (AD) were recruited from the VA Greater Los Angeles Healthcare System Geropsychiatry Outpatient Program. A cross-sectional investigation was conducted of the relationship between cerebral glucose metabolism measured via 18F-fluorodeoxyglucose positron emission tomography and agitated symptoms from the Neuropsychiatric Inventory (NPI) in patients with AD. Two empirically derived clusters of agitation symptoms were investigated: an Agitation factor comprising agitation/aggression and irritability/lability items of the NPI, and a Behavioral Dyscontrol factor comprising elation/euphoria, disinhibition, aberrant motor behavior, sleep, and appetite items of the NPI. Mean cerebral metabolism for patients who scored positively on each of the two factors was compared with mean cerebral metabolism for those who did not. RESULTS: Patients with AD who scored positively on the Agitation factor showed reduced glucose metabolism of the right temporal, right frontal, and bilateral cingulate cortex. In contrast, the Behavioral Dyscontrol factor did not show specific neurobiologic correlates. CONCLUSION: Symptoms encompassed within the Agitation factor have distinct neurobiologic underpinnings. The precipitants, course, and outcomes related to these symptoms may be unique from other neuropsychiatric symptoms characteristic of AD. Special attention to treatment of agitated behaviors involving anger, aggressiveness, hostility, and irritability/emotional lability is warranted, because they appear to reflect a clinically relevant symptom cluster with unique underlying neurobiologic correlates.

The functional neuroanatomy of verbal memory in Alzheimer's disease: [18F]-Fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) correlates of recency and recognition memory.

INTRODUCTION: The objective of this study was to distinguish the functional neuroanatomy of verbal learning and recognition in Alzheimer's disease (AD) using the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Word Learning task. METHOD: In 81 Veterans diagnosed with dementia due to AD, we conducted a cluster-based correlation analysis to assess the relationships between recency and recognition memory scores from the CERAD Word Learning Task and cortical metabolic activity measured using [18F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET). RESULTS: AD patients (Mini-Mental State Examination, MMSE mean = 20.2) performed significantly better on the recall of recency items during learning trials than of primacy and middle items. Recency memory was associated with cerebral metabolism in the left middle and inferior temporal gyri and left fusiform gyrus (p < .05 at the corrected cluster level). In contrast, recognition memory was correlated with metabolic activity in two clusters: (a) a large cluster that included the left hippocampus, parahippocampal gyrus, entorhinal cortex, anterior temporal lobe, and inferior and middle temporal gyri; (b) the bilateral orbitofrontal cortices (OFC). CONCLUSIONS: The present study further informs our understanding of the disparate functional neuroanatomy of recency memory and recognition memory in AD. We anticipated that the recency effect would be relatively preserved and associated with temporoparietal brain regions implicated in short-term verbal memory, while recognition memory would be associated with the medial temporal lobe and possibly the OFC. Consistent with our a priori hypotheses, list learning in our AD sample was characterized by a reduced primacy effect and a relatively spared recency effect; however, recency memory was associated with cerebral metabolism in inferior and lateral temporal regions associated with the semantic memory network, rather than regions associated with short-term verbal memory. The correlates of recognition memory included the medial temporal lobe and OFC, replicating prior studies.

Glucose levels during life and neuropathologic findings at autopsy among people never treated for diabetes.

We evaluated associations between glucose and dementia-related neuropathologic findings among people without diabetes treatment history to elucidate mechanisms of glucose's potential effect on dementia. We used glucose and hemoglobin A1c values to characterize glucose exposures over 5 years before death (primary) and age bands from 55-59 through 80-84 (secondary). Autopsy evaluations included Braak stage for neurofibrillary tangles, Consortium to Establish a Registry for Alzheimer's Disease grade for neuritic plaques, macroscopic infarcts including lacunar infarcts, Lewy bodies, cerebral microinfarcts, and hippocampal sclerosis. Of 529 who came to autopsy, we included 430 with no history of diabetes treatment. We found no associations between glucose levels and Braak stage or Consortium to Establish a Registry for Alzheimer's Disease grade. There was a suggestion of a relationship between glucose and hippocampal sclerosis, although this was inconsistent across analyses. There was higher risk of Lewy bodies in substantia nigra and locus ceruleus with higher glucose levels in age band analyses. We did not find interactions between glucose levels, neuropathologic findings, and dementia. The mechanism by which glucose may impact dementia risk is still unknown.

An advanced white matter tract analysis in frontotemporal dementia and early-onset Alzheimer's disease.

Cortical and subcortical nuclei degenerate in the dementias, but less is known about changes in the white matter tracts that connect them. To better understand white matter changes in behavioral variant frontotemporal dementia (bvFTD) and early-onset Alzheimer's disease (EOAD), we used a novel approach to extract full 3D profiles of fiber bundles from diffusion-weighted MRI (DWI) and map white matter abnormalities onto detailed models of each pathway. The result is a spatially complex picture of tract-by-tract microstructural changes. Our atlas of tracts for each disease consists of 21 anatomically clustered and recognizable white matter tracts generated from whole-brain tractography in 20 patients with bvFTD, 23 with age-matched EOAD, and 33 healthy elderly controls. To analyze the landscape of white matter abnormalities, we used a point-wise tract correspondence method along the 3D profiles of the tracts and quantified the pathway disruptions using common diffusion metrics - fractional anisotropy, mean, radial, and axial diffusivity. We tested the hypothesis that bvFTD and EOAD are associated with preferential degeneration in specific neural networks. We mapped axonal tract damage that was best detected with mean and radial diffusivity metrics, supporting our network hypothesis, highly statistically significant and more sensitive than widely studied fractional anisotropy reductions. From white matter diffusivity, we identified abnormalities in bvFTD in all 21 tracts of interest but especially in the bilateral uncinate fasciculus, frontal callosum, anterior thalamic radiations, cingulum bundles and left superior longitudinal fasciculus. This network of white matter alterations extends beyond the most commonly studied tracts, showing greater white matter abnormalities in bvFTD versus controls and EOAD patients. In EOAD, network alterations involved more posterior white matter - the parietal sector of the corpus callosum and parahipoccampal cingulum bilaterally. Widespread but distinctive white matter alterations are a key feature of the pathophysiology of these two forms of dementia.