Exercise engagement drives changes in cognition and cardiorespiratory fitness after 8 weeks of aerobic training in sedentary aging adults at risk of cognitive decline

BackgroundWith our aging population, many individuals are at risk of developing age-related cognitive decline. Physical exercise has been demonstrated to enhance cognitive performance in aging adults. This study examined the effects of 8 weeks of aerobic exercise on cognitive performance and cardiorespiratory fitness in sedentary aging adults at risk for cognitive decline.MethodsFifty-two participants (age 62.9 ± 6.8, 76.9% female) engaged in eight weeks of moderate-to high-intensity exercise (19 in-person, 33 remotely). Global cognition was measured by the Repeatable Battery for the Assessment of Neuropsychological Status, the Delis-Kaplan Executive Function System, and the Digit Span subtest of the Wechsler Adult Intelligence Scale (WAIS) Fourth Edition. Cardiorespiratory fitness was measured via heart rate recovery at minute 1 (HRR1) and 2 (HRR2), and exercise engagement (defined as percent of total exercise time spent in the prescribed heart rate zone). We measured pre and post changes using paired t-tests and mixed effects models, and investigated the association between cardiorespiratory and cognitive performance using multiple regression models. Cohen's d were calculated to estimate effect sizes.ResultsOverall, 63.4 % of participants demonstrated high engagement (≥ 70% total exercise time spent in the prescribed heart rate zone). There were significant pre-post improvements in verbal fluency and verbal memory, and a significant decrement in working memory, but these were associated with small effect sizes (Cohen's d <0.5). Concerning cardiorespiratory fitness, there was a pre-to-post significant improvement in HRR1 (p = 0.01, d = 0.30) and HRR2 (p < 0.001, d = 0.50). Multiple regressions revealed significant associations between cardiorespiratory and cognitive performance, but all were associated with small effect sizes (Cohen's d < 0.5). Interestingly, there were significant between-group differences in exercise engagement (all p < 0.001), with remote participants demonstrating greater exercise engagement than in-person participants.ConclusionImprovements in cognition and cardiorespiratory fitness were observed after 8 weeks of moderate to high-intensity exercise in aging adults. These results suggest that committing to a regular exercise regimen, even for a brief two-month period, can promote improvements in both cardiorespiratory fitness and cognitive performance, and that improvements are driven by exercise engagement

HEALTH PROMOTION TO PREVENT AND REDUCE COGNITIVE DECLINE IN LATINOS LIVING WITH HIV/AIDS

Older Latinos living with HIV (LWH) are at increased risk for earlier onset of aging-related cognitive decline. HIV-related cognitive impairments are observed in several domains including memory, reasoning/executive functioning, and speed of processing. Depression, a known neurocognitive risk, has been reported at five times the level among older Latinos LWH than in the general population, and older Latinos LWH are more likely to be sedentary, and not as actively engaged in pursuing changes in physical activity compared to their non-Latino White counterparts. Thus, this is a population that is particularly vulnerable to cognitive decline due to multiple risk factors. The aim of this study is to assess feasibility, acceptability, and preliminary intervention effects on cognition of the Happy Older Latinos are Active (HOLA) health promotion intervention. Thirty Latinos living with HIV with a mean age of 61.6 years (SD=6.1) were enrolled in a pilot single-arm trial. Participants were assessed at two time points on measures of cognitive and psychosocial functioning as well as biomarkers of cognition. In 7 months, we met our enrollment target with <5% of eligible participants refusing participation. Participants attended over 70% of sessions and 3 participants were lost to follow up. These results indicate that HOLA is an innovative health promotion program that is uniquely tailored to address the multiple concerns that are prevalent in this community in a non-stigmatizing and culturally acceptable manner

A Teleneuropsychology Protocol for the Cognitive Assessment of Older Adults During COVID-19

The Coronavirus Disease 2019 (COVID-19) pandemic prompted the need for a teleneuropsychology protocol for the cognitive assessment of older adults, who are at increased risk for both COVID-19 and dementia. Prior recommendations for teleneuropsychological assessment did not consider many of the unique challenges posed by COVID-19. The field is still in need of clear guidelines and standards of care for the assessment of older adults under the current circumstances. Advantages of teleneuropsychological assessment during the COVID-19 pandemic include reduced risk of contracting the virus, eliminating travel time and reducing cost, and more rapid access to needed services. Challenges include disparities in technology access among patients, reduced control over the testing environment, impeded ability to make behavioral observations, and limited research on valid and reliable cognitive assessment measures. The aim of this perspective review is to propose a teleneuropsychological protocol to facilitate neuropsychological assessment utilizing a virtual platform. The proposed protocol has been successful with our clinical and research populations and may help neuropsychologists implement teleneuropsychology services without compromising validity or reliability. However, there is increasing need for research on teleneuropsychological assessment options for both clinical and research purposes

Semantic intrusion errors as a function of age, amyloid, and volumetric loss: a confirmatory path analysis

To examine the direct and indirect effects of age, APOE ϵ4 genotype, amyloid positivity, and volumetric reductions in AD-prone brain regions as it relates to semantic intrusion errors reflecting proactive semantic interference (PSI) and the failure to recover from proactive semantic interference (frPSI) on the Loewenstein-Acevedo Scales of Semantic Interference and Learning (LASSI-L), a cognitive stress test that has been consistently more predictive of preclinical and prodromal Alzheimer's disease (AD) than traditional list-learning tests. Cross-sectional study. 1Florida Alzheimer's Disease Research Center baseline study. Two-hundred and twelve participants with Mini-Mental State Examination (MMSE) score above 16 and a broad array of cognitive diagnoses ranging from cognitively normal (CN) to dementia, of whom 58% were female, mean age of 72.1 (SD 7.9). Participants underwent extensive clinical and neuropsychological evaluations, MR and amyloid Positron Emission Tomography/Computer/Computer Tomography (PET/CT) imaging, and analyses of APOE ϵ4 genotype. Confirmatory path analyses were conducted in the structural equation modeling framework that estimated multiple equations simultaneously while controlling for important covariates such as sex, education, language of evaluation, and global cognitive impairment. Both amyloid positivity and decreased brain volumes in AD-prone regions were directly related to LASSI-L Cued B1 and Cued B2 intrusions (sensitive to PSI and frPSI effects) even after controlling for covariates. APOE ϵ4 status did not evidence direct effects on these LASSI-L cognitive markers, but rather exerted their effects on amyloid positivity, which in turn related to PSI and frPSI. Similarly, age did not have a direct relationship with LASSI-L scores, but exerted its effects indirectly through amyloid positivity and volumes of AD-prone brain regions. Our study provides insight into the relationships among age, APOE ϵ4, amyloid, and brain volumetric reductions as it relates to semantic intrusion errors. The investigation expands our understanding of the underpinnings of PSI and frPSI intrusions in a large cohort

The Cognitive Stress Test (CST): An Innovative Tool to Differentiate Cognitively Unimpaired (CU) Older Adults from those with Pre‐Mild Cognitive Impairment (Pre‐MCI) and Amnestic MCI (aMCI)

Background The CST is a novel assessment that was designed to measure cognitive changes during preclinical and prodromal stages of AD, that include aMCI and PreMCI, where deficits do not meet MCI. The CST employs semantically competing word lists to measure the impact of semantic interference, failure to recover from proactive semantic interference (frPSI), and its persistent effects, despite multiple trials. We hypothesized that frPSI deficits on the CST would be persistent in pre‐MCI and aMCI groups when compared to cognitively unimpaired (CU) controls. Method 50 aMCI, 31 pre‐MCI, and 69 CU elders were administered the CST. Participants were presented with List A (18 semantically related words: occupations, household items, or transportation methods) for three initial learning trials, followed by three learning trials of List B, a categorically similar wordlist, to examine PSI and frPSI. Retroactive Semantic Interference (RSI) was assessed by using category cues to elicit recall of List A targets, followed by an additional learning trial to examine failure to recover from RSI (frRSI). Result Significant differences were observed between all diagnostic groups across CST Cued Recall trials that measure maximum learning, PSI, frPSI, and persistent frPSI. PreMCI and aMCI participants experienced deficits in learning List B despite two additional opportunities; a deficit that was observed even after adjusting for initial learning strength. Older adults with greater risk (preMCI and aMCI) performed similarly on indices that measures PSI, frPSI, and persistent frPSI as compared to controls. There were differences in RSI among CU and aMCI groups yet measuring frRSI did not differentiate groups. aMCI participants made more semantic intrusion errors on recall trials that cued List B words. Pre‐MCI and CU made a similar number of intrusion errors. Conclusion The CST extends our work by assessing persistent effects of frPSI, which have been shown to predict neurodegenerative progression and have been associated with multiple biomarkers of AD. The finding that persistent frPSI could differentiate CU from preMCI groups is a promising indicator that semantic interference deficits persist in older adults that present a heightened risk for progression to dementia and is worthy of further research

A Brief Version of the LASSI-L Detects Prodromal Alzheimer's Disease States

The Loewenstein-Acevedo Scales for Semantic Interference and Learning (LASSI-L) is an increasingly utilized cognitive stress test designed to identify early cognitive changes associated with incipient neurodegenerative disease. To examine previously derived cut-points for cognitively unimpaired older adults that were suggestive of performance impairment on multiple subscales of the LASSI-L. These cut-points were applied to a new sample of older adults who were cognitive healthy controls (HC: n = 26) and those on the Alzheimer's disease (AD) continuum from early stage mild cognitive impairment (EMCI: n = 28), late stage MCI (LMCI: n = 18) to mild AD (AD: n = 27). All participants were administered the LASSI-L. All cognitively impaired participants were PET amyloid positive which likely reflects underlying AD neuropathology, while cognitively normal counterparts were deemed to have amyloid negative scans. There was a monotonic relationship between the number of deficits on LASSI-L subscales and independent classification of study groups with greater severity of cognitive impairment. Importantly, taken together, impairment on maximum learning ability and measures of proactive semantic interference (both reflected by cued recall and intrusion errors) correctly classified 74.1% of EMCI, 94.4% of LMCI, and 96.3% of AD. Only 7.7% of HC were incorrectly classified as having impairments. A modest number of LASSI-L subscales taking approximately 8 minutes to administer, had excellent discriminative ability using established cut-offs among individuals with presumptive stages of AD. This has potential implications for both clinical practice and clinical research settings targeting AD during early prodromal stages

A-144 A Cross-Validation Study of Memory and Non-Memory Neuropsychology Measures with Spanish-Speaking Older Adults

Abstract Objective: To evaluate the clinical utility of the Spanish versions of memory vs. non-memory instruments in a Spanish-speaking sample; specifically, the comparative performance for the English versions in amnestic MCI (aMCI) and cognitively unimpaired (CU) elders. Method: 255 Non-Hispanic English speakers (NH-ES; 157 CU; 98 aMCI) and 201 Hispanic Spanish speakers (H-SS; 103 CU; 98 aMCI) were classified using the Clinical Dementia Rating Scale and a validated culturally fair test. ANCOVA procedures were used to test for differences between four groups across languages adjusting for age, sex, and education for memory (e.g., Hopkins Verbal Learning Test-HVLT-R; NACC Logical Memory) and non-memory measures (e.g., Trail-Making Test A-B, Category and Phonemic Fluency). Results: For memory measures, CU older adults were statistically differentiated from aMCI counterparts regardless of language. No significant differences between H-SS aMCI and NH-ES aMCI groups’ on HVLT-R and NACC story passages immediate/delayed conditions. No significant differences found between H-SS CU and NH-ES CU on memory indices. Conversely, Bonferroni corrected means (p<.05) revealed that even after adjustment for demographic covariates, ES CU outperformed H-SS CU counterparts on Trails A-B, and Category/Phonemic Fluencies. NH-ES aMCI groups scored better than H-SS aMCI on Trails B. Conclusions: Results indicate that memory measures experience less bias when employed among different linguistic/cultural groups regardless of cognitive status. In contrast, CU H-SS groups scored lower on all non-memory measures. Factors that lead to potential bias, particularly among CU are discussed. Trails-B evidenced bias for both Hispanic CU and MCI, making this a measure that requires the judicious use of appropriate norms

Barriers and Best Practices in Disclosing a Dementia Diagnosis: A Clinician Interview Study

The vast majority of individuals with dementia want to receive a diagnosis. Research suggests, however, that only a fraction of individuals with dementia receive a diagnosis and patients and families often feel the information is poorly explained. We thus aimed to assess clinician-reported barriers to dementia disclosure and recommendations for giving a dementia diagnosis. To accomplish this, we performed telephone interviews with 15 clinicians from different specialties using a semi-structured interview guide. Transcripts were analyzed thematically. Clinician-reported barriers fit 3 categories: patient and caregiver-related barriers, clinician-related barriers, and barriers related to the triadic interaction. Patient and caregiver-related barriers included lack of social support, misunderstanding the diagnosis, and denial. Clinician barriers included difficulty giving bad news, difficulty communicating uncertainty, and lack of time. Triadic interaction barriers included challenges meeting multiple goals or needs and family requests for non-disclosure. Recommendations for best practice included for clinicians to foster relationships, educate patients and family, and take a family-centered approach. Clinicians described recommendations for fostering relationships such as using empathic communication and developing and maintaining connection. Educating patients and families included tailoring communication, explaining how the diagnosis was reached, and following up. Family approaches included meeting with family members prior to delivering the diagnosis and involving the caregiver in the discussion. Findings may inform updated recommendations for best practices when communicating a dementia diagnosis

Clinician approaches to communicating a dementia diagnosis: An interview study

Individuals with cognitive impairment and their families place a high value on receiving a dementia diagnosis, but clinician approaches vary. There is a need for research investigating experiences of giving and receiving dementia diagnoses. The current study aimed to investigate clinician approaches to giving dementia diagnoses as part of a larger study investigating patient, caregiver, and clinician experiences during the diagnosis encounter. Investigators conducted telephone interviews with Florida-based clinicians who give dementia diagnoses either rarely or commonly. Interviews employed a semi-structured interview guide querying communication practices used by clinicians when giving dementia diagnoses and how clinicians learned to give dementia diagnoses. Investigators used a descriptive qualitative design to conduct a thematic analysis of data. Fifteen Florida-based clinicians participated, representing diverse backgrounds related to gender, race/ethnicity, specialty, and practice setting. Participants reported using patient- and family-centered communication practices including checking patient understanding, communicating empathically, and involving family members. Some clinicians explicitly asked patients and/or family members about their preferences regarding diagnosis disclosure; many clinicians tailored their disclosure based on patient and family characteristics or reactions. Some clinicians reported using specific diagnoses, while others used general terms such as "memory disorder." Clinicians reported positively framing information, including instilling hope, focusing on healthy behaviors, and discussing symptom management. Finally, clinicians provided patient/family education and arranged follow up. Clinicians reported learning approaches to dementia diagnosis disclosure through formal training and self-education. Diverse Florida-based clinicians described dementia disclosure practices largely consistent with published guidance, but clinicians varied on approaches relating to soliciting patient disclosure preferences and terminology used. Clinicians caring for diverse populations described that cultural background affects the disclosure process, but more research is needed regarding this finding and best practices for individuals from different backgrounds