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Objectives The objectives of this project were to: (1) examine the relationship between the number of biological children and hippocampal-dependent cognitive performance among older African American women and (2) determine the influence of socioeconomic status (i.e. age, education, marital status, median household income), if any, on this relationship. Methods A total of 146 cognitively unimpaired African American women aged 60 and older were recruited from the greater Newark area and reported their number of biological children, marital status, educational level, and age. We retrieved median household income from census tract data based on the participants' addresses. Participants' cognitive performance was assessed using the Rey Auditory Verbal Learning Test (RAVLT) long delay recall and a Rutgers generalization task (Concurrent Discrimination and Transfer Task). Results As the number of biological children a woman has had increases, the number of generalization errors also increased, indicating poorer hippocampal-dependent cognitive performance when controlling for age, education, marital status, and median household income. There was no significant relationship between the number of children and performance on a standardized neuropsychological measure of episodic memory (RAVLT), although education was a significant covariate. Discussion Generalization tasks may better capture early changes in cognitive performance in older African American women who have had children than standardized neuropsychological assessments. This finding may be explained by the fluctuations in estrogen associated with having children. Future studies should explore how these findings can be applied to protecting cognitive function and preventing Alzheimer's disease in older African American women who have had children. [ABSTRACT FROM AUTHOR]

African Americans experience higher incidence and prevalence of Alzheimer's disease (AD). Yet, they continue to be underrepresented in AD research, limiting the ability to generalize findings to the increasingly diverse US population. To reduce AD disparities, targeted efforts are needed to increase the representation of African Americans in AD research. This mini review identified evidence-based strategies that increased research participation among older African Americans. Four recruitment strategies emerged from eight published peer-reviewed studies that directly evaluated the effectiveness of strategies aimed at increasing the number of African American participants in Alzheimer's research. The strategies include community outreach and education, face-to-face discussions, remote access, and referral and partnership with local organizations. Across different locations, these strategies increased the number of African Americans enrolled into AD research, the number of people that signed up to donate their brains for AD research upon death, and the knowledge and perception of AD in the communities. Targeted efforts are effective in increasing AD research participation among older African Americans, especially when combined with approaches that emphasize transparency and mutual trust and involve the community as stakeholders in the research process. [ABSTRACT FROM AUTHOR]

Hypertension disproportionately affects African Americans and is a risk factor for Alzheimer's disease (AD). We investigated the relationship of blood pressure (BP) with medial temporal lobe (MTL) dynamic network flexibility (a novel AD biomarker) and cognitive generalization in older African Americans. In a cross‐sectional study, 37 normotensive (systolic BP <130 mmHg, 82.5% F, 64.4 ± 4.9 years; 14.3 ± 2.1 years of education) versus 79 hypertensive (systolic BP ≥130 mmHg, 79.5% F, 66.8 ± 4.1 years; 14.0 ± 0.2 years of education) participants were enrolled. All participants completed a 10‐min resting‐state functional magnetic resonance imaging scan to assess MTL dynamic network flexibility and two generalization tasks to assess cognition. Anthropometrics and aerobic fitness (via 6‐min walk test) were also determined. There was no difference in BMI (29.7 ± 6.4 vs. 31.9 ± 6.3 kg/m2, p = 0.083) or aerobic fitness (15.5 ± 2.6 vs. 15.1 ± 2.6 mL/kg/min; p = 0.445) between normotensive and hypertensive groups. However, normotensive participants had higher MTL dynamic network flexibility compared to hypertensive participants (0.42 ± 0.23 vs. 0.32 ± 0.25 mL, p = 0.040), and this was associated with higher mean arterial blood pressure (r = −0.21, p = 0.036). Therefore, hypertensive older African Americans demonstrated lower MTL dynamic network flexibility compared to their normotensive counterparts independent of BMI and aerobic fitness. Further studies are required to determine how blood pressure mediates AD risk in African Americans. [ABSTRACT FROM AUTHOR]

Introduction: African Americans are two to three times more likely to be diagnosed with Alzheimer’s disease (AD) compared to White Americans. Exercise is a lifestyle behavior associated with neuroprotection and decreased AD risk, although most African Americans, especially older adults, perform less than the recommended 150  min/week of moderate-to-vigorous intensity exercise. This article describes the protocol for a Phase III randomized controlled trial that will examine the effects of cardio-dance aerobic exercise on novel AD cognitive and neural markers of hippocampal-dependent function (Aims #1 and #2) and whether exercise-induced neuroprotective benefits may be modulated by an AD genetic risk factor, ABCA7 rs3764650 (Aim #3). We will also explore the effects of exercise on blood-based biomarkers for AD. Methods and analysis: This 6-month trial will include 280 African Americans (≥  60  years), who will be randomly assigned to 3  days/week of either: (1) a moderate-to-vigorous cardio-dance fitness condition or (2) a low-intensity strength, flexibility, and balance condition for 60  min/session. Participants will complete health and behavioral surveys, neuropsychological testing, saliva and venipuncture, aerobic fitness, anthropometrics and resting-state structural and functional neuroimaging at study entry and 6  months. Discussion: Results from this investigation will inform future exercise trials and the development of prescribed interventions that aim to reduce the risk of AD in African Americans. [ABSTRACT FROM AUTHOR]

Introduction: Excess body weight and Alzheimer's disease (AD) disproportionately affect older African Americans. While mid-life obesity increases risk for AD, few data exist on the relationship between late-life obesity and AD, or how obesity-based and genetic risk for AD interact. Although the APOE-ε4 allele confers a strong genetic risk for AD, it is unclear if late-life obesity poses a greater risk for APOE-ε4 carriers compared to non-carriers. Here we assessed: (1) the influence of body mass index (BMI) (normal; overweight; class 1 obese; ≥ class 2 obese) on cognitive and structural MRI measures of AD risk; and (2) the interaction between BMI and APOE-ε4 in older African Americans. Methods: Seventy cognitively normal older African American participants (Mage = 69.50 years; MBMI = 31.01 kg/m²; 39% APOE-ε4 allele carriers; 86% female) completed anthropometric measurements, physical assessments, saliva collection for APOE-ε4 genotyping, cognitive testing, health and lifestyle questionnaires, and structural neuroimaging [volume/surface area (SA) for medial temporal lobe subregions and hippocampal subfields]. Covariates included age, sex, education, literacy, depressive symptomology, and estimated aerobic fitness. Results: Using ANCOVAs, we observed that individuals who were overweight demonstrated better hippocampal cognitive function (generalization of learning: a sensitive marker of preclinical AD) than individuals with normal BMI, p = 0.016, ηp2 = 0.18. However, individuals in the obese categories who were APOE-ε4 noncarriers had larger hippocampal subfield cornu Ammonis region 1 (CA1) volumes, while those who were APOE-ε4 carriers had smaller CA1 volumes, p = 0.003, ηp² = 0.23. Discussion: Thus, being overweight by BMI standards may preserve hippocampal function, but obesity reduces hippocampal structure and function in older African Americans with the APOE-ε4 Alzheimer's disease risk allele. [ABSTRACT FROM AUTHOR]

Background: Both sleep deficiencies and Alzheimer's disease (AD) disproportionately affect older African Americans. Genetic susceptibility to AD further compounds risk for cognitive decline in this population. Aside from APOE ɛ4, ABCA7 rs115550680 is the strongest genetic locus associated with late-onset AD in African Americans. While sleep and ABCA7 rs115550680 independently influence late-life cognitive outcomes, we know too little about the interplay between these two factors on cognitive function. Objective: We investigated the interaction between sleep and ABCA7 rs115550680 on hippocampal-dependent cognitive function in older African Americans. Methods: One-hundred fourteen cognitively healthy older African Americans were genotyped for ABCA7 risk (n = 57 carriers of risk "G" allele; n = 57 non-carriers), responded to lifestyle questionnaires, and completed a cognitive battery. Sleep was assessed via a self-reported rating of sleep quality (poor, average, good). Covariates included age and years of education. Results: Using ANCOVA, we found that carriers of the risk genotype who reported poor or average sleep quality demonstrated significantly poorer generalization of prior learning—a cognitive marker of AD—compared to their non-risk counterparts. Conversely, there was no genotype-related difference in generalization performance in individuals who reported good sleep quality. Conclusion: These results indicate that sleep quality may be neuroprotective against genetic risk for AD. Future studies employing more rigorous methodology should investigate the mechanistic role of sleep neurophysiology in the pathogenesis and progression of AD associated with ABCA7. There is also need for the continued development of non-invasive sleep interventions tailored to racial groups with specific AD genetic risk profiles. [ABSTRACT FROM AUTHOR]

Objectives: Because African Americans are at elevated risk for cognitive decline and Alzheimer's disease, it is important to understand which health and lifestyle factors are most important for reducing this risk. Obesity and poor sleep quality are common in lower-income, urban African Americans and have been linked to cognitive decline in older age. Fortunately, increasing aerobic fitness via regular exercise can improve cognitive function. This study sought to (1) examine the cross-sectional relationship between aerobic fitness and cognitive function in older African Americans, and (2) determine whether body mass index and sleep quality moderated the relationship between aerobic fitness and cognition. Design: 402 older African Americans, ages 60–90 (84% female, mean education level = 14 years) completed neuropsychological testing, computerized behavioral tasks, physical performance measures, and health and lifestyle questionnaires. Hierarchical linear regressions were performed to determine associations between aerobic fitness and cognition and whether body mass index and sleep quality moderate the fitness-cognition relationship while controlling for age, sex, education, depressive symptoms, and literacy. Results: Higher aerobic fitness levels were significantly associated with better executive function. The relationships between fitness and hippocampal-dependent cognitive functions (learning and memory, generalization) were attenuated in those who are obese (body mass index ≥ 30 kg/m2) or rated their sleep quality as poor, ps <.05. Conclusion: Our results suggest that while exercise and associated improvements in aerobic fitness are key for improved cognition, these benefits are maximized in those who maintain low body weight and get sufficient, high quality sleep. Exercise programs for older African Americans will be most effective if they are integrated with education programs that emphasize healthy eating, weight control, and sleep hygiene and conceptualize individuals as part of their broader social and environmental context. [ABSTRACT FROM AUTHOR]

The current study sought to determine the influence of initial sleep quality and body mass index on the cognitive and mood outcomes of a community-based cardio-dance exercise program. Thirty-two older African Americans who participated in a 5-month cardio-dance exercise program were propensity-matched to 32 no-contact controls. Participants completed neuropsychological tests of attention, executive function, and memory and a self-reported depression measure at baseline and post-test. Among exercise participants, we observed significant improvements in depression (baseline = 6.16 ± 5.54, post-test = 4.66 ± 4.89, η p 2 =. 12 , p =.009) and attention (baseline = 40.53 ± 14.01, post-test = 36.63 ± 13.29, η p 2 =. 12 , p =.009) relative to controls. Improvements in executive function and attention were most pronounced among exercise participants with poor sleep quality (baseline = 7.71 ± 1.25, post-test = 8.29 ± 2.06, η p 2 =. 41 , p =.04) and with obesity (baseline = 38.05 ± 12.78, post-test = 35.67 ± 13.82, η p 2 =. 30 , p =.001), respectively. This study provides novel evidence that exercise has the potential to improve depression in older African Americans. For those with poor sleep quality or obesity, exercise can also improve some cognitive outcomes. [ABSTRACT FROM AUTHOR]

Auditory processing predicts cognitive decline, including dementia, in older adults. Auditory processing involves the understanding, interpretation, and communication of auditory information. Cognition is linked to auditory processing; however, it is disputed whether auditory processing is a separate construct distinct from cognition. The purpose of this study was to determine if auditory processing is distinct from cognition in older adults. Participants completed 14 cognitive and auditory processing assessments. Assessments were subjected to exploratory factor analysis with principal components extraction and varimax rotation with Kaiser normalisation. Study sample: 213 community-dwelling older adults (M = 71.39 years, 57% female, 93% Caucasian, M = 16 years education) with and without mild cognitive impairment (MCI) participated. Four factors were identified, explaining 66.3% of the total variance: (1) executive functions, visual processing speed, and dichotic auditory processing, (2) auditory processing of degraded speech, (3) memory, and (4) auditory temporal processing of nonspeech. Two domains of auditory processing (processing degraded speech and temporal processing) account for unique variance to which cognitive measures are not sensitive, while measures of auditory dichotic processing appear to be tapping similar abilities as measures of cognition. Older adults who perform poorly on dichotic measures should be screened for cognitive impairment. [ABSTRACT FROM AUTHOR]

Objective: This study aims to examine indicators of crash risk longitudinally in older adults (n = 486). Method: This study applied secondary data analyses of the 10 years of follow-up for the ACTIVE study combined with state-recorded crash records from five of the six participating sites. Cox proportional hazards models were first used to examine the effect of each variable of interest at baseline after controlling for miles driven and then to assess the three cognitive composites as predictors of time to at-fault crash in covariate-adjusted models. Results: Older age, male sex, and site location were each predictive of higher crash risk. Additionally, worse scores on the speed of processing cognitive composite were associated with higher crash risk. Discussion: Results support previous findings that both age and male sex are associated with higher crash risk. Our significant finding of site location could be attributed to the population density of our testing sites and transportation availability. [ABSTRACT FROM AUTHOR]

Purpose: The aims of the study were to compare the Cognitive Self-Report Questionnaire (CSRQ; Spina, Ruff, & Mahncke, 2006) Hearing and Cognitive subscale ratings among older adults with and without probable mild cognitive impairment (MCI) and to examine whether self-report, as measured by the CSRQ, is associated with objective measures of hearing, auditory processing, and cognition. Method: Data analyses included 97 older adults of ages 61-91 years. Participants completed the CSRQ selfreport measure as well as a battery of objective measures, including pure-tone audiometry, degraded speech understanding, temporal processing, and memory. Results: Older adults with probable MCI rated their cognitive abilities more poorly than those without MCI (p = .002), but ratings of hearing and auditory abilities did not differ between the two groups (p = .912). Age and CSRQ Hearing subscale ratings explained a significant proportion of variance in objective measures of hearing and degraded speech understanding (R² = .39, p < .001). Age, sex, mental status, and CSRQ Cognition subscale ratings explained a significant proportion of variance in objective memory performance (R² = .55, p < .001). Conclusions: Taken together, these results suggest that the CSRQ is an appropriate self-report measure of hearing, cognition, and some aspects of auditory processing for older adults with and without probable MCI. [ABSTRACT FROM AUTHOR]

Auditory cognitive training (ACT) improves attention in older adults; however, the underlying neurophysiological mechanisms are still unknown. The present study examined the effects of ACT on the P3b event-related potential reflecting attention allocation (amplitude) and speed of processing (latency) during stimulus categorization and the P1-N1-P2 complex reflecting perceptual processing (amplitude and latency). Participants completed an auditory oddball task before and after 10 weeks of ACT (n = 9) or a no contact control period (n = 15). Parietal P3b amplitudes to oddball stimuli decreased at post-test in the trained group as compared to those in the control group, and frontal P3b amplitudes show a similar trend, potentially reflecting more efficient attentional allocation after ACT. No advantages for the ACT group were evident for auditory perceptual processing or speed of processing in this small sample. Our results provide preliminary evidence that ACT may enhance the efficiency of attention allocation, which may account for the positive impact of ACT on the everyday functioning of older adults. [ABSTRACT FROM AUTHOR]