Parfitt, Francine

ImportanceIncreased white matter hyperintensity (WMH) volume is a common magnetic resonance imaging (MRI) finding in both autosomal dominant Alzheimer disease (ADAD) and late-onset Alzheimer disease (LOAD), but it remains unclear whether increased WMH along the AD continuum is reflective of AD-intrinsic processes or secondary to elevated systemic vascular risk factors.ObjectiveTo estimate the associations of neurodegeneration and parenchymal and vessel amyloidosis with WMH accumulation and investigate whether systemic vascular risk is associated with WMH beyond these AD-intrinsic processes.Design, Setting, and ParticipantsThis cohort study used data from 3 longitudinal cohort studies conducted in tertiary and community-based medical centers—the Dominantly Inherited Alzheimer Network (DIAN; February 2010 to March 2020), the Alzheimer’s Disease Neuroimaging Initiative (ADNI; July 2007 to September 2021), and the Harvard Aging Brain Study (HABS; September 2010 to December 2019).Main Outcome and MeasuresThe main outcomes were the independent associations of neurodegeneration (decreases in gray matter volume), parenchymal amyloidosis (assessed by amyloid positron emission tomography), and vessel amyloidosis (evidenced by cerebral microbleeds [CMBs]) with cross-sectional and longitudinal WMH.ResultsData from 3960 MRI sessions among 1141 participants were included: 252 pathogenic variant carriers from DIAN (mean [SD] age, 38.4 [11.2] years; 137 [54%] female), 571 older adults from ADNI (mean [SD] age, 72.8 [7.3] years; 274 [48%] female), and 318 older adults from HABS (mean [SD] age, 72.4 [7.6] years; 194 [61%] female). Longitudinal increases in WMH volume were greater in individuals with CMBs compared with those without (DIAN: t = 3.2 [P = .001]; ADNI: t = 2.7 [P = .008]), associated with longitudinal decreases in gray matter volume (DIAN: t = −3.1 [P = .002]; ADNI: t = −5.6 [P < .001]; HABS: t = −2.2 [P = .03]), greater in older individuals (DIAN: t = 6.8 [P < .001]; ADNI: t = 9.1 [P < .001]; HABS: t = 5.4 [P < .001]), and not associated with systemic vascular risk (DIAN: t = 0.7 [P = .40]; ADNI: t = 0.6 [P = .50]; HABS: t = 1.8 [P = .06]) in individuals with ADAD and LOAD after accounting for age, gray matter volume, CMB presence, and amyloid burden. In older adults without CMBs at baseline, greater WMH volume was associated with CMB development during longitudinal follow-up (Cox proportional hazards regression model hazard ratio, 2.63; 95% CI, 1.72-4.03; P < .001).Conclusions and RelevanceThe findings suggest that increased WMH volume in AD is associated with neurodegeneration and parenchymal and vessel amyloidosis but not with elevated systemic vascular risk. Additionally, increased WMH volume may represent an early sign of vessel amyloidosis preceding the emergence of CMBs.

A dementia friendly community allows people with dementia and their care partners to remain engaged in their community well into the disease. This study presents the results of primary research aimed at exploring perceptions regarding building a dementia friendly community in an African American neighborhood in northeast Florida. Twelve focus groups and five interviews were conducted with people living with dementia, informal and formal care partners, community stakeholders and neighborhood residents, and analyzed using a grounded theory approach. Three main themes emerged from the analyses, including (1) perceived needs, (2) facilitators and barriers to being dementia friendly, and (3) opportunities for the community to become more dementia friendly. Study findings highlight the unique needs of a single African American neighborhood and the importance of culturally tailoring the dementia friendly model to diverse communities.

AbstractBackgroundAfrican Americans are at greater risk of Alzheimer’s disease (AD) and AD‐related dementia (ADRD). They are also less likely to access dementia resources or participate in dementia research. The National Alzheimer’s Project Act (NAPA) calls for special attention to dementia‐related health disparities in high risk groups. Identifying effective tools to improve rates of dementia resource utilization and research participation by African Americans is essential to achieving dementia health equity.MethodTwo neighborhoods of Jacksonville, FL, defined by zip codes, were the focus of this study. Both zip codes have a large population of African American residents per 2010 US Census, and a history of hosting outreach activities by our Alzheimer’s Disease Research Center (ADRC). In one neighborhood, we modified the NAPA Dementia Friendly (DF) America toolkit to serve as a model of outreach. The second neighborhood served as a control (CON), in which we maintained our traditional outreach model of community‐based lectures. Primary outcome measures were: (1) enrollment in ADRC center‐related studies and (2) phone call volumes from individuals seeking dementia resource information. The outcomes in the DF and CON neighborhoods were compared via Fisher’s exact test to those in other zip codes in Jacksonville (OT).ResultIn the 18 months following implementation of the DF intervention, 54 African Americans enrolled in ADRC‐related research (19 DF, 3 CON, 32 OT), compared to 21 during the 18 months prior (2 DF, 0 CON, and 19 OT). The increase in DF residents enrolling in research following the intervention was statistically significant (p =0 .02) relative to OT residents. The increase observed in the CON residents was not statistically significant (p=1.0) compared to OT residents. Call volumes from African Americans increased from 13 prior to program implementation (all from OT) to 62 calls after implementation (22 DF, 1 CON, 39 OT). The increase among DF residents seeking information following the intervention was statistically significant (p =0.008) whereas the increase was not significant in the CON residents (p=0.54).ConclusionResults suggest that the NAPA DFA can be leveraged to improve dementia resource utilization and research participation among community‐dwelling African Americans.

AbstractBackgroundAfrican Americans are at higher risk of developing Alzheimer’s disease (AD) and AD‐related dementia. They are also more likely to live in communities with fewer dementia resources. The 2011 National Alzheimer’s Project Act calls for special attention to dementia‐related health disparities in high risk groups. Ensuring access to dementia‐specific information is one tactic for addressing disparities; however, the method by which information is delivered may play a role in how effectively that information is understood and retained over time.MethodWe delivered the same dementia education presentation to two comparable, predominantly African American neighborhoods in Jacksonville, FL. In one (intervention) community, the presentation was followed by an hour‐long focus group on what makes a community “dementia friendly”, using modified materials from the Dementia Friendly America (DFA) toolbox. In the other (control) community, the presentation was followed by a social hour allowing participants to interact with presenters and ask questions informally. Our primary objective was to assess the impact of the different conditions on AD knowledge.ResultsA 7‐item scale assessing AD knowledge was administered to immediately before and after the educational presentation (pre‐test, immediate post), and again two months later (Intervention group n=40; Control n=37). Additional, one‐year follow‐up was completed on the intervention community (n=21). Groups did not differ in AD knowledge at pre‐test (M=4.5 vs. 4.2, p=NS). At immediate post‐test, both groups improved their scores, but there was again no difference between groups (M=5.8 vs. 5.4, p=NS). At two‐month post‐testing, both groups declined in their knowledge score, but the control group declined more precipitously, yielding a significant group mean difference (M= 5.4 vs. 4.7, p=0.02). At one year follow‐up, a subsample of the intervention group (n=21) was re‐examined and demonstrated no significant decline in knowledge scores as compared to 2‐month follow‐up (M=5.7 vs. 5.4, p=0.36).ConclusionResults suggest that focus group discussion following dementia education as per the DFA model may contribute to greater retention of information and exert a sustainable impact on AD knowledge over time in an African American community setting.

Abstract A number of efforts are underway to better understand the role of genetic variation in successful aging and longevity. However, to date, only two genes have been consistently associated with longevity in humans: APOE and FOXO3, with the APOE ɛ2 allele also protective against dementia. Recently, using an exome-wide SNP array approach, a missense variant CLEC3B c.316G>A (rs13963 p.S106G) was reported to associate with longevity in two independent cohorts of Japanese and Chinese participants. Interestingly, CLEC3B p.S106G is more frequent in Caucasian populations. Herein, we examined the frequency of CLEC3B p.S106G in a Caucasian series of 1,483 neurologically healthy individuals with a specific subset >80 years of age. Although our findings do not support an association between CLEC3B p.S106G and aging without neurological disease (p = .89), we confirmed the association between the APOE ε2 allele and better survival without neurological disease (p = .001). Further assessment of healthy aged cohorts that retain intact neurological function will be critical to understand the etiology of neurodegenerative disease and the role of age at risk.

Introduction: Racial and ethnic groups are under-represented among research subjects who assent to brain donation in Alzheimer disease research studies. There has been little research on this important topic. Although there are some studies that have investigated the barriers to brain donation among African American study volunteers, there is no known research on the factors that influence whether or not Asians or Latinos are willing to donate their brains for research. Methods: African American, Caucasian, Asian, and Latino research volunteers were surveyed at 15 Alzheimer Disease Centers to identify predictors of willingness to assent to brain donation. Results: Positive predictors included older age, Latino ethnicity, understanding of how the brain is used by researchers, and understanding of what participants need to do to ensure that their brain will be donated. Negative predictors included African/African American race, belief that the body should remain whole at burial, and concern that researchers might not be respectful of the body during autopsy. Discussion: The predictive factors identified in this study may be useful for researchers seeking to increase participation of diverse ethnic groups in brain donation.