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This study examined the relationship between total vegetable intake, including specific vegetable types with long-term late-life dementia (LLD) risk in older Australian women. 1206 community-dwelling older women aged ≥70 years were included. Consumption of total vegetable intake and vegetable types (yellow/orange/red [YOR], cruciferous, allium, green leafy vegetables [GLV], and legumes) were estimated using a validated food frequency questionnaire at baseline (1998). LLD was considered any form of dementia occurring after 80 years of age. LLD events (comprising hospitalisation and/or death) were obtained from linked health records. Associations were examined using restricted cubic splines within multivariable-adjusted (including APOE4 genotype) Cox proportional hazard models. Over 14.5 years of follow-up (∼15 134 person-years) there were 207 (17.2%) LLD events, 183 (15.25%) with LLD hospitalisations and 83 (6.9%) with LLD deaths. Compared to women in the lowest Quartile (Q1) of total vegetable intake, those with higher intakes (Q3, but not Q4) had 39% lower hazard for a LLD death. Compared to Q1, women in the highest quartile of YOR intake (Q4) consistently recorded lower hazards for a LLD event (47%), hospitalisation (46%), and death (50%). Similarly, women with the highest allium intake (Q4), had lower hazards for LLD events (36%) and deaths (49%), compared to Q1. Women with the highest GLV intake (Q4) also recorded 45% lower hazards for a LLD death. Whilst total vegetable intake may be important, allium, GLV and especially YOR vegetables may be most beneficial when considering LLD risk. These results require further validation in other cohorts, including men. The clinical trial registry numbers are https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=368778&isReview=true, CAIFOS: ACTRN12615000750583, and https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=372818&showOriginal=true&isReview=true, PLSAW: ACTRN12617000640303.

Background: Impaired muscle function has been identified as a risk factor for declining cognitive function and cardiovascular health, both of which are risk factors for late-life dementia (after 80 years of age). We examined whether hand grip strength and timed-up-and-go (TUG) performance, including their change over 5 years, were associated with late-life dementia events in older women and whether any associations provided independent information to Apolipoprotein E ℇ 4 (APOE ℇ 4) genotype., Methods: Grip strength and TUG were assessed in community-dwelling older women (mean ± SD; age 75.0 ± 2.6 years) at baseline (n = 1225) and 5 years (n = 1052). Incident 14.5-year late-life dementia events (dementia-related hospitalization/death) were obtained from linked health records. Cardiovascular risk factors (Framingham Risk Score), APOE genotyping, prevalent atherosclerotic vascular disease and cardiovascular-related medications were evaluated at baseline. These were included in multivariable-adjusted Cox-proportional hazards models assessing the relationship between muscle function measures and late-life-dementia events., Results: Over follow-up, 207 (16.9%) women had a late-life dementia event. Compared with women with the highest grip strength (Quartile [Q] 4, 25.8 kg), those with the lowest grip strength (Q1, 16.0 kg) had greater hazard for a late-life dementia event (HR 2.27 95% CI 1.54-3.35, P < 0.001). For TUG, the slowest women (Q4, 12.4 vs. Q1, 7.4 s) also recorded a greater hazard for a late-life dementia event (HR 2.10 95% CI 1.42-3.10, P = 002). Weak hand grip (<22 kg) or slow TUG (>10.2 s) provided independent information to the presence of an APOE ℇ 4 allele (n = 280, 22.9%). Compared with women with no weakness and no APOE ℇ 4 allele, those with weakness and APOE ℇ 4 allele had a greater hazard (HR 3.19 95% CI 2.09-4.88, P < 0.001) for a late-life dementia event. Women presenting with slowness and the APOE ℇ 4 allele also recorded a greater hazard for a late-life dementia event (HR 2.59 95% CI 1.64-4.09, P < 0.001). For 5-year muscle function changes, compared with women with the lowest performance decrement (Q1), those with the largest decrement (Q4) had higher hazards for a late-life dementia event (grip strength HR 1.94 95% CI 1.22-3.08, P = 0.006; TUG HR 2.52 95% CI 1.59-3.98, P < 0.001) over the next 9.5 years., Conclusions: Weaker grip strength and slower TUG, and a greater decline over 5 years, were significant risk factors for a late-life-dementia event in community-dwelling older women, independent of lifestyle and genetic risk factors. Incorporating muscle function measures as part of dementia screening appears useful to identify high-risk individuals who might benefit from primary prevention programmes., (© 2023 The Authors. Journal of Cachexia, Sarcopenia and Muscle published by John Wiley & Sons Ltd on behalf of Society on Sarcopenia, Cachexia and Wasting Disorders.)

Objective: To determine the effect of β-amyloid (Aβ) level on progression risk to mild cognitive impairment (MCI) or dementia and longitudinal cognitive change in cognitively normal (CN) older individuals., Methods: All CN from the Australian Imaging Biomarkers and Lifestyle study with Aβ PET and ≥3 years follow-up were included (n = 534; age 72 ± 6 years; 27% Aβ positive; follow-up 5.3 ± 1.7 years). Aβ level was divided using the standardized 0-100 Centiloid scale: <15 CL negative, 15-25 CL uncertain, 26-50 CL moderate, 51-100 CL high, >100 CL very high, noting >25 CL approximates a positive scan. Cox proportional hazards analysis and linear mixed effect models were used to assess risk of progression and cognitive decline., Results: Aβ levels in 63% were negative, 10% uncertain, 10% moderate, 14% high, and 3% very high. Fifty-seven (11%) progressed to MCI or dementia. Compared to negative Aβ, the hazard ratio for progression for moderate Aβ was 3.2 (95% confidence interval [CI] 1.3-7.6; p < 0.05), for high was 7.0 (95% CI 3.7-13.3; p < 0.001), and for very high was 11.4 (95% CI 5.1-25.8; p < 0.001). Decline in cognitive composite score was minimal in the moderate group (-0.02 SD/year, p = 0.05), while the high and very high declined substantially (high -0.08 SD/year, p < 0.001; very high -0.35 SD/year, p < 0.001)., Conclusion: The risk of MCI or dementia over 5 years in older CN is related to Aβ level on PET, 5% if negative vs 25% if positive but ranging from 12% if 26-50 CL to 28% if 51-100 CL and 50% if >100 CL. This information may be useful for dementia risk counseling and aid design of preclinical AD trials., (Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.)

Introduction: For decades, researchers have tried to understand the moderating effect of APOE ε4 carriage on the relationship between physical activity (PA), brain health and dementia risk. However, this field has produced inconsistent findings., Method: We conducted a systematic review of the literature, searching for observational and interventional studies examining the effect of APOE ε4 carriage on the relationships between PA, dementia risk and different markers of brain health., Results: Observational studies using dementia risk as a primary outcome measure generally found that in shorter follow-up periods (up to 10 years) both APOE ε4 carriers and non-carriers benefit from PA, although longer follow-ups showed mixed results. In neuroimaging studies, mainly carriers or both groups showed benefits. Additionally, the association between PA and amyloid burden was more evident among carriers. Overall, studies with greater samples of active APOE ε4 carriers are more likely to report benefits within this group in terms of lower dementia risk and reduced brain pathology., Discussion: Although we have identified some patterns for the modulating effect of APOE ε4 on PA and dementia or brain pathology, the available data is, overall, inconclusive. Heterogeneity in study design, methodology, and outcomes blur the ability to detect clear associations., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objective: To prospectively examine 8-year risk of clinical disease progression to mild cognitive impairment (MCI)/dementia in older adults ≥60 with superior episodic memory (SuperAgers) compared to those cognitively normal for their age (CNFA). Additionally, to determine the extent to which SuperAgers were resilient to the negative effects of elevated amyloid-beta (Aβ+) on cognition., Method: Participants were classified as SuperAgers based on episodic memory performance consistent with younger adults aged 30-44 and no impairment on non-memory tests (n = 179), and were matched with CNFA on age, sex, education, and follow-up time (n = 179). Subdistribution hazard models examined risk of clinical progression to MCI/dementia. Linear mixed models assessed the effect of Aβ on cognition over time., Results: Prevalence of Aβ+ and APOE ε4 was equivalent between SuperAgers and CNFA. SuperAgers had 69%-73% reduced risk of clinical progression to MCI/dementia compared to CNFA (HR: 0.27-0.31, 95% CI: 0.11-0.73, p < .001). Aβ+ was associated with cognitive decline in verbal memory and executive function, regardless of SuperAger/CNFA classification. In the absence of Aβ+, equivalent age-related changes in cognition were observed between SuperAgers and CNFA., Conclusions: SuperAgers displayed resilience against clinical progression to MCI/dementia compared to CNFA despite equivalent risk for Alzheimer's disease (AD); however, SuperAgers had no greater protection from Aβ+ than CNFA. The deleterious effects of Aβ on cognition persist regardless of baseline cognitive ability. Thus, superior cognitive performance does not reflect resistance against the neuropathological processes associated with AD, and the observed resilience for SuperAgers may instead reflect neuropsychological criteria for cognitive impairment., (© The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Preclinical Alzheimer's disease (AD) is defined by cerebral amyloid-β positivity (Aβ+) in cognitively normal (CN) older adults., Objective: To estimate the risk of progression to the symptomatic stages of AD due to PET Aβ+ and the extent that progression was influenced by other demographic, genetic, and clinical characteristics in a large prospective study., Methods: Fine-Gray subdistribution modeling was used to examine the risk of progression from CN to MCI/dementia due to Aβ+, APOEɛ4 carriage, and their interaction in the Australian Imaging, Biomarkers and Lifestyle (AIBL) flagship study of aging CN cohort (n = 599) over 8 years., Results: 17.7% Aβ+ and 8.1% Aβ-progressed over 8 years (OR: 2.43). Risk of progression for Aβ+ was 65-104% greater than Aβ-. Aβ+ APOEɛ4 carriers were at 348% greater risk than all other participants. Significant risk factors of progression in Aβ+ were age (HR: 1.05), PET SUVR (HR: 2.49) and APOE ɛ4 carriage (HR: 2.63); only age was a significant risk factor in Aβ-(HR: 1.09). Aβ-progressors were not near the threshold for Aβ+. These relationships were not moderated by hypertension, diabetes, obesity, or stroke/TIA., Conclusion: Aβ+ is an important prognostic marker for progression from CN to MCI/dementia in older adults and APOEɛ4 carriage provides further predictive value in the presence of Aβ+. These data suggest that Aβ-associated clinical progression is consistent with clinical-pathological models of AD, whereas progression in the absence of elevated Aβ deposition may be the result of neuropathological processes other than AD that accumulate with age.

Mutations in the gene for valosin containing protein (VCP) cause autosomal dominant inclusion body myopathy associated with Paget disease and frontotemporal dementia (IBMPFD). To investigate the role of this novel gene in sporadic forms of frontotemporal dementia (FTD), we genotyped 27 single nucleotide polymorphisms covering the entire VCP genomic region in 198 patients with sporadic FTD and 184 matched controls from Germany. No significant association could be demonstrated. There is no evidence, that common variants in VCP confer a strong risk to the development of sporadic FTD.

The H1 haplotype of the tau gene, MAPT, has been linked to the sporadic tauopathies corticobasal degeneration and progressive supranuclear palsy; however, there have been inconsistent findings regarding association with frontotemporal dementia (FTD). We investigated MAPT haplotype diversity, in 171 sporadic FTD and 186 healthy controls individuals, and report no single marker or haplotype association with increased risk or changes in age at onset. These findings do not support an association of MAPT with FTD but do not rule out its association with other tauopathies.

Mutations of the chromatin modifying protein 2B gene (CHMP2B) were identified, in a Danish pedigree, to cause familial frontotemporal dementia (FTD). To explore the possible genetic contribution of common CHMP2B variants in sporadic FTD, we analyzed 14 single nucleotide polymorphisms covering the entire genomic region of CHMP2B. After adjustment for multiple testing single marker and haplotype analysis revealed no significant association with sporadic FTD. Thus, we conclude that CHMP2B can be excluded as a susceptibility gene conferring risk to sporadic forms of FTD.

Objective: The microtubule-associated protein tau gene (MAPT) contains two extended haplotypes, H1 and H2, which have been linked with sporadic tauopathies. However, there is little evidence as to how these haplotypes may influence the clinical features of the disease. The aim of this study was to investigate the MAPT haplotypes in relation to risk for, and functional alterations of glucose metabolism in, patients with frontotemporal dementia (FTD)., Method: The authors investigated MAPT haplotypes in 142 individuals with FTD and 292 comparison subjects. Additionally, in a subset of 41 individuals with FTD and 16 comparison subjects, the authors undertook functional [ (18)F]fluorodeoxyglucose positron emission tomography (PET) imaging., Results: MAPT haplotype distribution did not differ significantly between individuals with FTD and comparison subjects. However, the H2 haplotype was clinically associated with an earlier age at onset of FTD, which presented in a dose-dependent manner. Correspondingly, PET analysis revealed functional differences in glucose utilization patterns between MAPT haplotypes, with H2 carriers having a more pronounced hypometabolism in frontal brain areas than H1 carriers, which could not be accounted for by differences in duration of illness., Conclusions: While the extended MAPT H1 and H2 haplotypes do not appear to confer risk for disease development, the H2 haplotype appears to modify age at onset and functionally shows a more severe decline of glucose utilization in frontal brain areas.