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Sex and gender—biological and social constructs—significantly impact the prevalence of protective and risk factors, influencing the burden of Alzheimer's disease (AD; amyloid beta and tau) and other pathologies (e.g., cerebrovascular disease) which ultimately shape cognitive trajectories. Understanding the interplay of these factors is central to understanding resilience and resistance mechanisms explaining maintained cognitive function and reduced pathology accumulation in aging and AD. In this narrative review, the ADDRESS! Special Interest Group (Alzheimer's Association) adopted a multidisciplinary approach to provide the foundations and recommendations for future research into sex‐ and gender‐specific drivers of resilience, including a sex/gender‐oriented review of risk factors, genetics, AD and non‐AD pathologies, brain structure and function, and animal research. We urge the field to adopt a sex/gender‐aware approach to resilience to advance our understanding of the intricate interplay of biological and social determinants and consider sex/gender‐specific resilience throughout disease stages. Highlights: Sex differences in resilience to cognitive decline vary by age and cognitive status.Initial evidence supports sex‐specific distinctions in brain pathology.Findings suggest sex differences in the impact of pathology on cognition.There is a sex‐specific change in resilience in the transition to clinical stages.Gender and sex factors warrant study: modifiable, immune, inflammatory, and vascular. [ABSTRACT FROM AUTHOR]

Objectives: Sensory impairment is a hypothesized risk factor for cognitive decline; however, the psychosocial pathways are not well understood. We evaluated whether the association between visual impairment (VI) and cognitive decline was partially mediated via depressive symptoms, loneliness, or social activity. Methods: We used data from 2601 older adults enrolled in the Memory and Aging Project in 1997 and the Minority Aging Research Study in 2004 with neuropsychological tests across five domains measured annually for up to 16 years. VI was assessed with the Rosenbaum Pocket Vision Screener. Depressive symptoms, loneliness, and social activity were self‐reported using validated scales. We used structural equation models to estimate the associations of VI with baseline and change in cognitive function, directly and indirectly through each mediator (depressive symptoms, loneliness, and social activity). We evaluated mediation via "psychological distress" using a latent variable combining depressive symptoms and loneliness. Results: The association between VI and global cognitive decline was mediated via lower social activity (indirect effect) [95% confidence interval (CI)] of linear slope: −0.025 (−0.048, −0.011), via loneliness (−0.011 [95% CI: −0.028, −0.002]), and via psychological distress (−0.017 [95% CI: −0.042, −0.003]). We did not find sufficient evidence for mediation via depressive symptoms alone. Conclusions: The harmful effect of VI on cognitive decline may be partially mediated through loneliness and lower social activity. Key points: We evaluated whether psychosocial factors mediate the association between visual impairment and cognitive decline.With data from the Memory and Aging Project and the Minority Aging Research Study, we used structural equation models to estimate the total, direct, and indirect associations through each mediator (depressive symptoms, loneliness, lower social activity, and a latent variable, psychological distress, combining depressive symptoms and loneliness).We found evidence for partial mediation via social activity and loneliness. [ABSTRACT FROM AUTHOR]

Effects of concreteness and grammatical class on lexical-semantic processing are well-documented, but the role of sensory-perceptual and sensory-motor features of concepts in underlying mechanisms producing these effects is relatively unknown. We hypothesized that processing dissimilarities in accuracy and response time performance in nouns versus verbs, concrete versus abstract words, and their interaction can be explained by differences in semantic weight--the combined amount of sensory-perceptual and sensory-motor information to conceptual representations--across those grammatical and semantic categories. We assessed performance on concrete and abstract subcategories of nouns and verbs with a semantic similarity judgment task. Results showed that when main effects of concreteness and grammatical class were analyzed in more detail, the grammatical-class effect, in which nouns are processed more accurately and quicker than verbs, was only present for concrete words, not for their abstract counterparts. Moreover, the concreteness effect, measured at different levels of abstract words, was present for both nouns and verbs, but it was less pronounced for verbs. The results do not support the grammatical-class hypothesis, in which nouns and verbs are separately organized, and instead provide evidence in favor of a unitary semantic space, in which lexical-semantic processing is influenced by the beneficial effect of sensory-perceptual and sensory-motor information of concepts.

INTRODUCTION: We compared gender disparities in later‐life memory, overall and by education, in India and the United States (US). METHODS: Data (N = 7443) were from harmonized cognitive assessment protocols (HCAPs) in the Longitudinal Aging Study of India‐Diagnostic Assessment of Dementia (LASI‐DAD; N = 4096; 2017‐19) and US Health and Retirement Study HCAP (HRS‐HCAP; N = 3347; 2016‐17). We derived harmonized memory factors from each study using confirmatory factor analysis. We used multivariable‐adjusted linear regression to compare gender disparities in memory function between countries, overall and by education. RESULTS: In the United States, older women had better memory than older men (0.28 SD‐unit difference; 95% CI: 0.22, 0.35). In India, older women had worse memory than older men (−0.15 SD‐unit difference; 95% CI: −0.20, −0.10), which attenuated with increasing education and literacy. CONCLUSION: We observed gender disparities in memory in India that were not present in the United States, and which dissipated with education and literacy. [ABSTRACT FROM AUTHOR]

Objective: To compare longitudinal verbal fluency performance among Latinx Spanish speakers who develop Alzheimer's disease to those who do not develop dementia in absolute number of words produced on each task and their ratio to combine both scores. Method: Participants included 833 Latinx Spanish-speaking older adults from a community-based prospective cohort in Manhattan. We performed growth curve modeling to investigate the trajectories of letter and semantic fluency, and their ratio (i.e., 'semantic index'), between individuals who developed Alzheimer's disease and those who did not (i.e., controls). The semantic index quantifies the proportion of words generated for semantic fluency in relation to the total verbal fluency performance. Results: Letter fluency performance did not decline in controls; we observed a linear decline in those who developed Alzheimer's disease. Semantic fluency declined in both groups and showed an increased rate of change over time in the incident Alzheimer's disease group; in comparison, the control group had a linear and slower decline. There were no group differences in the longitudinal trajectory (intercept and slope) of the semantic index. Conclusion: A decline in letter fluency and a more rapid and accelerating decline over time in semantic fluency distinguished people who developed Alzheimer's disease from controls. Using the semantic index was not a superior marker of incident Alzheimer's disease compared to examining the two fluency scores individually. Results suggest the differential decline in verbal fluency tasks, when evaluated appropriately, may be useful for early identification of Alzheimer's disease in Latinx Spanish speakers, a historically understudied population. [ABSTRACT FROM AUTHOR]

Primary aims of this systematic review were to: (1) identify the range of subjective memory measures used in the stroke and stroke-related aphasia literature and (2) critically appraise their psychometric properties as well as (3) the methodological qualities of studies that included them, (4) investigate whether such measures provide an accurate reflection of memory impairments (i.e., in comparison to norms from age-matched, neurotypical participants), (5) document the representation of individuals with stroke-related aphasia, and (6) examine the extent to which subjective memory measures correlate with objective memory measures. Systematic review of the literature from 1970 to June 2019 using a comprehensive range of relevant search terms in EMBASE, Medline, PsychINFO, SCOPUS, and Web of Science. Eligibility criteria were for studies to include adults who had suffered of clinical stroke, to report a subjective memory measure that was completed by the stroke survivors, to be reported in a peer-reviewed journal, and to be published in English or Dutch. Quality appraisal was carried out for the included studies as well as the subjective memory measures they employed. A total of 7,077 titles or abstracts were screened, with 41 studies included in the quantitative and qualitative synthesis. Twenty-six subjective memory measures were used in the included studies. The critical appraisal of their psychometric properties and the methodological quality of the included studies revealed significant shortcomings; for example, neurotypical participants were included in only 14 of the 41 studies. When statistical comparisons were made, different outcomes arose. Only eight studies statistically compared subjective with objective memory measures. This literature domain currently provides an unclear picture as to how memory limitations affect participation in stroke and stroke-related aphasia. A broad range of subjective memory measures have been used to determine stroke survivors' perceptions of their everyday memory issues. Because of psychometric weaknesses such as inadequate reliability and cross-cultural validity among subjective memory measures, there remains a need to carefully review a given measure's properties to determine if it is appropriate for use with a given stroke survivor. Stroke survivors with aphasia have been infrequently included or inadequately described in studies of subjective memory measures, and thus how these individuals perceive their everyday memory abilities requires further investigation. Although the relationship between subjective and objective memory measures has been infrequently investigated by stroke researchers, both types of measures should be considered as they likely offer complementary rather than redundant information about stroke survivors' memory abilities. [ABSTRACT FROM AUTHOR]