Novel, standardized sample collection from the brain-nose interface.

Background: Diagnostics for neurodegenerative diseases lack non-invasive approaches suitable for early-stage biochemical screening and routine examination of neuropathology. Biomarkers of neurodegenerative diseases pass through the brain-nose interface (BNI) and accumulate in nasal secretion. Sample collection from the brain-nose interface presents a compelling prospect as basis for a non-invasive molecular diagnosis of neuropathologies.

Basic Science and Pathogenesis.

Background: The Apolipoprotein E ε4 (APOE-ε4) allele is common in the population, but acts as the strongest genetic risk factor for late-onset Alzheimer's disease (AD). Despite the strength of the association, there is notable heterogeneity in the population including a strong modifying effect of genetic ancestry, with the APOE-ε4 allele showing a stronger association among individuals of European ancestry (EUR) compared to individuals of African ancestry (AFR). Given this heterogeneity, we sought to identify genetic modifiers of APOE-ε4 related to cognitive decline leveraging APOE-ε4 stratified and interaction genome-wide association analyses (GWAS).

Basic Science and Pathogenesis.

Background: "SuperAgers" are older adults (ages 80+) whose cognitive performance resembles that of adults in their 50s to mid-60s. Factors underlying their exemplary aging are underexplored in large, racially diverse cohorts. Using eight cohorts, we investigated the frequency of APOE genotypes in SuperAgers compared to middle-aged and older adults.

Clinical Manifestations.

Background: Prior longitudinal studies among older adults have documented associations between hearing loss and changes in brain morphology. Whether interventions involving hearing aids can reduce age-related atrophy is unknown. A substudy within the Aging and Cognitive Health Evaluation in Elders (ACHIEVE, Clinicaltrials.

Clinical Manifestations.

Background: Higher level of cognitive reserve (CR), measured using proxies such as years of education or literacy, is associated with reduced risk of Mild Cognitive Impairment (MCI) and dementia. Little is known about how CR and other lifestyle factors impact non-cognitive outcomes, including depression and other neuropsychiatric symptoms (e.g.