Search

Objective Cerebrospinal fluid (CSF) and plasma neurofilament light (NFL) concentrations were assessed in relation to longitudinal objective and subjective cognitive outcomes in older adults ranging from normal cognition to mild cognitive impairment. Interactive effects were assessed for apolipoprotein E ϵ4 (APOE4) carriership, a strong genetic risk factor for Alzheimer’s disease and molecular moderator of vascular disease. Method Vanderbilt Memory & Aging Project participants (CSF n = 149, 72 ± 6 years; plasma n = 333, 73 ± 7 years) underwent fasting blood draw and lumbar puncture at baseline for NFL quantification. Serial neuropsychological assessments and subjective cognitive decline (SCD) questionnaires were completed at 18-month increments. Linear mixed effects regression models adjusted for age, sex, race/ethnicity, education, APOE4 carriership (for main effect models), and depressed mood. NFL x APOE4 interaction terms were used as predictors in follow-up models. Results CSF NFL predicted steeper declines in an executive functioning composite score (β = −0.0001, p = 0.001) and WAIS-IV Coding (β = −0.001, p = 0.001). An APOE4 interaction was present for executive functioning (β = −0.0002, p = 0.005) such that CSF NFL associations with longitudinal decline were stronger among APOE4+ participants. Plasma NFL predicted worsening SCD (β = 0.27, p = 0.002) and objective cognitive decline across all domains (p-values Conclusions Both CSF and plasma NFL detect neuropathology associated with cognitive decline among non-demented older adults, especially among APOE4 carriers. Findings further support the value of SCD as reflecting neurodegenerative changes associated with accelerated cognitive aging.

Objective Neurogranin is a postsynaptic protein associated with declining memory and executive functioning in Alzheimer’s disease (ad). While previous research suggests neurogranin concentrations in ad are higher in women, it is unclear whether sex differences exist in earlier disease stages or predict different cognitive outcomes. This study investigates cerebrospinal fluid (CSF) neurogranin in relation to longitudinal cognitive decline in older adults ranging from normal cognition to mild cognitive impairment, assessing for interactions by sex. Method Vanderbilt Memory & Aging Project participants completed baseline fasting lumbar puncture (n = 155, 73 ± 8 years) for neurogranin quantification and serial neuropsychological assessments at 18-month intervals. Linear mixed effect regression adjusting for age, sex (for main effect models), race/ethnicity, education, cognitive diagnosis, depressed mood, and APOE-ε4 carrier status. Results CSF neurogranin predicted worse cognitive decline across multiple domains (p-values Conclusion Results suggest that among nondemented older adults, CSF neurogranin predicts worse longitudinal cognitive decline in women but not in men. Further research is needed to elucidate underlying mechanisms that may account for these differences, such as possible sex hormone factors. These findings highlight the importance of pursuing individualized prevention and treatment approaches to combat accelerated cognitive aging that take into account the possibility of multiple, divergent disease pathways preceding ad and dementia among various demographic groups.