Schedule of Events | Symposia

Title: Exploring Cognitive and Olfactory Differences in APOE e4 Carriers

Poster Session A - Saturday, March 29, 2025, 3:00 – 5:00 pm EDT, Back Bay Ballroom/Republic Ballroom

Hector Reyes¹ (hreyes0762@sdsu.edu), Claire Murphy^1,2,3; ¹San Diego State University, ²SDSU/UCSD Joint Doctoral Program in Clinical Psychology, ³University of California San Diego Department of Psychiatry

Objective: APOE e4 carriers are at heightened risk for Alzheimer’s Disease (AD), exhibiting cognitive and olfactory deficits associated with AD pathology (Corder et al., 1993; Michaelson, 2014; Murphy, 2019; Saunders et al., 1993; Small et al., 2003). This study investigates whether APOE e4 carriers perform differently on cognitive and olfactory tests compared to non-carriers and explores potential moderating effects of tau and amyloid biomarkers. Participants and Methods: Sixty-five cognitively unimpaired adults completed the Alzheimer’s Disease Assessment Scale Cognitive Subscale (ADAS-Cog) and olfactory assessments. All variables were converted to z-scores for comparability. Separate ANOVAs tested group differences for cognitive and olfactory assessments, while linear regressions examined biomarker moderation effects. Results: Results revealed significant group differences between e4 carriers and non-carriers in ratings of odor familiarity (p = .0031. Plasma biomarkers did not significantly moderate the relationship between APOE status and odor familiarity. However, exploratory plots revealed important trends. Familiarity ratings decreased as pTau 181 increased across groups, while AB42/AB40 ratio showed opposing trends for carriers and non-carriers. Conclusions: These findings reveal complex relationships between olfactory performance, APOE status, and AD biomarkers. The results may reflect underlying mechanisms not yet fully understood. Further investigation is needed to clarify the implications of these findings and the role of odor familiarity as a marker of olfactory performance in AD risk. Supported by NIH grant # R01AG062006 from the National Institute on Aging to CM. We thank Conner Frank, Abbey Albertazzi, Taline Bicakci, Aaron Jacobson and Drs. Jaime Mondragon and Douglas Galasko for their contributions.

Topic Area: EXECUTIVE PROCESSES: Development &aging