Author(s)
Yoni Sacknovitz
Scott Widemon
Eli Stein
Eleanor Simonsick
Caterina Rosano
Jonathan B. Overdevest
Affiliation(s)
Columbia University Vagelos College of Physicians and Surgeons;
Abstract:
Educational Objective: At the conclusion of this presentation, the participants should be able to recognize the prevalence of combined sensory impairment and its potential as an early biomarker for cognitive decline.
Objectives: To evaluate synergism in hearing and olfaction sensory impairments related to neuroimaging patterns in older adults.
Study Design: This study is a longitudinal analysis using data sourced from the Health ABC study.
Methods: Olfaction was assessed using the Brief Smell Identification Test (B-SIT) at year 3 of the Health ABC study and hearing was assessed using pure tone audiometry at year 5. MRI was acquired between years 10-12 on a 3T Siemens MRI machine (T1 and DWI sequences were acquired). Participants were categorized into hearing impairment (HI), olfactory impairment (OI), both impairments (HI+OI), or no impairment (NI).
Results: Compared to NI, individuals with combined impairment (HI+OI group) demonstrated significantly higher mean diffusivity (MD) within the left primary auditory cortex, Heschl's gyrus, amygdala, orbitofrontal cortex, perirhinal cortex and right amygdala, orbitofrontal cortex, perirhinal cortex [adjusted beta values (p-value): 1.11 (0.005), 0.93 (0.05), 0.98 (0.03), 0.52 (0.03), 1.21 (0.02), 1.24 (0.02), 0.54 (0.05), 1.20 (0.03); respectively]. Individuals from the selective HI group demonstrated significantly higher MD within the left primary auditory cortex [adjusted beta value (p value): 0.55 (0.05)], whereas selective OI exhibited no significant difference in MD.
Conclusions: Elderly individuals with both olfactory and hearing impairments exhibited significantly higher and broader anatomic patterns of MD within brain areas previously linked to cognitive impairment on MR imaging. Future research should examine the synergistic relationship between sensory deficits and their association with cognitive decline while investigating the reliability of these neuroimaging biomarkers in predicting those at risk for further cognitive decline.