BASELINE INTERLEUKIN-6 AND LONGITUDINAL PROCESSING SPEED CHANGE IN THE ELDERLY

Inflammation is suspected to play a role in neurodegeneration and is associated with worse memory and smaller medial temporal volumes in controls. Many of the studies, however, have been cross-sectional and little is known about longitudinal changes in cognition due to inflammation. Our objective was to determine if baseline levels of inflammation predicted a steeper slope of cognitive decline longitudinally. Participants were cognitively normal, community dwelling, older adults (mean age = 73.28) followed over multiple visits spanning 4 to 6 years. Participants underwent a fasting blood draw and had their plasma analyzed for interleukin-6 (IL-6) using the Mesoscale platform. At each timepoint, participants completed a series of computerized reaction time tests that yielded a single composite processing speed score. The IL-6 values were log transformed and slope values of the processing speed scores were calculated using linear mixed models. 199 participants were included in this analysis. Higher baseline IL-6 levels predicted greater increases in processing speed slope (p