Worry Moderates Plasma Placental Growth Factor (PIGF) and Cognition in Older Adults with Amnestic Mild Cognitive Impairment (aMCI).

Background: Elevated worry is an early indicator of cognitive decline in older adults. Worry has been linked to pro-inflammatory processes though the exact relations between worry, inflammation, and cognition in older adults with amnestic mild cognitive impairment (aMCI) remain unexplored. The present study studied the association of worry with proteomic biomarkers of inflammation and cognition.

Method: Participants include 66 community-dwelling older adults with amnestic mild cognitive impairment (aMCI). Inflammation was analyzed using the modified aptamer-based assay SomaScan Platform. Primary analyses consisted of two hierarchical regression models with mean-centered worry and inflammation as independent variables and age as covariate. Composite scores of executive function and processing speed were entered as the dependent variable in separate models.

Results: Results indicate a significant interaction between worry and placental growth factor (PIGF) on processing speed, such that worry intensifies the inverse relationship of PIGF and processing speed. Worry did not interact with PIGF to predict executive functioning.

Conclusion: Findings indicate an important moderating role of worry in the association of pro-inflammatory PIGF and processing speed. Results suggest that older adults with cognitive impairment may be more susceptible to the indirect impact of worry and expands emerging research on the role of PIGF in cognitive impairment.