Longitudinal and concurrent C-reactive protein and diet associations with cognitive function in the population-based...

Area of Science:

• Neuroscience
• Immunology
• Gerontology

Background:

• Immune dysregulation is linked to Alzheimer's disease (AD), but mechanisms and timing remain unclear.
• Investigating inflammatory markers and dietary patterns is crucial for understanding AD pathogenesis.

Purpose of the Study:

• To examine associations between serum C-reactive protein (CRP) and Dietary Inflammatory Index (DII) with cognitive decline in AD.
• To determine if CRP mediates the relationship between diet and cognitive function over time.

Main Methods:

• Analysis of 7613 participants from Tromsø6 and Tromsø7 cohorts (2007-2016).
• Cross-sectional and longitudinal analyses using linear regression and linear mixed models.
• Mediation analysis to assess the role of CRP in diet-cognition associations.

Main Results:

• Both CRP and DII were inversely associated with cognitive function (psychomotor speed, executive function) cross-sectionally.
• No prospective association between baseline CRP and cognitive function after 7 years.
• Increased CRP levels correlated with decreased cognitive function (psychomotor speed, executive function, verbal memory) over 7 years.

Conclusions:

• CRP increases likely reflect inflammatory environment changes occurring alongside cognitive decline in AD.
• CRP may serve as a marker for ongoing inflammatory processes impacting cognition, rather than a direct predictor of future decline based on baseline levels.