# Association between inflammatory biomarkers and the cognitive response to a multidomain intervention: secondary longitudinal analyses from the MAPT study

## TL;DR

This study found that higher levels of certain inflammatory biomarkers are linked to worse cognitive outcomes in older adults receiving a multidomain intervention for Alzheimer's prevention.

## Contribution

The study identifies specific inflammatory biomarkers associated with cognitive response to a multidomain Alzheimer's intervention.

## Key findings

- Higher GDF15 and TNFR1 levels were linked to worse cognitive function over two years.
- Higher IL6 and CRP levels reduced the likelihood of being a 'good responder' to the intervention.
- Inflammation levels predicted cognitive outcomes in participants receiving the multidomain intervention.

## Abstract

The aim of this study is to evaluate the association of systemic inflammation measured by plasma biomarkers with the change in cognitive function among participants from the Multidomain Alzheimer Preventive Trial (MAPT) exposed to the multidomain intervention (MI). Secondary analysis of the MAPT longitudinal data. MAPT is a randomized, placebo-controlled trial with 3 interventional groups (omega-3 only, MI only, omega-3 plus MI) and a control group. We tested the association of the change in cognitive function with inflammatory biomarkers (tumoral necrosis factor receptor-1 (TNFR1), monocyte chemoattractant protein-1 (MCP1), Growth Differentiation Factor-15 (GDF15), Interleukin-6 (IL6) and C reactive protein (CRP)) using mixed-effects models. A subgroup analysis was performed in those exposed to the MI. The response to the MI was defined as the change in the composite cognitive score over the 2-year clinical follow-up period. by modeling the response to the intervention and identifying “good responders”, i.e., those in the 5th quintile of response at the end of the intervention period (2 years after the measurement of inflammatory markers). We included 1,527 participants (mean age 75.3, SD = 4.4; 64% female). Higher levels of GDF15 and TNFR1 were associated with a worse trajectory in the cognitive composite score in adjusted models. "Good responders" had an estimated mean change in the composite score of 0.051 (SD 0.062) over two years of intervention, compared to -0.136 (SD = 0.111) for the "not-good responders". Higher IL6 levels were associated with a decreased likelihood of being a "good responder" (OR = 0.22, p = 0.018, 95% CI 0.06; 0.78), with similar results for CRP (OR = 0.48, p = 0.009, 95% CI 0.28; 0.84). Higher inflammation was associated with a worse cognitive trajectory among nondemented participants and a lower likelihood of being classified as a "good responder" in those receiving a MI. Further confirmation of these findings could lead to the use of systemic inflammation as inclusion or stratification criteria in prevention trials.

The online version contains supplementary material available at 10.1007/s11357-024-01497-2.