Table 1.
Sample characteristics.
Table 2.
Regression analyses for the relationships of MIC-1/GDF15 level with brain GM volume at both wave 1 and 2.
Fig 1.
Vertex-based analyses of associations between Macrophage Inhibitory Cytokine—1 (MIC-1/GDF15) serum levels and cortical volume at Wave 1.
The result was adjusted for age, sex, years of education, scanner, and intracranial volume (ICV) (Model 1). The results were corrected at a false discovery rate (FDR) of 0.05 and projected onto a semi-inflated brain. Negative correlations are indicated by cyan and blue, and positive correlations by red and yellow.
Fig 2.
Vertex-wise analyses of the relationships between MIC-1/GDF15 serum levels and subcortical structures at Wave 1.
The result was after FDR correction and adjusted for age, sex, years of education, scanner, and intracranial volume (ICV) (Model 1). Regions showing statistical significance were negatively correlated with MIC-1/GDF15 serum levels. Left pallidum and bilateral thalami survived FDR correction. After FDR correction, the ranges of statistical significance (p values) were changed to 0–0.043 for left pallidum, 0–0.038 for left thalamus, and 0–0.039 for right thalamus.
Table 3.
Regression analyses for the relationships of MIC-1/GDF15 at wave 1 with the changes in brain GM volume over two years.
Table 4.
Regression analyses for the associations between Wave 1 GM volumes and changes in MIC-1/GDF15 serum levels.
Table 5.
Regression analyses for the relationships of MIC-1/GDF15 changes with brain GM volume changes over two years.
Fig 3.
Associations of MIC-1/GDF15 level changes and cortical volume changes over two years.
The result was adjusted for age, sex, years of education, scanner, and ICV (Model 1). Negative correlations are indicated by cyan and blue, and positive correlations by red and yellow. The results were after correction for multiple comparisons using FDR. Volume changes of parts of superior temporal, middle temporal and superior frontal regions negatively correlated with MIC-1/GDF15 level change over two years.
Fig 4.
The moderation analysis model.
A graphical illustration of the moderation analysis of whether the initial MIC-1/GDF15 serum levels at Wave 1 moderated the strength of the associations between changes in MIC-1/GDF15 serum levels and GM volumes.
Table 6.
Sobel tests for the mediation effects of the GM measures on the statistically significant relationships between MIC-1/GDF15 and GCS at Wave 1 and 2.