Association between regional amyloid and regional tau in younger, non-demented individuals in the framingham heart study

biomarker measures overlaid. A. Degree centrality and pDMN variation were negatively correlated, with voxels of high degree centrality typically showing pDMN variation associated with decreased connectivity (R0.389, p < 2310). There appeared to be an interaction between the two connectivity measures and amyloid ICs core, with voxels with low IC scores typically having low degree centrality and high values on pDMN variation, whereas those with high IC scores had high degree centrality and more variable pDMN variation. B. In contrast, voxels with low degree centrality and high values on pDMN variation had high tau IC scores, whereas thosewith low IC scores had lower pDMN variation values and variable degree centrality. Figure 4. Interaction between connectivity measures and association with biomarker measures. A. An interaction termwas added to themodels described in Figure 2. The model predicting amyloid preformed significantly better with the interaction term (R0.249, p < 2310, ANOVA comparing models: F 970.58, p < 2310). Scatterplots were created using visreg in R in order to visualize the interaction between connectivity measures. In order to assess the effect of changes in pDMN variation values on the relationship between degree centrality and amyloid (left), the data were split into tertiles based on pDMN variation, and within each third pDMN variation was controlled for by setting it to the median value for that third. As is evident from the scatterplots, there was a positive correlation between degree centrality and amyloid IC scorewithin all tertiles, increasing from the bottom third of pDMN variation (red) to the top third (green). A similar analysis was done for pDMN variation (right), this time controlling for degree centrality, showing a similar positive correlation between pDMN variation and amyloid IC, again increasing with increasing degree centrality. B. The model predicting tau also preformed significantly better with the interaction term (R0.363, p< 2310, ANOVA comparingmodels: F 2263.2, p < 2310). However, the interaction between connectivity measures were not congruent. There was a positive correlation between degree centrality and tau IC scores in the lower third of pDMN variation values, little correlation in the middle third and a negative correlation in the upper third (left). pDMN variation was positively correlated with tau scores in all three degree centrality tertiles, although the correlation was highest in the bottom third (right). Poster Presentations: Sunday, July 22, 2018 P482