| Autor: |
Langhough, Rebecca E, Du, Lianlian, Cody, Karly Alex, Jonaitis, Erin M., Hermann, Bruce P, Chin, Nathaniel A., Rivera‐Rivera, Leonardo A., Cadman, Robert V., Pompa, Christian C., Hudson, Sarah, Christian, Bradley T., Eisenmenger, Laura B., Betthauser, Tobey J, Johnson, Sterling C |
| Zdroj: |
Alzheimer's & Dementia: The Journal of the Alzheimer's Association; Dec2023 Supplement 24, Vol. 19, p1-3, 3p |
| Abstrakt: |
Background: Amyloid‐PET and white matter hyperintensities (WMH) associations in older adults have variously been interpreted as separate or dependent processes. In this study, we examine evidence for a temporal relationship between amyloid‐PET and WMH and investigate how both contribute to cognitive decline in a baseline cognitively unimpaired (CU) sample. Method: We analyzed longitudinal WMH and PACC3 cognition in n = 240 Wisconsin Registry for Alzheimer's Prevention participants who were CU at cognitive baseline with ≥1 amyloid‐PET and T2‐FLAIR scan. Amyloid burden was assessed using [C‐11]Pittsburgh Compound B (PiB) PET and a multi‐ROI DVR value; DVR>1.19 = PiB+. WMH lesion volume was segmented and summed by the Lesion Segmentation Tool (LST) version 1.2.3 in SPM12 from T1‐weighted and T2‐weighted FLAIR scans; TIV‐adjusted WMH >2.06 = WMH+. Sampled iterative local approximation (SILA) modeling aligned biomarker levels to positivity duration scale (years = 0 at biomarker+ threshold). To investigate how amyloid burden relates to WMH trajectories, time at each WMH scan was operationalized four ways: age, ∼WMH+ duration, years_since_baseline_scan, and ∼PiB+ duration. We compared model fits and interaction effects for the various PiB status*time interactions (mixed effects models; retaining significant quadratic time terms; random slopes and intercepts). We also examined whether PACC3 age‐related trajectories differed by PiB/WMH +/‐ groups (at last scan). Result: More women were WMH+ and APOE4 was more common among PiB+ (see also Table1). Significant interactions using age or years_since_baseline_scan suggested slightly faster WMH accumulation in PiB+ vs PiB‐ at older ages. In parallel models, WMH+ duration*PiB status and PiB+ duration*PiB status did not show differences between PiB+ and PiB‐ WMH trajectories. Time operationalized as WMH+ duration yielded the best fitting model (see Table2 and Fig1A‐D). PACC3 decline was fastest in the PiB+/WMH+ group, followed by PiB+/WMH‐ (Fig1E). PiB+ was more common than WMH+ and tended to precede it when both were present (Table1; Fig1F). Conclusion: In this baseline CU sample, WMH+ was less common and occurred later in life, on average, than PiB+. Associations between amyloid burden and WMH trajectories were driven by older ages, suggesting potential unidentified age‐related mediators in this relationship. Presence of both amyloid and WMH was associated with fastest preclinical cognitive decline. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
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