- Edwards, Lauren;
- Thomas, Kelsey;
- Weigand, Alexandra;
- Edmonds, Emily;
- Clark, Alexandra;
- Walker, Kayla;
- Brenner, Einat;
- Nation, Daniel;
- Maillard, Pauline;
- Bondi, Mark;
- Bangen, Katherine
BACKGROUND: Alzheimers disease (AD) and cerebrovascular disease are common, co-existing pathologies in older adults. Whether the effects of cerebrovascular disease and AD biomarkers on cognition are additive or synergistic remains unclear. OBJECTIVE: To examine whether white matter hyperintensity (WMH) volume moderates the independent association between each AD biomarker and cognition. METHODS: In 586 older adults without dementia, linear regressions tested the interaction between amyloid-β (Aβ) positron emission tomography (PET) and WMH volume on cognition, independent of tau-PET. We also tested the interaction between tau-PET and WMH volume on cognition, independent of Aβ-PET. RESULTS: Adjusting for tau-PET, the quadratic effect of WMH interacted with Aβ-PET to impact memory. There was no interaction between either the linear or quadratic effect of WMH and Aβ-PET on executive function. There was no interaction between WMH volume and tau-PET on either cognitive measure. CONCLUSION: Results suggest that cerebrovascular lesions act synergistically with Aβ to affect memory, independent of tau, highlighting the importance of incorporating vascular pathology into biomarker assessment of AD.