Views and Perceptions of Amyloid Imaging in a Preclinical Alzheimer's Disease Trial.

Background: Many cognitively unimpaired older adults are interested in learning their Alzheimer's disease (AD) biomarker status, but little is known about motivations to undergo biomarker testing and result disclosure in the setting of preclinical AD trials.

Objectives: Examine whether motivations to undergo AD biomarker testing and disclosure differ for individuals who have elevated amyloid compared to those with not elevated amyloid, and whether disclosure of amyloid results impacts participants' motivations.

Design, Setting, Participants: We conducted post-hoc analyses using data from the EARLY study, a preclinical AD trial of the beta-secretase inhibitor atabecestat. As part of the screening process of the trial, participants underwent biomarker testing and disclosure. We analyzed data from n=2241 participants.

Measurements: We analyzed data from the Views and Perceptions of Amyloid Imaging (VPAI), a 9-item questionnaire assessing how strongly participants agreed with motivating factors for undergoing amyloid testing. The VPAI was administered at the first screening visit and again after amyloid disclosure.

Results: Prior to amyloid disclosure, a greater proportion of participants in the elevated amyloid group responded at the two highest levels of endorsement for the items, "to confirm the feeling that I might already be developing symptoms of AD dementia" (p<0.001) and "to prepare my family for my possible illness in the future" (p=0.008), compared to participants in the not elevated amyloid group. Following disclosure, the not elevated amyloid group had higher odds of positive change in categorical VPAI item level scores for the items "to put mind at ease" (OR: 0.54; p<0.001), "to confirm the feeling that I might already be developing symptoms of AD dementia" (OR: 0.79; p=0.049), and "to prepare my family for my possible illness in the future" (OR: 0.67; p=<0.001), while the elevated amyloid group had higher odds of positive change for the item "curiosity" (OR:1.32; p=0.014).

Conclusions: Investigators might consider adjusting recruitment strategies for future trials to align with the motivations to undergo biomarker testing and disclosure most strongly endorsed by participants with elevated amyloid.