Table 1.

An overview of studies investigating the impact of disclosure of APOE and Amyloid PET test results to research participants

Publication	Project/study name	Type of study	Disclosure of	Main finding(s)
Green et al. 2009 [54]	The Risk Evaluation and Education for Alzheimer’s Disease (REVEAL) Study	RCT	APOE	No differences between the two groups (disclosure vs no disclosure) in changes in time-averaged measures of anxiety, depression, or test-related distress (measured at 6 weeks, 6 months, and 1 year). The ε4-negative subgroup had a significantly lower level of test-related distress than did the ε4-positive one.
Chao et al. 2008 [55]	REVEAL	RCT	APOE	Participants who learned they were ε4 positive were significantly more likely than ε4 negative participants to report AD-specific health behavioral change 1 year after disclosure.
Bemelmans et al. 2016 [31]	N/A	Systematic review	APOE	In cognitively unimpaired research participants with a first-degree relative with AD, disclosure of APOE-ε4 positivity does not lead to elevated anxiety and depression levels. It does increase test-related distress. It results in behavioral changes concerning insurance and health.
Langlois et al. 2019 [56]	Alzheimer’s Prevention Initiative Generation Program	RCT	APOE	Standard protocol for disclosure is reported. Analyses have not been published yet.
Harkins et al. 2015 [57]	Anti-Amyloid Treatment in Asymptomatic Alzheimer’s Disease (A4) Study.	Modified Delphi study to develop consensus on best practices	Amyloid PET	Standard protocol for disclosure is reported.
Burns et al. 2017 [58]	University of Kansas Alzheimer’s Prevention through Exercise [APEX]	RCT	Amyloid PET	Depressive symptoms were stable throughout the visits and not different between groups (elevated vs non-elevated amyloid). Anxiety symptoms peaked at a low level on the day of disclosure in the “elevated” group but were not sustained at 6 weeks or 6 months. Individuals with elevated amyloid had slightly higher total levels of test-related distress compared with the non-elevated amyloid group at 6 weeks and 6 months post-disclosure.
Largent et al. 2020 [32]	Study of Knowledge and Reactions to Amyloid Testing (SOKRATES) recruiting participants from the A4 and Longitudinal Evaluation of Amyloid Risk and Neurodegeneration (LEARN) trials	Observational study	Amyloid PET	Participants generally understood that an “elevated” amyloid PET scan result means increased but presently unquantifiable risk of developing AD dementia. Participants who received an “elevated” result often wanted more information regarding the result. An “elevated” result sparked negative emotions that decreased but did not entirely dissipate with time, but did not lead to extreme distress. Support the safety of disclosing amyloid imaging results to cognitively unimpaired persons following pre-test assessments of knowledge and psychological well-being. Participants who received an “elevated” result reported contemplating and making changes to health behaviors and future plans to a greater extent. Participants with elevated brain amyloid viewed the amyloid PET scan result as a serious, sensitive piece of health information. Irrespective of their brain amyloid status, participants were mindful that their amyloid PET scan result had implications for themselves and also for others.
Grill et al. 2020 [59]	A4 study and LEARN trials	Observational study	Amyloid PET	Participants in the elevated amyloid group, compared with participants who learned that they had a not elevated amyloid result, were not more likely to experience short-term increases in depression, anxiety, or suicidality
Wilde et al. 2018 [60]	N/A	Systematic review	Amyloid PET	The sparse data available suggest that disclosure of amyloid PET results has a low risk of psychological harm in the context of clinical trials, whereas both participants and professionals seem to support disclosure. More research is needed about the psychological impact of PET disclosure, and the predictive value of results at an individual level. Communication materials and strategies to support disclosure of amyloid PET results should be further developed and prospectively evaluated.
Kim and Lingler 2019 [61]	N/A	Systematic review	Amyloid PET	Provides important early insights into the psychological safety of disclosing amyloid imaging results to cognitively normal persons. Highlights the need for rigorously designed studies that address social and behavioral outcomes and extend to symptomatic populations.