Table 4.

Key findings of the impact of amyloid disclosure on caregiver outcomes

Outcome	Measure	Study	Study design	Timing of outcome	Analysis	Key Findings
Depression	Patient Health Questionnaire (PHQ-2)	Belanger (2022)	Cross-sectional	Approximately 4.5 months following disclosure	Multivariate logistic regression	No significant difference in odds of depressive symptoms by scan result
	Center for Epidemiological Studies Depression Scale (CESD)	Lingler (2020)	RCT	4, 24, and 52 weeks post-disclosure	Intention to treat using linear mixed modelling	No significant difference in depressive symptoms between caregivers to scan recipients and those who received psychoeducation. There was no significant difference in scores over time
	4 questions developed by authors Scored on a likert scale	Bensaidane (2016)	Cross-sectional	At least 30 days after amyloid disclosure	Independent samples t-test	There was no significant difference between amyloid positive and amyloid negative groups
Anxiety	Spielberger State Anxiety Inventory (STAI)	Lingler (2020)	RCT	4, 24, and 52 weeks post-disclosure	Intention to treat using linear mixed modelling	Caregivers’ anxiety levels increased from baseline at both 4 and 24 weeks of follow-up, returning to baseline at week 52. However, anxiety levels remained below the cut-off for clinical significance
		Belanger (2022)	Cross-sectional	Approximately 4.5 months following disclosure	Multivariate logistic regression	Elevated amyloid PET scan results were associated with higher levels of anxiety among caregivers of persons with MCI, even after controlling for covariates
	4 questions developed by authors Scored on a likert scale	Bensaidane (2016)	Cross-sectional	At least 30 days after amyloid disclosure	Independent samples t-test	There was no significant difference between amyloid positive and amyloid negative groups
Test related distress	Impact of Event Scale (IES)	Lingler (2020)	RCT	4, 24, and 52 weeks post-disclosure	Intention to treat using linear mixed modelling	No significant differences between caregivers to scan recipients and those who received psychoeducation. No significant differences in IES scores over time
	Distress and Positive Impact subscales of the Impact of Genetic Testing - Alzheimer’s Disease (IGT-AD)	Lingler (2020)	RCT	4, 24, and 52 weeks post-disclosure	Intention to treat using linear mixed modelling	Caregivers of persons with elevated amyloid reacted more negatively to test results on the distress and positive subscales
Quality of life	3 questions developed by authors Scored on a likert scale	Bensaidane (2016)	Cross-sectional	At least 30 days after amyloid disclosure	Independent samples t-test	There was no significant difference between amyloid positive and amyloid negative groups
Self efficacy for coping	Self efficacy for coping scale (CSE)	Lingler (2020)	RCT	4, 24, and 52 weeks post-disclosure	Intention to treat using linear mixed modelling	Decreased self-efficacy for coping was most pronounced among caregivers of persons with elevated amyloid at 4 weeks post disclosure and those of amyloid negative patients at 24 weeks post disclosure
Understanding of scan result or diagnosis	Accurate reporting of scan result	James (2020)	Cross-sectional	Approximately 4.5 months following disclosure	Chi-squared test	85% of care partners correctly reported the results of the amyloid PET scan; In 75% of dyads, both patient and care partner correctly reported results, while in 7% of dyads, both incorrectly reported results; The remaining 18% of dyads were discordant in their reporting of scan results. Caregivers to people with dementia were more likely to correctly recall the results than caregivers to people with MCI.
	MCI/AD Knowledge Assessment	Lingler (2020)	RCT	4, 24, and 52 weeks post-disclosure	Intention to treat using linear mixed modelling	Objective knowledge of MCI/AD increased from baseline among caregivers to scan recipients and those who received psychoeducation. There was no significant difference between intervention groups
	Illness coherences subscale of the revised illness perception questionnaire (IPQ-R)	Lingler (2020)	RCT	4, 24, and 52 weeks post-disclosure	Intention to treat using linear mixed modelling	There was no significant difference in perceived ambiguity of MCI between caregivers of scan recipients and those who received psychoeducation. There were no significant differences between caregivers to persons with positive and negatives scans
	6 questions developed by authors Scored on a likert scale	Bensaidane (2016)	Cross-sectional	At least 30 days after amyloid disclosure	Independent samples t-test	There was no significant difference between amyloid positive and amyloid negative groups
Expectations for future	4 questions developed by authors Scored on a likert scale	Bensaidane (2016)	Cross-sectional	At least 30 days after amyloid disclosure	Independent samples t-test	There was no significant difference between amyloid positive and amyloid negative groups
Willingness to accept risky treatment	The following question: Suppose there is a new technology that can return your memory to normal but has a risk of death. What is the highest risk of death, if any, that you would be willing to accept for this treatment? The number you give can be anywhere between 0% and 100%	Jutkowitz (2020)	Cross-sectional	Approximately 4.5 months following disclosure	Marginal effects estimated through logistic and linear regression models	On average, care partners believed the patient would accept a treatment that carried a 29.68% risk of death; 24% of dyads agreed precisely on the amount risk that would be accepted, 35% of care partners underestimated and 41% of care partners overestimated the amount of risk the patient would accept by an average of 1.65 percentage points.

Note: RCT = randomized controlled trial; PET = Positron Emission Tomography.