Current Alzheimer’s disease (AD) research initiatives focus on cognitively healthy individuals with biomarkers that are associated with the development of AD. It is unclear whether biomarker results should be returned to research participants and what the psychological, behavioural and social effects of disclosure are. A systematic review by the European Prevention of Alzheimer’s Dementia (EPAD) initiative has examined the effects of disclosing genetic and nongenetic AD-related biomarkers to cognitively healthy research participants.
A systematic literature search in eight scientific databases was performed. Fourteen studies met the inclusion criteria and were included in the data synthesis. Results extracted from the included articles were aggregated and presented per effect group. None of the identified studies examined the effects of disclosing nongenetic biomarkers. All studies but one concerned the disclosure of APOE genotype and were conducted in the US.
Study populations consisted largely of cognitively healthy first-degree relatives of people with AD.
The EPAD reviewers concluded that in cognitively healthy research participants with a first-degree relative with AD, disclosure of genetic biomarkers does not lead to elevated anxiety and depression levels, but does increase test-related distress and results in behaviour changes concerning insurance and health.
They did not find studies reporting the effects of disclosing nongenetic biomarkers and only one study included people without a family history of AD.
“Empirical studies on the effects of disclosing nongenetic biomarkers and of disclosure to persons without a family history of AD are urgently needed” they concluded.