"I know what you told me, but this is what I think;" perceived risk of Alzheimer disease among individuals who accurately recall their genetics-based risk estimate

Purpose: This study evaluates the Alzheimer disease risk perceptions of individuals who accurately recall their genetics-based Alzheimer disease risk assessment.

Methods: Two hundred forty-six unaffected first-degree relatives of patients with Alzheimer disease were enrolled in a multisite randomized controlled trial examining the effects of communicating APOE genotype and lifetime Alzheimer disease risk information.

Results: Among the 158 participants who accurately recalled their Alzheimer disease risk assessment 6 weeks after risk disclosure, 75 (47.5%) believed their Alzheimer disease risk was more than 5% points different from the Alzheimer disease risk estimate they were given. Within this subgroup, 69.3% believed that their Alzheimer disease risk was higher than what they were told (discordant high), whereas 30.7% believed that their Alzheimer disease risk was lower (discordant low). Participants with a higher baseline risk perception were more likely to have a discordant-high risk perception (P < 0.05). Participants in the discordant-low group were more likely to be APOE ε4 positive (P < 0.05) and to score higher on an Alzheimer disease controllability scale (P < 0.05).

Conclusion: Our results indicate that even among individuals who accurately recall their Alzheimer disease risk assessment, many people do not take communicated risk estimates at face value. Further exploration of this clinically relevant response to risk information is warranted.