Study Finds 40% of Research Participants Decline to Learn Results of Alzheimer Disease Biomarker Testing
The new findings are contrary to previous research that found family history of AD increases desire for testing and support the "right not to know."
Study participants who were Black and those with parental history of Alzheimer disease (AD) were significantly more likely to decline learning results of biomarker tests for AD, according to a new observational cohort study published in JAMA Network Open. The findings challenge assumptions about participant interest in receiving personal research results and highlight important demographic differences in uptake, study authors wrote.1
Researchers from Washington University Bioethics Research Center in St. Louis found that 110 of 274 participants (40%) in a longitudinal aging study declined the opportunity to learn results of research evaluating the presence of biomarkers for AD. Black participants were nearly twice as likely to decline compared to White participants (adjusted risk ratio [aRR], 1.89; 95% CI, 1.43-2.50), while those with a parental history of AD dementia were 49% more likely to decline than those without (aRR, 1.49; 95% CI, 1.12-1.98), according to the study.1
The findings "underscore the ethical importance of respecting the right not to know" first author Spondita Goswami, PhD, a staff scientist at the Bioethics Research Center and colleagues wrote, noting that previous studies consistently suggested much higher interest levels for receiving AD research results.2,3
The study, conducted between November 2020 and April 2024, involved cognitively unimpaired adults aged 65 years or older enrolled in a longitudinal cohort study of cognitive aging who had available AD biomarker data. Participants had previously been told they would not receive research results, but were offered this option through a secondary study, the Washington University Study of Having AD Research Results Explained (WeSHARE).1
AD biomarker research results: APOE genotype and either PET amyloid and magnetic resonance imaging hippocampal volume, or plasma amyloid.
Authors' qualitative interviews with a subset of 26 participants who declined results revealed several key reasons for their decision. Most commonly, participants feared that knowing would be a burden (21 participants), potentially exacerbating memory concerns or disrupting their current well-being. Many (20) also cited negative experiences with AD dementia, including painful memories of caring for affected family members.1
"I think I would live my life with some hesitation or doubt... if I was always wondering if I forgot the name of someone or the direction somewhere, that I'd be like, 'Oh my gosh, this is it. It started. I'm on the trajectory,'" one participant explained.1
Other reasons revealed included lack of treatments or perceived utility (16), feeling positive about current memory (12), concern about burdening family members (9), having already prepared for the future (8), and uncertainty about the information's value (8), according to the study.1
Goswami et al found the significant association between parental AD history and declining to learn results particularly noteworthy, as it contradicts previous research suggesting family history increases desire for testing. The qualitative data from the current study suggest that witnessing a parent's cognitive decline creates negative perceptions that discourage participants from wanting to know their own risk, they wrote.
The gap between previously reported hypothetical interest (81% in one study) and actual uptake (60% in this study) mirrors findings in other conditions. The authors cite research on Huntington Disease, where stated interest was approximately 70% but actual uptake was only 17% over a 22-year period.
The study notably found no significant association between age and the decision to decline results, although more participants in older age groups tended to decline. The type of biomarker result offered (plasma versus imaging) was significant in univariate analysis but not after adjustment for other factors, according to the results.
The findings come as return of research results (RoRR) is becoming increasingly expected in AD research, authors noted. The National Academies4 and a recent AD research participant bill of rights5 advocate for access to research results regardless of cognitive status, and the latest funding opportunity for Alzheimer's Disease Research Centers requires plans for RoRR.6
"Individuals in our study did not want to disturb their current well-being which was attributable in part to not having memory concerns currently, and a common reason they might change their mind was if they developed memory concerns in future."
The researchers acknowledge limitations, including the cohort's higher education and socioeconomic status compared to the general population, which may explain the low frequency of concerns about insurance discrimination. Additionally, while the study identified significant racial differences in uptake, the small number of Black participants in the qualitative interviews (3 of 26) limited exploration of potential differences in decision-making factors.
The authors emphasize the need for further research to better understand racial differences in uptake and ensure that the choice to receive research results reflects individual preferences. They suggest that educational materials addressing common concerns about exacerbating memory issues or burdening loved ones could help individuals make more informed choices.
As disease-modifying treatments for AD become available, the authors anticipate increased willingness to learn biomarker results but stress that respecting individual choice remains paramount. The study suggests that participants' interest in results may increase if they develop memory concerns or if additional prevention treatments become available.
