Development of a process to disclose amyloid imaging results to cognitively normal older adult research participants

Ethical Considerations for Identifying Individuals in the Prodromal/Early Phase of Parkinson's Disease: A Narrative Review

The ability to identify individuals in the prodromal phase of Parkinson's disease has improved in recent years, raising the question of whether and how those affected should be informed about the risk of future disease. Several studies investigated prognostic counselling for individuals with isolated REM sleep behavior disorder and have shown that most patients want to receive information about prognosis, but autonomy and individual preferences must be respected. However, there are still many unanswered questions about risk disclosure or early diagnosis of PD, including the impact on personal circumstances, cultural preferences and specific challenges associated with different profiles of prodromal symptoms, genetic testing or biomarker assessments. This narrative review aims to summarize the current literature on prognostic counselling and risk disclosure in PD, as well as highlight future perspectives that may emerge with the development of new biomarkers and their anticipated impact on the definition of PD.

Protocol for a double-blind placebo-controlled randomised controlled trial assessing the impact of oral semaglutide in amyloid positivity (ISAP) in community dwelling UK adults

INTRODUCTION

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs), currently marketed for type 2 diabetes and obesity, may offer novel mechanisms to delay or prevent neurotoxicity associated with Alzheimer's disease (AD). The impact of semaglutide in amyloid positivity (ISAP) trial is investigating whether the GLP-1 RA semaglutide reduces accumulation in the brain of cortical tau protein and neuroinflammation in individuals with preclinical/prodromal AD.

METHODS AND ANALYSIS

ISAP is an investigator-led, randomised, double-blind, superiority trial of oral semaglutide compared with placebo. Up to 88 individuals aged ≥55 years with brain amyloid positivity as assessed by positron emission tomography (PET) or cerebrospinal fluid, and no or mild cognitive impairment, will be randomised. People with the low-affinity binding variant of the rs6971 allele of the Translocator Protein 18 kDa (TSPO) gene, which can interfere with interpreting TSPO PET scans (a measure of neuroinflammation), will be excluded.At baseline, participants undergo tau, TSPO PET and MRI scanning, and provide data on physical activity and cognition. Eligible individuals are randomised in a 1:1 ratio to once-daily oral semaglutide or placebo, starting at 3 mg and up-titrating to 14 mg over 8 weeks. They will attend safety visits and provide blood samples to measure AD biomarkers at weeks 4, 8, 26 and 39. All cognitive assessments are repeated at week 26. The last study visit will be at week 52, when all baseline measurements will be repeated. The primary end point is the 1-year change in tau PET signal.

ETHICS AND DISSEMINATION

The study was approved by the West Midlands-Edgbaston Research Ethics Committee (22/WM/0013). The results of the study will be disseminated through scientific presentations and peer-reviewed publications.

TRIAL REGISTRATION NUMBER

ISRCTN71283871.

Immediate Reactions to Alzheimer Biomarker Disclosure in Cognitively Unimpaired Individuals in a Global Truncated Randomized Trial

Background and Objectives

Preclinical Alzheimer disease (AD) trials simultaneously test candidate treatments and the implications of disclosing biomarker information to cognitively unimpaired individuals.

Methods

The EARLY trial was a randomized, double-blind, placebo-controlled, phase 2b/3 study conducted in 143 centers across 14 countries from November 2015 to December 2018 after being stopped prematurely because of treatment-related hepatotoxicity. Participants age 60-85 years deemed cognitively unimpaired were disclosed an elevated or not elevated brain amyloid result by a certified clinician. Among 3,686 participants, 2,066 underwent amyloid imaging, 1,394 underwent CSF biomarker assessment, and 226 underwent both. Among biomarker-tested participants with at least one change score on an outcome of interest, 680 with elevated and 2,698 with not elevated amyloid were included in this analysis. We compared the Geriatric Depression Scale (GDS), the State-Trait Anxiety Scale (STAI), and the Columbia Suicide Severity Rating Scale (CSSRS) before disclosure between amyloid groups. After disclosure, we assessed for differences in the Impact of Events Scale (IES, collected 24-72 hours after disclosure), a measure of intrusive thoughts. Additional scales included the Concerns for AD scale.

Results

Among 3378 included participants, the mean (SD) age was 69.0 (5.3); most were female (60%) and White race (84%). No differences were observed before disclosure between participants with elevated and not elevated amyloid for the GDS, STAI, or CSSRS. Participants with elevated amyloid demonstrated higher Concerns for AD scores compared with participants with not elevated amyloid before disclosure. Participants with elevated amyloid demonstrated higher IES scores (9.6 [10.8] vs 5.1 [8.0]) after disclosure and increased Concerns about AD. Patterns of reactions (elevated vs not elevated) were similar for biomarker modalities, although scores were lower among those undergoing CSF compared with PET testing. Although score differences were apparent comparing geographical regions, patterns of group differences were similar.

Discussion

Although sample bias must be considered, these results suggest that amyloid disclosure resulted in increased perceived risk and mild distress in those learning an elevated result. Although this study did not assess psychological safety, observed associations intrusive thoughts and distress could be important considerations in the future clinical practice.

Alzheimer's in the modern age: Ethical challenges in the use of digital monitoring to identify cognitive changes

Pushes toward earlier detection of Alzheimer's disease (AD)-related cognitive changes are creating interest in leveraging technologies, like cellphones, that are already widespread and well-equipped for data collection to facilitate digital monitoring for AD. Studies are ongoing to identify and validate potential "digital biomarkers" that might indicate someone has or is at risk of developing AD dementia. Digital biomarkers for AD have potential as a tool in aiding more timely diagnosis, though more robust research is needed to support their validity and utility. While there are grounds for optimism, leveraging digital monitoring and informatics for cognitive changes also poses ethical challenges, related to topics such as algorithmic bias, consent, and data privacy and security. As we confront the modern era of Alzheimer's disease, individuals, companies, regulators and policymakers alike must prepare for a future in which our day-to-day interactions with technology in our daily life may identify AD-related cognitive changes.

"And Does That Necessarily Mean Absolutely Alzheimer's?" An Analysis of Questions Raised Following Amyloid PET Results Disclosure

INTRODUCTION

Amyloid PET scans provide individuals with mild cognitive impairment (MCI) information about their risk of progressing to Alzheimer's dementia (AD). Given the wide-ranging implications of this information, best practice guidelines are needed to support researchers and clinicians disclosing these high-stakes test results. To inform the development of such guidelines, this analysis aims to describe questions and concerns raised during the disclosure of amyloid PET results in the context of MCI.

METHODS

Qualitative description was performed to analyze (n = 34) transcripts of audio-recorded amyloid PET results disclosure sessions involving MCI care dyads. The analysis focused on characterizing the frequency and nature of questions raised during an open question-and-answer (Q&A) period following the return of scan results using a standardized protocol.

RESULTS

Nearly all (n = 32/34) dyads posed questions during Q&A. Questions fell within six main categories with the most common being requests for clarification regarding AD/MCI, and next steps given the result. Questions were interspersed with comments reflecting the need for emotional support. Independently administered assessments of comprehension of results showed that, following the disclosure and Q&A, 31/32 participants with MCI and 31/31 care partners scored ≥4 on a 5-point scale. The number of questions asked by care partners during Q&A positively correlated with their level of comprehension (n = 31, Spearman's r = 0.370, p = 0.040).

DISCUSSION

This analysis highlights the value of providing opportunities for patients and their family members to ask questions upon learning patients' brain amyloid status. Disclosing clinicians should be prepared to provide clarification, resources, and support to patients and families during the return of amyloid PET results.

A Pragmatic, Investigator-Driven Process for Disclosure of Amyloid PET Scan Results to ADNI-4 Research Participants

BACKGROUND

Prior studies of Alzheimer's disease (AD) biomarker disclosure have answered important questions about individuals' safety after learning and comprehending their amyloid PET results; however, these studies have typically employed highly structured disclosure protocols and focused on the psychological impact of disclosure (e.g., anxiety, depression, and suicidality) in homogeneous populations. More work is needed to develop flexible disclosure protocols and study outcomes in ethnoculturally representative samples.

METHODS

The Alzheimer's Disease Neuroimaging Initiative (ADNI) is formally incorporating amyloid PET disclosure into the newest protocol (ADNI-4). Participants across the cognitive spectrum who wish to know their amyloid PET results may learn them. The pragmatic disclosure process spans four timepoints: (1) a pre-disclosure visit, (2) the PET scan and its read, (3) a disclosure visit, and (4) a post-disclosure check-in. This process applies to all participants, with slight modifications to account for their cognitive status. In designing this process, special emphasis was placed on utilizing investigator discretion. Participant measures include perceived risk of dementia, purpose in life, and disclosure satisfaction. Investigator assessment of the disclosure visit (e.g., challenges encountered, topics discussed, etc.) is also included.

RESULTS

Data collection is ongoing. Results will allow for more robust characterization of the impact of learning amyloid PET results on individuals and describe the perspectives of investigators.

CONCLUSION

The pragmatic design of the disclosure process in ADNI-4 coupled with the novel participant and investigator data will inform future disclosure practices. This is especially important as disclosure of biomarker results expands in research and care.

Online clinical tools to support the use of new plasma biomarker diagnostic technology in the assessment of Alzheimer's disease: a narrative review

Recent advances in new diagnostic technologies for Alzheimer's disease have improved the speed and precision of diagnosis. However, accessing the potential benefits of this technology poses challenges for clinicians, such as deciding whether it is clinically appropriate to order a diagnostic test, which specific test or tests to order and how to interpret test results and communicate these to the patient and their caregiver. Tools to support decision-making could provide additional structure and information to the clinical assessment process. These tools could be accessed online, and such 'e-tools' can provide an interactive interface to support patients and clinicians in the use of new diagnostic technologies for Alzheimer's disease. We performed a narrative review of the literature to synthesize information available on this research topic. Relevant studies that provide an understanding of how these online tools could be used to optimize the clinical utility of diagnostic technology were identified. Based on these, we discuss the ways in which e-tools have been used to assist in the diagnosis of Alzheimer's disease and propose recommendations for future research to aid further development.

Perspectives From Black and White Participants and Care Partners on Return of Amyloid and Tau PET Imaging and Other Research Results

PURPOSE

Alzheimer disease (AD) biomarker testing is now common in research and approaching clinical translation. Disclosure protocols must be informed by diverse participants' perspectives on if/how the information would be useful.

METHODS

This study utilized semistructured interviews assessing interest in receiving positron emission tomography (PET) amyloid and tau results, as well as perceived risks and benefits of hypothetical PET disclosure as a function of race and participant diagnosis.

PARTICIPANTS

Participants [39% Black; 61% White; Mage =74.28 (5.98)] included 57 adults diagnosed as either cognitively healthy (58%) or with mild cognitive impairment (42%) and their respective care partners [33% Black; 67% White; Mage =66.93 (10.92)].

RESULTS

Most dyads endorsed strong interest in PET results (82.5% of both participants and partners) regardless of race or diagnosis. Black care partners were less interested in receiving the participant's results than White care partners ( χ2(4) =8.31, P =0.047). Reasons for disclosure were diverse and highly personalized, including access to treatments or clinical trials (23.2% participants; 29.8% partners), advance planning (14.3% participants; 17.5% partners), and improved health knowledge (12.5% participants; 15.8% partners). In contrast, over 80% of respondents denied any risks of disclosure.

DISCUSSION

Results suggest that predisclosure education, decisional capacity assessment, and a flexible disclosure approach are needed.

Testing for Alzheimer Disease Biomarkers and Disclosing Results Across the Disease Continuum

Three pathologic processes are characteristic of Alzheimer disease (AD): β-amyloid, hyperphosphorylated tau, and neurodegeneration. Our understanding of AD is undergoing a transformation due to our ability to measure biomarkers of these processes across different stages of cognitive impairment. There is growing interest in using AD biomarker tests in care and research and, with this, a growing need for guidance on how to return these sensitive results to patients and participants. Here, we propose a 5-step approach informed by clinical and research experience designing and implementing AD biomarker disclosure processes, extant evidence describing how individuals react to AD biomarker information, ethics, law, and the literature on breaking bad news. The clinician should (1) determine the appropriateness of AD biomarker testing and return of results for the particular patient or research participant. If testing is appropriate, the next steps are to (2) provide pretest education and seek consent for testing from the individual and their support person, (3) administer testing, (4) return the results to the individual and their support person, and (5) follow-up to promote the recipient's well-being.

Ethical issues when using digital biomarkers and artificial intelligence for the early detection of dementia

Dementia poses a growing challenge for health services but remains stigmatized and under-recognized. Digital technologies to aid the earlier detection of dementia are approaching market. These include traditional cognitive screening tools presented on mobile devices, smartphone native applications, passive data collection from wearable, in-home and in-car sensors, as well as machine learning techniques applied to clinic and imaging data. It has been suggested that earlier detection and diagnosis may help patients plan for their future, achieve a better quality of life, and access clinical trials and possible future disease modifying treatments. In this review, we explore whether digital tools for the early detection of dementia can or should be deployed, by assessing them against the principles of ethical screening programs. We conclude that while the importance of dementia as a health problem is unquestionable, significant challenges remain. There is no available treatment which improves the prognosis of diagnosed disease. Progression from early-stage disease to dementia is neither given nor currently predictable. Available technologies are generally not both minimally invasive and highly accurate. Digital deployment risks exacerbating health inequalities due to biased training data and inequity in digital access. Finally, the acceptability of early dementia detection is not established, and resources would be needed to ensure follow-up and support for those flagged by any new system. We conclude that early dementia detection deployed at scale via digital technologies does not meet standards for a screening program and we offer recommendations for moving toward an ethical mode of implementation. This article is categorized under:Application Areas > Health CareCommercial, Legal, and Ethical Issues > Ethical ConsiderationsTechnologies > Artificial Intelligence.

Analysis of Psychological Symptoms Following Disclosure of Amyloid-Positron Emission Tomography Imaging Results to Adults With Subjective Cognitive Decline

IMPORTANCE

Individuals who are amyloid-positive with subjective cognitive decline and clinical features increasing the likelihood of preclinical Alzheimer disease (SCD+) are at higher risk of developing dementia. Some individuals with SCD+ undergo amyloid-positron emission tomography (PET) as part of research studies and frequently wish to know their amyloid status; however, the disclosure of a positive amyloid-PET result might have psychological risks.

OBJECTIVE

To assess the psychological outcomes of the amyloid-PET result disclosure in individuals with SCD+ and explore which variables are associated with a safer disclosure in individuals who are amyloid positive.

DESIGN, SETTING, AND PARTICIPANTS

This prospective, multicenter study was conducted as part of The Amyloid Imaging to Prevent Alzheimer Disease Diagnostic and Patient Management Study (AMYPAD-DPMS) (recruitment period: from April 2018 to October 2020). The setting was 5 European memory clinics, and participants included patients with SCD+ who underwent amyloid-PET. Statistical analysis was performed from July to October 2022.

EXPOSURES

Disclosure of amyloid-PET result.

MAIN OUTCOMES AND MEASURES

Psychological outcomes were defined as (1) disclosure related distress, assessed using the Impact of Event Scale-Revised (IES-R; scores of at least 33 indicate probable presence of posttraumatic stress disorder [PTSD]); and (2) anxiety and depression, assessed using the Hospital Anxiety and Depression scale (HADS; scores of at least 15 indicate probable presence of severe mood disorder symptoms).

RESULTS

After disclosure, 27 patients with amyloid-positive SCD+ (median [IQR] age, 70 [66-74] years; gender: 14 men [52%]; median [IQR] education: 15 [13 to 17] years, median [IQR] Mini-Mental State Examination [MMSE] score, 29 [28 to 30]) had higher median (IQR) IES-R total score (10 [2 to 14] vs 0 [0 to 2]; P < .001), IES-R avoidance (0.00 [0.00 to 0.69] vs 0.00 [0.00 to 0.00]; P < .001), IES-R intrusions (0.50 [0.13 to 0.75] vs 0.00 [0.00 to 0.25]; P < .001), and IES-R hyperarousal (0.33 [0.00 to 0.67] vs 0.00 [0.00 to 0.00]; P < .001) scores than the 78 patients who were amyloid-negative (median [IQR], age, 67 [64 to 74] years, 45 men [58%], median [IQR] education: 15 [12 to 17] years, median [IQR] MMSE score: 29 [28 to 30]). There were no observed differences between amyloid-positive and amyloid-negative patients in the median (IQR) HADS Anxiety (-1.0 [-3.0 to 1.8] vs -2.0 [-4.8 to 1.0]; P = .06) and Depression (-1.0 [-2.0 to 0.0] vs -1.0 [-3.0 to 0.0]; P = .46) deltas (score after disclosure - scores at baseline). In patients with amyloid-positive SCD+, despite the small sample size, higher education was associated with lower disclosure-related distress (ρ = -0.43; P = .02) whereas the presence of study partner was associated with higher disclosure-related distress (W = 7.5; P = .03). No participants with amyloid-positive SCD+ showed probable presence of PTSD or severe anxiety or depression symptoms at follow-up.

CONCLUSIONS AND RELEVANCE

The disclosure of a positive amyloid-PET result to patients with SCD+ was associated with a bigger psychological change, yet such change did not reach the threshold for clinical concern.

Understanding Online Registry Facilitators and Barriers Experienced by Black Brain Health Registry Participants: The Community Engaged Digital Alzheimer's Research (CEDAR) Study

BACKGROUND

Failure of Alzheimer's disease and related diseases (ADRD) research studies to include and engage Black participants is a major issue, which limits the impact and generalizability of research findings. Little is known about participation of Black adults in online ADRD-related research registries.

OBJECTIVES

As part of the Community Engaged Digital Alzheimer's Research (CEDAR) Study, this study aims to increase our understanding of facilitators and barriers of Black adults to participating in ADRD-related online registries, as well as to understand their preferences for communication channels.

DESIGN, SETTING, PARTICIPANTS, MEASUREMENTS

We invited all Black participants enrolled in the Brain Health Registry (BHR) to complete a cross-sectional online survey. The survey consisted of rating scales and open-text questions asking about their attitudes towards brain health research, reasons for joining and continuing to participate in BHR, difficulties with participating, and preferences for modes of contact and website usage.

RESULTS

Of all invited Black BHR participants (N=3,636), 198 (5.5%) completed the survey. The mean age was 58.4 (SD=11.3), mean years of education were 16.3 (SD=2.4), and 85.5% identified as female. Reported facilitators for joining and continuing to participate in BHR were personal interest (e.g., learning more about own brain health) and altruism (e.g., helping research). Among additional registry features which could encourage return, receiving feedback or scores about BHR tasks was rated the highest. Of those who found BHR participation difficult (21%), the most frequent reason was time burden. The most preferred way of receiving study information was via email. Participants reported that the websites that they used the most were YouTube and Facebook.

DISCUSSION

The results of our study can inform the development of culturally-responsive registry features and engagement efforts to improve inclusion and participation of Black adults in online ADRD research. Providing participants with feedback about their registry performance and reducing the number of registry tasks are among the recommended strategies.

Imaging Biomarkers for Central Nervous System Drug Development and Future Clinical Utility: Lessons from Neurodegenerative Disorders

Diseases of the central nervous system are common and often chronic conditions associated with significant morbidity. In particular, neurodegenerative disorders including Alzheimer and Parkinson disease constitute a major health and socioeconomic challenge, with an increasing incidence in many industrialized countries with aging populations. Recent work has established the primary role of abnormal protein accumulation and the spread of disease-specific deposits in brain as a factor in neurotoxicity and disruption of functional networks. A range of therapeutics from small molecules to antibodies targeting these proteinopathies are now in phase 2 and phase 3 clinical trials. These studies are methodologically challenging because of difficulty in accurately diagnosing early disease, the slow and variable rates of progression between individuals, and efficacy measures that may be cofounded by symptomatic improvements due to treatment but not reflecting disease course modification. Further, the ideal candidates for these treatments would be at-risk, or premanifest, persons in whom the pathologic process of the neurodegenerative disorder has begun but who are clinically normal and extremely difficult to identify. Scintigraphic imaging with PET and SPECT in trials offers the opportunity to interrogate pathophysiologic processes such as protein deposition with high specificity. This review summarizes the current implementation of these imaging biomarkers and the implications for future management of neurodegenerative disorders and central nervous system drug development in general.

Ethical Frameworks for Disclosure of Alzheimer Disease Biomarkers to Research Participants: Conflicting Norms and a Nuanced Policy

More and more frequently, clinical trials for Alzheimer disease (AD) are targeting cognitively unimpaired individuals who are at increased risk of developing the disease. It is not always clear whether AD biomarker information should be disclosed to research participants: on the one hand, research participants may be interested in learning this information because of its perceived utility, but on the other hand, learning this information may be harmful, as there are very few effective preventive or therapeutic options available for AD. In this article, we bring together three separate sets of ethical guidance literature: on the return of individual research results, on an individual's right to access personal data, and on transparent enrollment into clinical trials. Based on these literatures, we suggest policies for the disclosure of AD biomarker test results in longitudinal observational cohort studies, clinical trials, and hybrid research projects, such as the European Prevention of Alzheimer's Dementia (EPAD) project, in which we served as an ethics team. We also present and critically discuss recommendations for disclosure of AD biomarkers in practice. We underscore that, as long as the clinical validity of AD biomarkers remains limited, there are good reasons to avoid actively disclosing them to cognitively unimpaired research participants.

Moving beyond disclosure: Stages of care in preclinical Alzheimer's disease biomarker testing

Alzheimer's disease (AD) begins with an asymptomatic "preclinical" phase, in which abnormal biomarkers indicate risk for developing cognitive impairment. Biomarker information is increasingly being disclosed in research settings, and is moving toward clinical settings with the development of cheaper and non-invasive testing. Limited research has focused on the safety and psychological effects of disclosing biomarker results to cognitively unimpaired adults. However, less is known about how to ensure equitable access and robust counseling for decision-making before testing, and how to effectively provide long-term follow-up and risk management after testing. Using the framework of Huntington's disease, which is based on extensive experience with disclosing and managing risk for a progressive neurodegenerative condition, this article proposes a conceptual model of pre-disclosure, disclosure, and post-disclosure phases for AD biomarker testing. Addressing research questions in each phase will facilitate the transition of biomarker testing into clinical practice.

Preventing amyotrophic lateral sclerosis: insights from pre-symptomatic neurodegenerative diseases

Significant progress has been made in understanding the pre-symptomatic phase of amyotrophic lateral sclerosis. While much is still unknown, advances in other neurodegenerative diseases offer valuable insights. Indeed, it is increasingly clear that the well-recognized clinical syndromes of Alzheimer's disease, Parkinson's disease, Huntington's disease, spinal muscular atrophy and frontotemporal dementia are also each preceded by a pre-symptomatic or prodromal period of varying duration, during which the underlying disease process unfolds, with associated compensatory changes and loss of inherent system redundancy. Key insights from these diseases highlight opportunities for discovery in amyotrophic lateral sclerosis. The development of biomarkers reflecting amyloid and tau has led to a shift in defining Alzheimer's disease based on inferred underlying histopathology. Parkinson's disease is unique among neurodegenerative diseases in the number and diversity of non-genetic biomarkers of pre-symptomatic disease, most notably REM sleep behaviour disorder. Huntington's disease benefits from an ability to predict the likely timing of clinically manifest disease based on age and CAG-repeat length alongside reliable neuroimaging markers of atrophy. Spinal muscular atrophy clinical trials have highlighted the transformational value of early therapeutic intervention, and studies in frontotemporal dementia illustrate the differential role of biomarkers based on genotype. Similar advances in amyotrophic lateral sclerosis would transform our understanding of key events in pathogenesis, thereby dramatically accelerating progress towards disease prevention. Deciphering the biology of pre-symptomatic amyotrophic lateral sclerosis relies on a clear conceptual framework for defining the earliest stages of disease. Clinically manifest amyotrophic lateral sclerosis may emerge abruptly, especially among those who harbour genetic mutations associated with rapidly progressive amyotrophic lateral sclerosis. However, the disease may also evolve more gradually, revealing a prodromal period of mild motor impairment preceding phenoconversion to clinically manifest disease. Similarly, cognitive and behavioural impairment, when present, may emerge gradually, evolving through a prodromal period of mild cognitive impairment or mild behavioural impairment before progression to amyotrophic lateral sclerosis. Biomarkers are critically important to studying pre-symptomatic amyotrophic lateral sclerosis and essential to efforts to intervene therapeutically before clinically manifest disease emerges. The use of non-genetic biomarkers, however, presents challenges related to counselling, informed consent, communication of results and limited protections afforded by existing legislation. Experiences from pre-symptomatic genetic testing and counselling, and the legal protections against discrimination based on genetic data, may serve as a guide. Building on what we have learned-more broadly from other pre-symptomatic neurodegenerative diseases and specifically from amyotrophic lateral sclerosis gene mutation carriers-we present a road map to early intervention, and perhaps even disease prevention, for all forms of amyotrophic lateral sclerosis.

Predicting Symptom Onset in Sporadic Alzheimer's Disease: "How Long Do I Have?"

Predicting not just if but when cognitively normal individuals will develop the onset of Alzheimer's disease (AD) dementia seems increasingly feasible, as evidenced by converging findings from several approaches and cohorts. These estimates may improve the efficiency of clinical trials by better identifying cognitively normal individuals at high risk of developing AD symptoms. As models are refined, the implications of disclosing estimates of the age of AD symptom onset must be examined, since telling a cognitively normal individual the age they are expected to develop AD symptoms may have different implications than disclosing increased risk for AD dementia.

Digital phenotyping and the (data) shadow of Alzheimer's disease

In this paper, we examine the practice and promises of digital phenotyping. We build on work on the 'data self' to focus on a medical domain in which the value and nature of knowledge and relations with data have been played out with particular persistence, that of Alzheimer's disease research. Drawing on research with researchers and developers, we consider the intersection of hopes and concerns related to both digital tools and Alzheimer's disease using the metaphor of the 'data shadow'. We suggest that as a tool for engaging with the nature of the data self, the shadow is usefully able to capture both the dynamic and distorted nature of data representations, and the unease and concern associated with encounters between individuals or groups and data about them. We then consider what the data shadow 'is' in relation to ageing data subjects, and the nature of the representation of the individual's cognitive state and dementia risk that is produced by digital tools. Second, we consider what the data shadow 'does', through researchers and practitioners' discussions of digital phenotyping practices in the dementia field as alternately empowering, enabling and threatening.

Family members' perspectives on learning cognitively unimpaired older adults' amyloid-β PET scan results

BACKGROUND/OBJECTIVES

Disclosure of Alzheimer's disease (AD) risk information to cognitively unimpaired older adults may become more common if preclinical AD is shown to be identifiable and amenable to treatment. Little, however, is known about how families will react to this information.

DESIGN AND SETTING

Semi-structured telephonic interviews.

PARTICIPANTS

Seventy study partners (mean age = 68 [±11]; 50% female; 70% spouses/significant others; 18% children, siblings; 12% friends) of cognitively unimpaired adults who learned a personalized AD dementia risk estimate and an amyloid-β PET scan result through their participation in preclinical AD research.

MEASUREMENT

Interviewees were asked about their desire for information regarding their family member's AD dementia risk, baseline expectations of risk, understanding of amyloid-β PET scan results, and the impact of AD dementia risk information on emotions, health behaviors, and future plans, as well as on perceptions of their family member's or friend's memory.

RESULTS

Interviewees generally understood the AD dementia risk information (83%) and considered it valuable (75%). Risk information perceived as favorable elicited feelings of happiness and relief; unfavorable information elicited disappointment, as well as increased awareness of the participants' memory and monitoring for incipient changes in cognition. While noting that AD dementia risk information was not medically actionable at this time due to the lack of disease-modifying therapies, some interviewees described changes to their family members' and their own health behaviors and future plans.

CONCLUSION

Guidelines for the disclosure of AD dementia risk estimates and biomarker results to cognitively unimpaired adults should account for the needs and interests of individuals and their family members, who may step into a pre-caregiver role.

Brain Health Services: organization, structure, and challenges for implementation. A user manual for Brain Health Services-part 1 of 6

Dementia has a devastating impact on the quality of life of patients and families and comes with a huge cost to society. Dementia prevention is considered a public health priority by the World Health Organization. Delaying the onset of dementia by treating associated risk factors will bring huge individual and societal benefit. Empirical evidence suggests that, in higher-income countries, dementia incidence is decreasing as a result of healthier lifestyles. This observation supports the notion that preventing dementia is possible and that a certain degree of prevention is already in action. Further reduction of dementia incidence through deliberate prevention plans is needed to counteract its growing prevalence due to increasing life expectancy.An increasing number of individuals with normal cognitive performance seek help in the current memory clinics asking an evaluation of their dementia risk, preventive interventions, or interventions to ameliorate their cognitive performance. Consistent evidence suggests that some of these individuals are indeed at increased risk of dementia. This new health demand asks for a shift of target population, from patients with cognitive impairment to worried but cognitively unimpaired individuals. However, current memory clinics do not have the programs and protocols in place to deal with this new population.We envision the development of new services, henceforth called Brain Health Services, devoted to respond to demands from cognitively unimpaired individuals concerned about their risk of dementia. The missions of Brain Health Services will be (i) dementia risk profiling, (ii) dementia risk communication, (iii) dementia risk reduction, and (iv) cognitive enhancement. In this paper, we present the organizational and structural challenges associated with the set-up of Brain Health Services.

Dementia risk communication. A user manual for Brain Health Services-part 3 of 6

Growing evidence suggests dementia incidence can be reduced through prevention programs targeting risk factors. To accelerate the implementation of such prevention programs, a new generation of brain health services (BHS) is envisioned, involving risk profiling, risk communication, risk reduction, and cognitive enhancement. The purpose of risk communication is to enable individuals at risk to make informed decisions and take action to protect themselves and is thus a crucial step in tailored prevention strategies of the dementia incidence. However, communicating about dementia risk is complex and challenging.In this paper, we provide an overview of (i) perspectives on communicating dementia risk from an ethical, clinical, and societal viewpoint; (ii) insights gained from memory clinical practice; (iii) available evidence on the impact of disclosing APOE and Alzheimer's disease biomarker test results gathered from clinical trials and observational studies; (iv) the value of established registries in light of BHS; and (v) practical recommendations regarding effective strategies for communicating about dementia risk.In addition, we identify challenges, i.e., the current lack of evidence on what to tell on an individual level-the actual risk-and on how to optimally communicate about dementia risk, especially concerning worried yet cognitively unimpaired individuals. Ideally, dementia risk communication strategies should maximize the desired impact of risk information on individuals' understanding of their health/disease status and risk perception and minimize potential harms. More research is thus warranted on the impact of dementia risk communication, to (1) evaluate the merits of different approaches to risk communication on outcomes in the cognitive, affective and behavioral domains, (2) develop an evidence-based, harmonized dementia risk communication protocol, and (3) develop e-tools to support and promote adherence to this protocol in BHSs.Based on the research reviewed, we recommend that dementia risk communication should be precise; include the use of absolute risks, visual displays, and time frames; based on a process of shared decision-making; and address the inherent uncertainty that comes with any probability.

Communicating 5-Year Risk of Alzheimer's Disease Dementia: Development and Evaluation of Materials that Incorporate Multiple Genetic and Biomarker Research Results

BACKGROUND

Cognitively normal (CN) older adults participating in Alzheimer's disease (AD) research increasingly ask for their research results-including genetic and neuroimaging findings-to understand their risk of developing AD dementia. AD research results are typically not returned for multiple reasons, including possible psychosocial harms of knowing one is at risk of a highly feared and untreatable disease.

OBJECTIVE

We developed materials that convey information about 5-year absolute risk of developing AD dementia based on research results.

METHODS

20 CN older adults who received a research brain MRI result were interviewed regarding their wishes for research results to inform material development (Pilot 1). Following material development, 17 CN older adults evaluated the materials for clarity and acceptability (Pilot 2). All participants were community-dwelling older adults participating in longitudinal studies of aging at a single site.

RESULTS

Participants want information on their risk of developing AD dementia to better understand their own health, satisfy curiosity, inform family, and future planning. Some articulated concerns, but the majority wanted to know their risk despite the limitations of information. Participants found the educational materials and results report clear and acceptable, and the majority would want to know their research results after reviewing them.

CONCLUSION

These materials will be used in a clinical study examining the psychosocial and cognitive effects of offering research results to a cohort of CN older adults. Future AD research may incorporate the return of complex risk information to CN older adults, and materials are needed to communicate this information.

Reasons for undergoing amyloid imaging among cognitively unimpaired older adults

OBJECTIVES

Preclinical Alzheimer's disease (AD) clinical trials screen cognitively unimpaired older adults for biomarker criteria and disclose their results. We examined whether participants in the Anti-Amyloid Treatment in Asymptomatic Alzheimer's disease Study with "elevated" and "not elevated" amyloid differed in scores on the "Views and Perceptions of Amyloid Imaging" questionnaire. We hypothesized that, prior to disclosure, those with elevated amyloid would score higher than those with not elevated amyloid. We also quantified how responses changed after result disclosure.

METHODS

We assessed data from 4327 individuals who completed the questionnaire at screening visit 1 and after amyloid disclosure. We used linear regression models to assess the relationship between questionnaire category scores and amyloid status. We also quantified the relationship between category score changes and amyloid status.

RESULTS

Overall, participants scored altruism and contribution to research as the strongest motivations for undergoing amyloid imaging. Those with elevated amyloid scored 0.23 points higher in the Perceived Risk category, on average, than those who had not elevated amyloid prior to disclosure; this effect attenuated towards zero after adjusting for Cognitive Function Instrument score. After disclosure, participants with elevated amyloid demonstrated less within-subject change in Perceived Risk, on average, compared to those with similar pre-disclosure scores who had not elevated amyloid, while demonstrating greater changes in the altruism and planning categories.

INTERPRETATION

Altruism and learning disease risk motivated enrollment in this preclinical AD trial. Participants with elevated amyloid differed from their not elevated counterparts in their perceptions of amyloid imaging, even before undergoing the procedure.

Caregiver reactions to neuroimaging evidence of covert consciousness in patients with severe brain injury: a qualitative interview study

Background

Severe brain injury is a leading cause of death and disability. Diagnosis and prognostication are difficult, and errors occur often. Novel neuroimaging methods can improve diagnostic and prognostic accuracy, especially in patients with prolonged disorders of consciousness (PDoC). Yet it is currently unknown how family caregivers understand this information, raising ethical concerns that disclosure of neuroimaging results could result in therapeutic misconception or false hope.

Methods

To examine these ethical concerns, we conducted semi-structured interviews with caregivers of patients with PDoC who were enrolled in a concurrent neuroimaging research program designed to detect covert consciousness following severe brain injury. Caregivers held surrogate decision-making status for a patient. Interviews were conducted at two time points for each caregiver. The first interview occurred before the disclosure of neuroimaging results. The second occurred after disclosure. Descriptive analysis was applied to the data of four interview topics: (1) expectations for neuroimaging; (2) reactions to evidence of preserved cognition; (3) reactions to null results; and (4) understanding of the results and study.

Results

Twelve caregivers participated in the study; two caregivers shared surrogate decision-making status for one patient with PDoC. Twenty-one interviews were completed; one caregiver declined to participate in the post-disclosure interview. Three patients with PDoC associated with the study displayed evidence of covert consciousness. Overall, caregivers understood the neuroimaging research and results. Caregivers who received results of covert consciousness were generally pleased. However, there was some variation in expectations and reactions to these data and null results.

Conclusion

This study, for the first time, reveals caregiver expectations for and reactions to neuroimaging evidence of covert consciousness in patients with PDoC. Caregivers understood the neuroimaging research and results, casting doubt on speculative ethical concerns regarding therapeutic misconception and false hope. However, disclosure of neuroimaging result could be improved. Pre-disclosure consultations might assist professionals in shaping caregiver expectations. Standardization of disclosure might also improve comprehension of the results.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12910-021-00674-8.

The Framing of "Alzheimer's Disease": Differences Between Scientific and Lay Literature and Their Ethical Implications

BACKGROUND AND OBJECTIVES

The meaning of Alzheimer's disease (AD) is changing in research. It now refers to a pathophysiological process, regardless of whether clinical symptoms are present. In the lay literature, on the other hand, AD is understood as a form of dementia. This raises the question of whether researchers and the lay audience are still talking about the same thing. If not, how will these different understandings of AD shape perspectives on (societal) needs for people with AD?

RESEARCH DESIGN AND METHODS

We use framing analysis to retrieve the understandings of the term AD that are upheld in the research literature and in national Dutch newspaper articles. We make explicit how the framings of AD steer our normative attitudes toward the disease.

RESULTS

In the analyzed research articles, AD is framed as a pathological cascade, reflected by biomarkers, starting in cognitively healthy people and ending, inevitably, in dementia. In the lay literature, AD is used as a synonym for dementia, and an AD diagnosis is understood as an incentive to enjoy "the time that is left."

DISCUSSION AND IMPLICATIONS

The two different uses of the term AD in research and in the lay literature may result in misunderstandings, especially those research framings that falsely imply that people with AD biomarkers will inevitably develop dementia. Adoption of the research understanding of AD in clinical practice will have normative implications for our view on priority setting in health care. For example, it legitimizes biomarker testing in people without dementia as improving "diagnostic" certainty.

Short-term Psychological Outcomes of Disclosing Amyloid Imaging Results to Research Participants Who Do Not Have Cognitive Impairment

Importance

The goal of preclinical Alzheimer disease (AD) clinical trials is to move diagnosis and treatment to presymptomatic stages, which will require biomarker testing and disclosure.

Objective

To assess the short-term psychological outcomes of disclosing amyloid positron emission tomography results to older adults who did not have cognitive impairment.

Design, Setting, and Participants

This observational study included participants who were screening for a multisite randomized clinical trial that began on February 28, 2014, and is anticipated to be completed in 2022. Participants aged 65 to 85 years who had no known cognitive impairments underwent an amyloid positron emission tomography scan and learned their result from an investigator who used a protocol-specified process that included prescan education and psychological assessments. This report compares participants with elevated amyloid levels with at least 1 available outcome measure with participants who did not have elevated amyloid levels who enrolled in an observational cohort study and received further evaluations. Data were collected from April 2014 to December 2017 and analyzed from March 2019 to October 2019.

Exposures

A personal biomarker result described as either an elevated or not elevated amyloid level.

Main Outcomes and Measures

To assess the immediate and short-term psychological outcome of disclosure, the following validated measures were used: the Geriatric Depression Scale, the state items from the State-Trait Anxiety Inventory, and the Columbia Suicide Severity Rating Scale, as well as the Concerns About AD Scale and the Future Time Perspective Scale to assess changes in participants' perceived risk for AD and perceived remaining life span, respectively.

Results

A total of 1167 participants with elevated amyloid levels and 538 participants with not elevated amyloid levels were included. Participants had a mean (SD) age of 71.5 (4.7) years, 1025 (60.1%) were women, and most were white (1611 [94.5%]) and non-Latino (1638 [96.1%]). Compared with participants who learned that they had a not elevated amyloid result, individuals who learned of an elevated amyloid result were no more likely to experience short-term increases in depression (mean [SD] change in the Geriatric Depression Scale score, 0.02 [1.3] vs 0.04 [1.3]; P = .90), anxiety (mean [SD] change in State-Trait Anxiety Inventory score, -0.02 [3.2] vs -0.15 [3.0]; P = .65), or suicidality (mean [SD] change in the Columbia Suicide Severity Rating Scale score, 0.0 [0.4] vs -0.01 [0.5]; P = .67). Participants with elevated amyloid levels had increased Concern About AD scores (raw change in scores: elevated amyloid group, 0.8 [3.9]; not elevated amyloid group, -0.4 [3.8]; P < .001). Participants with not elevated amyloid levels experienced a slight increase in Future Time Perspective score(mean [SD] score, 1.15 [7.4] points; P < .001); there was no change in time perspective among those receiving an elevated amyloid result (mean [SD] score, 0.33 [7.8] points).

Conclusions and Relevance

In this observational preclinical AD study, participants who learned they had elevated amyloid levels did not experience short-term negative psychological sequelae compared with persons who learned they did not have elevated amyloid levels.

Ethical Considerations in Communicating Alzheimer's Disease Neuroimaging Biomarker Test Results to Symptomatic Individuals

This article examines ethical issues associated with the return of AD neuroimaging results to cognitively symptomatic individuals. Following a review of research on patient and study partner reactions to learning the results of biomarker testing for AD, we examine ethical issues that will be of increasing significance as the field transitions to an era wherein disease-modifying treatments for AD become available. We first review the ethical justification for returning AD biomarker results to individuals who desire them. We then address a more novel question: whether, and to what extent, clinicians or clinical researchers should influence the decisions of individuals who are potentially reluctant to learn their AD imaging results. We argue that in many cases, it is ethically correct to explore, and sometimes alter, factors that may be inhibiting one's desire to know these test results. Our argument is grounded in the premise that having more complete information about changes that may be happening in one's brain will generally yield more informed participation in decisions about one's own care, thereby promoting autonomy. Finally, on the assumption that we have established that it is frequently ethically correct to try to communicate testing information, we examine considerations regarding (not whether but) how this is best accomplished, discussing the concept of responsible transparency. We suggest that both (1) explorations of why one may or may not want to learn results of AD biomarker imaging and (2) the responsible return of such test results is best accomplished using a transactional model of communication.

The full spectrum of ethical issues in dementia research: findings of a systematic qualitative review

BACKGROUND

When including participants with dementia in research, various ethical issues arise. At present, there are only a few existing dementia-specific research guidelines (Committee for Medicinal Products for Human Use in Clinical investigation of medicines for the treatment Alzheimer's disease (Internet). https://www.ema.europa.eu/en/clinical-investigation-medicines-treatment-alzheimers-disease ; Food and Drug Administration, Early Alzheimer's Disease: Developing Drugs for Treatment Guidance for Industry [Internet]. http://www.fda.gov/regulatory-information/search-fda-guidance-documents/alzheimers-disease-developing-drugs-treatment-guidance-industy ), necessitating a more systematic and comprehensive approach to this topic to help researchers and stakeholders address dementia-specific ethical issues in research. A systematic literature review provides information on the ethical issues in dementia-related research and might therefore serve as a basis to improve the ethical conduct of this research. This systematic review aims to provide a broad and unbiased overview of ethical issues in dementia research by reviewing, analysing, and coding the latest literature on the topic.

METHODS

We conducted a systematic review in PubMed and Google Scholar (publications in English between 2007 and 2020, no restrictions on the type of publication) of literature on research ethics in dementia research. Ethical issues in research were identified by qualitative text analysis and normative analysis.

RESULTS

The literature review retrieved 110 references that together mentioned 105 ethical issues in dementia research. This set of ethical issues was structured into a matrix based on the eight major principles from a pre-existing framework on biomedical ethics (Emanuel et al. An Ethical Framework for Biomedical Research. in The Oxford textbook of clinical research ethics, Oxford University Press, Oxford, 2008). Consequently, subcategories were created and further categorized into dementia stages and study phases.

CONCLUSIONS

The systematically derived matrix helps raise awareness and understanding of the complex topic of ethical issues in dementia research. The matrix can be used as a basis for researchers, policy makers and other stakeholders when planning, conducting and monitoring research, making decisions on the legal background of the topic, and creating research practice guidelines.

Biomarker-Based Risk Prediction of Alzheimer’s Disease Dementia in Mild Cognitive Impairment: Psychosocial, Ethical, and Legal Aspects

Background: Today, a growing number of individuals with mild cognitive impairment (MCI) wish to assess their risk of developing Alzheimer’s disease (AD) dementia. The expectations as well as the effects on quality of life (QoL) in MCI patients and their close others through biomarker-based dementia risk estimation are not well studied. Objective: The PreDADQoL project aims at providing empirical data on effects of such prediction on QoL and at developing an ethical and legal framework of biomarker-based dementia risk estimation in MCI. Methods: In the empirical study, 100 MCI-patients and their close others will be recruited from two sites (Germany and Spain). They receive standardized counselling on cerebrospinal fluid (CSF) biomarker-based prediction of AD dementia and a risk disclosure based on their AD biomarker status. A mixed methods approach will be applied to assess outcomes. Results: The pilot-study yielded a specification of the research topics and newly developed questionnaires for the main assessment. Within this binational quantitative and qualitative study, data on attitudes and expectations toward AD risk prediction, QoL, risk communication, coping strategies, mental health, lifestyle changes, and healthcare resource utilization will be obtained. Together with the normative part of the project, an empirically informed ethical and legal framework for biomarker-based dementia risk estimation will be developed. Conclusion: The empirical research of the PreDADQoL study together with the ethical and legal considerations and implications will help to improve the process of counselling and risk disclosure and thereby positively affect QoL and health of MCI-patients and their close others in the context of biomarker-based dementia risk estimation.

Population-based blood screening for preclinical Alzheimer's disease in a British birth cohort at age 70

Alzheimer's disease has a preclinical stage when cerebral amyloid-β deposition occurs before symptoms emerge, and when amyloid-β-targeted therapies may have maximum benefits. Existing amyloid-β status measurement techniques, including amyloid PET and CSF testing, are difficult to deploy at scale, so blood biomarkers are increasingly considered for screening. We compared three different blood-based techniques-liquid chromatography-mass spectrometry measures of plasma amyloid-β, and single molecule array (Simoa) measures of plasma amyloid-β and phospho-tau181-to detect cortical 18F-florbetapir amyloid PET positivity (defined as a standardized uptake value ratio of >0.61 between a predefined cortical region of interest and eroded subcortical white matter) in dementia-free members of Insight 46, a substudy of the population-based British 1946 birth cohort. We used logistic regression models with blood biomarkers as predictors of amyloid PET status, with or without age, sex and APOE ε4 carrier status as covariates. We generated receiver operating characteristics curves and quantified areas under the curves to compare the concordance of the different blood tests with amyloid PET. We determined blood test cut-off points using Youden's index, then estimated numbers needed to screen to obtain 100 amyloid PET-positive individuals. Of the 502 individuals assessed, 441 dementia-free individuals with complete data were included; 82 (18.6%) were amyloid PET-positive. The area under the curve for amyloid PET status using a base model comprising age, sex and APOE ε4 carrier status was 0.695 (95% confidence interval: 0.628-0.762). The two best-performing Simoa plasma biomarkers were amyloid-β42/40 (0.620; 0.548-0.691) and phospho-tau181 (0.707; 0.646-0.768), but neither outperformed the base model. Mass spectrometry plasma measures performed significantly better than any other measure (amyloid-β1-42/1-40: 0.817; 0.770-0.864 and amyloid-β composite: 0.820; 0.775-0.866). At a cut-off point of 0.095, mass spectrometry measures of amyloid-β1-42/1-40 detected amyloid PET positivity with 86.6% sensitivity and 71.9% specificity. Without screening, to obtain 100 PET-positive individuals from a population with similar amyloid PET positivity prevalence to Insight 46, 543 PET scans would need to be performed. Screening using age, sex and APOE ε4 status would require 940 individuals, of whom 266 would proceed to scan. Using mass spectrometry amyloid-β1-42/1-40 alone would reduce these numbers to 623 individuals and 243 individuals, respectively. Across a theoretical range of amyloid PET positivity prevalence of 10-50%, mass spectrometry measures of amyloid-β1-42/1-40 would consistently reduce the numbers proceeding to scans, with greater cost savings demonstrated at lower prevalence.

Disclosure of preclinical Alzheimer's disease biomarker results in research and clinical settings: Why, how, and what we still need to know

Disclosure of personal disease-related information to asymptomatic adults has been debated over the last century in medicine and research. Recently, Alzheimer's disease (AD) has been conceptualized as a continuum that begins with a "preclinical" stage in which biomarkers are present in the absence of cognitive impairment. Studies have begun assessing the safety, psychological, and behavioral effects of disclosing both AD-related genetic and biomarker information to cognitively unimpaired older adults. Yet, debate continues over the appropriate circumstances and methods for returning such information. This article outlines concerns with and rationale for AD biomarker disclosure and summarizes findings from prior studies. Overall, this article aims to describe and respond to key questions concerning disclosure of amyloid positron emission tomography scan results to asymptomatic adults in a research setting. Moving forward, such conditions are important to consider as interventions target the preclinical phase of AD and normalize disclosing biomarker information to cognitively unimpaired persons.

Association of Factors With Elevated Amyloid Burden in Clinically Normal Older Individuals

Importance

The Anti-Amyloid Treatment in Asymptomatic Alzheimer disease (A4) Study is an ongoing prevention trial in clinically normal older individuals with evidence of elevated brain amyloid. The large number of participants screened with amyloid positron emission tomography (PET) and standardized assessments provides an unprecedented opportunity to evaluate factors associated with elevated brain amyloid.

Objective

To investigate the association of elevated amyloid with demographic and lifestyle factors, apolipoprotein E (APOE), neuropsychological testing, and self- and study partner reports of cognitive function.

Design, Setting, and Participants

This cross-sectional study included screening data in the Anti-Amyloid Treatment in Asymptomatic Alzheimer Disease (A4) Study collected from April 2014 to December 2017 and classified by amyloid status. Data were was analyzed from 2018 to 2019 across 67 sites in the US, Canada, Australia, and Japan and included 4486 older individuals (age 65-85 years) who were eligible for amyloid PET (clinically normal [Clinical Dementia Rating = 0] and cognitively unimpaired [Mini-Mental State Examination score, ≥25; logical memory IIa 6-18]).

Main Outcomes and Measures

Screening demographics, lifestyle variables, APOE genotyping, and cognitive testing (Preclinical Alzheimer Cognitive Composite), self- and study partner reports of high-level daily cognitive function (Cognitive Function Index). Florbetapir amyloid PET imaging was used to classify participants as having elevated amyloid (Aβ+) or not having elevated amyloid (Aβ-).

Results

Amyloid PET results were acquired for 4486 participants (mean [SD] age, 71.29 [4.67] years; 2647 women [59%]), with 1323 (29.5%) classified as Aβ+. Aβ+ participants were slightly older than Aβ-, with no observed differences in sex, education, marital or retirement status, or any self-reported lifestyle factors. Aβ+ participants were more likely to have a family history of dementia (3320 Aβ+ [74%] vs 3050 Aβ- [68%]) and at least 1 APOE ε4 allele (2602 Aβ+ [58%] vs 1122 Aβ- [25%]). Aβ+ participants demonstrated worse performance on screening Preclinical Alzheimer Cognitive Composite results and reported higher change scores on the Cognitive Function Index.

Conclusions and Relevance

Among a large group of older individuals screening for an Alzheimer disease (AD) prevention trial, elevated brain amyloid was associated with family history and APOE ε4 allele but not with multiple other previously reported risk factors for AD. Elevated amyloid was associated with lower test performance results and increased reports of subtle recent declines in daily cognitive function. These results support the hypothesis that elevated amyloid represents an early stage in the Alzheimer continuum and demonstrate the feasibility of enrolling these high-risk participants in secondary prevention trials aimed at slowing cognitive decline during the preclinical stages of AD.

Is Reluctance to Share Alzheimer's Disease Biomarker Status with a Study Partner a Barrier to Preclinical Trial Recruitment?

BACKGROUND

Preclinical Alzheimer's disease clinical trials test candidate treatments in individuals with biomarker evidence but no cognitive impairment. Participants are required to co-enroll with a knowledgeable study partner, to whom biomarker information is disclosed.

OBJECTIVE

We investigated whether reluctance to share biomarker results is associated with viewing the study partner requirement as a barrier to preclinical trial enrollment.

DESIGN

We developed a nine-item assessment on views toward the study partner requirement and performed in-person interviews based on a hypothetical clinical trial requiring biomarker testing and disclosure.

SETTING

We conducted interviews on campus at the University of California, Irvine.

PARTICIPANTS

Two hundred cognitively unimpaired older adults recruited from the University of California, Irvine Consent-to-Contact Registry participated in the study.

MEASUREMENTS

We used logistic regression models, adjusting for potential confounders, to examine potential associations with viewing the study partner requirement as a barrier to preclinical trial enrollment.

RESULTS

Eighteen percent of participants reported strong agreement that the study partner requirement was a barrier to enrollment. Ten participants (5%) agreed at any level that they would be reluctant to share their biomarker result with a study partner. The estimated odds of viewing the study partner requirement as a barrier to enrollment were 26 times higher for these participants (OR=26.3, 95% CI 4.0, 172.3), compared to those who strongly disagreed that they would be reluctant to share their biomarker result. Overall, participants more frequently agreed with positive statements than negative statements about the study partner requirement, including 76% indicating they would want their study partner with them when they learned biomarker results.

CONCLUSIONS

This is one of the first studies to explore how potential preclinical Alzheimer's disease trial participants feel about sharing their personal biomarker information with a study partner. Most participants viewed the study partner as an asset to trial enrollment, including having a partner present during biomarker disclosure.

[Early detection of Alzheimer's disease and dementia prediction in patients with mild cognitive impairment : Summary of current recommendations]

Mild cognitive impairment (MCI) is characterized by cognitive deficits but essentially preserved competence in activities of daily living. It is a risk factor for the development of dementia and can reflect a prodromal predementia state of Alzheimer's disease (AD). The pathology of AD is defined by cerebral deposition of amyloid-beta-1-42 protein and aggregation of phosphorylated tau protein, which can be identified in vivo by biomarkers for these alterations. As a result of advances in the field of biomarker-based early detection of AD, it is possible to differentiate between MCI patients with and without a pathological AD condition and therefore, between patients with a low and those with a high risk for the development of dementia. At present there are no specific guideline recommendations in Germany for the diagnostic use of biomarkers in predementia detection of AD and for dementia risk assessment in patients with MCI. This article summarizes the current recommendations of a European expert consensus publication and a multidisciplinary working group of the Alzheimer's Association on the clinical application of cerebrospinal fluid (CSF) biomarkers for the diagnostics of AD in patients with MCI. If the clinical diagnostic criteria for MCI are fulfilled according to the medical history and neuropsychological testing, it is recommended to carry out further diagnostics (blood test, brain imaging) in order to more precisely define the differential diagnostic classification. Counseling on the potential benefits, limits and risks of biomarker testing for early AD detection and dementia risk prediction should always precede assessment of CSF biomarkers. Information about the individual risk of developing dementia has potential consequences for the psychological well-being and life planning; therefore, clinical follow-up visits are recommended.

Use of Cerebrospinal Fluid Biomarkers of Alzheimer's Disease Risk in Mild Cognitive Impairment and Subjective Cognitive Decline in Routine Clinical Care in Germany

BACKGROUND

The National Institute of Aging and Alzheimer's Association's diagnostic recommendations for preclinical Alzheimer's disease (AD) and mild cognitive impairment (MCI) define AD by pathological processes which can be detected by biomarkers. These criteria were established as part of a research framework intended for research purposes but progressively enter the clinical practice.

OBJECTIVE

We investigated the availability, frequency of use, interpretation, and therapeutic implications of biomarkers for the etiologic diagnosis and prognosis in MCI and subjective cognitive decline (SCD) in routine clinical care.

METHODS

We conducted a cross-sectional questionnaire survey among 215 expert dementia centers (hospitals and memory clinics) in Germany.

RESULTS

From the 98 centers (45.6% of contacted centers) included, two-thirds reported use of the cerebrospinal fluid (CSF) biomarkers Aβ42, tau, and phospho-tau in the diagnostic workup of MCI and one third in SCD. CSF biomarker analysis was more often employed by neurological (MCI 84%; SCD 42%) compared to psychiatric institutions (MCI 61%; SCD 33%; p≤0.001). Although dementia experts disagreed on the risk of progression associated with different CSF biomarker constellations, CSF biomarker results guided therapeutic decisions: ∼40% of responders reported to initiate cholinesterase inhibitor therapy in MCI and 18% in SCD (p = 0.006), given that all CSF biomarkers were in the pathological range.

CONCLUSION

Considering the vast heterogeneity among dementia expert centers in use of CSF biomarker analysis, interpretation of results, and therapeutic consequences, a standardization of biomarker-based diagnosis practice in pre-dementia stages is needed.

Towards early disease modification of Parkinson's disease: a review of lessons learned in the Alzheimer field

Parkinson’s disease (PD) research is beginning to focus on early disease modification and prevention. The therapeutic pipeline includes a growing range of pharmacological interventions that could theoretically intervene with the underlying disease process. It is hoped that applying such interventions in a very early stage of the disease pathology, before the onset of motor symptoms or during its early stages, may prevent or delay further disease progression. To identify people in this early disease stage, criteria for ‘prodromal PD’ have been proposed—describing people with one or more specific features that jointly constitute a variably increased risk of developing clinically manifest PD. Here, we aim to draw lessons from the field of Alzheimer’s research, which has followed a similar strategy over the last decade, including the expansion of the disease label to ‘prodromal’ stages. Importantly, none of the large and costly randomized-controlled trials aiming to slow down or prevent Alzheimer’s dementia by targeting the alleged disease pathology, i.e., amyloid-β aggregation, resulted in detectable clinical effects. Lack of sufficiently robust phase 2 trial results before moving to phase 3 studies, suboptimal participant selection, insensitive outcomes, a too narrow target focus, and trial design flaws contributed to this disappointing outcome. We discuss the various similarities between these Alzheimer’s and PD approaches, and review the design of prevention or early disease modification trials for both diseases including the potential for immunotherapy. Finally, we offer considerations to optimize the design of such trials in PD, benefiting from the lessons learned in Alzheimer’s prevention research.

Cognitively unimpaired adults' reactions to disclosure of amyloid PET scan results

IMPORTANCE

Clinical guidelines currently recommend against amyloid imaging for cognitively unimpaired persons. The goal of Alzheimer's disease (AD) prevention, together with advances in understanding the pathophysiology of AD, however, has led to trials testing drugs in cognitively unimpaired persons who show evidence of AD biomarkers. Assuming the eventual success of such trials, millions of patients will be affected. There is a need to understand the effects of biomarker disclosure on those individuals.

DESIGN

The Study of Knowledge and Reactions to Amyloid Testing (SOKRATES) involved 2 semi-structured telephone interviews with individuals who received amyloid PET scan results as part of screening for research participation. Post-disclosure interviews were conducted at 4 to 12 weeks and again 1 year later. Data were collected from November 5, 2014 to November 30, 2016. Interviews were transcribed and coded in NVivo 12.0.

PARTICIPANTS

80 adults aged 65 and older: 50 who received "elevated" and 30 who received "not-elevated" amyloid PET scan results.

MAIN OUTCOMES

Interviews examined four domains: (1) comprehension of the amyloid PET scan result; (2) implications of the result for sense of self, memory, and future; (3) sharing of results with others; and (4) AD risk-reduction behaviors.

RESULTS

Participants who received an elevated amyloid PET scan result viewed the result as more serious and sensitive than other medical test results given its unique implications for identity, self-determination, and stigma. In contrast, participants who received a not-elevated amyloid PET scan result described feeling relief and reinterpreted perceived memory impairments as normal aging. Participants with elevated amyloid reported contemplating and making more changes to health behaviors and future plans than their peers with not-elevated amyloid.

CONCLUSIONS

Clinical practice in the diagnosis and treatment of persons with preclinical AD, a stage of the disease defined by the presence of biomarkers in the absence of cognitive impairment, will need to address matters of identity, stigma, and life-planning.

Alzheimer's Prevention Initiative Generation Program: Development of an APOE genetic counseling and disclosure process in the context of clinical trials

Introduction

As the number of Alzheimer's disease (AD) prevention studies grows, many individuals will need to learn their genetic and/or biomarker risk for the disease to determine trial eligibility. An alternative to traditional models of genetic counseling and disclosure is needed to provide comprehensive standardized counseling and disclosure of apolipoprotein E (APOE) results efficiently, safely, and effectively in the context of AD prevention trials.

Methods

A multidisciplinary Genetic Testing, Counseling, and Disclosure Committee was established and charged with operationalizing the Alzheimer's Prevention Initiative (API) Genetic Counseling and Disclosure Process for use in the API Generation Program trials. The objective was to provide consistent information to research participants before and during the APOE counseling and disclosure session using standardized educational and session materials.

Results

The Genetic Testing, Counseling, and Disclosure Committee created a process consisting of eight components: requirements of APOE testing and reports, psychological readiness assessment, determination of AD risk estimates, guidance for identifying providers of disclosure, predisclosure education, APOE counseling and disclosure session materials, APOE counseling and disclosure session flow, and assessing APOE disclosure impact.

Discussion

The API Genetic Counseling and Disclosure Process provides a framework for large-scale disclosure of APOE genotype results to study participants and serves as a model for disclosure of biomarker results. The process provides education to participants about the meaning and implication(s) of their APOE results while also incorporating a comprehensive assessment of disclosure impact. Data assessing participant safety and psychological well-being before and after APOE disclosure are still being collected and will be presented in a future publication.

•

Participants may need to learn their risk for Alzheimer's disease to enroll in studies.

•

Alternatives to traditional models of apolipoprotein E counseling and disclosure are needed.

•

An alternative process was developed by the Alzheimer's Prevention Initiative.

•

This process has been implemented by the Alzheimer's Prevention Initiative Generation Program.

Comprehension of an Elevated Amyloid Positron Emission Tomography Biomarker Result by Cognitively Normal Older Adults

Importance

The goal of Alzheimer disease (AD) prevention together with advances in understanding the pathophysiology of AD have led to clinical trials testing drugs in cognitively unimpaired persons who show evidence of AD biomarkers. Data are needed to inform the processes of describing AD biomarkers to cognitively normal adults and assessing their understanding of this knowledge.

Objective

To determine the comprehension of an elevated amyloid positron emission tomographic (PET) biomarker result by cognitively unimpaired adults.

Design, Setting, and Participants

The Study of Knowledge and Reactions to Amyloid Testing, a substudy of an AD prevention trial, involved 2 semistructured telephone interviews with 80 participants recruited from 9 study sites: 50 received elevated and 30 received not elevated amyloid PET scan results. Interviews were conducted 4 to 12 weeks after result disclosure and again 1 year later. Data presented here were collected from November 5, 2014, through December 10, 2015. The 50 participants included in this study were cognitively normal, aged 65 to 85 years, evenly distributed by gender, and had elevated amyloid PET results. Subsequent reports will examine persons with "not elevated" results and compare the influence of the different results.

Main Outcomes and Measures

Participant comprehension of an elevated amyloid result was assessed by analyzing their responses to the following questions: "What was the result of your amyloid PET scan?" (followed by "Can you tell me in your own words what that means?" or "How would you explain it to a friend?"), "Was it the result you expected?" and "Did the result teach you anything or clarify anything for you?"

Results

Of the 50 participants aged 65 to 85 years, 49 (98%) were white, 40 (80%) reported a family history of AD, and 30 (60%) had a postgraduate educational level. Most participants (31 [62%]) understood that elevated amyloid conferred an increased but uncertain risk of developing AD. Some desired understanding of the term elevated other than its being a categorical result enabling trial entry eligibility; they wanted information regarding how elevated their amyloid was, how close to the study threshold they were, or percentages, numbers, or a scale to help them make sense of the result.

Conclusions and Relevance

Including an explanation of how and why a dimensional biomarker is converted to a categorical classification would enhance future AD biomarker clinical trials and educational materials.

Incidental findings on brain imaging and blood tests: results from the first phase of Insight 46, a prospective observational substudy of the 1946 British birth cohort

OBJECTIVE

To summarise the incidental findings detected on brain imaging and blood tests during the first wave of data collection for the Insight 46 study.

DESIGN

Prospective observational sub-study of a birth cohort.

SETTING

Single-day assessment at a research centre in London, UK.

PARTICIPANTS

502 individuals were recruited from the MRC National Survey of Health and Development (NSHD), the 1946 British birth cohort, based on pre-specified eligibility criteria; mean age was 70.7 (SD: 0.7) and 49% were female.

OUTCOME MEASURES

Data regarding the number and types of incidental findings were summarised as counts and percentages, and 95% confidence intervals were calculated.

RESULTS

93.8% of participants completed a brain scan (n=471); 4.5% of scanned participants had a pre-defined reportable abnormality on brain MRI (n=21); suspected vascular malformations and suspected intracranial mass lesions were present in 1.9% (n=9) and 1.5% (n=7) respectively; suspected cerebral aneurysms were the single most common vascular abnormality, affecting 1.1% of participants (n=5), and suspected meningiomas were the most common intracranial lesion, affecting 0.6% of participants (n=3); 34.6% of participants had at least one abnormality on clinical blood tests (n=169), but few reached the prespecified threshold for urgent action (n=11).

CONCLUSIONS

In older adults, aged 69-71 years, potentially serious brain MRI findings were detected in around 5% of participants, and clinical blood test abnormalities were present in around one third of participants. Knowledge of the expected prevalence of incidental findings in the general population at this age is useful in both research and clinical settings.

AD molecular: PET amyloid imaging across the Alzheimer's disease spectrum: From disease mechanisms to prevention

The advent of amyloid-beta (Aβ) positron emission tomography (PET) imaging has transformed the field of Alzheimer's disease (AD) by enabling the quantification of cortical Aβ accumulation and propagation in vivo. This revolutionary tool has made it possible to measure direct associations between Aβ and other AD biomarkers, to identify factors that influence Aβ accumulation and to redefine entry criteria into clinical trials as well as measure drug target engagement. This chapter summarizes the main findings on the associations of Aβ with other biomarkers of disease progression across the AD spectrum. It discusses investigations of the timing at which Aβ pathology starts to accumulate, demonstrates the clinical utility of Aβ PET imaging and discusses some ethical implications. Finally, it presents genetic and potentially modifiable lifestyle factors that might influence Aβ accumulation and therefore be targets for AD prevention.

Reactions to learning a "not elevated" amyloid PET result in a preclinical Alzheimer's disease trial

BACKGROUND

The experiences of biomarker-ineligible cognitively normal persons can inform trial conduct and the translation of preclinical Alzheimer's disease (AD) into clinical practice.

METHODS

We interviewed 33 persons whose "not elevated" brain amyloid imaging biomarker result made them ineligible for a preclinical AD trial.

RESULTS

Most participants (n = 17) reported being informed that they did not demonstrate adequately elevated amyloid to qualify, whereas some (n = 14) reported being told they had no amyloid or plaques. Relief (n = 17) and disappointment related to not being able to participate (n = 12) were the most common reactions to results. Nearly all participants would have made healthy lifestyle changes if they had received an "elevated" result, would have another scan, and would participate in another AD prevention trial.

CONCLUSIONS

Although some participants may misconstrue results, disclosure of a "not elevated" amyloid result in the research setting causes little behavior change; willingness to participate in AD research remains.

AMYPAD Diagnostic and Patient Management Study: Rationale and design

INTRODUCTION

Reimbursement of amyloid-positron emission tomography (PET) is lagging due to the lack of definitive evidence on its clinical utility and cost-effectiveness. The Amyloid Imaging to Prevent Alzheimer's Disease-Diagnostic and Patient Management Study (AMYPAD-DPMS) is designed to fill this gap.

METHODS

AMYPAD-DPMS is a phase 4, multicenter, prospective, randomized controlled study. Nine hundred patients with subjective cognitive decline plus, mild cognitive impairment, and dementia possibly due to Alzheimer's disease will be randomized to ARM1, amyloid-PET performed early in the diagnostic workup; ARM2, amyloid-PET performed after 8 months; and ARM3, amyloid-PET performed whenever the physician chooses to do so.

ENDPOINTS

The primary endpoint is the difference between ARM1 and ARM2 in the proportion of patients receiving a very-high-confidence etiologic diagnosis after 3 months. Secondary endpoints address diagnosis and diagnostic confidence, diagnostic/therapeutic management, health economics and patient-related outcomes, and methods for image quantitation.

EXPECTED IMPACTS

AMYPAD-DPMS will supply physicians and health care payers with real-world data to plan management decisions.

Amyloid positron emission tomography candidates may focus more on benefits than risks of results disclosure

Introduction

Given mounting calls to disclose biomarker test results to research participants, we explored factors underlying decisions by patients with mild cognitive impairment to receive amyloid imaging results.

Methods

Prospective, qualitative interviews were conducted with 59 participants (30 = mild cognitive impairment patients, 29 = care partners) from the scan arm of a randomized controlled trial on the effects of amyloid PET results disclosure in an Alzheimer Disease Research Center setting.

Results

Sixty-three percent of the participants were female, with an average age of 72.9 years, and most had greater than a high school level of education (80%). Primary motivations included: (1) better understanding one's mild cognitive impairment etiology and prognosis to plan ahead, and (2) learning one's brain amyloid status for knowledge's sake, regardless of whether the information is actionable. Most participants demonstrated an adequate understanding of the scan's limitations, yet instances of characterizing amyloid PET as a definitive test for Alzheimer's disease occurred. Mention of potential drawbacks, such as negative psychological outcomes, was minimal, even among care partners.

Discussion

Findings demonstrate a risk of disproportionate focus on possible benefits of testing among amyloid scan candidates and suggest a need to clearly emphasize the limitations of amyloid PET when counseling cognitively impaired patients and their families before testing. Future research should examine whether minimizing drawbacks at the pre-imaging stage has adverse consequences on results disclosure.

Disclosure of amyloid positron emission tomography results to individuals without dementia: a systematic review

Background

Disclosure of amyloid positron emission tomography (PET) results to individuals without dementia has become standard practice in secondary prevention trials and also increasingly occurs in clinical practice. However, this is controversial given the current lack of understanding of the predictive value of a PET result at the individual level and absence of disease-modifying treatments. In this study, we systematically reviewed the literature on the disclosure of amyloid PET in cognitively normal (CN) individuals and patients with mild cognitive impairment (MCI) in both research and clinical settings.

Methods

We performed a systematic literature search of four scientific databases. Two independent reviewers screened the identified records and selected relevant articles. Included articles presented either empirical data or theoretical data (i.e. arguments in favor or against amyloid status disclosure). Results from the theoretical data were aggregated and presented per theme.

Results

Of the seventeen included studies, eleven reported empirical data and six provided theoretical arguments. There was a large variation in the design of the empirical studies, which were almost exclusively in the context of cognitively normal trial participants, comprising only two prospective cohort studies quantitatively assessing the psychological impact of PET result disclosure which showed a low risk of psychological harm after disclosure. Four studies showed that both professionals and cognitively normal individuals support amyloid PET result disclosure and underlined the need for clear disclosure protocols. From the articles presenting theoretical data, we identified 51 ‘pro’ and ‘contra’ arguments. Theoretical arguments in favor or against disclosure were quite consistent across population groups and settings. Arguments against disclosure focused on the principle of non-maleficence, whereas its psychological impact and predictive value is unknown. Important arguments in favor of amyloid disclosure are the patients right to know (patient autonomy) and that it enables early future decision making.

Discussion

Before amyloid PET result disclosure in individuals without dementia in a research or clinical setting is ready for widespread application, more research is needed about its psychological impact, and its predictive value at an individual level. Finally, communication materials and strategies to support disclosure of amyloid PET results should be further developed and prospectively evaluated.

Electronic supplementary material

The online version of this article (10.1186/s13195-018-0398-3) contains supplementary material, which is available to authorized users.

Biomarkers and the diagnosis of preclinical dementia

Alzheimer's disease pathology accumulates years before the onset of clinical symptoms and has been termed ‘preclinical dementia’. Biomarkers have been developed to detect this pathology – namely, brain amyloid deposition and markers of neurodegeneration. In this article we describe these biomarkers and review the evidence for their clinical use in predicting risk both in the cognitively ‘normal’ and in those who already have established cognitive decline. We also discuss the limitations and ethical considerations of these tests and consider whether we should start incorporating Alzheimer's disease biomarkers into clinical practice. We find that, because many cognitively healthy people will have Alzheimer's pathology, and it is not clear whether this does help predict future risk of Alzheimer's disease, diagnosing preclinical dementia carries numerous ethical implications and is currently not being advocated outside research settings.

LEARNING OBJECTIVES

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DECLARATION OF INTEREST

J. C. H. works in the Research Institute for the Care of Older People (RICE), which undertakes clinical drug trials for drug companies. He is a sub-investigator on a number of trials (some of which involve neuroimaging and biomarkers) and principal investigator and chief investigator on two trials (neither of which involves biomarkers). All of these trials concern Alzheimer's disease or dementia. He does not receive any direct personal payment from the trials: the payment goes to RICE, which does, however, fund almost half of his post. RICE is an independent charity and separate from the University of Bristol.

At, with and beyond risk: expectations of living with the possibility of future dementia

Biomedical research aimed at the development of therapies for chronic and late-onset conditions increasingly concentrates on the early treatment of symptom-less disease. This broad trend is evidenced in prominent shifts in contemporary dementia research. Revised diagnostic criteria and new approaches to clinical trials propose a focus on earlier stages of disease and prompt concerns about the implications of communicating test results associated with the risk of developing dementia when no effective treatments are available. This article examines expectations of the implications of learning test results related to dementia risk, based on focus group research conducted in the UK and Spain. It points to the extended social and temporal aspects of the dementia risk experience. Three key dimensions of this risk experience are elaborated: living 'at risk', represented in efforts to reduce risk and plan for the future; 'with risk', through vigilance towards cognitive health and earlier or prolonged contact with healthcare services; and finally, 'beyond risk' through a cessation of the self in its current social, legal and financial form. A virtual abstract of this paper can be viewed at: https://www.youtube.com/channel/UC_979cmCmR9rLrKuD7z0ycA.

From information to follow-up: Ethical recommendations to facilitate the disclosure of amyloid PET scan results in a research setting

In the field of Alzheimer's disease research, the use of biomarkers such as amyloid positron emission tomography (PET) has become widespread over a relatively brief period of time. There is an increasing tendency in research studies and trials to switch from no disclosure under any condition toward a qualified disclosure of individual research results, such as amyloid PET scan results. This perspective article aims to evaluate the possible need for a modification of the available recommendations on amyloid PET scan disclosure, based on recent empirical evidence obtained within the field of amyloid PET. This article also applies the International Guideline for Good Clinical Practice to the field of amyloid PET disclosure. Hence, we propose several recommendations to facilitate amyloid PET disclosure while minimizing possible risks of amyloid disclosure in a research context.

Perspectives on Communicating Biomarker-Based Assessments of Alzheimer's Disease to Cognitively Healthy Individuals

In clinical trials which target pathophysiological mechanisms associated with Alzheimer's disease, research participants who are recruited based on biomarker test results should be informed about their increased risk of developing Alzheimer's dementia. This paper presents the results of a qualitative focus group study of attitudes and concerns toward learning information about biomarker-based risk status among healthy research participants in the United Kingdom and Spain and people with dementia and their supporters/caregivers from countries represented in the European Working Group of People with Dementia of Alzheimer Europe. The study identified expectations related to learning risk status and preferences related to the content, quality, and follow-up of the disclosure process. The latter emphasize distinctions between risk and diagnoses, the importance of clear information about risk, and suggestions for risk reduction, as well as expectations for follow up and support. The implications of these preferences for practice are discussed. Providing details of research participants' experience and views may serve as a guide for the development of processes for the responsible disclosure of Alzheimer's disease biomarkers.

Study partners should be required in preclinical Alzheimer's disease trials

Background

In an effort to intervene earlier in Alzheimer’s disease (AD), clinical trials are testing promising candidate therapies in preclinical disease. Preclinical AD trial participants are cognitively normal, functionally independent, and autonomous decision-makers. Yet, like AD dementia trials, preclinical trials require dual enrollment of a participant and a knowledgeable informant, or study partner.

Main text

The requirement of dyadic enrollment is a barrier to recruitment and may present unique ethical challenges. Despite these limitations, the requirement should continue. Study partners may be essential to ensure participant safety and wellbeing, including overcoming distress related to biomarker disclosure and minimizing risk for catastrophic reactions and suicide. The requirement may maximize participant retention and ensure data integrity, including that study partners are the source of data that will ultimately instruct whether a new treatment has a clinical benefit and meaningful impact on the population health burden associated with AD. Finally, study partners are needed to ensure the scientific and clinical value of trials.

Conclusions

Preclinical AD will represent a new model of care, in which persons with no symptoms are informed of probable cognitive decline and eventual dementia. The rationale for early diagnosis in symptomatic AD is equally applicable in preclinical AD—to minimize risk, maximize quality of life, and ensure optimal planning and communication. Family members and other sources of support will likely be essential to the goals of this new model of care for preclinical AD patients and trials must instruct this clinical practice.