To know or not to know: ethical issues related to early diagnosis of Alzheimer's disease

Alzheimer disease blood biomarkers: considerations for population-level use

In the past 5 years, we have witnessed the first approved Alzheimer disease (AD) disease-modifying therapy and the development of blood-based biomarkers (BBMs) to aid the diagnosis of AD. For many reasons, including accessibility, invasiveness and cost, BBMs are more acceptable and feasible for patients than a lumbar puncture (for cerebrospinal fluid collection) or neuroimaging. However, many questions remain regarding how best to utilize BBMs at the population level. In this Review, we outline the factors that warrant consideration for the widespread implementation and interpretation of AD BBMs. To set the scene, we review the current use of biomarkers, including BBMs, in AD. We go on to describe the characteristics of typical patients with cognitive impairment in primary care, who often differ from the patient populations used in AD BBM research studies. We also consider factors that might affect the interpretation of BBM tests, such as comorbidities, sex and race or ethnicity. We conclude by discussing broader issues such as ethics, patient and provider preference, incidental findings and dealing with indeterminate results and imperfect accuracy in implementing BBMs at the population level.

Exploring diagnostic strategies for memory complaints in older adults: A retrospective general practice database study

OBJECTIVES

For older people who worry about their memory, their general practitioner (GP) is often the first healthcare professional they turn to. This study aims to increase knowledge of GPs' daily practice on diagnostic strategies for patients who present themselves with memory complaints and/or worries about dementia for the first time in general practice and to explore associations of patients' characteristics with these strategies.

METHOD

Retrospective observational study using electronic patient records from patients presenting with memory complaints between 2012 and 2019. The patient records are derived from a Dutch primary care registration network. The decision on diagnostic strategy was extracted and categorized as (1) wait and see, (2) diagnostic testing in primary care, or (3) referral. Patient characteristics (gender, age, general practice, level of comorbidities, chronic polypharmacy, and the number of consultations on memory complaints), fear of developing dementia, and information on why the first consultation on memory complaints was scheduled were extracted.

RESULTS

A total of 228 patients were included. Most patients were cared for within primary care, either for further primary care diagnostics (56.1%) or because a wait-and-see strategy was pursued (14.9%). One-third (28.9%) of patients were referred. Differences between diagnostic strategies in patient characteristics, fear of developing dementia, or reason for first consultation between these diagnostic strategies were not found, nor were these variables predictive of referral.

CONCLUSION

Most Dutch patients with memory complaints and/or worries about dementia who seek help from their GP for the first time are cared for in the primary care setting for the following 6 months. The lack of association between included patient characteristics and diagnostic strategies highlights the complexity of the decision-making process on diagnostic testing for dementia in general practice.

REM Sleep Behavior Disorder as a Pathway to Dementia: If, When, How, What, and Why Should Physicians Disclose the Diagnosis and Risk for Dementia

Purpose of Review

People with isolated REM (rapid eye movement) sleep behavior disorder (iRBD) have a high lifetime risk of developing a neurodegenerative disease, including dementia, but disclosure of this risk remains controversial. Herein, we summarize this controversy and provide guidance on disclosure.

Recent Findings

Neurodegeneration risk disclosure in iRBD is controversial because of a long latency to disease onset and a lack of preventative strategies. Balancing the relevant ethical principles of beneficence, nonmaleficence, and autonomy is challenging. Although there are few data on disclosure in iRBD, evidence from discussing risk in other diseases with dementia provides some guidance.

Summary

We provide an approach to risk disclosure for patients with iRBD. Patients should be asked if they want to know about future risks. If so, disclosure should be patient centered, focusing on what might happen. Discussion should occur early to give patients time to prepare for the future and consider participating in research.

Implementation of a diagnostic decision aid for people with memory complaints and their general practitioners: a protocol of a before and after pilot trial

INTRODUCTION

Researchers, policy-makers and healthcare professionals often stress the importance of an early dementia diagnosis. Empirical evidence, however, is scarce leading to a lack of consensus on the necessity of diagnosing dementia early. We emphasise the need for a 'timely' diagnosis, that is, one that occurs at the right moment for a person with memory complaints and his/her significant other. As the optimal timing differs between individuals, the implementation of shared decision making (SDM), preferably by the general practitioner (GP), as the start of a diagnostic trajectory, could help to determine this timely moment. SDM, however, is rarely practised with respect to dementia diagnoses. Therefore, in the context of the Shared Decision-Making regarding Dementia Diagnosis project, a patient decision aid (PtDA) for 'timely' dementia diagnosis in general practice will be developed. This protocol will describe the planned before and after evaluation of its implementation.

METHODS AND ANALYSIS

In a mixed-methods pilot study, we will investigate decision-making processes and experiences regarding a diagnostic trajectory before and after the introduction of a PtDA for people with memory complaints, their significant others and their GPs. The 'before group' will receive diagnostics as usual from their GPs. The 'after group' will use the PtDA. We expect the PtDA to increase the level of SDM and to contribute to a timely and personalised diagnostic trajectory. Data will be collected using semistructured interviews, questionnaires and information retrieved from people with memory complaints' medical records.

ETHICS AND DISSEMINATION

This study protocol was approved by the Medical Review Ethics Committee of the Maastricht University Medical Centre. The findings will be published in peer-reviewed international journals and presented at conferences. This study was funded by the public funded Dutch Research Institute for Care and Medical Sciences (ZonMw).

TRIAL REGISTRATION NUMBER

NCT04531956.

Attitudes towards prediction and early diagnosis of late-onset dementia: a comparison of tested persons and family caregivers

Background: The focus on early detection of dementia and Mild Cognitive Impairment (MCI) diagnosis has entered the clinics' daily routine. However, there exist epistemic uncertainty and moral concerns whether early detection and prediction of dementia is clinically meaningful for the people affected, primarily due to the lack of effective treatment options.Methods: In this study, we adopted qualitative research methods. Twelve face-to-face interviews with tested persons with MCI and early dementia and five focus groups with family caregivers were conducted in Germany in order to explore and analyze their understanding and assessments of early detection and prediction of dementia in memory clinics.Results: Our study revealed that there was much uncertainty among the participants diagnosed with MCI especially when compared to the participants with an early dementia diagnosis. Their uncertainty concerned the meaning of a 'MCI' diagnosis as well as the validity of specific biomarker test results. Moreover, we identified different lines of moral issues for and against the tests among the participants. They include a) inter-familiar conflicts of interest in the initial phase of memory problems, b) the hope for (future) therapy and prevention, c) the desire for easier access to experts in memory clinics, d) advance planning, e) stigmatization, as well as, f) suicide as an option to avoid the future loss of self-determination.Conclusions: Current clinical and communication strategies only partly address the perspectives and needs of the affected. A standardized and ethically reflected procedure of the information provided by professionals before testing and afterwards, during disclosure, seems necessary. Further, longitudinal studies are needed to improve our knowledge about the experiences tested persons and family caregivers have with different levels of stigma.

2020 update on the clinical validity of cerebrospinal fluid amyloid, tau, and phospho-tau as biomarkers for Alzheimer's disease in the context of a structured 5-phase development framework

Purpose

In the last decade, the research community has focused on defining reliable biomarkers for the early detection of Alzheimer’s disease (AD) pathology. In 2017, the Geneva AD Biomarker Roadmap Initiative adapted a framework for the systematic validation of oncological biomarkers to cerebrospinal fluid (CSF) AD biomarkers—encompassing the 42 amino-acid isoform of amyloid-β (Aβ42), phosphorylated-tau (P-tau), and Total-tau (T-tau)—with the aim to accelerate their development and clinical implementation. The aim of this work is to update the current validation status of CSF AD biomarkers based on the Biomarker Roadmap methodology.

Methods

A panel of experts in AD biomarkers convened in November 2019 at a 2-day workshop in Geneva. The level of maturity (fully achieved, partly achieved, preliminary evidence, not achieved, unsuccessful) of CSF AD biomarkers was assessed based on the Biomarker Roadmap methodology before the meeting and presented and discussed during the workshop.

Results

By comparison to the previous 2017 Geneva Roadmap meeting, the primary advances in CSF AD biomarkers have been in the area of a unified protocol for CSF sampling, handling and storage, the introduction of certified reference methods and materials for Aβ42, and the introduction of fully automated assays. Additional advances have occurred in the form of defining thresholds for biomarker positivity and assessing the impact of covariates on their discriminatory ability.

Conclusions

Though much has been achieved for phases one through three, much work remains in phases four (real world performance) and five (assessment of impact/cost). To a large degree, this will depend on the availability of disease-modifying treatments for AD, given these will make accurate and generally available diagnostic tools key to initiate therapy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-021-05258-7.

Ethical Implications of Alzheimer's Disease Prediction in Asymptomatic Individuals through Artificial Intelligence

Biomarker-based predictive tests for subjectively asymptomatic Alzheimer’s disease (AD) are utilized in research today. Novel applications of artificial intelligence (AI) promise to predict the onset of AD several years in advance without determining biomarker thresholds. Until now, little attention has been paid to the new ethical challenges that AI brings to the early diagnosis in asymptomatic individuals, beyond contributing to research purposes, when we still lack adequate treatment. The aim of this paper is to explore the ethical arguments put forward for AI aided AD prediction in subjectively asymptomatic individuals and their ethical implications. The ethical assessment is based on a systematic literature search. Thematic analysis was conducted inductively of 18 included publications. The ethical framework includes the principles of autonomy, beneficence, non-maleficence, and justice. Reasons for offering predictive tests to asymptomatic individuals are the right to know, a positive balance of the risk-benefit assessment, and the opportunity for future planning. Reasons against are the lack of disease modifying treatment, the accuracy and explicability of AI aided prediction, the right not to know, and threats to social rights. We conclude that there are serious ethical concerns in offering early diagnosis to asymptomatic individuals and the issues raised by the application of AI add to the already known issues. Nevertheless, pre-symptomatic testing should only be offered on request to avoid inflicted harm. We recommend developing training for physicians in communicating AI aided prediction.

Primary Prevention of Dementia: An Ethical Review

Dementia poses important medical and societal challenges, and of all health risks people face in life, dementia is one of the most feared. Recent research indicates that up to about 40% of all cases of dementia might be preventable. A series of environmental, social, and medical risk-factors have been identified that should be targeted from midlife onwards when people are still cognitively healthy. At first glance, this seems not merely advisable, but even imperative. However, these new developments trigger a series of new ethical questions and concerns which have hardly been addressed to date. Pro-active ethical reflection, however, is crucial to ensure that the interests and well-being of those affected, ultimately all of us, are adequately respected. This is the goal of the current contribution. Against the background of a concrete case in primary dementia prevention, it provides a systematic overview of the current ethical literature and sketches an ethical research agenda. First, possible benefits of increased well-being must be balanced with the burdens of being engaged in particularly long-term interventions for which it is unclear whether they will ever pay out on a personal level. Second, while knowledge about one's options to maintain brain health might empower people, it might also undermine autonomy, put high social pressure on people, medicalize healthy adults, and stigmatize those who still develop dementia. Third, while synergistic effects might occur, the ideals of dementia prevention might also conflict with other health and non-health related values people hold in life.

European Psychiatric Association policy paper on ethical aspects in communication with patients and their families

BACKGROUND

Establishing a valid communication is not only a basic clinical need to be met but also a relevant ethical commitment.

METHODS

On the basis of the relevant literature, ethical issues arising from specific, important situations in clinical practice were identified.

RESULTS

The main ethical problems regarding communication about the disorder, both in general and in relation to prodromal stages, were described and discussed together with those regarding communication about voluntary and involuntary treatments, "dual roles" enacted in clinical practice, genetic counseling, and end-of-life conditions; on the basis of what emerged, ethically driven indications and suggestions were provided.

CONCLUSIONS

Several situations put the psychiatrist in front of relevant dilemmas and doubts which are no easy to face with; an ethically driven approach based upon the principle of the best interest of patients may support clinicians in their decisions.

Communicating uncertainties when disclosing diagnostic test results for (Alzheimer's) dementia in the memory clinic: The ABIDE project

Background

The development of novel diagnostics enables increasingly earlier diagnosis of Alzheimer's disease (AD). Timely diagnosis may benefit patients by reducing their uncertainty regarding the cause of symptoms, yet does not always provide patients with the desired certainty.

Objective

To examine, using both quantitative and qualitative methods, uncertainty communicated by memory clinic clinicians in post‐diagnostic testing consultations with patients and their caregivers.

Methods

First, we identified all uncertainty expressions of 22 clinicians in audiotaped post‐diagnostic testing consultations with 78 patients. Second, we statistically explored relationships between patient/clinician characteristics and uncertainty expressions. Third, the transcribed uncertainty expressions were qualitatively analysed, determining the topic to which they pertained, their source and initiator/elicitor (clinicians/patients/caregivers).

Results

Within 57/78 (73%) consultations, clinicians expressed in total 115 uncertainties, of which 37% elicited by the patient or caregiver. No apparent relationships were found between patient/clinician characteristics and whether or not, and how often clinicians expressed uncertainty. Uncertainty expressions pertained to ten different topics, most frequently patient's diagnosis and symptom progression. Expressed uncertainty was mostly related to the unpredictability of the future and limits to available knowledge.

Discussion and conclusions

The majority of clinicians openly discussed the limits of scientific knowledge and diagnostic testing with patients and caregivers in the dementia context. Noticeably, clinicians did not discuss uncertainty in about one quarter of consultations. More evidence is needed on the beneficial and/or harmful effects on patients of discussing uncertainty with them. This knowledge can be used to support clinicians to optimally convey uncertainty and facilitate patients' uncertainty management.

General practitioners' attitudes towards early diagnosis of dementia: a cross-sectional survey

BACKGROUND

Dementia is often underdiagnosed in general practice, which may be based on general practitioners' (GPs') knowledge and emotional factors as well as external problems. This study aimed to describe GPs' attitudes toward early diagnosis of dementia.

METHODS

Cross-sectional postal survey in Switzerland in 2017. Members of the Swiss Association of General Practitioners (N = 4460) were asked to participate in the survey. The questionnaire assessed attitudes, enablers and barriers to early dementia diagnosis and post-diagnostic intervention strategies. Exploratory factor analysis and linear regression were used.

RESULTS

The survey response rate was 21%. 85% of GPs agreed with enablers of early dementia recognition (e.g. "Plan for the future, organize support and care", "Minimize the strain and insecurity of patients and their informal family caregivers"). On the other hand, 15% of respondents perceived barriers towards early dementia recognition (e.g. "Time constraints in carrying out the necessary procedures to diagnose dementia"). GPs who were more likely to agree with barriers would less often counsel family members (β = - 0.05, 95% CI = - 0.09 - -0.02) or test fitness to drive (β = - 0.05, 95% CI = - 0.09 - -0.02), and more often choose a watchful waiting strategy (β = 0.05, 95% CI = 0.02-0.09).

CONCLUSIONS

The attitude of the majority of GPs is not characterized by diagnostic and therapeutic nihilism. However, negative attitudes were associated with sub-optimal management after the diagnosis. Thus, health systems are required to critically examine the use of available resources allowing GPs to look after patients and their relatives in a holistic way.

Patient Stakeholder Versus Physician Preferences Regarding Amyloid PET Testing

BACKGROUND

Patient and caregiver perspectives on amyloid positron emission tomography (PET) use are largely unexplored, particularly as compared with clinician views.

METHODS

We surveyed clinicians, patients, caregivers, and dementia advocates on topics relating to an evidence-based guideline on amyloid PET use. Topic importance was rated on a 9-point scale. Patient stakeholder and clinician views were compared using the Mann-Whitney U test.

RESULTS

Patient representatives (n=107) rated all survey topics as equal to or more important than clinicians (n=114) except 1 item discussing potential harms of false-positive diagnoses. Differences between patient representative and clinician populations were greatest when comparing the competing values of false-positive and false-negative diagnoses and the value of testing asymptomatic individuals.

CONCLUSIONS

Patients and caregivers emphasized the importance of having a dementia diagnosis and placed more value on testing and outcomes for asymptomatic populations than clinicians. This underscores the importance of research investigating the effect of amyloid PET results on asymptomatic individuals and the need for amyloid PET ordering and disclosure standards.

Using Cerebrospinal Fluid Biomarker Testing to Target Treatment to Patients with Mild Cognitive Impairment: A Cost-Effectiveness Analysis

OBJECTIVE

Cerebrospinal fluid (CSF) biomarkers are shown to facilitate a risk identification of patients with mild cognitive impairment (MCI) into different risk levels of progression to Alzheimer's disease (AD). Knowing a patient's risk level provides an opportunity for earlier interventions, which could result in potential greater benefits. We assessed the cost effectiveness of the use of CSF biomarkers in MCI patients where the treatment decision was based on patients' risk level.

METHODS

We developed a state-transition model to project lifetime quality-adjusted life-years (QALYs) and costs for a cohort of 65-year-old MCI patients from a US societal perspective. We compared four test-and-treat strategies where the decision to treat was based on a patient's risk level (low, intermediate, high) of progressing to AD with two strategies without testing, one where no patients were treated during the MCI phase and in the other all patients were treated. We performed deterministic and probabilistic sensitivity analyses to evaluate parameter uncertainty.

RESULTS

Testing and treating low-risk MCI patients was the most cost-effective strategy with an incremental cost-effectiveness ratio (ICER) of US$37,700 per QALY. Our results were most sensitive to the level of treatment effectiveness for patients with mild AD and for MCI patients. Moreover, the ICERs for this strategy at the 2.5th and 97.5th percentiles were US$18,900 and US$50,100 per QALY, respectively.

CONCLUSION

Based on the best available evidence regarding the treatment effectiveness for MCI, this study suggests the potential value of performing CSF biomarker testing for early targeted treatments among MCI patients with a narrow range for the ICER.

Review of the Ethical Issues of a Biomarker-Based Diagnoses in the Early Stage of Alzheimer's Disease

BACKGROUND

Today, many healthcare or dementia organizations, clinicians, and companies emphasize the importance of detection of Alzheimer's disease in an early phase. This idea has gained considerable momentum due to the development of biomarkers, the recent FDA and EMA approval of three amyloid tracers, and the failure of a number of recent therapeutic trials conducted in the early dementia phase. On the one hand, an early etiological diagnosis can lead to early and more efficacious intervention. On the other hand, it is questioned how early an etiological diagnosis is beneficial to the patient. Here we consider ethical issues related to the process of biomarker testing and the impact on the diagnostic disclosure to patients with mild cognitive impairment due to prodromal Alzheimer's disease.

METHODS

A systematic review of the theoretical bioethics literature was performed by using electronic databases. The review was limited to articles published in English between 2003 and 2016.

RESULTS

A total of twenty articles were included in our effort to make an analysis of the ethical challenges. One of the biggest challenges was the uncertainty and the predictive value of the biomarker-based diagnosis where patients can be amyloid positive without full certainty whether or when they will develop symptomatic decline due to Alzheimer's disease. Another challenge was the tension between the right to know versus the wish not to know, the limited efficacy of currently available treatment options, and the opportunities and consequences after receiving such an early diagnosis.

CONCLUSION

Based on the results and the additional comments in the discussion, several unanswered questions emerged. Therefore, careful consideration of all these ethical issues is required before the disclosure of a biomarker-based diagnosis to the patient with mild cognitive impairment due to Alzheimer's disease.

A Complex Relationship Between Suicide, Dementia, and Amyloid: A Narrative Review

Background: Suicide rates are high among older adults and many conditions have been related to suicide in this population: chronic illnesses, physical disabilities, cancer, social isolation, mental disorders and neurocognitive disorders.

Objectives: Among neurocognitive disorders, analysis of the relationships between dementia and suicidal behaviors led to conflicting results and some questions are still without answer. Particularly, it is not known whether (i) Alzheimer's disease (AD) increases the risk of suicidal ideation and suicide attempts (SA) or the frequency of death by suicide; (ii) the presence of suicidal ideation or SA in people older than 65 years of age is an early dementia sign; and (iii) amyloid load in frontal areas facilitates SA by modifying the decision-making pathway.

Methods: Therefore, in this narrative review, we searched the PubMed database using the medical subject heading (MeSH) terms (“Suicide” AND “Depression”) OR (“Amyloid” OR “Dementia”) to identify recent (from 2000 to 2017) original studies on the links between suicidal behavior, dementia and brain amyloid load. We also explored the clinical and pathophysiological role of depression in these relationships.

Results and Discussion: The findings from these studies suggest that late stage dementia could protect against suicidal ideation and SA. Conversely, the risk of complete suicide is increased during the early phase of cognitive decline.

Conclusions: Serious cognitive impairment and decline of executive functions could protect against negative thoughts related to cognitive disability awareness and against suicide planning.Several factors, including brain amyloid load, could be involved in the increased suicide rate early after the diagnosis of dementia.

Suicide in older adults: current perspectives

Suicidal behavior in older adults (65 years old and over) is a major public health issue in many countries. Suicide rates increase during the life course and are as high as 48.7/100,000 among older white men in the USA. Specific health conditions and stress factors increase the complexity of the explanatory model for suicide in older adults. A PubMed literature search was performed to identify most recent and representative studies on suicide risk factors in older adults. The aim of our narrative review was to provide a critical evaluation of recent findings concerning specific risk factors for suicidal thoughts and behaviors among older people: psychiatric and neurocognitive disorders, social exclusion, bereavement, cognitive impairment, decision making and cognitive inhibition, physical illnesses, and physical and psychological pain. We also aimed to approach the problem of euthanasia or physician-assisted suicide in older adults. Our main findings emphasize the need to integrate specific stress factors, such as feelings of social disconnectedness, neurocognitive impairment or decision making, as well as chronic physical illnesses and disability in suicide models and in suicide prevention programs in older adults. Furthermore, the chronic care model should be adapted for the treatment of older people with long-term conditions in order to improve the treatment of depressive disorders and the prevention of suicidal thoughts and acts.

Advance directives as a tool to respect patients' values and preferences: discussion on the case of Alzheimer's disease

Background

The proposal of the new criteria for the diagnosis of Alzheimer’s disease (AD) based on biomarker data is making possible a diagnosis of AD at the mild cognitive impairment (MCI) or predementia/prodromal– stage. Given the present lack of effective treatments for AD, the opportunity for the individuals to personally take relevant decisions and plan for their future before and if cognitive deterioration occurs is one the main advantages of an early diagnosis.

Main body

Advance directives are largely seen as an effective tool for planning medical care in the event the subject becomes incompetent. Nevertheless, their value has been questioned with regard to people with dementia by scholars who refer to the arguments of personal identity and of patient’s changing interests before and after the onset of dementia.

In this paper, I discuss the value of advance directives in Alzheimer’s disease and other kind of dementia. Despite critics, I argue that advance directives are especially advisable in dementia and provide reasons in favor of their promotion at an early stage of the disease as a valuable tool to respect patients’ values and preferences on medical treatment, including participation in research and end of life decisions. I mainly support advance directives that include both decisions regarding health care and the appointment of an attorney in fact.

Conclusion

I conclude that patients with AD at a prodromal or early stage should be offered the opportunity to execute an advance directive, and that not to honor a demented individual’s directive would be an unacceptable form of discrimination towards those patients.

Completed suicide in an autopsy-confirmed case of early onset Alzheimer's disease

We report a case of a 57-year-old male with clinically diagnosed and autopsy-confirmed early onset Alzheimer's disease who completed suicide by gunshot wound to the chest. This case has several unique aspects that have not been discussed in previous case reports of completed suicide in Alzheimer's disease. In particular, our patient's death was highly planned with successful compensation for his cognitive deficits. After all firearms had been removed from the home as a safety precaution, he obtained a new weapon, hid it and left himself cues to find and use it. The case is discussed in the context of literature differentiating the neural circuitry propagating impulsive versus planned suicidal acts.

Timely Diagnosis for Alzheimer's Disease: A Literature Review on Benefits and Challenges

Background:

Timely diagnosis of Alzheimer’s disease (AD) refers to a diagnosis at the stage when patients come to the attention of clinicians because of concerns about changes in cognition, behavior, or functioning and can be still free of dementia and functionally independent.

Objectives:

To comprehensively review existing scientific evidence on the benefits and potential challenges of making a timely diagnosis of AD.

Methods:

Relevant studies were identified by searching electronic databases (Medline, Embase) and bibliographies for studies published in English between 1 January 2000 and 2 June 2014 on the consequences of a timely diagnosis of AD.

Results:

Nine studies were identified that investigated the consequences of diagnosing AD at the initial stages; none were specifically focused on prodromal AD. A timely diagnosis potentially offers the opportunities of early intervention, implementation of coordinated care plans, better management of symptoms, patient safety, cost savings, and postponement of institutionalization. Barriers to making a timely diagnosis include stigma, suicide risk, lack of training, diagnostic uncertainty, shortage of specialized diagnostic services, and the reluctance of healthcare providers to make a diagnosis when no effective disease-modifying options are available.

Conclusions:

Despite its potential benefits, few published studies have explored the advantages or risks of a timely diagnosis of AD. In light of the cultural shift toward diagnosis at the initial stage of the disease continuum, when the patient does not yet have dementia, more investigations are needed to evaluate the benefits and address the barriers that may impede making a timely AD diagnosis.

Do You Want to Hear the Bad News? The Value of Diagnostic Tests for Alzheimer's Disease

OBJECTIVE

The diagnosis of Alzheimer's disease (AD) remains difficult. Lack of diagnostic certainty or possible distress related to a positive result from diagnostic testing could limit the application of new testing technologies. The objective of this paper is to quantify respondents' preferences for obtaining AD diagnostic tests and to estimate the perceived value of AD test information.

METHODS

Discrete-choice experiment and contingent-valuation questions were administered to respondents in Germany and the United Kingdom. Choice data were analyzed by using random-parameters logit. A probit model characterized respondents who were not willing to take a test.

RESULTS

Most respondents indicated a positive value for AD diagnostic test information. Respondents who indicated an interest in testing preferred brain imaging without the use of radioactive markers. German respondents had relatively lower money-equivalent values for test features compared with respondents in the United Kingdom.

CONCLUSIONS

Respondents preferred less invasive diagnostic procedures and tests with higher accuracy and expressed a willingness to pay up to €700 to receive a less invasive test with the highest accuracy.

From Cognitive Science to Dementia Assessment

Alzheimer’s disease is a degenerative disease of the brain that impairs mental skills and abilities and undermines independent living. It is estimated to affect over 44 million people worldwide, and 5.3 million people in the United States at an estimated cost of US$226 billion. The numbers of people affected are expected to increase dramatically over the next few decades along with increased life expectancy, and costs are expected to be over US$1 trillion by 2050. There is currently no cure, and accurate diagnosis in primary care is hampered by a lack of widely available, reliable, and specific forms of assessment. Accurate diagnosis is essential to avoid inappropriate and expensive clinical follow-up, to evaluate new treatments when these become available, to avoid underestimating or overestimating prevalence of the disease, and to inform policy priorities on resource allocation for health care and for research. We argue that the cognitive and behavioral sciences offer an important route to developing widely available, inexpensive, reliable, and specific assessment tools for the disease.

Public health guidance to facilitate timely diagnosis of dementia: ALzheimer's COoperative Valuation in Europe recommendations

OBJECTIVE

ALzheimer's COoperative Valuation in Europe (ALCOVE) was a Joint Action co-financed by the European Commission to produce a set of evidence-based recommendations for policymakers on dementia. This paper reports on timely diagnosis.

METHODS

Evidence was reviewed from scientific, policy and qualitative research. An online questionnaire was completed by experts from 24 European Union countries detailing current practice. An iterative process with people with dementia, family carers and professionals was utilised to develop recommendations.

RESULTS

Advances in the technical aspects of diagnosis have changed what is understood by early diagnosis. Although research into preclinical stages is crucial, diagnosing at these very earliest stages is not recommended as regular practice. On balance, it is suggested that citizens should have access to accurate diagnosis at a time in the disease process when it can be of most benefit to them. The term timely diagnosis is used to reflect this. The diagnosis can help citizens and their families make sense of what is happening and make lifestyle changes and plans for the future. The central principles identified to maximise benefit and to reduce harm associated with diagnosis at an earlier stage included reducing stigma about dementia; respecting the rights of the individual; recognising that how the diagnosis is given will impact on subsequent adjustment and that post diagnostic support are required for the person and their family. Detailed recommendations are provided for timely detection, the diagnostic process, complex diagnoses, response to early cognitive changes and workforce.

CONCLUSIONS

The recommendations can be utilised at a local, national and European level to benchmark progress.

Clinical utility of cerebrospinal fluid biomarkers in the diagnosis of early Alzheimer's disease

Several potential disease-modifying drugs for Alzheimer's disease (AD) have failed to show any effect on disease progression in clinical trials, conceivably because the AD subjects are already too advanced to derive clinical benefit from treatment and because diagnosis based on clinical criteria alone introduces a high misdiagnosis rate. Thus, well-validated biomarkers for early detection and accurate diagnosis are crucial. Low cerebrospinal fluid (CSF) concentrations of the amyloid-β (Aβ1-42) peptide, in combination with high total tau and phosphorylated tau, are sensitive and specific biomarkers highly predictive of progression to AD dementia in patients with mild cognitive impairment. However, interlaboratory variations in the results seen with currently available immunoassays are of concern. Recent worldwide standardization efforts and quality control programs include standard operating procedures for both preanalytical (e.g., lumbar puncture and sample handling) and analytical (e.g., preparation of calibration curve) procedures. Efforts are also ongoing to develop highly reproducible assays on fully automated instruments. These global standardization and harmonization measures will provide the basis for the generalized international application of CSF biomarkers for both clinical trials and routine clinical diagnosis of AD.

Mild cognitive impairment: safe to drive?

Driving is an important aspect of daily living and for many older people provides autonomy and psycho-social benefits. Cognitive impairment has been found to impact driving skills at the level of dementia, however, uncertainty remains around the impact of a diagnosis of the pre-dementia condition mild cognitive impairment. Current official guidelines are unclear, and assessment of fitness to drive can be problematical. This editorial examines current official guidance available to the clinician and problems with existing assessment as well as the current position of research specifically into MCI and driving, and considers future direction for research in this field.

A methodological critique of the National Institute of Aging and Alzheimer's Association Guidelines for Alzheimer's disease, dementia, and mild cognitive impairments

In 2011, the U.S. National Institute on Aging published guidelines for clinical diagnostics for Alzheimer's disease dementia. These guidelines define a continuum with three stages-an early, pre-clinical stage with no symptoms, followed by mild cognitive impairment, and a final stage of Alzheimer's disease dementia. This methodological critique examines the validity of this continuum. No studies exist showing the progression of these biomarkers to Alzheimer's disease. There is also a lack of empirical evidence showing how biomarkers determine mild cognitive impairment, which has multiple etiologies. The guidelines fail to explain anomalies where there are biomarkers but no expression of Alzheimer's disease.

Patient and carer views on participating in clinical trials for prodromal Alzheimer's disease and mild cognitive impairment

OBJECTIVE

There is great interest in conducting clinical trials of disease-modifying therapies in the prodromal (early, pre-dementia), asymptomatic stages of Alzheimer's disease. Diagnostic biomarker tests offer a means of identifying prodromal patients, but it is unclear how potential participants feel about their use. Deciding whether to take part in a clinical trial is a complex process in which eligible participants must balance risks and discomforts against uncertain benefits. We sought to explore the views of potential participants through qualitative research methods.

METHODS

Focus groups with people with early memory problems, current and former family carers explored attitudes towards participating in clinical trials in the prodromal stages of the disease, using an example of anti-amyloid antibody-therapy (immunotherapy), which are currently in development.

RESULTS

Despite the complexities involved, almost all participants had a clear idea about whether they, personally, would like to take part. Many were highly motivated to obtain an unambiguous diagnosis, regardless of their desire to participate in a clinical trial. Participants expressed minimal concern regarding the risk of adverse events associated with immunotherapy, whereas certain tests and trial procedures provoked greater anxiety. People with memory problems were found to assess the study demands in relation to their own priorities and circumstances.

CONCLUSIONS

The priorities of patients might be different to clinicians and those who design and regulate clinical trials. Patient views can be used to inform the ethical debate around the disclosure of biomarker status, the design of clinical trials and the content of trial information.

Decision-making in older people with dementia

Dementia is a syndrome characterized by a progressive impairment in cognition, function and behaviour, with a considerable burden in terms of health and social care, and economic costs. As Alzheimer's disease and other dementias advance, the patient's capacity, competence and possibility of participation in decision-making decrease. Key points in managing people with dementia include screening of cognitive impairment, neuropsychological assessment, laboratory tests and neuroimaging, genetic tests, informed consent, inclusion in clinical trials and discussion of advance directives, driving, managing finances and testamentary capacity, pharmolocogical and non-pharmacological treatment and also palliative and end-of-life care. In this article we review these crucial points in decision-making for people with dementia and their families and caregivers.

Diagnosis and management of Alzheimer's disease: past, present and future ethical issues

There is great interest in the ethical issues associated with Alzheimer's disease (AD) and related dementias given the prevalence of AD and the evolving neuroscience landscape in matters of diagnoses and therapeutics. Much of the ethics discussion arises in the tension between the principle of not doing harm (principle of non-maleficence) in this vulnerable population and the development of effective treatments (principle of beneficence). Autonomy and capacity issues are also numerous, wide-ranging, and concern (1) day to day affairs such as driving safely and spending money wisely, (2) life-time events such as designating a legal representative in case of incapacity, making a will, (3) consenting to treatment and diagnostic procedures, (4) participating in research. The latter issue is particularly thorny and illustrates well the complexity of tackling concerns related to capacity. The impetus to protect AD patients has partly led to ethics regulation and policies making research on inapt patients more difficult because of stringent requirements for signed informed consent or for showing the value of the research to this specific patient population. New issues are arising that relate to earlier diagnosis using biomarkers and (possibly soon) the use of drugs that modify disease progression. We here summarize and discuss the different ethical issues associated with AD from a historical perspective, with emphasis on diagnostic and treatments issues.

Amyloid imaging in cognitively normal individuals, at-risk populations and preclinical Alzheimer's disease

Recent developments of PET amyloid ligands have made it possible to visualize the presence of Aβ deposition in the brain of living participants and to assess the consequences especially in individuals with no objective sign of cognitive deficits. The present review will focus on amyloid imaging in cognitively normal elderly, asymptomatic at-risk populations, and individuals with subjective cognitive decline. It will cover the prevalence of amyloid-positive cases amongst cognitively normal elderly, the influence of risk factors for AD, the relationships to cognition, atrophy and prognosis, longitudinal amyloid imaging and ethical aspects related to amyloid imaging in cognitively normal individuals. Almost ten years of research have led to a few consensual and relatively consistent findings: some cognitively normal elderly have Aβ deposition in their brain, the prevalence of amyloid-positive cases increases in at-risk populations, the prognosis for these individuals is worse than for those with no Aβ deposition, and significant increase in Aβ deposition over time is detectable in cognitively normal elderly. More inconsistent findings are still under debate; these include the relationship between Aβ deposition and cognition and brain volume, the sequence and cause-to-effect relations between the different AD biomarkers, and the individual outcome associated with an amyloid positive versus negative scan. Preclinical amyloid imaging also raises important ethical issues. While amyloid imaging is definitely useful to understand the role of Aβ in early stages, to define at-risk populations for research or for clinical trial, and to assess the effects of anti-amyloid treatments, we are not ready yet to translate research results into clinical practice and policy. More researches are needed to determine which information to disclose from an individual amyloid imaging scan, the way of disclosing such information and the impact on individuals and on society.

Attitudes of the German general population toward early diagnosis of dementia--results of a representative telephone survey

Background

Early detection of dementia has clearly improved. Even though none of the currently available treatments for the most common form of dementia, Alzheimer’s dementia, promises a cure, early diagnosis provides several benefits for patients, caregivers, and health care systems. This study aimed to describe attitudes toward early diagnosis of dementia in the German general population.

Methods

A representative telephone survey of the German population aged 18+ years (n = 1,002) was conducted in 2011.

Results

The majority of respondents (69%) would be willing to be examined for early diagnosis of dementia. Almost two thirds reported that they would prefer their general practitioner (GP) as the first source of professional help. More than half of the respondents (55%) stated their belief that dementia could be prevented. Respondents mostly indicated psychosocial prevention options.

Conclusions

Our findings suggest that the general population in Germany is very open to early diagnosis of dementia; however, this seems connected with large expectations on the effectiveness of prevention options. Dementia awareness campaigns may be employed to carefully inform the public about the prevention options currently available and their efficacy. To exploit GPs’ potential as a gatekeeper for early detection of dementia, their ability to identify patients with antecedent and mild stages of the disease must be improved.

Neurochemical biomarkers in Alzheimer's disease and related disorders

Neurochemical biomarkers for diagnosing dementias are currently under intensive investigation and the field is rapidly expanding. The main protagonists and the best defined among them are cerebrospinal fluid levels of Aβ42, tau and its phosphorylated forms (p-tau). In addition, novel cerebrospinal fluid biomarkers are emerging and their multiparametric assessment seems most promising for increasing the accuracy in neurochemical dementia diagnostics. The combined assessment of Aβ42 and p-tau has recently shown value for diagnosing prodromal states of Alzheimer's dementia, that is, mild cognitive impairment. Disease-specific biomarkers for other degenerative dementias are still missing, but some progress has recently been made. As lumbar puncture is an additional burden for the patient, blood-based neurochemical biomarkers are definitely warranted and promising new discoveries have been made in this direction. These diagnostic developments have implicit therapeutic consequences and give rise to new requirements for future neurochemical dementia diagnostics.

Disclosure of individualized research results: a precautionary approach

Assessing and managing risks to participants is a central point of contention in the debate about disclosing individualized research results. Those who favor disclosure of only clinically significant results think that disclosing clinically insignificant results is risky and costly, and that harm prevention should take precedence over other ethical considerations. Those who favor giving participants the option of full disclosure regard these risks as insubstantial, and think that obligations to benefit participants and promote their autonomy and right to know outweigh the obligation to prevent harm or financial considerations. The risks of disclosing clinically insignificant research results are currently not quantifiable, due to lack of empirical data. The precautionary principle provides some insight into this debate because it applies to decision-making concerning risks that are plausible but not quantifiable. A precautionary approach would favor full disclosure of individualized results with appropriate safeguards to prevent, minimize, or mitigate risks to participants, such as: validating testing methods; informing participants about their options for receiving tests results and the potential benefits and risks related to receiving results; assessing participants' comfort with handling uncertainty; providing counseling and advice to participants; following-up with individuals who receive tests results; and forming community advisory boards to help investigators deal with issues related to disclosure.