Genetic counseling and testing for Alzheimer disease: joint practice guidelines of the American College of Medical Genetics and the National Society of Genetic Counselors

Updates in Alzheimer's disease: from basic research to diagnosis and therapies

Alzheimer's disease (AD) is the most common neurodegenerative disorder, characterized pathologically by extracellular deposition of β-amyloid (Aβ) into senile plaques and intracellular accumulation of hyperphosphorylated tau (pTau) as neurofibrillary tangles. Clinically, AD patients show memory deterioration with varying cognitive dysfunctions. The exact molecular mechanisms underlying AD are still not fully understood, and there are no efficient drugs to stop or reverse the disease progression. In this review, we first provide an update on how the risk factors, including APOE variants, infections and inflammation, contribute to AD; how Aβ and tau become abnormally accumulated and how this accumulation plays a role in AD neurodegeneration. Then we summarize the commonly used experimental models, diagnostic and prediction strategies, and advances in periphery biomarkers from high-risk populations for AD. Finally, we introduce current status of development of disease-modifying drugs, including the newly officially approved Aβ vaccines, as well as novel and promising strategies to target the abnormal pTau. Together, this paper was aimed to update AD research progress from fundamental mechanisms to the clinical diagnosis and therapies.

The yield of genetic workup for middle-aged and elderly patients with neurological disorders in a real-world setting

Genetic workup is becoming increasingly common in the clinical assessment of neurological disorders. We evaluated its yield among middle-aged and elderly neurological patients, in a real-world context. This retrospective study included 368 consecutive Israeli patients aged 50 years and older (202 [54.9%] males), who were referred to a single neurogenetics clinic between 2017 and mid-2023. All had neurological disorders, without a previous molecular diagnosis. Demographic, clinical and genetic data were collected from medical records. The mean age at first genetic counseling at the clinic was 62.3 ± 7.8 years (range 50-85 years), and the main indications for referral were neuromuscular, movement and cerebrovascular disorders, as well as cognitive impairment and dementia. Out of the 368 patients, 245 (66.6%) underwent genetic testing that included exome sequencing (ES), analysis of nucleotide repeat expansions, detection of specific mutations, targeted gene panel sequencing or chromosomal microarray analysis. Overall, 80 patients (21.7%) received a molecular diagnosis due to 36 conditions, accounting for 32.7% of the patients who performed genetic testing. The diagnostic rates were highest for neuromuscular (58/186 patients [31.2%] in this group, 39.2% of 148 tested individuals) and movement disorders (14/79 [17.7%] patients, 29.2% of 48 tested), but lower for other disorders. Testing of nucleotide repeat expansions and ES provided a diagnosis to 28/73 (38.4%) and 19/132 (14.4%) individuals, respectively. Based on our findings, genetic workup and testing are useful in the diagnostic process of neurological patients aged ≥50 years, in particular for those with neuromuscular and movement disorders.

Expanded genetic testing in familial hypercholesterolemia-A single center's experience

Objective

Assess the yield of genetic testing for pathogenic variants in ABCG5, ABCG8, LIPA, and APOE in individuals with personal and family histories suggestive of familial hypercholesterolemia.

Methods

Retrospective review of patients seen in the Advanced Lipid Disorders Clinic at Johns Hopkins.

Results

In the lipid clinic at a single center during the years 2015-2023, 607 patients underwent genetic testing for familial hypercholesterolemia, of which 263 underwent the expanded genetic testing for sitosterolemia. Eighty-eight patients had genetic testing which included APOE, and 22 patients had testing which included LIPA. Among these, one patient was identified to have a pathogenic variant in APOE and another patient with a pathogenic variant in ABCG5 (0.7 % yield). The frequency of a positive result was double that of a variant of uncertain significance.

Conclusion

These data suggest in rare cases expanded testing can provide answers for patients and families with a minimal likelihood of a variant of uncertain significance.

2024 Alzheimer's disease facts and figures

This article describes the public health impact of Alzheimer's disease (AD), including prevalence and incidence, mortality and morbidity, use and costs of care and the ramifications of AD for family caregivers, the dementia workforce and society. The Special Report discusses the larger health care system for older adults with cognitive issues, focusing on the role of caregivers and non-physician health care professionals. An estimated 6.9 million Americans age 65 and older are living with Alzheimer's dementia today. This number could grow to 13.8 million by 2060, barring the development of medical breakthroughs to prevent or cure AD. Official AD death certificates recorded 119,399 deaths from AD in 2021. In 2020 and 2021, when COVID-19 entered the ranks of the top ten causes of death, Alzheimer's was the seventh-leading cause of death in the United States. Official counts for more recent years are still being compiled. Alzheimer's remains the fifth-leading cause of death among Americans age 65 and older. Between 2000 and 2021, deaths from stroke, heart disease and HIV decreased, whereas reported deaths from AD increased more than 140%. More than 11 million family members and other unpaid caregivers provided an estimated 18.4 billion hours of care to people with Alzheimer's or other dementias in 2023. These figures reflect a decline in the number of caregivers compared with a decade earlier, as well as an increase in the amount of care provided by each remaining caregiver. Unpaid dementia caregiving was valued at $346.6 billion in 2023. Its costs, however, extend to unpaid caregivers' increased risk for emotional distress and negative mental and physical health outcomes. Members of the paid health care and broader community-based workforce are involved in diagnosing, treating and caring for people with dementia. However, the United States faces growing shortages across different segments of the dementia care workforce due to a combination of factors, including the absolute increase in the number of people living with dementia. Therefore, targeted programs and care delivery models will be needed to attract, better train and effectively deploy health care and community-based workers to provide dementia care. Average per-person Medicare payments for services to beneficiaries age 65 and older with AD or other dementias are almost three times as great as payments for beneficiaries without these conditions, and Medicaid payments are more than 22 times as great. Total payments in 2024 for health care, long-term care and hospice services for people age 65 and older with dementia are estimated to be $360 billion. The Special Report investigates how caregivers of older adults with cognitive issues interact with the health care system and examines the role non-physician health care professionals play in facilitating clinical care and access to community-based services and supports. It includes surveys of caregivers and health care workers, focusing on their experiences, challenges, awareness and perceptions of dementia care navigation.

Apolipoprotein E Genetic Testing in a New Age of Alzheimer Disease Clinical Practice

The recent FDA approval of amyloid-lowering drugs is changing the landscape of Alzheimer disease (AD) clinical practice. Previously, apolipoprotein E (APOE) genetic testing was not recommended in the care of people with AD because of limited clinical utility. With the advent of amyloid-lowering drugs, APOE genotype will play an important role in guiding treatment recommendations. Recent clinical trials have reported strong associations between APOE genotype and the safety and possibly the efficacy of amyloid-lowering drugs. Therefore, a clinical workflow that includes biomarker and genetic testing should be implemented to provide patients with the opportunity to make informed decisions and instruct safety monitoring for clinicians. Pretest consent, education, and counseling will be an essential aspect of this process for patients and their family members to understand the implications of these tests and their results. Given that the approved amyloid-lowering drugs are indicated for patients with mild cognitive impairment or mild dementia with biomarker evidence of AD, biomarker testing should be performed before genetic testing and genetic testing should only be performed in patients interested in treatment with amyloid-lowering drugs. It is also important to consider other implications of genetic testing, including burden on and need for additional training for clinicians, the role of additional providers, and the potential challenges for patients and families.

Atypical Neuropsychiatric Presentation of FTD-ALS Caused by a Pathogenic Repeat Expansion in C9orf72: A Case Report

The case report describes the presentation of a 42-year-old male ultimately diagnosed with FTD-ALS caused by a genetic mutation, who initially presented with atypical psychiatric symptoms. Given that the initial clinical manifestations of FTD-ALS can be quite variable, the diagnosis is often challenging; the case report aims to highlight several key considerations in the diagnostic assessment, including genetic testing in order to guide clinicians in more timely diagnosis and ultimately improve patient care.

Superoxide dismutase: a key target for the neuroprotective effects of curcumin

Over the past few years, the prevalence of neurodegenerative diseases (NDD) has increased dramatically. The community health system is burdened by the high healthcare costs associated with NDD. Superoxide dismutase (SOD) is a type of metalloenzyme that possesses a distinct characteristic of protecting the body from oxidative stress through antioxidants. In this way, SOD supplementation may activate the endogenous antioxidant mechanism in various pathological conditions and could be used to neutralize free radical excess. Several factors are responsible for damaging DNA and RNA in the body, including the overproduction of reactive species, particularly reactive oxygen species (ROS) and reactive nitrogen species (RNS). Excessive ROS/RNS have deleterious effects on mitochondria and their metabolic processes, mainly through increased mitochondrial proteins, lipids and DNA oxidation. Studies have shown that oxidative stress is implicated in the etiology of many diseases, including NDD. It is thought that anti-inflammatory compounds, particularly phytochemicals, can interfere with these pathways and regulate inflammation. Extensive experimental and clinical research has proven that curcumin (Cur) has anti-inflammatory and anti-neurologic properties. In this review, we have compiled the available data on Cur's anti-inflammatory properties, paying special attention to its therapeutic impact on NDD through SOD.

Genetic testing in adults with neurologic disorders: indications, approach, and clinical impacts

The role of genetic testing in neurologic clinical practice has increased dramatically in recent years, driven by research on genetic causes of neurologic disease and increased availability of genetic sequencing technology. Genetic testing is now indicated for adults with a wide range of common neurologic conditions. The potential clinical impacts of a genetic diagnosis are also rapidly expanding, with a growing list of gene-specific treatments and clinical trials, in addition to important implications for prognosis, surveillance, family planning, and diagnostic closure. The goals of this review are to provide practical guidance for clinicians about the role of genetics in their practice and to provide the neuroscience research community with a broad survey of current progress in this field. We aim to answer three questions for the neurologist in practice: Which of my patients need genetic testing? What testing should I order? And how will genetic testing help my patient? We focus on common neurologic disorders and presentations to the neurology clinic. For each condition, we review the most current guidelines and evidence regarding indications for genetic testing, expected diagnostic yield, and recommended testing approach. We also focus on clinical impacts of genetic diagnoses, highlighting a number of gene-specific therapies recently approved for clinical use, and a rapidly expanding landscape of gene-specific clinical trials, many using novel nucleotide-based therapeutic modalities like antisense oligonucleotides and gene transfer. We anticipate that more widespread use of genetic testing will help advance therapeutic development and improve the care, and outcomes, of patients with neurologic conditions.

Deregulation of the Glymphatic System in Alzheimer's Disease: Genetic and Non-Genetic Factors

Alzheimer's disease (AD) is the most prevalent form of dementia and is characterized by progressive degeneration of brain function. AD gradually affects the parts of the brain that control thoughts, language, behavior and mental function, severely impacting a person's ability to carry out daily activities and ultimately leading to death. The accumulation of extracellular amyloid-β peptide (Aβ) and the aggregation of intracellular hyperphosphorylated tau are the two key pathological hallmarks of AD. AD is a complex condition that involves both non-genetic risk factors (35%) and genetic risk factors (58-79%). The glymphatic system plays an essential role in clearing metabolic waste, transporting tissue fluid, and participating in the immune response. Both non-genetic and genetic risk factors affect the glymphatic system to varying degrees. The main purpose of this review is to summarize the underlying mechanisms involved in the deregulation of the glymphatic system during the progression of AD, especially concerning the diverse contributions of non-genetic and genetic risk factors. In the future, new targets and interventions that modulate these interrelated mechanisms will be beneficial for the prevention and treatment of AD.

Interest in and Experience with Genetic Testing for Late-Onset Medical Conditions: Results from the National Poll on Healthy Aging

BACKGROUND

The increasing availability of genetic testing for late-onset diseases such as Alzheimer's disease necessitates understanding public perceptions and experiences of such testing among at-risk populations.

OBJECTIVES

To assess (a) prior uptake of genetic testing (both in medical and direct-to-consumer settings), (b) future interest in genetic testing for late-onset conditions (e.g., Alzheimer's disease, Parkinson's disease), and (c) perceptions of testing pros and cons among middle-to-older aged adults.

DESIGN

Online, cross-sectional survey study.

SETTING

The National Poll on Healthy Aging at the University of Michigan is a recurring biannual survey of a nationally representative sample of adults aged 50-80. This study reports on a March 2018 fielding of the survey that included a genetic testing module administered to adults aged 50-64.

PARTICIPANTS

Study participants were 991 community-dwelling adults aged 50-64.

MEASUREMENTS

Survey measures assessed (a) prior use of genetic testing, (b) reasons for engaging in genetic testing, (c) interest in different types of genetic testing, including for Alzheimer's disease, Parkinson's disease, and macular degeneration, and (d) perceived benefits, risks, and limitations of testing.

RESULTS

Previous uptake of genetic testing was limited (medical use: 5.1%; direct-to-consumer: 10.8%), with direct-to-consumer test uptake higher among respondents with household incomes of $100,000 or more. Over half of adults endorsed interest in genetic testing for estimation of disease risk (58.9%), ancestry knowledge (58%), and informing medical care (53.8%). Interest in genetic testing for specific late-onset conditions was even higher, including Alzheimer's disease (70%), Parkinson's disease (65.3%), and macular degeneration (64.3%). Multivariable logistic regression models showed that older adults more likely to be interested in genetic testing for medical or disease risk purposes were those with higher levels of education (college degree or higher) and who endorsed the benefits of genetic testing, whereas respondents who endorsed testing risks and limitations were less likely to express interest.

CONCLUSION

While prior use of genetic testing among the middle-to-older age population was low, interest in testing for Alzheimer's disease and other late-onset conditions was high. This high interest may translate into increased uptake given expanded access to testing and recent treatment advances for Alzheimer's disease.

Validation of the "Perceptions Regarding pRE-Symptomatic Alzheimer's Disease Screening" (PRE-ADS) Questionnaire in the German Population: Attitudes, Motivations, and Barriers to Pre-Symptomatic Dementia Screening

BACKGROUND

Attitudes, motivations, and barriers to pre-symptomatic screening for Alzheimer's disease (AD) in the general population are unclear, and validated measurement tools are lacking.

OBJECTIVE

Translation and validation of the German version of the "Perceptions regarding pRE-symptomatic Alzheimer's Disease Screening" (PRE-ADS) questionnaire.

METHODS

A convenience sample (N = 256) was recruited via an online platform. Validation of the PRE-ADS-D consisted of assessments of reliability, structural validity using Principal Component Analysis (PCA) and Exploratory Factor Analysis (EFA) and construct validity using known-group tests. A subscale "Acceptability of Screening", with 5 PRE-ADS-D items, was extracted to measure acceptance of screening in clinical practice. The STROBE checklist was used for reporting.

RESULTS

EFA revealed a three-factor model for the PRE-ADS-D. Acceptable to good internal consistency was found for the 25-item scale (α= 0.78), as well as for the three factors "Concerns about Screening" (α= 0.85), "Intention to be Screened" (α= 0.87), and "Preventive Health Behaviors" (α= 0.81). Construct validity was confirmed for both the 25-item PRE-ADS-D and the "Acceptability of Screening" scale (α= 0.91). Overall, 51.2% of the participants showed a preference for screening. Non-parametric tests were conducted to further explore group differences of the sample.

CONCLUSIONS

The PRE-ADS-D is a reliable and valid tool to measure attitudes, motives, and barriers regarding pre-symptomatic dementia screening in the German-speaking general population. Additionally, the subscale "Acceptability of Screening" demonstrated good construct validity and reliability, suggesting its promising potential as a practical tool in clinical practice.

Public perspective on medications to delay Alzheimer's disease symptoms

Disease-modifying treatments for Alzheimer's disease are emerging. Our research examined how personal risk for AD may influence intentions to ask for medications to delay symptoms of AD, and how the availability of such medications impacts interest in AD-related genetic testing. Invitations to a web-based survey were posted on social media sites. Respondents were sequentially assigned to imagine that they had a 5%, 15%, or 35% chance of developing AD. They were then provided a hypothetical scenario describing a medication that delayed AD symptoms. After reporting intentions to ask for the medication, respondents were asked about their interest in genetic testing to predict AD risk. Data from 310 individuals were analyzed. Intentions to ask for a preventative medication were greater for respondents presented AD risks of 35% compared to risks of 15% and 5% (86% vs. 66% vs. 62%, respectively, p < 0.001). The proportion who would ask for genetic susceptibility testing increased from 58% to 79% when respondents were told to imagine that a medication that delayed AD symptoms existed (p < 0.001). Findings suggest that individuals who know they have an increased risk for AD are more likely pursue medications to delay onset of disease symptoms, and the availability of AD-delaying treatments will increase interest in associated genetic testing. Findings provide insight about who will pursue emerging preventative medications, including individuals for whom the medications may be inappropriate, and the impact on genetic test utilization.

Genetic Phenotypes of Alzheimer's Disease: Mechanisms and Potential Therapy

Years of intensive research has brought us extensive knowledge on the genetic and molecular factors involved in Alzheimer's disease (AD). In addition to the mutations in the three main causative genes of familial AD (FAD) including presenilins and amyloid precursor protein genes, studies have identified several genes as the most plausible genes for the onset and progression of FAD, such as triggering receptor expressed on myeloid cells 2, sortilin-related receptor 1, and adenosine triphosphate-binding cassette transporter subfamily A member 7. The apolipoprotein E ε4 allele is reported to be the strongest genetic risk factor for sporadic AD (SAD), and it also plays an important role in FAD. Here, we reviewed recent developments in genetic and molecular studies that contributed to the understanding of the genetic phenotypes of FAD and compared them with SAD. We further reviewed the advancements in AD gene therapy and discussed the future perspectives based on the genetic phenotypes.

Refining Risk for Alzheimer's Disease Among Heterozygous APOEɛ4 Carriers

In a large population-based cohort, we show not all heterozygous APOEɛ4 carriers are at increased risk for Alzheimer's disease (AD); a significantly higher AD proportion was only found for ɛ3/ɛ4, not ɛ2/ɛ4. Among ɛ3/ɛ4 carriers (24% in the cohort), the AD proportion differed considerably by polygenic risk score (PRS). In particular, the AD proportion was lower than the entire cohort for subjects in the bottom 20-percentile PRS and was higher than that of homozygous ɛ4 carriers for subjects at the top 5th-percentile PRS. Family history was no longer a significant predictor of AD risk after adjusting APOE and PRS.

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.

Family Communication about Diagnostic Genetic Testing for Younger-Onset Dementia

Younger-onset dementia (YOD) refers to onset before 65 years of age and may be associated with a genetic cause. Family communication surrounding any genetic risk is complex, and this process may be further complicated in a YOD context due to its effects on cognition, behaviour, and associated psychosocial consequences. This study aimed to investigate how individuals experience family communication about potential genetic risk and testing for YOD. Thematic analysis was performed on verbatim transcripts of nine semi-structured interviews undertaken with family members who attended a neurogenetics clinic due to a relative diagnosed with YOD. The interviews explored the participants’ experiences of learning that YOD might be inherited and the ensuing family communication about genetic testing. Four key themes emerged: (1) a clinical diagnostic odyssey was common and could be a motivator for genomic testing, (2) pre-existing family tension and/or disconnection was a common barrier, (3) family members’ autonomy was considered, and (4) avoidant coping strategies influenced communication. Communication regarding potential YOD genetic risk is a complicated process and may be influenced by pre-existing family dynamics, individual coping mechanisms, and a desire to promote autonomy in relatives. To promote effective risk communication, genetic counsellors should pre-emptively address family tensions that may be exacerbated in the context of genetic testing for YOD, with awareness that family strain during a preceding period of diagnostic odyssey is common. Genetic counsellors can offer psychosocial support to facilitate coping with this tension in an adaptive way. The findings also indicated the importance of extending genetic counselling support to relatives.

2023 Alzheimer's disease facts and figures

This article describes the public health impact of Alzheimer's disease, including prevalence and incidence, mortality and morbidity, use and costs of care, and the overall impact on family caregivers, the dementia workforce and society. The Special Report examines the patient journey from awareness of cognitive changes to potential treatment with drugs that change the underlying biology of Alzheimer's. An estimated 6.7 million Americans age 65 and older are living with Alzheimer's dementia today. This number could grow to 13.8 million by 2060 barring the development of medical breakthroughs to prevent, slow or cure AD. Official death certificates recorded 121,499 deaths from AD in 2019, and Alzheimer's disease was officially listed as the sixth-leading cause of death in the United States. In 2020 and 2021, when COVID-19 entered the ranks of the top ten causes of death, Alzheimer's was the seventh-leading cause of death. Alzheimer's remains the fifth-leading cause of death among Americans age 65 and older. Between 2000 and 2019, deaths from stroke, heart disease and HIV decreased, whereas reported deaths from AD increased more than 145%. This trajectory of deaths from AD was likely exacerbated by the COVID-19 pandemic in 2020 and 2021. More than 11 million family members and other unpaid caregivers provided an estimated 18 billion hours of care to people with Alzheimer's or other dementias in 2022. These figures reflect a decline in the number of caregivers compared with a decade earlier, as well as an increase in the amount of care provided by each remaining caregiver. Unpaid dementia caregiving was valued at $339.5 billion in 2022. Its costs, however, extend to family caregivers' increased risk for emotional distress and negative mental and physical health outcomes - costs that have been aggravated by COVID-19. Members of the paid health care workforce are involved in diagnosing, treating and caring for people with dementia. In recent years, however, a shortage of such workers has developed in the United States. This shortage - brought about, in part, by COVID-19 - has occurred at a time when more members of the dementia care workforce are needed. Therefore, programs will be needed to attract workers and better train health care teams. Average per-person Medicare payments for services to beneficiaries age 65 and older with AD or other dementias are almost three times as great as payments for beneficiaries without these conditions, and Medicaid payments are more than 22 times as great. Total payments in 2023 for health care, long-term care and hospice services for people age 65 and older with dementia are estimated to be $345 billion. The Special Report examines whether there will be sufficient numbers of physician specialists to provide Alzheimer's care and treatment now that two drugs are available that change the underlying biology of Alzheimer's disease.

The evolution of comprehensive genetic analysis in neurology: Implications for precision medicine

Technological advancements have facilitated the availability of reliable and thorough genetic analysis in many medical fields, including neurology. In this review, we focus on the importance of selecting the appropriate genetic test to aid in the accurate identification of disease utilizing currently employed technologies for analyzing monogenic neurological disorders. Moreover, the applicability of comprehensive analysis via NGS for various genetically heterogeneous neurological disorders is reviewed, revealing its efficiency in clarifying a frequently cloudy diagnostic picture and delivering a conclusive and solid diagnosis that is essential for the proper management of the patient. The feasibility and effectiveness of medical genetics in neurology require interdisciplinary cooperation among several medical specialties and geneticists, to select and perform the most relevant test according to each patient's medical history, using the most appropriate technological tools. The prerequisites for a comprehensive genetic analysis are discussed, highlighting the utility of appropriate gene selection, variant annotation, and classification. Moreover, genetic counseling and interdisciplinary collaboration could improve diagnostic yield further. Additionally, a sub-analysis is conducted on the 1,502,769 variation records with submitted interpretations in the Clinical Variation (ClinVar) database, with a focus on neurology-related genes, to clarify the value of suitable variant categorization. Finally, we review the current applications of genetic analysis in the diagnosis and personalized management of neurological patients and the advances in the research and scientific knowledge of hereditary neurological disorders that are evolving the utility of genetic analysis towards the individualization of the treatment strategy.

Shared and unique effects of ApoEε4 and pathogenic gene mutation on cognition and imaging in preclinical familial Alzheimer's disease

BACKGROUND

Neuropsychology and imaging changes have been reported in the preclinical stage of familial Alzheimer's disease (FAD). This study investigated the effects of APOEε4 and known pathogenic gene mutation on different cognitive domains and circuit imaging markers in preclinical FAD.

METHODS

One hundred thirty-nine asymptomatic subjects in FAD families, including 26 APOEε4 carriers, 17 APP and 20 PS1 mutation carriers, and 76 control subjects, went through a series of neuropsychological tests and MRI scanning. Test scores and imaging measures including volumes, diffusion indices, and functional connectivity (FC) of frontostriatal and hippocampus to posterior cingulate cortex pathways were compared between groups and analyzed for correlation.

RESULTS

Compared with controls, the APOEε4 group showed increased hippocampal volume and decreased FC of fronto-caudate pathway. The APP group showed increased recall scores in auditory verbal learning test, decreased fiber number, and increased radial diffusivity and FC of frontostriatal pathway. All three genetic groups showed decreased fractional anisotropy of hippocampus to posterior cingulate cortex pathway. These neuropsychological and imaging measures were able to discriminate genetic groups from controls, with areas under the curve from 0.733 to 0.837. Circuit imaging measures are differentially associated with scores in various cognitive scales in control and genetic groups.

CONCLUSIONS

There are neuropsychological and imaging changes in the preclinical stage of FAD, some of which are shared by APOEε4 and known pathogenic gene mutation, while some are unique to different genetic groups. These findings are helpful for the early identification of Alzheimer's disease and for developing generalized and individualized prevention and intervention strategies.

Young-onset dementia: A systematic review of the psychological and social impact on relatives

OBJECTIVE

Young-onset dementia (YOD) has significant impact for the affected person, but also has far-reaching effects on the family. Additionally, biological relatives have an increased genetic risk of developing the condition themselves. This review aimed to identify the psychological and social impacts of YOD in the family, for asymptomatic relatives.

METHODS

A systematic review of key databases for empirical studies about the lived experience of biological relatives at risk for YOD was performed. Data was collated and interpreted via narrative synthesis.

RESULTS

The majority of the nineteen included studies were qualitative and explored the experiences of children with a parent with YOD. Five themes were developed: (1) Onset of YOD disrupts family functioning (2) Emotional impact is significant and varied (3) Uncertain future (due to uncertainty of diagnosis, care-giving responsibilities, and their own increased genetic risk) (4) Lack of visibility in health care and society (5) Coping strategies include physical/cognitive distancing, and emotion-focused coping.

CONCLUSION

Our findings demonstrate a diagnosis of YOD significantly impacts the lives of relatives, yet their experiences and needs often go unnoticed.

PRACTICE IMPLICATIONS

We present a practical framework of questions and strategies for care of relatives, mapped to the self-regulation model of genetic counselling.

Attitudes, Motivations, and Barriers to Pre-Symptomatic Alzheimer's Disease Screening: Development and Validation of the 'Perceptions regarding pRE-symptomatic Alzheimer's Disease Screening' (PRE-ADS) Questionnaire

BACKGROUND

Pre-symptomatic screening methods for detecting a higher risk of Alzheimer's disease (AD) are gaining popularity; thus, more people are seeking these tests. However, to date, not much is known about the attitudes toward pre-symptomatic AD screening.

OBJECTIVE

The goal of this study is to examine the psychometric properties of a tool for assessing the attitudes, barriers, and motivations to pre-symptomatic AD screening.

METHODS

This is a cross-sectional study performed on 208 Greek participants (189 students and 19 caregivers) provided with an online questionnaire. Psychometric properties were assessed through the examination of its construct validity (principal component analysis) and internal consistency.

RESULTS

Exploratory factor analysis revealed the presence of four factors. The first factor is labeled as "Perceived harms of testing" (10 items), the second "Acceptance of testing" (5 items), the third "Perceived benefits of testing" (6 items), and the fourth factor "Need for knowledge" (4 items). The reliability (internal consistency) of each factor separately was acceptable to good (0.70-0.87) while the internal consistency of the overall questionnaire (25 items) was good (Cronbach's α=0.82).

CONCLUSION

PRE-ADS is a valid questionnaire that might help in the research of peoples' attitudes related to the pros and cons of pre-symptomatic screening for AD, and the development of effective counseling programs and prevention strategies. However, future research is required in the target population.

Disclosure of Genetic Risk Factors for Alzheimer's Disease to Cognitively Healthy Individuals-From Current Practice towards a Personalised Medicine Scenario

Alzheimer's disease (AD) is a genetically complex disorder. In addition to the relatively small number of pathogenic variants causing autosomal dominant AD, many others have been associated with the much more common sporadic form. The E4 allele of the Apolipoprotein E (APOE) is the first discovered genetic risk factor for AD. In addition, more than 70 genetic risk loci contributing to AD have been identified. Current guidelines do not recommend AD susceptibility genetic testing in cognitively healthy adults because the implications for clinical care are limited. However, secondary prevention clinical trials of disease-modifying therapies enrol individuals based on genetic criteria, and participants are often informed of APOE testing results. Moreover, the availability of direct-to-consumer genetic testing allows individuals to learn their own AD genetic risk profile without medical supervision. A number of research protocols for AD susceptibility genetic testing have been proposed. In Italy, disclosure processes and protocols beyond those developed for inherited dementia have not been established yet. We reviewed the literature on the current practice and clinical issues related to disclosing AD genetic risk to cognitively healthy individuals and provide suggestions that may help to develop specific guidelines at the national level.

Cognitive Impairment in Older Adults: Epidemiology, Diagnosis, and Treatment

Cognitive impairment and dementia affect dozens of millions of people worldwide and cause significant distress to patients and caregivers and a financial burden to families and health care systems. Careful history-taking, cognitive and physical examination, and supplemental neuroimaging and fluid-based biomarkers can accurately diagnose neurocognitive disorders. Management includes non-pharmacological and pharmacological treatments tailored to the etiology and to the individual.

[National survey of presymptomatic genetic testing for adult-onset hereditary neuromuscular diseases-system development for after the establishment of therapies]

As therapies for hereditary neuromuscular diseases are developed, the need for presymptomatic genetic testing and genetic counseling for early treatment is expected to increase. In Japan, there is no uniformly recommended protocol for presymptomatic genetic testing. In order to provide basic data for the establishment of a presymptomatic genetic testing system, we surveyed medical genetics departments in Japan about their current status (response rate: 67.4%). The questionnaire survey revealed that approximately 60% of facilities had established their own procedures for presymptomatic genetic testing, but the approaches used varied from facility to facility. The interview survey enabled us to identify the essential factors for the establishment of a presymptomatic genetic testing system for each case, each facility, and at the overall level. In the future, there is a need to develop a standardized protocol to help establish a presymptomatic genetic testing system.

People's interest in brain health testing: Findings from an international, online cross-sectional survey

Brain health entails mental wellbeing and cognitive health in the absence of brain disorders. The past decade has seen an explosion of tests, cognitive and biological, to predict various brain conditions, such as Alzheimer's Disease. In line with these current developments, we investigated people's willingness and reasons to-or not to-take a hypothetical brain health test to learn about risk of developing a brain disease, in a cross-sectional multilanguage online survey. The survey was part of the Global Brain Health Survey, open to the public from 4th June 2019 to 31st August 2020. Respondents were largely recruited via European brain councils and research organizations. 27,590 people responded aged 18 years or older and were predominantly women (71%), middle-aged or older (>40 years; 83%), and highly educated (69%). Responses were analyzed to explore the relationship between demographic variables and responses.

Results

We found high public interest in brain health testing: over 91% would definitely or probably take a brain health test and 86% would do so even if it gave information about a disease that cannot be treated or prevented. The main reason for taking a test was the ability to respond if one was found to be at risk of brain disease, such as changing lifestyle, seeking counseling or starting treatment. Higher interest in brain health testing was found in men, respondents with lower education levels and those with poor self-reported cognitive health.

Conclusion

High public interest in brain health and brain health testing in certain segments of society, coupled with an increase of commercial tests entering the market, is likely to put pressure on public health systems to inform the public about brain health testing in years to come.

The Clinical Use of Alzheimer's Disease Biomarkers in Patients with Mild Cognitive Impairment: A European Alzheimer's Disease Consortium Survey

BACKGROUND

Recent advances occurred in the field of Alzheimer's disease (AD) biomarkers and the introduction of a research framework grounded on a biomarker-based definition of AD might have fostered an increased clinical use of AD biomarkers. For this reason, an up-to-date depiction of the clinical use of AD biomarkers is needed.

OBJECTIVE

To investigate the clinical use of the main AD biomarkers in patients with mild cognitive impairment (MCI) by examining the beliefs and preferences of professionals (clinicians and biomarker experts) of the European Alzheimer's Disease Consortium (EADC).

METHODS

150 professionals filled in an online survey from May to September 2020. The investigated biomarkers were medial temporal lobe atrophy score (MTA) on structural MRI, typical AD (i.e., temporoparietal and posterior cingulate) hypometabolism on FDG-PET, CSF (Aβ42, p-tau, t-tau), amyloid-PET and tau-PET.

RESULTS

The frequency of responders reporting a frequent-to-constant use of MTA (77%) is higher than that of those reporting a frequent-to-constant use of the other AD biomarkers (i.e.

, CSF

45%, p = 0.014; FDG-PET: 32%, p &lt; 0.001; amyloid-PET: 8%, p &lt; 0.001; and tau-PET: 2%, p &lt; 0.001). CSF is considered the most valuable biomarker in terms of additional diagnostic value, followed by amyloid-PET, tau-PET, and typical AD hypometabolism on FDG-PET.

CONCLUSION

AD biomarkers are widely used across European memory clinics with a clinical research background for the diagnosis of MCI. Overall, we observed that CSF is currently considered as the most useful biomarker, followed by amyloid-PET.

Neurocognitive trajectory and proteomic signature of inherited risk for Alzheimer's disease

For Alzheimer's disease-a leading cause of dementia and global morbidity-improved identification of presymptomatic high-risk individuals and identification of new circulating biomarkers are key public health needs. Here, we tested the hypothesis that a polygenic predictor of risk for Alzheimer's disease would identify a subset of the population with increased risk of clinically diagnosed dementia, subclinical neurocognitive dysfunction, and a differing circulating proteomic profile. Using summary association statistics from a recent genome-wide association study, we first developed a polygenic predictor of Alzheimer's disease comprised of 7.1 million common DNA variants. We noted a 7.3-fold (95% CI 4.8 to 11.0; p < 0.001) gradient in risk across deciles of the score among 288,289 middle-aged participants of the UK Biobank study. In cross-sectional analyses stratified by age, minimal differences in risk of Alzheimer's disease and performance on a digit recall test were present according to polygenic score decile at age 50 years, but significant gradients emerged by age 65. Similarly, among 30,541 participants of the Mass General Brigham Biobank, we again noted no significant differences in Alzheimer's disease diagnosis at younger ages across deciles of the score, but for those over 65 years we noted an odds ratio of 2.0 (95% CI 1.3 to 3.2; p = 0.002) in the top versus bottom decile of the polygenic score. To understand the proteomic signature of inherited risk, we performed aptamer-based profiling in 636 blood donors (mean age 43 years) with very high or low polygenic scores. In addition to the well-known apolipoprotein E biomarker, this analysis identified 27 additional proteins, several of which have known roles related to disease pathogenesis. Differences in protein concentrations were consistent even among the youngest subset of blood donors (mean age 33 years). Of these 28 proteins, 7 of the 8 proteins with concentrations available were similarly associated with the polygenic score in participants of the Multi-Ethnic Study of Atherosclerosis. These data highlight the potential for a DNA-based score to identify high-risk individuals during the prolonged presymptomatic phase of Alzheimer's disease and to enable biomarker discovery based on profiling of young individuals in the extremes of the score distribution.

How we approach genetics in the diagnosis and management of vascular anomalies

Vascular anomalies are a heterogeneous group of disorders that are currently classified based on their clinical and histological characteristics. Over the past decade, there have been significant advances in molecular genetics that have led to identification of genetic alterations associated with vascular tumors, vascular malformations, and syndromes. Here, we describe known genetic alterations in vascular anomalies, discuss when and how to test, and examine how identification of causative genetic mutations provides for better management of these disorders through improved understanding of their pathogenesis and increasing use of targeted therapeutic agents in order to achieve better outcomes for our patients.

A Review of CRISPR Cas9 for Alzheimer’s Disease: Treatment Strategies and Could target APOE e4, APP, and PSEN-1 Gene using CRISPR cas9 Prevent the Patient from Alzheimer’s Disease?

   A Review of CRISPR Cas9 for Alzheimer’s Disease: Treatment Strategies and Could target APOE e4, APP, and PSEN-1 Gene using CRISPR cas9 Prevent the Patient from Alzheimer’s Disease? BACKGROUND: Alzheimer’s disease is a neurodegenerative disorder characterized by the formation of β-amyloid plaques and neurofibrillary tangles from hyperphosphorylated tau. Several studies suggest that targeting the deletion of the APOE e4, PSEN-1, and APP will reduce tau phosphorylation and Aβ protein accumulation, a crucial hypothesis for the causation of Alzheimer’s disease. APOE e4, PSEN-1, and APP with genome editing Clustered Regular interspersed Short Palindromic Repeats-CRISPR-related (CRISPR/Cas9) are thought to have therapeutic promise for Alzheimer’s disease.AIM: The purpose of this study was to determine whether targeting APOE e4, PSEN-1, and APP using CRISPR/Cas9 is an effective therapeutic and whether it has a long-term effect on Alzheimer’s disease.METHODS: The method used in this study summarized articles by examining the titles and abstracts of specific specified keywords. In this situation, the author picked the title and abstract that matched PubMed, Google Scholar, Science Direct, Cochrane, and the Frontiers in Neuroscience; this was followed by checking to see whether the paper was available in full-text. Eventually, the researcher will study the entire article to decide if it is valuable and relevant to the issue.RESULTS: CRISPR/Cas9 deletion of APOE e4, PSEN-1, and APP in induced pluripotent stem cells (iPSC’s) and g2576 mice as APP mutant models reduce tau phosphorylation and Aβ protein accumulation from neurofibrillary tangles and prevent cell death, vascular damage, and dementia. Furthermore, CRISPR/Cas9 deletion in APOE e4, PSEN-1, and APP improved neuronal cell resilience to oxidative stress and inflammation.CONCLUSION: APOE e4, PSEN-1, and APP deletion by genome editing CRISPR/Cas9 is effective to reduce tau phosphorylation and Aβ protein accumulation from neurofibrillary tangles, cell death, vascular damage, and dementia. However, further research is needed to determine the side effects and safety of its use.

Genetics of Alzheimer Disease

PURPOSE OF REVIEW

This article discusses the spectrum of genetic risk in familial and sporadic forms of early- and late-onset Alzheimer disease (AD). Recent work illuminating the complex genetic architecture of AD is discussed in the context of high and low risk and what is known in different populations.

RECENT FINDINGS

A small proportion of AD is autosomal dominant familial AD caused by variants in PSEN1, PSEN2, or APP, although more recently described rare genetic changes can also increase risk substantially over the general population, with odds ratios estimated at 2 to 4. APOE remains the strongest genetic risk factor for late-onset AD, and understanding the biology of APOE has yielded mechanistic insights and leads for therapeutic interventions. Genome-wide studies enabled by rapidly developing technologic advances in sequencing have identified numerous risk factors that have a low impact on risk but are widely shared throughout the population and involve a repertoire of cell pathways, again shining light on potential paths to intervention. Population studies aimed at defining and stratifying genetic AD risk have been informative, although they are not yet widely applicable clinically because the studies were not performed in people with diverse ancestry and ethnicity and thus population-wide data are lacking.

SUMMARY

The value of genetic information to practitioners in the clinic is distinct from information sought by researchers looking to identify novel therapeutic targets. It is possible to envision a future in which genetic stratification joins other biomarkers to facilitate therapeutic choices and inform prognosis. Genetics already has transformed our understanding of AD pathogenesis and will, no doubt, continue to reveal the complexity of brain biology in health and disease.

Association of the top 20 Alzheimer's disease risk genes with [18F]flortaucipir PET

Introduction

We previously reported genetic associations of the top Alzheimer's disease (AD) risk alleles with amyloid deposition and neurodegeneration. Here, we report the association of these variants with [18F]flortaucipir standardized uptake value ratio (SUVR).

Methods

We analyzed the [18F]flortaucipir scans of 352 cognitively normal (CN), 160 mild cognitive impairment (MCI), and 54 dementia (DEM) participants from Alzheimer's Disease Neuroimaging Initiative (ADNI)2 and 3. We ran step-wise regression with log-transformed [18F]flortaucipir meta-region of interest SUVR as the outcome measure and genetic variants, age, sex, and apolipoprotein E (APOE) ε4 as predictors. The results were visualized using parametric mapping at familywise error cluster-level-corrected P < .05.

Results

APOE ε4 showed significant (P < .05) associations with tau deposition across all disease stages. Other significantly associated genes include variants in ABCA7 in CN, CR1 in MCI, BIN1 and CASS4 in MCI and dementia participants.

Discussion

We found significant associations to tau deposition for ABCA7, BIN1, CASS4, and CR1, in addition to APOE ε4. These four variants have been previously associated with tau metabolism through model systems.

Genetic investigation of dementias in clinical practice

BACKGROUND

The field of neurodegenerative dementia genetics has advanced significantly over the past two decades, but there are still more to be discovered (such as the gene mutation in some familial forms of dementia).

OBJECTIVE

to provide a brief review of the most recent discoveries regarding monogenic dementia, and covering the most frequent genetic diseases that can cause dementia (neurodegenerative or not).

METHODS

a review of the literature will be carried out.

RESULTS

neurodegenerative dementias, vascular dementias and leukoencephalopathies caused by single pathogenic variants are presented.

CONCLUSION

The spectrum of clinical presentations for most of the genes discussed is wide, and hence genetic testing in clinic should try to cover as many genes as possible.

What contribution can genetics make to predict the risk of Alzheimer's disease?

Alzheimer's disease (AD) is the most common neurodegenerative disorder. Although its etiology remains incompletely understood, genetic variants are important contributors. The prediction of AD risk through individual genetic variants is an important topic of research that may have individual and societal consequences when preventive treatments will become available. However, the genetic substratum of AD is heterogeneous. In addition to the extremely rare and fully penetrant pathogenic variants of the PSEN1, PSEN2 or APP genes causing autosomal dominant AD, a large spectrum of risk factors have been identified in complex forms, including the common risk factor APOEɛ4, which is associated with a moderate-to-high risk, common polymorphisms associated with a modest individual risk, and a plethora of rare variants in genes like SORL1, TREM2 or ABCA7 with moderate to high-magnitude effect. Understanding how these genetic factors contribute to AD risk in a given individual, in additional to non-genetic factors, remains a challenge. Over the last 10 years, age-related penetrance curves have progressively incorporated advances in the knowledge of AD genetics, from APOE to common polygenic components and, currently, SORL1 rare variants, which represents an important step towards precision medicine in AD. In this review, we present the complex genetic architecture of AD and we expose the prediction of AD risk according to its underlying genetic component.

Psychological Impact of Predictive Genetic Testing for Inherited Alzheimer Disease and Frontotemporal Dementia: The IT-DIAfN Protocol

AIM

Our aim was to evaluate the psychological impact of predictive genetic testing in individuals at-risk for inherited dementia who underwent a structured counseling and testing protocol.

METHODS

Participants were healthy at-risk relatives from families with at least one affected patient, in whom a disease-associated genetic variant had been ascertained. A comprehensive psychological assessment (personality, anxiety and depression, quality of life, coping strategies, resilience and health-related beliefs) was administered at baseline, at 6 months and 12 months follow-up.

RESULTS

Twenty-four participants from 13 families were included. Sixteen participants underwent blood sampling and genetic analysis; 6 resulted to be carriers of pathogenic variants (1 in PSEN1, 1 in PSEN2, 4 in GRN). Carriers showed higher score on the Resilience Scale for Adults (RSA) - social competence, and on Multidimensional Health Locus of Control - internal, than noncarriers (P=0.03 for both). Ten at-risk relatives who completed the follow-up showed improvement in RSA - planned future (P=0.01) with respect to baseline.

DISCUSSION

Our case series showed that at-risk individuals undergoing predictive testing showed benefit on personal life and no detrimental impact on a broad range of psychological outcomes. Higher social skills and lower internal health locus of control in carriers may be an early psychological correlate of preclinical dementia.

2022 Alzheimer's disease facts and figures

This article describes the public health impact of Alzheimer's disease (AD), including incidence and prevalence, mortality and morbidity, use and costs of care, and the overall impact on family caregivers, the dementia workforce and society. The Special Report discusses consumers' and primary care physicians' perspectives on awareness, diagnosis and treatment of mild cognitive impairment (MCI), including MCI due to Alzheimer's disease. An estimated 6.5 million Americans age 65 and older are living with Alzheimer's dementia today. This number could grow to 13.8 million by 2060 barring the development of medical breakthroughs to prevent, slow or cure AD. Official death certificates recorded 121,499 deaths from AD in 2019, the latest year for which data are available. Alzheimer's disease was officially listed as the sixth-leading cause of death in the United States in 2019 and the seventh-leading cause of death in 2020 and 2021, when COVID-19 entered the ranks of the top ten causes of death. Alzheimer's remains the fifth-leading cause of death among Americans age 65 and older. Between 2000 and 2019, deaths from stroke, heart disease and HIV decreased, whereas reported deaths from AD increased more than 145%. More than 11 million family members and other unpaid caregivers provided an estimated 16 billion hours of care to people with Alzheimer's or other dementias in 2021. These figures reflect a decline in the number of caregivers compared with a decade earlier, as well as an increase in the amount of care provided by each remaining caregiver. Unpaid dementia caregiving was valued at $271.6 billion in 2021. Its costs, however, extend to family caregivers' increased risk for emotional distress and negative mental and physical health outcomes - costs that have been aggravated by COVID-19. Members of the dementia care workforce have also been affected by COVID-19. As essential care workers, some have opted to change jobs to protect their own health and the health of their families. However, this occurs at a time when more members of the dementia care workforce are needed. Average per-person Medicare payments for services to beneficiaries age 65 and older with AD or other dementias are almost three times as great as payments for beneficiaries without these conditions, and Medicaid payments are more than 22 times as great. Total payments in 2022 for health care, long-term care and hospice services for people age 65 and older with dementia are estimated to be $321 billion. A recent survey commissioned by the Alzheimer's Association revealed several barriers to consumers' understanding of MCI. The survey showed low awareness of MCI among Americans, a reluctance among Americans to see their doctor after noticing MCI symptoms, and persistent challenges for primary care physicians in diagnosing MCI. Survey results indicate the need to improve MCI awareness and diagnosis, especially in underserved communities, and to encourage greater participation in MCI-related clinical trials.

Biosensor approaches on the diagnosis of neurodegenerative diseases: Sensing the past to the future

Early diagnosis of neurodegeneration-oriented diseases that develop with the aging world is essential for improving the patient's living conditions as well as the treatment of the disease. Alzheimer's and Parkinson's diseases are prominent examples of neurodegeneration characterized by dementia leading to the death of nerve cells. The clinical diagnosis of these diseases only after the symptoms appear, delays the treatment process. Detection of biomarkers, which are distinctive molecules in biological fluids, involved in neurodegeneration processes, has the potential to allow early diagnosis of neurodegenerative diseases. Studies on biosensors, whose main responsibility is to detect the target analyte with high specificity, has gained momentum in recent years with the aim of high detection of potential biomarkers of neurodegeneration process. This study aims to provide an overview of neuro-biosensors developed on the basis of biomarkers identified in biological fluids for the diagnosis of neurodegenerative diseases such as Alzheimer's disease (AD), and Parkinson's disease (PD), and to provide an overview of the urgent needs in this field, emphasizing the importance of early diagnosis in the general lines of the neurodegeneration pathway. In this review, biosensor systems developed for the detection of biomarkers of neurodegenerative diseases, especially in the last 5 years, are discussed.

Alzheimer's disease and sleep disorders: Insights into the possible disease connections and the potential therapeutic targets

One of the comorbid conditions in an individual with Alzheimer's disease is a sleep disorder. Clinical features of sleep disorders involve various sleep disturbances such as Obstructive Sleep Apnea (OSAS), Excessive Daytime Sleepiness (EDS), Rapid Eye Movement (REM), Breathing Disorders, Periodic limb movements in sleep (PLMS), etc. The primary tools used for the identification of such disturbances are Polysomnography (PSG) and Wrist actigraphy. This review will highlight and explains the different approaches used in the treatment of sleep disorders. Non-pharmacological treatments include Peter Hauri rules, sleep education program, and light therapy which play a key role in the regulation of sleep-wake cycles. Pharmacological therapy described in this article may be useful in treating sleep destruction in patients with Alzheimer's disease. Along with the Non-pharmacological and pharmacological treatment, here we discuss five commonly recognized plant-based nutraceuticals with hypothesized impact on sleep disorders: caffeine, chamomile, cherries, L-tryptophan, and valerian by the proper emphasis on the known mechanism of their action.

The Advisory Group on Risk Evidence Education for Dementia: Multidisciplinary and Open to All

The brain changes of Alzheimer's disease and other degenerative dementias begin long before cognitive dysfunction develops, and in people with subtle cognitive complaints, clinicians often struggle to predict who will develop dementia. The public increasingly sees benefits to accessing dementia risk evidence (DRE) such as biomarkers, predictive algorithms, and genetic information, particularly as this information moves from research to demonstrated usefulness in guiding diagnosis and clinical management. For example, the knowledge that one has high levels of amyloid in the brain may lead one to seek amyloid reducing medications, plan for disability, or engage in health promoting behaviors to fight cognitive decline. Researchers often hesitate to share DRE data, either because they are insufficiently validated or reliable for use in individuals, or there are concerns about assuring responsible use and ensuring adequate understanding of potential problems when one's biomarker status is known. Concerns include warning people receiving DRE about situations in which they might be compelled to disclose their risk status potentially leading to discrimination or stigma. The Advisory Group on Risk Evidence Education for Dementia (AGREEDementia) welcomes all concerned with how best to share and use DRE. Supporting understanding in clinicians, stakeholders, and people with or at risk for dementia and clearly delineating risks, benefits, and gaps in knowledge is vital. This brief overview describes elements that made this group effective as a model for other health conditions where there is interest in unfettered collaboration to discuss diagnostic uncertainty and the appropriate use and communication of health-related risk information.

Communicating and Using Dementia Risk Evidence

Advances in biomarkers, genetics, and other data used as dementia risk evidence (DRE) are increasingly informing clinical diagnosis and management. The purpose of this Mini-Forum is to provide a solutions-based discussion of the ethical and legal gaps and practical questions about how to use and communicate these data. Investigators often use DRE in research. When participants ask for their personal results, investigators have concerns. Will data that was intended to study groups be valid for individuals? Will sharing data cause distress? Debates around sharing DRE became heated when blood-based amyloid tests and amyloid reducing drugs appeared poised to enable clinicians easily to identify people with elevated brain amyloid and reduce it with a drug. Such an approach would transform the traditional role of DRE from investigational to foundational; however, then the high costs, uncertain clinical benefits and risks of the therapy led to an urgent need for education to support clinical decision making. Further complicating DRE use are direct to consumer genetic testing and increasingly available biomarker testing. Withholding DRE becomes less feasible and public education around responsible use and understanding become vital. A critical answer to these legal and ethical issues is supporting education that clearly delineates known risks, benefits, and gaps in knowledge, and communication to promote understanding among researchers, clinicians, patients, and all stakeholders. This paper provides an overview and identifies general concepts and resource documents that support more informed discussions for individuals and interdisciplinary groups.

Spillover: The Approval of New Medications for Alzheimer's Disease Dementia Will Impact Biomarker Disclosure Among Asymptomatic Research Participants

In this article we address how the recent, and anticipated upcoming, FDA approvals of novel anti-amyloid medications to treat individuals with mild Alzheimer's disease (AD) dementia could impact disclosure of biomarker results among asymptomatic research participants. Currently, research is typically the context where an asymptomatic individual may have the option to learn their amyloid biomarker status. Asymptomatic research participants who learn their amyloid status may have questions regarding the meaning of this result and the implications for accessing a potential intervention. After outlining our rationale, we provide examples of how current educational materials used in research convey messages regarding amyloid positivity and the availability of treatments, or lack thereof. We suggest language to improve messaging, as well as strengths of current materials, in addressing these issues for research participants. Although novel medications are currently only approved for use among symptomatic individuals, their availability may have implications for disclosure among asymptomatic research participants with evidence of amyloid deposition, who may be especially interested in information on these interventions for potential prevention, or future treatment, of mild cognitive impairment or dementia due to AD.

Association between dementia parental family history and mid-life modifiable risk factors for dementia: a cross-sectional study using propensity score matching within the Lifelines cohort

OBJECTIVE

Individuals with a parental family history (PFH) of dementia have an increased risk to develop dementia, regardless of genetic risks. The aim of this study is to investigate the association between a PFH of dementia and currently known modifiable risk factors for dementia among middle-aged individuals using propensity score matching (PSM).

DESIGN

A cross-sectional study.

SETTING AND PARTICIPANTS

A subsample of Lifelines (35-65 years), a prospective population-based cohort study in the Netherlands was used.

OUTCOME MEASURES

Fourteen modifiable risk factors for dementia and the overall Lifestyle for Brain Health (LIBRA) score, indicating someone's potential for dementia risk reduction (DRR).

RESULTS

The study population included 89 869 participants of which 10 940 (12.2%) had a PFH of dementia (mean (SD) age=52.95 (7.2)) and 36 389 (40.5%) without a PFH of dementia (mean (SD) age=43.19 (5.5)). Of 42 540 participants (47.3%), PFH of dementia was imputed. After PSM, potential confounding variables were balanced between individuals with and without PFH of dementia. Individuals with a PFH of dementia had more often hypertension (OR=1.19; 95% CI 1.14 to 1.24), high cholesterol (OR=1.24; 95% CI 1.18 to 1.30), diabetes (OR=1.26; 95% CI 1.11 to 1.42), cardiovascular diseases (OR=1.49; 95% CI 1.18 to 1.88), depression (OR=1.23; 95% CI 1.08 to 1.41), obesity (OR=1.14; 95% CI 1.08 to 1.20) and overweight (OR=1.10; 95% CI 1.05 to 1.17), and were more often current smokers (OR=1.20; 95% CI 1.14 to 1.27) and ex-smokers (OR=1.21; 95% CI 1.16 to 1.27). However, they were less often low/moderate alcohol consumers (OR=0.87; 95% CI 0.83 to 0.91), excessive alcohol consumers (OR=0.93; 95% CI 0.89 to 0.98), socially inactive (OR=0.84; 95% CI 0.78 to 0.90) and physically inactive (OR=0.93; 95% CI 0.91 to 0.97). Having a PFH of dementia resulted in a higher LIBRA score (RC=0.15; 95% CI 0.11 to 0.19).

CONCLUSION

We found that having a PFH of dementia was associated with several modifiable risk factors. This suggests that middle-aged individuals with a PFH of dementia are a group at risk and could benefit from DRR. Further research should explore their knowledge, beliefs and attitudes towards DRR, and whether they are willing to assess their risk and change their lifestyle to reduce dementia risk.

A Systematic Review and Recommendations Around Frameworks for Evaluating Scientific Validity in Nutritional Genomics

Background: There is a significant lack of consistency used to determine the scientific validity of nutrigenetic research. The aims of this study were to examine existing frameworks used for determining scientific validity in nutrition and/or genetics and to determine which framework would be most appropriate to evaluate scientific validity in nutrigenetics in the future.

Methods: A systematic review (PROSPERO registration: CRD42021261948) was conducted up until July 2021 using Medline, Embase, and Web of Science, with articles screened in duplicate. Gray literature searches were also conducted (June-July 2021), and reference lists of two relevant review articles were screened. Included articles provided the complete methods for a framework that has been used to evaluate scientific validity in nutrition and/or genetics. Articles were excluded if they provided a framework for evaluating health services/systems more broadly. Citing articles of the included articles were then screened in Google Scholar to determine if the framework had been used in nutrition or genetics, or both; frameworks that had not were excluded. Summary tables were piloted in duplicate and revised accordingly prior to synthesizing all included articles. Frameworks were critically appraised for their applicability to nutrigenetic scientific validity assessment using a predetermined categorization matrix, which included key factors deemed important by an expert panel for assessing scientific validity in nutrigenetics.

Results: Upon screening 3,931 articles, a total of 49 articles representing 41 total frameworks, were included in the final analysis (19 used in genetics, 9 used in nutrition, and 13 used in both). Factors deemed important for evaluating nutrigenetic evidence related to study design and quality, generalizability, directness, consistency, precision, confounding, effect size, biological plausibility, publication/funding bias, allele and nutrient dose-response, and summary levels of evidence. Frameworks varied in the components of their scientific validity assessment, with most assessing study quality. Consideration of biological plausibility was more common in frameworks used in genetics. Dose-response effects were rarely considered. Two included frameworks incorporated all but one predetermined key factor important for nutrigenetic scientific validity assessment.

Discussion/Conclusions: A single existing framework was highlighted as optimal for the rigorous evaluation of scientific validity in nutritional genomics, and minor modifications are proposed to strengthen it further.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=261948, PROSPERO [CRD42021261948].

Defining the Critical Components of Informed Consent for Genetic Testing

Purpose: Informed consent for genetic testing has historically been acquired during pretest genetic counseling, without specific guidance defining which core concepts are required. Methods: The Clinical Genome Resource (ClinGen) Consent and Disclosure Recommendations Workgroup (CADRe) used an expert consensus process to identify the core concepts essential to consent for clinical genetic testing. A literature review identified 77 concepts that are included in informed consent for genetic tests. Twenty-five experts (9 medical geneticists, 8 genetic counselors, and 9 bioethicists) completed two rounds of surveys ranking concepts’ importance to informed consent. Results: The most highly ranked concepts included: (1) genetic testing is voluntary; (2) why is the test recommended and what does it test for?; (3) what results will be returned and to whom?; (4) are there other types of potential results, and what choices exist?; (5) how will the prognosis and management be impacted by results?; (6) what is the potential family impact?; (7) what are the test limitations and next steps?; and (8) potential risk of genetic discrimination and legal protections. Conclusion: Defining the core concepts necessary for informed consent for genetic testing provides a foundation for quality patient care across a variety of healthcare providers and clinical indications.

TM2D genes regulate Notch signaling and neuronal function in Drosophila

TM2 domain containing (TM2D) proteins are conserved in metazoans and encoded by three separate genes in each model organism species that has been sequenced. Rare variants in TM2D3 are associated with Alzheimer's disease (AD) and its fly ortholog almondex is required for embryonic Notch signaling. However, the functions of this gene family remain elusive. We knocked-out all three TM2D genes (almondex, CG11103/amaretto, CG10795/biscotti) in Drosophila and found that they share the same maternal-effect neurogenic defect. Triple null animals are not phenotypically worse than single nulls, suggesting these genes function together. Overexpression of the most conserved region of the TM2D proteins acts as a potent inhibitor of Notch signaling at the γ-secretase cleavage step. Lastly, Almondex is detected in the brain and its loss causes shortened lifespan accompanied by progressive motor and electrophysiological defects. The functional links between all three TM2D genes are likely to be evolutionarily conserved, suggesting that this entire gene family may be involved in AD.

Disclosure of individual research results at federally funded Alzheimer's Disease Research Centers

INTRODUCTION

This study describes practices for disclosing individual research results to participants in Alzheimer's disease research.

METHODS

An online survey of clinical core leaders at National Institutes of Health-funded Alzheimer's Disease Research Centers in the United States (response rate: 30/31, 97%) examined return of results practices across nine different types of research results.

RESULTS

Most centers had returned consensus research diagnoses (83%) and neuropsychological test results (73%), with fewer having shared amyloid positron emission tomography (43%), tau imaging (10%), or apolipoprotein E (APOE) genotype (7%) results. Centers reported having disclosed a mean of 3.1 types of results (standard deviation = 2.1; range 0-8). The most commonly cited reason for disclosure was to inform participants' medical decision-making (88%). Disclosure involved multiple professionals and modalities, with neurologists (87%) and in-person visits (85%) most commonplace.

DISCUSSION

Centers varied widely as to whether and how they disclosed research results. Diagnostic and cognitive test results were more commonly returned than genetic or biomarker results.

The Janus-like Association between Proton Pump Inhibitors and Dementia

Early pharmacoepidemiological studies suggested that Proton Pump Inhibitors (PPIs) might increase the risk of Alzheimer’s Disease (AD) and non-AD related dementias. These findings were supported by preclinical studies, specifically stressing the proamyloidogenic and indirect anticholinergic effects of PPIs. However, further large-scale pharmacoepidemiological studies showed inconsistent results on the association between PPIs and dementia. Pharmacodynamically, these findings might be related to the LXR/RXR-mediated amyloid clearance effect and anti-inflammatory action of PPIs. Further aspects that influence PPI effects on AD are related to patient-specific pharmacokinetic and pharmacogenomic characteristics. In conclusion, a personalized (individualized) medicinal approach is necessary to model and predict the potential harmful or beneficial effects of PPIs in AD and non-AD-related dementias in the future.

Evolution of genetic testing supports precision medicine for caring Alzheimer's disease patients

Genetic testing for Alzheimer's disease offers a molecular diagnosis to patients and their relatives and provides information on personal risk, reproductive choices, clinical trial eligibility, and treatment options. In the past, molecular testing was limited to detecting single variations in single genes. Currently, with the advent of next-generation sequencing, simultaneous analysis of more than 100 genes using the same DNA sample is possible. This approach allows the determination of gene mutations, genetic risk factors, genotypes at many pharmacogenomic loci, and the determination of a polygenic risk scores for stratification of risk. This article reviews the diagnostic genetic testing of Alzheimer's disease, from the first molecular approaches to recent advances in NGS, focusing on a precision medicine approach.