Predictive genetic testing for Alzheimer's disease: impact upon risk perception

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.

Safety and Tolerability of APOE Genotyping and Disclosure in Cognitively Normal Volunteers From the Butler Alzheimer's Prevention Registry

AIMS

Alzheimer's disease (AD) is a gradually progressive neurodegenerative disease that ultimately results in total loss of cognitive and functional independence in older adults. This study aimed to examine the safety and tolerability of APOE disclosure in community-dwelling, cognitively normal (CN) older adults from the Butler Alzheimer's Prevention Registry (BAPR), and to determine whether APOE disclosure impacted participant's decisions to participate in AD clinical research.

METHODS

186 (N = 106 ∊4 non-carriers, 80 ∊4 carriers) CN older adults aged 58-78 from the BAPR completed 2 visits: one for psychological readiness screening and genotyping and one for APOE disclosure. Online follow-ups were completed 3 days, 6 weeks, and 6 months post-disclosure. Primary outcomes were scores on self-report measures of depression, anxiety, impact of events, and perceived risk of AD, along with enrollment in AD clinical trials.

RESULTS

∊4 carriers and non-carriers did not differ significantly on measures of depression, anxiety, or suicidal ideation over the 6-month follow-up period. ∊4 carriers reported higher impact of disclosure than non-carriers immediately after disclosure, but both groups' scores on impact of events measures remained sub-clinical. ∊4 carriers and non-carriers were equally likely to participate in AD research after disclosure, with genotype-dependent differences in type of clinical trial enrollment.

CONCLUSIONS

APOE genotyping and disclosure was safe and well tolerated in a group of CN, community-dwelling older adults, who were pre-screened after volunteering for AD research through BAPR. Implications for the inclusion of APOE genotyping and disclosure at AD clinical trial sites are discussed.

Impact of Personalized Genetic Breast Cancer Risk Estimation With Polygenic Risk Scores on Preventive Endocrine Therapy Intention and Uptake

Endocrine therapy is underutilized to reduce breast cancer incidence among women at increased risk. Polygenic risk scores (PRSs) assessing 77 breast cancer genetic susceptibility loci personalizes risk estimates. We examined effect of personalized PRS breast cancer risk prediction on intention to take and endocrine therapy uptake among women at increased risk. Eligible participants had a 10-year breast cancer risk ≥5% by Tyrer-Cuzick model [International Breast Cancer Intervention Study (IBIS)] or ≥3.0 % 5-year Gail Model risk with no breast cancer history or hereditary breast cancer syndrome. Breast cancer risk was estimated, endocrine therapy options were discussed, and endocrine therapy intent was assessed at baseline. After genotyping, PRS-updated breast cancer risk estimates, endocrine therapy options, and intent to take endocrine therapy were reassessed; endocrine therapy uptake was assessed during follow-up. From March 2016 to October 2017, 151 patients were enrolled [median (range) age, 56.1 (36.0-76.4 years)]. Median 10-year and lifetime IBIS risks were 7.9% and 25.3%. Inclusion of PRS increased lifetime IBIS breast cancer risk estimates for 81 patients (53.6%) and reduced risk for 70 (46.4%). Of participants with increased breast cancer risk by PRS, 39 (41.9%) had greater intent to take endocrine therapy; of those with decreased breast cancer risk by PRS, 28 (46.7%) had less intent to take endocrine therapy (P < 0.001). On multivariable regression, increased breast cancer risk by PRS was associated with greater intent to take endocrine therapy (P < 0.001). Endocrine therapy uptake was greater among participants with increased breast cancer risk by PRS (53.4%) than with decreased risk (20.9%; P < 0.001). PRS testing influenced intent to take and endocrine therapy uptake. Assessing PRS effect on endocrine therapy adherence is needed.Prevention Relevance: Counseling women at increased breast cancer risk using polygenic risk score (PRS) risk estimates can significantly impact preventive endocrine therapy uptake. Further development of PRS testing to personalize breast cancer risk assessments and endocrine therapy counselling may serve to potentially reduce the incidence of breast cancer in the future.

Genetic Sample Provision Among National Alzheimer's Coordinating Center Participants

BACKGROUND

Genetic data help detect preclinical Alzheimer's disease and target individuals for clinical trials, making genetic research engagement critical for continued advancement in dementia prevention and treatment.

OBJECTIVE

To understand what individual and institutional factors may relate to provision of genetic samples within the Alzheimer's Disease Centers.

METHODS

Data from the National Alzheimer's Coordinating Center Uniform Data Set (2009-2016) were obtained along with genetic sample availability. Logistic regression was used to assess independent contributions of demographic and clinical characteristics to the probability of sample provision. Sites contributing data completed a brief survey exploring regulatory and scientific issues related to genetic research engagement.

RESULTS

Just over half (52.1%) of the 27,519 unique participants had genetic data available. Female sex, white race, non-Hispanic ethnicity, normal cognition, and greater than 5 years of follow-up were associated with greater probability of availability. Sites identified refusals as the most frequent barrier to sample provision, followed by staff availability.

CONCLUSION

These results highlight the importance of strategies to promote minority engagement and encourage earlier genetic research participation.

Predictive Genetic Counseling for Neurodegenerative Diseases: Past, Present, and Future

Predictive genetic counseling for neurodegenerative diseases commenced with Huntington's disease (HD). Because the psychological issues and outcomes have been best studied in HD, the HD genetic counseling and testing protocol is still accepted as the gold standard for genetic counseling for these diseases. Yet, advances in genomic technology have produced an abundance of new information about the genetics of diseases such as Alzheimer's disease, frontotemporal dementia, amyotrophic lateral sclerosis, and Parkinson's disease. The resulting expansion of genetic tests together with the availability of direct-to-consumer testing and clinical trials for treatment of these diseases present new ethical and practical issues requiring modifications to the protocol for HD counseling and new demands on both physicians and genetic counselors. This work reviews the history of genetic counseling for neurodegenerative diseases, its current practice, and the future direction of genetic counseling for these conditions.

Neutral, Negative, or Negligible? Changes in Patient Perceptions of Disease Risk Following Receipt of a Negative Genomic Screening Result

Most individuals who undergo genomic screening will receive negative results or results not sufficient to warrant a clinical response. Even though a majority of individuals receive negative results, little is known about how negative results may impact individuals' perception of disease risk. Changes in risk perception (specifically reductions in perceived risk) may affect both probands and their family members if inaccurate information is communicated to family members. We surveyed patients who received negative results as part of their participation in a genomic screening study and assessed their perceptions of disease risk following receipt of results. Participants had either hyperlipidemia or colon polyps (or both) and received their negative genomic screening results by mail. Of 1712 total individuals recruited, 1442 completed the survey (84.2% completion rate). Approximately one quarter of individuals believed their risk for heart disease to be lower and approximately one third of individuals believed their risk for colon cancer to be lower after receiving and evaluating their negative genomic screening result. 78% of those who believed their risk for one or both diseases had declined had already shared or intended to share their result with family members. Our study suggests patients may interpret a negative genomic screening result as implying a reduction in their overall disease risk.

Psychological, behavioral and social effects of disclosing Alzheimer's disease biomarkers to research participants: a systematic review

BACKGROUND

Current Alzheimer's disease (AD) research initiatives focus on cognitively healthy individuals with biomarkers that are associated with the development of AD. It is unclear whether biomarker results should be returned to research participants and what the psychological, behavioral and social effects of disclosure are. This systematic review therefore examines the psychological, behavioral and social effects of disclosing genetic and nongenetic AD-related biomarkers to cognitively healthy research participants.

METHODS

We performed a systematic literature search in eight scientific databases. Three independent reviewers screened the identified records and selected relevant articles. Results extracted from the included articles were aggregated and presented per effect group.

RESULTS

Fourteen studies met the inclusion criteria and were included in the data synthesis. None of the identified studies examined the effects of disclosing nongenetic biomarkers. All studies but one concerned the disclosure of APOE genotype and were conducted in the USA. Study populations consisted largely of cognitively healthy first-degree relatives of AD patients. In this group, disclosure of an increased risk was not associated with anxiety, depression or changes in perceived risk in relation to family history. Disclosure of an increased risk did lead to an increase in specific test-related distress levels, health-related behavior changes and long-term care insurance uptake and possibly diminished memory functioning.

CONCLUSION

In cognitively healthy research participants with a first-degree relative with AD, disclosure of APOE ε4-positivity does not lead to elevated anxiety and depression levels, but does increase test-related distress and results in behavior changes concerning insurance and health. We did not find studies reporting the effects of disclosing nongenetic biomarkers and only one study included people without a family history of AD. Empirical studies on the effects of disclosing nongenetic biomarkers and of disclosure to persons without a family history of AD are urgently needed.

TRIAL REGISTRATION

PROSPERO international prospective register for systematic reviews CRD42016035388 . Registered 19 February 2016.

Developing patient-friendly genetic and genomic test reports: formats to promote patient engagement and understanding

With the emergence of electronic medical records and patient portals, patients are increasingly able to access their health records, including laboratory reports. However, laboratory reports are usually written for clinicians rather than patients, who may not understand much of the information in the report. While several professional guidelines define the content of test reports, there are no guidelines to inform the development of a patient-friendly laboratory report. In this Opinion, we consider patient barriers to comprehension of lab results and suggest several options to reformat the lab report to promote understanding of test results and their significance to patient care, and to reduce patient anxiety and confusion. In particular, patients’ health literacy, genetic literacy, e-health literacy and risk perception may influence their overall understanding of lab results and affect patient care. We propose four options to reformat lab reports: 1) inclusion of an interpretive summary section, 2) a summary letter to accompany the lab report, 3) development of a patient user guide to be provided with the report, and 4) a completely revised patient-friendly report. The complexity of genetic and genomic test reports poses a major challenge to patient understanding that warrants the development of a report more appropriate for patients.

A review of quality of life after predictive testing for and earlier identification of neurodegenerative diseases

The past decade has witnessed an explosion of evidence suggesting that many neurodegenerative diseases can be detected years, if not decades, earlier than previously thought. To date, these scientific advances have not provoked any parallel translational or clinical improvements. There is an urgency to capitalize on this momentum so earlier detection of disease can be more readily translated into improved health-related quality of life for families at risk for, or suffering with, neurodegenerative diseases. In this review, we discuss health-related quality of life (HRQOL) measurement in neurodegenerative diseases and the importance of these "patient reported outcomes" for all clinical research. Next, we address HRQOL following early identification or predictive genetic testing in some neurodegenerative diseases: Huntington disease, Alzheimer's disease, Parkinson's disease, Dementia with Lewy bodies, frontotemporal dementia, amyotrophic lateral sclerosis, prion diseases, hereditary ataxias, Dentatorubral-pallidoluysian atrophy and Wilson's disease. After a brief report of available direct-to-consumer genetic tests, we address the juxtaposition of earlier disease identification with assumed reluctance toward predictive genetic testing. Forty-one studies examining health-related outcomes following predictive genetic testing for neurodegenerative disease suggested that (a) extreme or catastrophic outcomes are rare; (b) consequences commonly include transiently increased anxiety and/or depression; (c) most participants report no regret; (d) many persons report extensive benefits to receiving genetic information; and (e) stigmatization and discrimination for genetic diseases are poorly understood and policy and laws are needed. Caution is appropriate for earlier identification of neurodegenerative diseases but findings suggest further progress is safe, feasible and likely to advance clinical care.

Effect of communicating DNA based risk assessments for Crohn's disease on smoking cessation: randomised controlled trial

OBJECTIVE

To test the hypothesis that communicating risk of developing Crohn's disease based on genotype and that stopping smoking can reduce this risk, motivates behaviour change among smokers at familial risk.

DESIGN

Parallel group, cluster randomised controlled trial.

SETTING

Families with Crohn's disease in the United Kingdom.

PARTICIPANTS

497 smokers (mean age 42.6 (SD 14.4) years) who were first degree relatives of probands with Crohn's disease, with outcomes assessed on 209/251 (based on DNA analysis) and 217/246 (standard risk assessment).

INTERVENTION

Communication of risk assessment for Crohn's disease by postal booklet based on family history of the disease and smoking status alone, or with additional DNA analysis for the NOD2 genotype. Participants were then telephoned by a National Health Service Stop Smoking counsellor to review the booklet and deliver brief standard smoking cessation intervention. Calls were tape recorded and a random subsample selected to assess fidelity to the clinical protocol.

MAIN OUTCOME MEASURE

The primary outcome was smoking cessation for 24 hours or longer, assessed at six months.

RESULTS

The proportion of participants stopping smoking for 24 hours or longer did not differ between arms: 35% (73/209) in the DNA arm versus 36% (78/217) in the non-DNA arm (difference -1%, 95% confidence interval -10% to 8%, P=0.83). The proportion making a quit attempt within the DNA arm did not differ between those who were told they had mutations putting them at increased risk (36%), those told they had none (35%), and those in the non-DNA arm (36%).

CONCLUSION

Among relatives of patients with Crohn's disease, feedback of DNA based risk assessments does not motivate behaviour change to reduce risk any more or less than standard risk assessment. These findings accord with those across a range of populations and behaviours. They do not support the promulgation of commercial DNA based tests nor the search for gene variants that confer increased risk of common complex diseases on the basis that they effectively motivate health related behaviour change.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN21633644.

"It's not like judgment day": public understanding of and reactions to personalized genomic risk information

The value of genomic risk assessment depends upon patients making appropriate behavioral changes in response to increased risk leading to disease prevention and early detection. To date, few studies have investigated consumers' response to personalized genomic disease risk information. To address this gap, we conducted semi-structured interviews with 60 adults participating in the Coriell Personalized Medicine Collaborative. The interviews took place after receiving results providing genomic and other risk information for up to eight common complex diseases. We found that participants were most likely to recall results which conferred an increased risk or those of particular personal interest. Participants understood the multi-factorial nature of common complex disease, and generally did not have negative emotional responses or overly deterministic perceptions of their results. Although most participants expressed a desire to use results to improve their health, a minority had actually taken action (behavior change or shared results with their doctor) at the time of the interview. These results suggest that participants have a reasonable understanding of genomic risk information and that provision of genomic risk information may motivate behavior change in some individuals; however additional work is needed to better understand the lack of change seen in the majority of participants.

Trial Protocol: Communicating DNA-based risk assessments for Crohn's disease: a randomised controlled trial assessing impact upon stopping smoking

BACKGROUND

Estimates of the risk of developing Crohn's disease (CD) can be made using DNA testing for mutations in the NOD2 (CARD15) gene, family history, and smoking status. Smoking doubles the risk of CD, a risk that is reduced by stopping. CD therefore serves as a timely and novel paradigm within which to assess the utility of predictive genetic testing to motivate behaviour change to reduce the risk of disease. The aim of the study is to describe the impact upon stopping smoking of communicating a risk of developing CD that incorporates DNA analysis. We will test the following main hypothesis:Smokers who are first degree relatives (FDRs) of CD probands are more likely to make smoking cessation attempts following communication of risk estimates of developing CD that incorporate DNA analysis, compared with an equivalent communication that does not incorporate DNA analysis.

METHODS/DESIGN

A parallel groups randomised controlled trial in which smokers who are FDRs of probands with CD are randomly allocated in families to undergo one of two types of assessment of risk for developing CD based on either: i. DNA analysis, family history of CD and smoking status, or ii. Family history of CD and smoking status. The primary outcome is stopping smoking for 24 hours or longer in the six months following provision of risk information. The secondary outcomes are seven-day smoking abstinence at one week and six month follow-ups. Randomisation of 470 smoking FDRs of CD probands, with 400 followed up (85%), provides 80% power to detect a difference in the primary outcome of 14% between randomised arms, at the 5% significance level.

DISCUSSION

This trial provides one of the strongest tests to date of the impact of communicating DNA-based risk assessment on risk-reducing behaviour change. Specific issues regarding the choice of trial design are discussed.

The ethics of disclosing genetic diagnosis for Alzheimer's disease: do we need a new paradigm?

INTRODUCTION OR BACKGROUND

Genetic testing for rare Mendelian disorders represents the dominant ethical paradigm in clinical and professional practice. Predictive testing for Huntington's disease is the model against which other kinds of genetic testing are evaluated, including testing for Alzheimer's disease.

SOURCES OF DATA

This paper retraces the historical development of ethical reasoning in relation to predictive genetic testing and reviews a range of ethical, sociological and psychological literature from the 1970s to the present.

AREAS OF AGREEMENT

In the past, ethical reasoning has embodied a distinct style whereby normative principles are developed from a dominant disease exemplar.

AREAS OF CONTROVERSY

This reductionist approach to formulating ethical frameworks breaks down in the case of disease susceptibility.

GROWING POINTS

Recent developments in the genetics of Alzheimer's disease present a significant case for reconsidering the ethics of disclosing risk for common complex diseases. Disclosing the results of susceptibility testing for Alzheimer's disease has different social, psychological and behavioural consequences. Furthermore, what genetic susceptibility means to individuals and their families is diffuse and often mitigated by other factors and concerns.

AREAS TIMELY FOR DEVELOPING RESEARCH

The ethics of disclosing a genetic diagnosis of susceptibility is contingent on whether professionals accept that probabilistic risk information is in fact 'diagnostic' and it will rely substantially on empirical evidence of how people actually perceive, recall and communicate complex risk information.

The role of disease perceptions and results sharing in psychological adaptation after genetic susceptibility testing: the REVEAL Study

This study evaluates the extent to which psychological adaptation (validated measures of depressive symptoms, anxiety, and test-specific distress) after genetic susceptibility testing is influenced by changes in beliefs about Alzheimer's disease (AD) and sharing of test results with others. Adult children of AD patients (N=269) from a randomized clinical trial involving genetic testing for apolipoprotein E (APOE) provided information before, as well as 6 weeks and 12 months after results disclosure. The levels of adaptation varied highly among participants at 12-month assessment. Participants who learned that they were ε4 negative (lower risk) had a reduction in perceived risk and concern about developing AD compared with those who learned that they were ε4 positive. Those who received results through an extended educational protocol (three in-person visits) had a larger decline in AD concern than those in a condensed protocol (educational brochure and two in-person visits). Increase in AD concern 6 weeks after disclosure was associated with increase in depression scores (b=0.20, P<0.01) and anxiety levels (b=0.20, P<0.01), and higher distress associated with AD genetic testing (b=0.18, P=0.02) 1 year after testing. Increase in perceived risk (b=0.16, P=0.04) was also associated with higher AD genetic testing distress. Sharing the test results with health professionals and friends (but not family) was associated with decrease in depression (b=-0.11, P=0.05) and anxiety levels (b=-0.16, P<0.01), respectively after a year. Enhancing discussion with regard to risks and concerns about AD during pretesting counseling and obtaining support through sharing the results after testing may help facilitate test recipients' long-term psychological adaptation.

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

PURPOSE

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

METHODS

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

RESULTS

Among the 158 participants who accurately recalled their Alzheimer disease risk assessment 6 weeks after risk disclosure, 75 (47.5%) believed their Alzheimer disease risk was more than 5% points different from the Alzheimer disease risk estimate they were given. Within this subgroup, 69.3% believed that their Alzheimer disease risk was higher than what they were told (discordant high), whereas 30.7% believed that their Alzheimer disease risk was lower (discordant low). Participants with a higher baseline risk perception were more likely to have a discordant-high risk perception (P < 0.05). Participants in the discordant-low group were more likely to be APOE epsilon4 positive (P < 0.05) and to score higher on an Alzheimer disease controllability scale (P < 0.05).

CONCLUSION

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

APOE-4 genotype and neurophysiological vulnerability to Alzheimer's and cognitive aging

Many years before receiving a clinical diagnosis of Alzheimer's disease (AD), patients experience evidence of cognitive decline. Recent studies using a variety of brain imaging technologies have detected subtle changes in brain structure and function in normal adults with a genetic risk for AD; these brain changes have similar pathological features as AD, and some appear to be predictive of future cognitive decline. This review examines the most recent data on brain changes in genetic risk for AD and discusses the benefits and potential risks of detecting individuals at risk.

Ethical considerations in psychiatric genetics

Ethical considerations in psychiatric genetics are highly complex and fluid. This review introduces the reader to the wide range of ethical considerations in this field by examining four characteristics of genetic information. First, genetic information may, to a greater or lesser extent, predict a person's future health. Second, learning about one's genotype may have profound psychosocial consequences. Third, genetic information pertains to a person's biological relatives and thus can affect family members, communities, and population groups. Finally, psychiatric genetics is a rapidly evolving field. None of these characteristics is necessarily "exceptional" or unique to genetics, but they provide a useful framework for teasing apart a complex set of ethical considerations. This article reviews conceptual and empirical data that speak to these four characteristics and then presents a set of conceptual frameworks that can be used to systematically analyze the ethics of psychiatric genetic research and clinical genotyping. Finally, directions for future study are described--including the urgent need to gather data on actual risks and benefits of psychiatric genetic research and clinical applications, so that their utility can be assessed and appropriate ethical safeguards identified.

Explaining behavior change after genetic testing: the problem of collinearity between test results and risk estimates

This paper explores whether and how the behavioral impact of genotype disclosure can be disentangled from the impact of numerical risk estimates generated by genetic tests. Secondary data analyses are presented from a randomized controlled trial of 162 first-degree relatives of Alzheimer's disease (AD) patients. Each participant received a lifetime risk estimate of AD. Control group estimates were based on age, gender, family history, and assumed epsilon4-negative apolipoprotein E (APOE) genotype; intervention group estimates were based upon the first three variables plus true APOE genotype, which was also disclosed. AD-specific self-reported behavior change (diet, exercise, and medication use) was assessed at 12 months. Behavior change was significantly more likely with increasing risk estimates, and also more likely, but not significantly so, in epsilon4-positive intervention group participants (53% changed behavior) than in control group participants (31%). Intervention group participants receiving epsilon4-negative genotype feedback (24% changed behavior) and control group participants had similar rates of behavior change and risk estimates, the latter allowing assessment of the independent effects of genotype disclosure. However, collinearity between risk estimates and epsilon4-positive genotypes, which engender high-risk estimates, prevented assessment of the independent effect of the disclosure of an epsilon4 genotype. Novel study designs are proposed to determine whether genotype disclosure has an impact upon behavior beyond that of numerical risk estimates.

Incorporating ethnicity into genetic risk assessment for Alzheimer disease: the REVEAL study experience

PURPOSE

To describe how investigators in a multisite randomized clinical trial addressed scientific and ethical issues involved in creating risk models based on genetic testing for African American participants.

METHODS

The following informed our decision whether to stratify risk assessment by ethnicity: evaluation of epidemiological data, appraisal of benefits and risks of incorporating ethnicity into calculations, and feasibility of creating ethnicity-specific risk curves. Once the decision was made, risk curves were created based on data from a large, diverse study of first-degree relatives of patients with Alzheimer disease.

RESULTS

Review of epidemiological data suggested notable differences in risk between African Americans and whites and that Apolipoprotein E genotype predicts risk in both groups. Discussions about the benefits and risks of stratified risk assessments reached consensus that estimates based on data from whites should not preclude enrolling African Americans, but population-specific risk curves should be created if feasible. Risk models specific to ethnicity, gender, and Apolipoprotein E genotype were subsequently developed for the randomized clinical trial that oversampled African Americans.

CONCLUSION

The Risk Evaluation and Education for Alzheimer Disease study provides an instructive example of a process to develop risk assessment protocols that are sensitive to the implications of genetic testing for multiple ethnic groups with differing levels of risk.

Self-rated cardiovascular risk and 15-year cardiovascular mortality

PURPOSE

Many individuals perceive their cardiovascular disease (CVD) risk to be lower than established clinical tools would estimate, yet little is known about the long-term consequences of holding such optimistic beliefs. We evaluated whether lower self-ratings of CVD risk are associated with lower rates of CVD death after addressing potential confounding by an extensive set of social and biologic CVD risk factors.

METHODS

We conducted a 15-year mortality surveillance study of adults aged 35 to 75 years from southeastern New England (n = 2,816) who had no history of myocardial infarction. Baseline evaluation in 1990-1992 included household interview, anthropomorphic measures, and laboratory analyses. Outcomes were obtained using the National Death Index records through December 2005.

RESULTS

Rating oneself to be at lower-than-average risk for one's age and sex was associated with lower rates of CVD mortality among men (hazard ratio [HR]=0.3; 95% confidence interval [CI], 0.2-0.7) but not among women (HR = 0.9; 95% CI, 0.5-1.7). None of the following weakened the findings among men: adjustment for baseline Framingham Risk Score, propensity score adjustment for both social and biologic factors, and censoring the first 2 years of surveillance.

CONCLUSIONS

Lower self-ratings of CVD risk are independently associated with lower rates of CVD death among men.

Health behavior changes after genetic risk assessment for Alzheimer disease: The REVEAL Study

Risk information for Alzheimer disease (AD) may be communicated through susceptibility gene disclosure, even though this is not currently in clinical use. The REVEAL Study is the first randomized clinical trial of risk assessment for AD with apolipoprotein E (APOE) genotype and numerical risk estimate disclosure. We examined whether APOE genotype and numerical risk disclosure to asymptomatic individuals at high risk for AD alters health behaviors. One hundred sixty-two participants were randomized to either intervention (APOE disclosure) or control (no genotype disclosure) groups. Subjects in both groups received numerical lifetime risk estimates of future AD development based on sex and family history of AD. The intervention group received their APOE genotype. Subjects were informed that no proven preventive measures for AD existed and given an information sheet on preventative therapies under investigation. Participants who learned they were epsilon 4 positive were significantly more likely than epsilon 4 negative participants to report AD-specific health behavior change 1 year after disclosure (adjusted odds ratio: 2.73; 95% confidence interval: 1.14, 6.54; P=0.02). Post hoc analyses revealed similar significant associations between numerical lifetime risk estimates and self-report of AD-specific health behavior change. Despite lack of preventive measures for AD, knowledge of APOE genotype, numerical lifetime risk, or both, influences health behavior.

Communicating the results of clinical research to participants: attitudes, practices, and future directions

The authors discuss the available data on the effects of communicating aggregate and individual research results on participants, investigators, and the research enterprise.

Apolipoprotein E epsilon4 magnifies lifestyle risks for dementia: a population-based study

The risk of dementia and Alzheimer's disease (AD) probably results from an interaction between genetic and environmental factors. The aim of this study was to investigate the effects and putative interactions between the apoE epsilon4 allele and lifestyle related risk factors for dementia and AD. Participants of the Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study were derived from random, population-based samples previously studied in 1972, 1977, 1982 or 1987. After an average follow-up of 21 years, 1449 individuals (72.5%) aged 65-79 years were re-examined in 1998. The apoE epsilon4 allele was an independent risk factor for dementia/AD even after adjustments for sociodemographic, lifestyle and vascular factors (odds ratio [OR]=2.83, 95% confidence interval [CI]=1.61-4.97). Physical inactivity, alcohol drinking and smoking increased the risk of dementia/AD particularly among the apoE epsilon4 carriers. Furthermore, low-moderate intake of polyunsaturated, and moderate-high intake of saturated fats were associated with an increased risk of dementia/AD more pronouncedly among apoE epsilon4 carriers. Composite effect of the lifestyle factors was particularly seen among the epsilon4 carriers (OR=11.42, 95% CI=1.94-67.07 in the 4th quartile). Physical inactivity, dietary fat intake, alcohol drinking and smoking at midlife are associated with the risk of dementia and AD, especially among the apoE epsilon4 carriers. The apoE epsilon4 carriers may be more vulnerable to environmental factors, and thus, lifestyle interventions may greatly modify dementia risk particularly among the genetically susceptible individuals.

Should individuals be informed about their salt sensitivity status? First indications of the value of testing for genetic predisposition to low-risk conditions

The present study examined the possible pathways of effect of genetic testing for relatively "low-risk" conditions by exploring positive as well as negative effects of anticipated test results on the intention to restrict salt intake. In a cross-sectional within-subjects design, patients being tested for genetic predispositions to salt sensitivity reported higher overall intentions to restrict their salt intake when anticipating positive test results, confirming the value of genetic testing for low-risk conditions. However, participants in the precontemplation and preparation stages of change reported lower intentions when anticipating negative test results. This result suggests that negative test results have a negative impact on the motivation to perform preventive behavior among those who have not yet considered, and those who are planning to perform, the preventive behavior. Although the results show that, overall, genetic testing for low-risk conditions has a positive impact on the motivation to engage in preventive behavior, one needs to be aware of the potential negative effect of receiving negative test results. Consequently, individuals receiving negative test results should be carefully counseled on the meaning of the results and the consequences for preventive behavior.

Recall of disclosed apolipoprotein E genotype and lifetime risk estimate for Alzheimer's disease: the REVEAL Study

PURPOSE

To determine whether individuals recall their apolipoprotein E genotype and numeric lifetime risk estimates after undergoing a risk assessment for Alzheimer's disease.

METHODS

One-hundred and four participants underwent Alzheimer's disease risk assessment that included disclosure of apolipoprotein E genotype and a numeric lifetime risk estimate.

RESULTS

At six weeks and one year post-disclosure, 59% and 48% of participants, respectively, recalled their lifetime risk estimate, and 69% and 63% recalled their apolipoprotein E genotype. Participants were more likely to remember their genotype than numeric lifetime risk estimate at one year (P < 0.05). Apolipoprotein E epsilon4-positive participants had better recall of their genotype at both time points (P < 0.05). Participants were more likely to recall whether they carried the "risk-enhancing form of apolipoprotein E" than their specific genotype (P < 0.05).

CONCLUSIONS

These data suggest that apolipoprotein E genotype, especially the presence of an epsilon4 allele, is more memorable than a numeric risk estimate for Alzheimer's disease. Participants recalled genotype information in a more simplified, binary form. Health professionals testing for complex disorders such as Alzheimer's disease must find an appropriate balance between communicating risk in an understandable format and addressing the probabilistic nature of the information.

Genetic susceptibility testing for Alzheimer disease: motivation to obtain information and control as precursors to coping with increased risk

OBJECTIVE

This study investigated appraisals, including motivation, and coping preferences for undergoing Apolipoprotein E (APOE) susceptibility testing for Alzheimer disease (AD).

METHODS

Participants were 60 adult children of individuals affected with AD enrolled in a trial investigating use and impact of APOE susceptibility testing. An exploratory qualitative study was undertaken in which participants were interviewed about their testing experience.

RESULTS

Most participants viewed genetic testing as providing valuable information that could help direct future health care decisions and meet their emotional concerns about living at increased risk. Participants related their motivation for genetic testing to their worries about developing AD, preference to seek information about health threats, and need to feel in control of their health.

CONCLUSION

Even without prevention or treatment options, genetic testing may be a useful coping strategy for some at-risk individuals.

PRACTICE IMPLICATIONS

Once testing becomes clinically available, practitioners need to address the value and limitations of testing as well as appraisals and efforts to cope.

The post-Human Genome Project mindset: race, reliability, and health care

The following essay reports on the first session of a 2-day workshop on genetic diversity and science communication, organized by the Institute of Genetics. I argue that the four talks in this session reflected two different facets of a 'post-Human Genome Project (HGP)' view of human genetics. The first is characterized by an increasing interest in genetic differences. Two speakers - Troy Duster and Jasber Singh - expressed skepticism about one aspect of this trend: an emphasis on race in medicine and genetics. The other two speakers - Kenneth Weiss and Gustavo Turecki - spoke to a second facet of the post-HGP view: a recognition of the difficulty in translating genetic discovery into medical or public health applications. Though both sets of talks were highly critical of current trends in genetic research, they pulled in opposite directions: one warned about the role of genetics in stabilizing racial categories, while the other lamented the failure of any genetic claims or categories to stabilize at all. I argue that the use of racial categories in medicine seems likely to encounter scientific, medical, and social challenges.

Genetic risk assessment for adult children of people with Alzheimer's disease: the Risk Evaluation and Education for Alzheimer's Disease (REVEAL) study

As genetic risk factors continue to be identified for common, complex adult-onset diseases, it will become increasingly important to understand if, how, and when to translate these discoveries into clinical practice. This article provides an overview of and results to date from the REVEAL study, a multisite randomized clinical trial (n = 162) examining the impact of a genetic risk assessment program, including apolipoprotein E genotype disclosure, for adult children of people with Alzheimer's disease. The study's rationale and procedures are described, including the generation of numerical lifetime risk curves for use in the education and counseling protocol. Findings are summarized across numerous study questions, including (1) who seeks genetic risk assessment and why, (2) how apolipoprotein E results affect risk perceptions, (3) the psychological impact of genetic risk assessment, and (4) how risk information affects participants' subsequent health and insurance behaviors.