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1.  Disclosure of APOE Genotype for Risk of Alzheimer's Disease 
The New England journal of medicine  2009;361(3):245-254.
The apolipoprotein E (APOE) genotype provides information on the risk of Alzheimer's disease, but the genotyping of patients and their family members has been discouraged. We examined the effect of genotype disclosure in a prospective, randomized, controlled trial.
We randomly assigned 162 asymptomatic adults who had a parent with Alzheimer's disease to receive the results of their own APOE genotyping (disclosure group) or not to receive such results (nondisclosure group). We measured symptoms of anxiety, depression, and test-related distress 6 weeks, 6 months, and 1 year after disclosure or nondisclosure.
There were no significant differences between the two groups in changes in time-averaged measures of anxiety (4.5 in the disclosure group and 4.4 in the nondisclosure group, P = 0.84), depression (8.8 and 8.7, respectively; P = 0.98), or test-related distress (6.9 and 7.5, respectively; P=0.61). Secondary comparisons between the non-disclosure group and a disclosure subgroup of subjects carrying the APOE ε4 allele (which is associated with increased risk) also revealed no significant differences. However, the ε4-negative subgroup had a significantly lower level of test-related distress than did the ε4-positive subgroup (P=0.01). Subjects with clinically meaningful changes in psychological outcomes were distributed evenly among the nondisclosure group and the ε4-positive and ε4-negative subgroups. Baseline scores for anxiety and depression were strongly associated with post-disclosure scores of these measures (P<0.001 for both comparisons).
The disclosure of APOE genotyping results to adult children of patients with Alzheimer's disease did not result in significant short-term psychological risks. Test-related distress was reduced among those who learned that they were APOE ε4–negative. Persons with high levels of emotional distress before undergoing genetic testing were more likely to have emotional difficulties after disclosure. ( number, NCT00571025.)
PMCID: PMC2778270  PMID: 19605829
2.  “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 
This study evaluates the Alzheimer disease risk perceptions of individuals who accurately recall their genetics-based Alzheimer disease risk assessment.
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.
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 ε4 positive (P < 0.05) and to score higher on an Alzheimer disease controllability scale (P < 0.05).
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.
PMCID: PMC2921681  PMID: 20139767
risk recall; risk perception; Alzheimer disease; genetic susceptibility testing
3.  Perceptions of Familial Risk in those Seeking a Genetic Risk Assessment for Alzheimer’s Disease 
Journal of genetic counseling  2008;18(2):130-136.
Perceived risk is a complex concept that influences the genetic counseling process and can affect client coping and behavior. Although the association between family history and risk perception is well recognized in the literature, no studies have explored this relationship specifically in those seeking genetic susceptibility testing for a common chronic condition. REVEAL is a randomized trial assessing the impact of APOE disclosure and genetic risk assessment for Alzheimer’s disease (AD). Using baseline REVEAL data, we hypothesized that there would be a significant association between the degree of AD family history and risk perception of AD, and that this relationship would be stronger in those who believed that genetics is a very important AD risk factor. In our sample of 293 participants, we found that a higher self-perceived risk of AD was associated with strength of family history of AD (p<0.001), belief in genetics as an important AD risk factor (p<0.001), being female (p<0.001) and being Caucasian (p=0.02). These results are the first to demonstrate the association between family history and risk perception in persons volunteering for genetic susceptibility testing for a common complex disease.
PMCID: PMC2919070  PMID: 18949541
Risk perception; Alzheimer’s disease; APOE; Genetic susceptibility testing; Risk assessment
4.  Comparing test-specific distress of susceptibility versus deterministic genetic testing for Alzheimer’s disease 
Genetic risk for Alzheimer’s disease (AD) may be conferred by the susceptibility polymorphism apolipoprotein E (APOE), where the ε4 allele increases the risk of developing late-onset Alzheimer’s disease but is not a definitive predictor of the disease, or by autosomal dominant mutations (e.g., the presenilins), which almost inevitably result in early-onset familial Alzheimer’s disease. The purpose of this study was to compare the psychological impact of using these two different types of genetic information to disclose genetic risk for AD to family members of affected patients.
Data were compared from two separate protocols. The Risk Evaluation and Education for Alzheimer’s Disease (REVEAL) Study is a randomized, multi-site clinical trial that evaluated the impact of susceptibility testing for Alzheimer’s disease with APOE in 101 adult children of Alzheimer’s disease patients. A separate study, conducted at the University of Washington, assessed the impact of deterministic genetic testing by disclosing presenilin-1, presenilin-2, or TAU genotype to 22 individuals at risk for familial Alzheimer’s disease or frontotemporal dementia. In both protocols, participants received genetic counseling and completed the Impact of Event Scale (IES), a measure of test-specific distress. Scores were analyzed at the time point closest to one year post-disclosure at which IES data were available. The role of genetic test result (positive vs. negative) and type of genetic testing (deterministic vs. susceptibility) in predicting log-transformed IES scores was assessed with linear regression, controlling for age, gender, and time from disclosure.
Subjects from the REVEAL Study who learned that they were positive for the susceptibility gene APOE ε4+ experienced similar, low levels of test-specific distress compared to those who received positive results of deterministic testing in the University of Washington study (p= 0.78). APOE ε4+ individuals in the susceptibility protocol experienced more test-specific distress than those who tested ε4− in the same study (p= 0.04); however, among those receiving deterministic test disclosure, the subjects who received positive results did not experience significantly higher levels of distress when compared to those who received negative results (p= 0.88).
The findings of this preliminary study, with limited sample size, suggest that the test-related distress experienced by those receiving positive results for a deterministic mutation is similar to the distress experienced by those receiving positive results from genetic susceptibility testing, and that the majority of participants receiving genotype disclosure do not experience clinically significant distress as indicated by IES scores one year after learning of their test results.
PMCID: PMC2610442  PMID: 19012865
genetic susceptibility testing; deterministic testing; Alzheimer’s disease; APOE; genetic counseling
5.  Incorporating ethnicity into genetic risk assessment for Alzheimer disease: the REVEAL study experience 
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.
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.
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.
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.
PMCID: PMC2483343  PMID: 18344711
Alzheimer; ethnicity; genetics; risk; APOE
6.  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 ε4 positive were significantly more likely than ε4 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.
PMCID: PMC2483341  PMID: 18317253
Alzheimer; memory; health behavior change; risk assessment

Results 1-6 (6)