Clara A. Chen

Disclosure of APOE Genotype for Risk of Alzheimer's Disease

BACKGROUND The apolipoprotein E (APOE) genotype provides information on the risk of Alzheimers 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. METHODS We randomly assigned 162 asymptomatic adults who had a parent with Alzheimers 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. RESULTS 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 nondisclosure group and a disclosure subgroup of subjects carrying the APOE epsilon4 allele (which is associated with increased risk) also revealed no significant differences. However, the epsilon4-negative subgroup had a significantly lower level of test-related distress than did the epsilon4-positive subgroup (P=0.01). Subjects with clinically meaningful changes in psychological outcomes were distributed evenly among the nondisclosure group and the epsilon4-positive and epsilon4-negative subgroups. Baseline scores for anxiety and depression were strongly associated with post-disclosure scores of these measures (P<0.001 for both comparisons). CONCLUSIONS The disclosure of APOE genotyping results to adult children of patients with Alzheimers disease did not result in significant short-term psychological risks. Test-related distress was reduced among those who learned that they were APOE epsilon4-negative. Persons with high levels of emotional distress before undergoing genetic testing were more likely to have emotional difficulties after disclosure. (ClinicalTrials.gov number, NCT00571025.)

BOSTON PATIENT NAVIGATION RESEARCH PROGRAM: The Impact of Navigation on Time to Diagnostic Resolution after Abnormal Cancer Screening

Background: There is a need for controlled studies to assess the impact of patient navigation in vulnerable cancer populations. Methods: Boston Patient Navigation Research Program conducted a quasi-experimental patient navigation intervention across six federally qualified inner-city community health centers, three assigned to a breast cancer navigation intervention and three assigned to a cervical cancer navigation intervention; each group then served as the control for the other. Eligible women had an abnormal breast or cervical cancer screening test conducted at one of the participating health centers during a baseline (2004–2005) or intervention period (2007–2008). Kaplan–Meier survival curves and proportional hazards regression examined the effect of patient navigation on time to definitive diagnosis, adjusting for covariates, clustering by clinic and differences between the baseline and intervention period. Results: We enrolled 997 subjects in the baseline period and 3,041 subjects during the intervention period, of whom 1,497 were in the navigated arm, and 1,544 in the control arm. There was a significant decrease in time to diagnosis for subjects in the navigated group compared with controls among those with a cervical screening abnormality [aHR 1.46; 95% confidence interval (CI), 1.1–1.9]; and among those with a breast cancer screening abnormality that resolved after 60 days (aHR 1.40; 95% CI, 1.1–1.9), with no differences before 60 days. Conclusions: This study documents a benefit of patient navigation on time to diagnosis among a racially/ethnically diverse inner city population. Impact: Patient navigation may address cancer health disparities by reducing time to diagnosis following an abnormal cancer-screening event. Cancer Epidemiol Biomarkers Prev; 21(10); 1645–54. ©2012 AACR.

Cherry consumption and decreased risk of recurrent gout attacks

OBJECTIVE To study the relationship between cherry intake and the risk of recurrent gout attacks among individuals with gout. METHODS We conducted a case-crossover study to examine the associations of a set of putative risk factors with recurrent gout attacks. Individuals with gout were prospectively recruited and followed up online for 1 year. Participants were asked to provide the following information regarding gout attacks: the onset date of the gout attack, symptoms and signs, medications (including antigout medications), and exposure to potential risk factors (including daily intake of cherries and cherry extract) during the 2-day period prior to the gout attack. We assessed the same exposure information over 2-day control periods. We estimated the risk of recurrent gout attacks related to cherry intake using conditional logistic regression. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. RESULTS Our study included 633 individuals with gout. Cherry intake over a 2-day period was associated with a 35% lower risk of gout attacks compared with no intake (multivariate OR 0.65 [95% CI 0.50-0.85]). Cherry extract intake showed a similar inverse association (multivariate OR 0.55 [95% CI 0.30-0.98]). The effect of cherry intake persisted across subgroups stratified by sex, obesity status, purine intake, alcohol use, diuretic use, and use of antigout medications. When cherry intake was combined with allopurinol use, the risk of gout attacks was 75% lower than during periods without either exposure (OR 0.25 [95% CI 0.15-0.42]). CONCLUSION These findings suggest that cherry intake is associated with a lower risk of gout attacks.

Purine-rich foods intake and recurrent gout attacks

Objective To examine and quantify the relation between purine intake and the risk of recurrent gout attacks among gout patients. Methods The authors conducted a case-crossover study to examine associations of a set of putative risk factors with recurrent gout attacks. Individuals with gout were prospectively recruited and followed online for 1 year. Participants were asked about the following information when experiencing a gout attack: the onset date of the gout attack, clinical symptoms and signs, medications (including antigout medications), and presence of potential risk factors (including daily intake of various purine-containing food items) during the 2-day period prior to the gout attack. The same exposure information was also assessed over 2-day control periods. Results This study included 633 participants with gout. Compared with the lowest quintile of total purine intake over a 2-day period, OR of recurrent gout attacks were 1.17, 1.38, 2.21 and 4.76, respectively, with each increasing quintile (p for trend <0.001). The corresponding OR were 1.42, 1.34, 1.77 and 2.41 for increasing quintiles of purine intake from animal sources (p for trend <0.001), and 1.12, 0.99, 1.32 and 1.39 from plant sources (p=0.04), respectively. The effect of purine intake persisted across subgroups by sex, use of alcohol, diuretics, allopurinol, NSAIDs and colchicine. Conclusions The study findings suggest that acute purine intake increases the risk of recurrent gout attacks by almost fivefold among gout patients. Avoiding or reducing amount of purine-rich foods intake, especially of animal origin, may help reduce the risk of gout attacks.

Effect of Alzheimer disease genetic risk disclosure on dietary supplement use.

BACKGROUND Genetic susceptibility testing for Alzheimer disease (AD) with APOE genotype disclosure is not recommended for clinical use but is available through direct-to-consumer (DTC) genetic testing companies. Little is known about whether APOE genotype disclosure would actually prompt changes in nutrition behaviors among at-risk individuals. OBJECTIVE We studied the effect of APOE genotype disclosure for AD risk assessment on dietary supplement use in adults with a family history of AD. DESIGN As part of a secondary analysis of data from the second Risk Evaluation and Education for Alzheimers Disease Study, we examined the effect of genotype disclosure on health-behavior changes among 272 unaffected first-degree relatives of persons with AD. RESULTS Overall, 16% of all participants reported a change in dietary supplement use after AD risk assessment. Participants who learned that they had at least one copy of the risk-increasing epsilon4 allele (epsilon4+) had 4.75 times the odds of reporting a change in dietary supplement use than did their counterparts who had an absence of the risk-increasing epsilon4 allele (epsilon4-) (95% CI: 2.23, 10.10; P < 0.0001) after adjustment for age, sex, race, baseline supplement use, randomization arm, and educational level. There were no significant differences between APOE epsilon4+ and epsilon4- participants in changes in overall diet, exercise, or medications. CONCLUSIONS In this sample of first-degree relatives receiving genetic susceptibility testing for AD, an APOE epsilon4+ genotype status was positively associated with dietary supplement use after risk disclosure. Such changes occurred despite the absence of evidence that supplement use reduces the risk of AD. Given the expansion of DTC genetic tests, this study highlights the need for future studies in disease risk communication.

Willingness to pay for genetic testing for Alzheimer's disease: a measure of personal utility.

BACKGROUND The increased availability of genetic tests for common, complex diseases, such as Alzheimers disease (AD), raises questions about what people are willing to pay for these services. METHODS We studied willingness-to-pay for genetic testing in a study of AD risk assessment that included APOE genotype disclosure among 276 first-degree relatives of persons with AD. RESULTS Seventy-one percent reported that they would ask for such testing from their doctor if it were covered by health insurance, and 60% would ask for it even if it required self-pay. Forty-one percent were willing to pay more than

Alcohol Quantity and Type on Risk of Recurrent Gout Attacks: An Internet-based Case-crossover Study

100 for testing, and more than half would have been willing to pay for the test out of pocket. Participants who learned that they were APOE ε4 positive and those who had higher education were less likely to want testing if covered by insurance, possibly to avoid discrimination. CONCLUSION This is the first report to examine willingness to pay for susceptibility genetic testing in a sample of participants who had actually undergone such testing. These findings reveal that some participants find valuable personal utility in genetic risk information even when such information does not have proven clinical utility.

Aid-assisted decision making and colorectal cancer screening: a randomized controlled trial.

OBJECTIVES Although beer and liquor have been associated with risk of incident gout, wine has not. Yet anecdotally, wine is thought to trigger gout attacks. Further, how much alcohol intake is needed to increase the risk of gout attack is not known. We examined the quantity and type of alcohol consumed on risk of recurrent gout attacks. METHODS We conducted a prospective Internet-based case-crossover study in the US among participants with gout and who had at least one attack during the 1 year of follow-up. We evaluated the association of alcohol intake over the prior 24 hours as well as the type of alcoholic beverage with risk of recurrent gout attack, adjusting for potential time-varying confounders. RESULTS This study included 724 participants with gout (78% men, mean age 54 years). There was a significant dose-response relationship between amount of alcohol consumption and risk of recurrent gout attacks (P <.001 for trend). The risk of recurrent gout attack was 1.36 (95% confidence interval [CI], 1.00-1.88) and 1.51 (95% CI, 1.09-2.09) times higher for >1-2 and >2-4 alcoholic beverages, respectively, compared with no alcohol consumption in the prior 24 hours. Consuming wine, beer, or liquor was each associated with an increased risk of gout attack. CONCLUSIONS Episodic alcohol consumption, regardless of type of alcoholic beverage, was associated with an increased risk of recurrent gout attacks, including potentially with moderate amounts. Individuals with gout should limit alcohol intake of all types to reduce the risk of recurrent gout attacks.

Consumer Perceptions of Interactions With Primary Care Providers After Direct-to-Consumer Personal Genomic Testing

BACKGROUND Shared decision making (SDM) is a widely recommended yet unproven strategy for increasing colorectal cancer (CRC) screening uptake. Previous trials of decision aids to increase SDM and CRC screening uptake have yielded mixed results. PURPOSE To assess the impact of decision aid-assisted SDM on CRC screening uptake. DESIGN RCT. SETTING/PARTICIPANTS The study was conducted at an urban, academic safety-net hospital and community health center between 2005 and 2010. Participants were asymptomatic, average-risk patients aged 50-75 years due for CRC screening. INTERVENTION Study participants (n=825) were randomized to one of two intervention arms (decision aid plus personalized risk assessment or decision aid alone) or control arm. The interventions took place just prior to a routine office visit with their primary care providers. MAIN OUTCOME MEASURES The primary outcome was completion of a CRC screening test within 12 months of the study visit. Logistic regression was used to identify predictors of test completion and mediators of the intervention effect. Analysis was completed in 2011. RESULTS Patients in the decision-aid group were more likely to complete a screening test than control patients (43.1% vs 34.8%, p=0.046) within 12 months of the study visit; conversely, test uptake for the decision aid and decision aid plus personalized risk assessment arms was similar (43.1% vs 37.1%, p=0.15). Assignment to the decision-aid arm (AOR=1.48, 95% CI=1.04, 2.10), black race (AOR=1.52, 95% CI=1.12, 2.06) and a preference for a patient-dominant decision-making approach (AOR=1.55, 95% CI=1.02, 2.35) were independent determinants of test completion. Activation of the screening discussion and enhanced screening intentions mediated the intervention effect. CONCLUSIONS Decision aid-assisted SDM has a modest impact on CRC screening uptake. A decision aid plus personalized risk assessment tool is no more effective than a decision aid alone. TRIAL REGISTRATION This study is registered at www.clinicaltrials.govNCT00251862.

Research articleAid-Assisted Decision Making and Colorectal Cancer Screening: A Randomized Controlled Trial

BACKGROUND Direct-to-consumer (DTC) personal genomic testing (PGT) allows individuals to learn about their genetic makeup without going through a physician, but some consumers share their results with their primary care provider (PCP). OBJECTIVE To describe the characteristics and perceptions of DTC PGT consumers who discuss their results with their PCP. DESIGN Longitudinal, prospective cohort study. SETTING Online survey before and 6 months after results. PARTICIPANTS DTC PGT consumers. MEASUREMENTS Consumer satisfaction with the DTC PGT experience; whether and, if so, how many results could be used to improve health; how many results were not understood; and beliefs about the PCPs understanding of genetics. Participants were asked with whom they had discussed their results. Genetic reports were linked to survey responses. RESULTS Among 1026 respondents, 63% planned to share their results with a PCP. At 6-month follow-up, 27% reported having done so, and 8% reported sharing with another health care provider only. Common reasons for not sharing results with a health care provider were that the results were not important enough (40%) or that the participant did not have time to do so (37%). Among participants who discussed results with their PCP, 35% were very satisfied with the encounter, and 18% were not at all satisfied. Frequently identified themes in participant descriptions of these encounters were actionability of the results or use in care (32%), PCP engagement or interest (25%), and lack of PCP engagement or interest (22%). LIMITATION Participants may not be representative of all DTC PGT consumers. CONCLUSION A comprehensive picture of DTC PGT consumers who shared their results with a health care provider is presented. The proportion that shares results is expected to increase with time after testing as consumers find opportunities for discussion at later appointments or if results become relevant as medical needs evolve. PRIMARY FUNDING SOURCE National Institutes of Health.