This is the first study to report patterns of results communication among the recipients of genetic susceptibility testing for a common disease polymorphism. Results of this study showed that over 80% of the participants who underwent genetic testing for APOE communicated about their test results with others, most frequently to family and spouse. Furthermore, various sociodemographic and cognitive factors regarding AD were associated with communication patterns.
Comparing our findings to those from other studies suggests that genetic test recipients commonly share their results with others, regardless of whether they underwent strongly predictive genetic testing (
Smith, Lipe, & Bird, 2004) or a less predictive susceptibility testing such as
APOE ε4 genotyping. In our study, family members and spouses or significant others were more likely to be informed of the results by participants than individuals outside of the family. This may be due to the closeness of family members, as well as the participants’ efforts to prepare family members for future illness they may encounter or the potential future heritable illness among other family members (
Roberts et al., 2003). It also may reflect attempts to obtain social support to cope with the new risk information (
Petronio, 2002). Regardless of the reasons, this finding suggests that provision of susceptibility genetic testing results impacts not only test recipients but also their family members through communication. When genetic risk information is shared, family members’ perceptions about the health of the tested individual may be altered, or biological family members could become concerned about their own genetic risks (
Rolland & Williams, 2005). Future studies may consider the possible detrimental and positive effects of genetic susceptibility information on family members of test recipients.
More than one-third of the participants reported that they had shared the results with friends. In a previous study, about 20% of the communication and support networks of individuals affected by HNPCC was non-biological social ties (
Koehly et al., 2003). Having these individuals in social support networks were also found to be important to the psychological well-being of
BRCA1/2 genetic test recipients (
Koehly et al., 2008). Sharing test results with those without biological links may be an indication that participants were trying to obtain social support (
Hughes et al., 2002). Understanding the extent to which such support seeking behavior occurs and the role of results communication in psychological adaptation after disclosure can help develop strategies to facilitate well-being among test recipients.
Although studies of
BRCA1/2 testing for hereditary breast and ovarian cancer (HBOC) showed that mutation carriers were more (
Hughes et al., 2002;
Nippert & Schlegelberger, 2003;
Wagner Costalas et al., 2003) or less (
Nippert & Schlegelberger, 2003) likely to communicate results to family than those who received uninformative results, in our study, genotype was not associated with whether participants shared their test results. This distinction may reflect the difference in the predictive ability of the genetic testing for HBOC versus susceptibility testing for AD or the absence of medical interventions for AD. In our study, other factors, like gender and beliefs about the disease, played more prominent roles than genotype in whether or not participants communicated their genetic testing results.
Consistent with the finding of previous studies about communication of genetic test results for HBOC (
Patenaude et al., 2006) and Huntington disease (
Taylor, 2005), male participants were less likely to communicate their
APOE test results with family members. This suggests a gender difference in communication of genetic information within families regardless of the genetic risk levels. As expected based on a previous report that African American participants perceiving less benefits of genetic testing for AD (
Eckert et al., 2006), White participants in our study were more likely to share their results with friends than African American participants. Further research on reasons for the lower likelihood of communication among some subgroups would help future efforts to facilitate communication if that becomes desired.
Participants who received disclosure in a condensed protocol were more likely to share test results with their health professionals. The primary aim of the REVEAL II study was to assess the safety of disclosing
APOE test results in a clinically feasible protocol (condensed). This current report shows that participants may seek additional in-person encounters with health professionals to discuss their test results when results were disclosed in this manner. The growth of consumer based genetic susceptibility testing that involves results disclosure over internet or telephone, combined with the limited availability of genetic counselors suggests that many of these consumers may turn to their health professionals for additional information and assistance. However, physicians generally report feeling uncomfortable discussing topics related to genetics or possessing insufficient knowledge to do so (
Burke & Emery, 2002;
Menasha, Schechter, & Willner, 2000). This suggests need for programs to assist physicians in providing accurate information about genetic testing and risks, and in addressing psychological problems test recipients may experience.
Our results showed that optimism about the development of a cure and treatment was associated with results communication to family, spouse/partner, friends, and health-care providers, suggesting that when a cure and/or treatment for AD becomes available, test recipients may more openly discuss their own
APOE test results. Thus, genetic susceptibility information for conditions for which effective prevention and treatment strategies are available is likely to be communicated more than
APOE results. In fact, over 90% of the
BRCA1/2 test recipients who were identified as carriers shared results with their mothers (
Patenaude et al., 2006) and sisters (
Hughes et al., 2002;
Patenaude et al., 2006), as compared to 64% in our study that shared results with their family members.
The levels of perceived benefits of testing were not associated with communication outcomes. This may have been due to low variability as all participants had decided to undergo
APOE testing in this study and reported rather high levels of perceived benefits. Our findings suggest that placing more emphasis on the potential social threats associated with genetic risk information during counseling may lead to less communication. Disclosure of genetic information can potentially be harmful if the information was used to limit individuals’ ability to obtain insurance or employment (
Clayton, 2003). As part of the informed consent procedure in this study, participants were informed about the potential impact of testing result on privacy. Inclusion of a thorough discussion about this issue during genetic counseling may help recipients make more cautious decisions about whether and to whom they disclose their test results. A previous study showed that individuals who received positive
APOE result were more likely to purchase long-term care insurance (
Zick et al., 2005). Given that the Genetic Information Non-Discrimination Act does not protect against discrimination in long-term care insurance coverage, informing test recipients of this limitation seems important.
Although a previous survey of a random sample of adults in U.S. found that 86% of survey participants reported that they would trust their doctors with their genetic test results (
Genetics and Public Policy Center, 2007), only 12% in our study shared their results with health professionals. It may be that a 6-week follow-up period was not long enough for the test recipients to visit and discuss the results with their health care providers. However, this lower rate may also reflect participants’ awareness and concern about the potential privacy issue or the awareness about the limited utility in communicating the information with health care providers due to lack of preventative strategies. Issues of privacy and confidentiality are becoming even more pressing as genetic testing services are increasingly available through private companies (
Offit, 2008;
Wolfberg, 2006), as some have argued, genetic privacy is becoming increasingly difficult or impossible to guarantee (
Lunshof, Chadwick, Vorhaus, & Church, 2008).
Previous studies on strongly predictive genetic testing have identified other predictors of communicating genetic test results such as a feeling of responsibility to inform family members (
Forrest et al., 2003;
Hallowell et al., 2005), quality of interpersonal relationships (
Claes et al., 2003;
Dugan et al., 2003), and family characteristics (
Forrest et al., 2003;
Koehly et al., 2003). In addition, desire to prevent psychological distress among family members was reported as one of the barriers to family communication of
BRCA1/2 results (
Clarke et al., 2005). Because providing care to AD patients is a large part of life for families affected by this disease, a desire to prevent distress associated with an anticipated need for care may determine whether
APOE test results are shared within families. Conducting studies that explore the roles of such psychosocial factors in influencing communication of
APOE test results will enhance our understanding about the impact of genetic susceptibility testing on individuals and their families.
The survey items used in this study did not make a distinction between communicating results to biological and non-biological family members or between children and other family members. However, in other studies, results of predictive genetic testing were more likely to be communicated to first-degree relatives than to other relatives (
MacDonald et al., 2007;
Stoffel, Ford, Mercado, Punglia, Kohlmann, Conrad et al., 2008;
Tucker et al., 2006). Selective communication of results was also reported among those affected by Huntington Disease (
Hamilton et al., 2005). Future studies should investigate whether susceptibility genetic test recipients communicate results in a similar selective manner. Participants in this study indicated their perceived chances of developing AD in percentages. However, literature in health risk communication shows that people have limited ability to interpret risk estimates using proportions (
Hoffrage, Lindsey, Hertwig, & Gigerenzer, 2000) and that people frequently misunderstand numerical information (
Kahneman, Slovic, & Tversky, 1982). It has been shown that there is great variability in the way people respond to probability-based risk information (
Rothman & Kiviniemi, 1999), and little is known about how people construct their own risk estimate for developing an illness. Future studies may consider alternative ways to measure perceived risk. Finally, a majority of participants in this study were female and highly educated, limiting the generalizability of the results to a larger population who may choose to undergo
APOE testing in the future.
Conclusion
This is the first study that empirically evaluated the extent to which individuals receiving a genetic susceptibility test communicated their test results to others. The results showed that a majority of the individuals who underwent
APOE testing shared the results with others, especially with members of their families. The findings of this study provide insights into what the recipients of susceptibility genetic testing do with the information obtained, and suggest the need for additional research to further understand disclosure patterns by considering additional individual and social factors. Knowledge about the patterns of and factors associated with communication of genetic susceptibility information is likely to inform future public health practices as more genetic variants associated with common diseases becomes available (
Feero et al., 2008;
Scott et al., 2007). Conducting research on the role of communication in influencing health promoting behaviors of susceptibility genetic test recipients as well as their family members will help assess the potential utility of public health interventions using genetic risk information.