These findings provide important insights into the selection of network members for communication about genetics and cancer risk in families diagnosed with HNPCC. This analysis expands on previous studies by directly comparing communication patterns in families with and without identified mutations. Including FDRs of index cases with HNPCC but without identified mutations provides more extensive, novel data on the communication process in families without identified mutations. Patterns of communication in families with and without identified mutations were largely congruent. Differences emerged in the breadth of communication about HNPCC, and that members of indeterminate families were more likely to tap advice givers within their family networks when sharing thoughts about risk for HNPCC.
Members of families without identified mutations talked about genetic counseling and testing with a smaller number and proportion of family network members. This has implications for the spread of genetic risk information and cancer screening recommendations in families without a molecularly confirmed diagnosis. Following recommendations for early and frequent screening is important for prevention of CRC and identification of cancer in its early stages, influencing long-term health outcomes in at-risk families. Thus, it is important for this information to reach all at-risk family members. In previous studies (Stoffel et al., 2008
), index cases with indeterminate or true negative genetic test results shared those results with a smaller percentage of second- and third-degree relatives than mutation-positive index cases. The present analysis included communication about genetic counseling and testing, not just sharing of genetic test results. FDRs of indeterminate index cases were not eligible for genetic counseling and testing through the parent study, which may have limited their discussion of these topics. Whether access to genetic counseling and testing is associated with communication about these topics should be examined in future research.
Members of families without identified mutations were also less likely to share thoughts about their risk with family network members. This is surprising, since an extensive family history of HNPCC-associated cancers contributes to thoughts about risk among members of families with indeterminate HNPCC genetic test results (Ersig, Ayres, Hadley, & Koehly, 2010
) and most families in these analyses had strong family histories of cancer, regardless of family mutation status. Unlike members of indeterminate families, members of mutation-positive families can pursue genetic testing to clarify their risk for HNPCC-associated cancers. Obtaining concrete risk information through genetic testing may facilitate sharing of this information with other family members. Being able to discuss genetic testing could also influence with whom at-risk individuals choose to share information about their risk status. Lower rates of communication in families without identified mutations could also reflect less discussion about HNPCC in general. A more in-depth analysis of the content of communication in families without identified mutations is warranted.
Respondents from indeterminate families were more likely to share thoughts about risk with network members who also provide them with advice. This could reflect the uncertainty of indeterminate genetic test results (Stoffel et al., 2008
; Wilson et al., 2004
). Ambiguous risk information could cause emotional difficulty, and respondents may seek help with decisions about how to address their risk (Koehly et al., 2003
; Shiloh, Koehly, Jenkins, Martin, & Hadley, 2008
; Vadaparampil, Wey, & Kinney, 2004
). This finding should be explored further, perhaps by asking at-risk individuals about their motivations for selecting particular communication partners.
Results from this study parallel those from earlier studies demonstrating that women, regardless of risk status, are central to genetics-focused communication in families (Koehly et al., 2009
; Koehly et al., 2003
; Patenaude et al., 2006
). In the present study, women were central to communication about genetic counseling and testing and risk for HNPCC in families with and without identified mutations. Similar findings in families without identified mutations indicate that women are kin keepers of family health information, not just genetic test results. Examining more extensive communication networks could improve our understanding of the unique role of women in the dissemination of risk information within the family system. This information may be important for extended family members, such as second and third degree relatives, who were not considered in the current report. The importance of women in disseminating risk information within the family system suggests that they may play a particularly important role in educating family members about behavioral approaches to preventing CRC or identifying it in its early stages. These women may be optimal family health educators within social network-based interventions that target these behaviors.
Kinship ties were important in respondents’ communication patterns. Respondents were more likely to talk to biological family members about genetic counseling and testing and risk for HNPCC than nonbiological kin. Interpretations of the family history of cancer, and their implications for perceptions of who within the family is at risk, could lead respondents to target biological kin when discussing genetic counseling and testing and risk for HNPCC. Family mutation status did not moderate the association between kinship and communication; however, reasons for communicating with biological family members may differ. In mutation-positive families, biological relatives may be targeted because of increased risks of carrying the mutation, and eligibility for genetic testing. In families without identified mutations, communicating with biological family members may help ensure that all at-risk individuals receive appropriate information. Family history and perceived duties and responsibilities motivated communication of genetic risk information in families at high risk for hereditary forms of CRC (McCann et al., 2009
). Comparing the motives behind communication in families with indeterminate vs. mutation-positive test results would add to our understanding of these processes.
Similar to studies of mutation-positive families, this study found that the nature of relationships is associated with communication about genetics and risk (Koehly et al., 2003
; Wilson et al., 2004
). Respondents in this study communicated with network members who provide them with different forms of social support. These measures may be proxies for relationships among family members, which were not explicitly examined in this analysis. In previous studies, at-risk individuals shared genetic risk information in a bid for emotional support (Stoffel et al., 2008
). It is possible that respondents chose to communicate with network members who had previously provided some form of support, assuming that they would provide similar support in this situation. Communicating with close network members may help achieve similar goals; working to build interpersonal ties among already close family members may facilitate coping with genetic risk information (Peterson, 2005
Respondents were also more likely to share thoughts about their risk for HNPCC with members of the same generation. This may reflect shared experiences within the family, which influence topics of discussion within families with identified HNPCC mutations (Palmquist et al., in press
). Reasons for selection of different family members were not explored in this analysis. Exploring motivations for communication with different family members would provide valuable insight into these processes, as reasons for limiting discussion with older or younger family members may be similar or different.
Findings from this study were congruent with the Family Systems Genetic Illness model (Rolland & Williams, 2005
); the social network among family members has important implications for the health status of at-risk members (Berkman et al., 2000
). Family system characteristics, including different aspects of family relationships, affected patterns of communication about genetics and risk for HNPCC. Of note were the psychosocial mechanisms that operated through the family networks, which were associated with communication about genetics and risk for HNPCC.
Additional research would provide important data on the choices behind communication processes, and the potential implications of family communication. Very little is known about perception of genetic risk information and reasons for sharing this information with particular network members. Of particular interest is what information is shared among family members, specifically, in-depth examination of the content of communication about genetics and risk. The outcome measures in this analysis focused on very broad topics. Although there were few differences in the communication patterns of members of families with and without identified mutations, there may be significant differences in the content of that communication. In addition to including families with different genetic test results, future studies could compare types of family members (e.g., index cases, children) to determine whether family role influences communication about HNPCC, and provide important insights into family relationships and interactions. Exploring the naturalistic communication of genetic information within at-risk families could provide a basis for interventions designed to take advantage of naturally occurring social networks in families at risk for hereditary conditions.
Factors limiting the generalization of these findings include the small number of participants from each family, lack of ethnic diversity, and recruitment from an existing research population. On average, 2-3 people per family participated. This resulted in incomplete network data, which do not capture the full complexity of the family structures.
Findings from this study extend our knowledge of communication in families with HNPCC to include the many families in which a causative mutation has not yet been identified. In light of these findings, genetics education and counseling should be offered to families meeting clinical and pathological criteria for HNPCC, even in the absence of an identified disease causing mutation, to facilitate communication about cancer risk and cancer screening. This study identified few differences in the communication patterns of families with and without identified HNPCC mutations, despite findings in the literature suggesting that individuals and families without identified mutations might have more difficulty understanding those results and sharing them with others (Stoffel et al., 2008
). Continued inclusion of families without identified mutations in studies of families at risk of hereditary cancer syndromes will improve our understanding of communication and dissemination of risk information.