Quantifying family dissemination and identifying barriers to communication of risk information in Australian BRCA families

Purpose: Recommendations for BRCA1 and BRCA2 mutation carriers to disseminate information to at-risk relatives pose significant challenges. This study aimed to quantify family dissemination, to explain the differences between fully informed families (all relatives informed verbally or in writing) and partially informed families (at least one relative uninformed), and to identify dissemination barriers. Methods: BRCA1 and BRCA2 mutation carriers identified from four Australian hospitals (n = 671) were invited to participate in the study. Distress was measured at consent using the Kessler psychological distress scale (K10). A structured telephone interview was used to assess the informed status of relatives, geographical location of relatives, and dissemination barriers. Family dissemination was quantified, and fully versus partially informed family differences were examined. Dissemination barriers were thematically coded and counted. Results: A total of 165 families participated. Information had been disseminated to 81.1% of relatives. At least one relative had not been informed in 52.7% of families, 4.3% were first-degree relatives, 27.0% were second-degree relatives, and 62.0% were cousins. Partially informed families were significantly larger than fully informed families, had fewer relatives living in close proximity, and exhibited higher levels of distress. The most commonly recorded barrier to dissemination was loss of contact. Conclusion: Larger, geographically diverse families have greater difficulty disseminating BRCA mutation risk information to all relatives. Understanding these challenges can inform future initiatives for communication, follow-up and support.