Proband-mediated interventions to increase disclosure of genetic risk in families with a BRCA or Lynch syndrome condition: a systematic review

Abstract

Interventions to assist family communication about inherited cancer risk have the potential to improve family cancer outcomes. This review aimed to evaluate the efficacy of proband-mediated interventions employed within genetics clinics to increase disclosure of genetic risk to at-risk relatives. MEDLINE, Embase, CINAHL, PubMed and PsycINFO were searched for publications between 1990–2020. The quality of studies was assessed. From 5605 records reviewed, 9 studies (4 randomised control trials and 5 cohort studies) were included involving families with BRCA1, BRCA2 and Lynch syndrome. Intervention delivery modes included genetic counselling with additional telephone or in-person follow-up, letters, videos, and decision aids. The percentages of at-risk relatives informed by the proband about their risk ranged from 54.0% to 95.5% in the intervention or family-mediated comparison group. Of those who were informed, 24.4–60.0% contacted a genetics clinic and 22.8–76.2% had genetic testing after they were counselled at a genetics clinic. Significant differences between intervention and control group were reported on all three outcomes by one study, and with relatives contacting a genetics clinic by another study. The studies suggest but do not conclusively show, that tailored genetic counselling with additional follow-up can increase both the proportion of informed relatives and relatives who contact the genetics clinic. With the increase in germline testing, interventions are required to consider the family communication process and address post-disclosure variables (e.g., relative’s perceptions, emotional reactions) through engagement with probands and relatives to maximise the public health benefit of identifying inherited cancer risk in families.

Your Family Connects: A Theory-Based Intervention to Encourage Communication about Possible Inherited Cancer Risk among Ovarian Cancer Survivors and Close Relatives

“…Interventions designed to encourage family genetic risk communication have relied, almost exclusively, on individuals with pathogenic variants as purveyors of communication flow [19,[62][63][64]. These interventions largely have shown insignificant improvements in risk awareness and genetic service uptake among the breadth of at-risk relatives [19,63].…”

“…Interventions designed to encourage family genetic risk communication have relied, almost exclusively, on individuals with pathogenic variants as purveyors of communication flow [19,[62][63][64]. These interventions largely have shown insignificant improvements in risk awareness and genetic service uptake among the breadth of at-risk relatives [19,63]. We and others have encouraged a broadened approach in which interventions consider the relational and interdependent structure of families and build "we-thinking" that views risk communication as a shared responsibility [41,64].…”

Direct letters to relatives at risk of hereditary cancer—study protocol for a multi-center randomized controlled trial of healthcare-assisted versus family-mediated risk disclosure at Swedish cancer genetics clinics (DIRECT-study)

“…The listing of ARRs will be completed during the post-test counselling session and/or complemented by a follow-up telephone call from the local genetic counsellor or the study coordinator. Detailed listing of ARRs has been an interventional component in previous studies attempting to increase proband-mediated risk disclosure to ARRs [ 17 ]. The effect of this procedure has not conclusively proven to impact on uptake, and it is not possible to distinguish the effect of detailed listing of relatives from other parts of the interventions under study.…”

Public attitudes challenge clinical practice on genetic risk disclosure in favour of healthcare-provided direct dissemination to relatives

“…Several studies have explored the barriers and facilitators of family communication, and some have also tested interventions to improve efficacy. It seems that tailored genetic counselling with additional follow-up can increase both the proportion of informed relatives and relatives who contact the genetics clinic, but the data are not conclusive [ 3 , 4 ]. However, another large meta-analysis on hereditary cancer risk disclosure shows that with family-mediated disclosure, the uptake of genetic counselling in relatives is about 35%, whereas the uptake almost doubles (63%) when using a healthcare-mediated direct contact approach [ 5 ].…”