Psychosocial predictors of genetic testing uptake in a cluster-randomised non-inferiority trial of telephone counselling

Abstract

Introduction: Telephone counseling (TC) increases access without conferring psychosocial risks beyond in-person genetic counseling (IPC), but genetic testing rates are lower. We evaluated predictors of genetic testing among geographically dispersed women at high risk of hereditary breast and ovarian cancer (HBOC) who completed TC or IPC. Methods: A population cancer registry approach identified 877 women aged 28-74 with breast or ovarian cancer who were randomly assigned by family to IPC or TC. Demographic and cancer-specific factors were assessed at baseline and counseling variables were assessed 1-week following counseling. Multivariable logistic regression with clinically relevant variables as well as backward selection approach was used to identify predictors of BRCA1/2 testing 12 months following genetic counseling. Findings: Testing uptake was low (27% TC, 35% IPC). Women in the TC arm were less likely to complete testing (OR = 0.53 [95% CI: 0.37-0.75]). The odds of undergoing testing were higher for women without cost barriers (OR = 21.63, [7.69 - 60.81]) and with higher perceived HBOC risk (OR = 1.33 [1.11- 1.58]). The odds of undergoing testing were lower for women with higher decisional conflict (OR = 0.95[0.94-0.97]) and who reported more patient-centered counseling (OR = 0.44 [0.30-0.67]). No significant geographic differences were observed. Discussion: Genetic testing among women at increased risk for HBOC was low, especially those who receive TC and have low risk perceptions. Cost was as a major barrier to testing. Counseling that is perceived as more patient-centered may lead to lower uptake, supporting an informed decision-making model. (Funding: NIHR01CA129142)