Abstract CN03-01: Predictors of change in colorectal cancer screening decision stage among participants in a randomized, controlled trial of genetic and environmental risk assessment

Abstract

Abstract Purpose. This report presents findings from a randomized, controlled trial of colorectal cancer (CRC) genetic and environmental risk assessment (GERA). Predictors of positive change in CRC screening decision stage (SDS) were identified among participants who completed a baseline and follow-up survey. Methods. A total of 493 primary care patients who were 50 to 79 years of age, were eligible for CRC screening were randomized to a GERA Group (n=328) or a usual care Control Group (n=165). GERA Group participants underwent decision counseling about GERA, had a blood draw to assess CRC risk, and received risk feedback (modestly-elevated or average risk) based on the combined presence of SNPs 677C>T and/or 1298A>C of the methylenetetrahydrofolate reductase (MTHFR) gene and serum folate level. Participants received a CRC screening kit and completed a follow-up telephone survey. Univariable analyses and multivariable regression were performed to determine if baseline screening sociodemographic and lifestyle factors, knowledge, psychosocial factors, stress about CRC, SDS, and risk status predicted self-reported change in SDS. Results. Participants were: female (56%), white (61%), 50 to 59 years of age (66%), > high school education (71%), and married (55%). Overall, SDS was as follows: decided against (1%), undecided (11%), and decided to do (87%) screening. 38% of participants exhibited a positive change in SDS to a higher decision stage, including actual screening. Positive SDS change by study group was: GERA Group (39%) and Control Group (34%). Multivariable analyses for all participants showed that knowledge was a positive predictor (p=0.006) of SDS change, as were lower CRC stress and lower SDS (p=0.023 and p<0.001, respectively). 12% of GERA Group participants had an elevated risk for CRC. Positive SDS change in the GERA Group by risk status was: elevated risk (36%) and average risk (42%). In the GERA Group, knowledge was a positive, nonsignificant predictor (p=0.107) of SDS change, while lower CRC stress and lower SDS were significant positive predictors (p=0.038 and p<0.001, respectively). Conclusion. Exposure to GERA and feedback indicating modestly-elevated risk influenced change in SDS among participants who had greater knowledge about CRC screening, reported lower CRC stress, or had decided against about or were uncertain about CRC screening. Citation Format: Ronald E. Myers, Sharon Manne, Karen Ruth, James Cocroft, Randa Sifri, Barry Ziring, David Weinberg. Predictors of change in colorectal cancer screening decision stage among participants in a randomized, controlled trial of genetic and environmental risk assessment. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr CN03-01.