Background: Multiple treatments with similar efficacy exist for mPC resulting in multifaceted treatment choices. Shared decision-making (SDM) engages patients and may be associated with superior outcomes in men with prostate cancer. We assessed the association of decision locus of control (DLOC) (SDM vs. physician- or patient-directed decisions) and measures of patient quality of life (QOL), including patient reported functional outcomes, and decision satisfaction. Methods: Patients completed surveys of decision-making practices after a clinic visit in which a decision occurred. Patients also completed the EORTC QLQ-C30 QOL instrument at baseline (time of decision), and 2- and 4-months. Scores for each QOL dimension and pain were calculated for each time point, and the least-squared means were compared among DLOC groups to evaluate for associations using a mixed effects model. Results: 101 patients participated, with median age of 69 years [range: 49-92]. Most patients were white (80%) and married (82%). A majority of patients reported experiencing SDM in the clinic visit assessed (63, 62%). At baseline, there was no significant difference in patient reported QOL dimensions among DLOC groups, but patients reporting physician-directed decisions reported significantly greater baseline pain than the SDM group (Table). At 4 months, patient reported physical functioning was superior among patients reporting patient-directed (p=0.005) or SDM (p=0.03) than those who reported physician-directed decision-making. There was a trend toward greater decision satisfaction among patients who reported patient-directed (p=0.06) or SDM (p=0.10) at 4-months compared to men reporting physician-directed decision-making. There were no differences at 4 months for social, emotional, cognitive, or role functioning between DLOC groups. Conclusions: Patients who reported greater control during treatment decisions had superior physical functioning and a trend toward greater decision satisfaction at 4 months compared with patients reporting physician-directed decisions, suggesting measurable domains of benefit from involvement in the decision-making process. Continued research evaluating the association between physical and psychological outcomes and DLOC is needed, including larger studies within more diverse populations.

Note: Higher score indicates higher function/satisfaction or greater pain.