Patients' Preferences for the Treatment of Metastatic Castrate-resistant Prostate Cancer: A Discrete Choice Experiment.

PURPOSE: Patient treatment preferences are increasingly being used to inform health care decision making. This discrete choice experiment assessed how men perceive the risks and benefits of hypothetical treatment options for metastatic castrate-resistant prostate cancer (mCRPC).

METHODS: Treatment attributes for inclusion were identified through a review of the literature and product labels. Expert interviews confirmed clinical appropriateness and patient relevance of the attributes, which included effectiveness (delay in months before chemotherapy), steroid use, possible drug interactions (additional hospital visits for monitoring), fogginess (effects on cognition and memory), fatigue (extreme tiredness), food restrictions, and bone pain. Following a pilot, the final discrete choice experiment included 18 choice sets presenting treatments for mCRPC and was completed by men with mCRPC in France, Germany, and the United Kingdom. Data were analyzed using a conditional logit model, with odds ratios (ORs) used to indicate preference for attributes, and tradeoff measures (TOM) were estimated using the ratio of coefficients.

FINDINGS: Within each attribute category and with all other factors being equal, participants (N = 285) indicated a strong preference for treatments that fully control bone pain (OR = 12.069 [95% CI, 10.555-13.800]) and for treatments that delay chemotherapy (OR, 1.727 [95% CI, 1.548-1.927]). They also preferred treatments that were associated with the lowest risk of fogginess (OR, 2.115 [95% CI, 1.849-2.420]), a lower risk of fatigue (OR, 1.365 [95% CI 1.219-1.528]), and fewer additional hospital visits (OR, 1.245 [95% CI 1.111-1.397]) than the respective reference categories. Participants preferred to use steroids under advice from a physician (OR, 1.275 [95% CI 1.132-1.437]). Food restrictions related to taking medication were not a significant concern for participants. TOM results indicated that large tradeoffs in effectiveness, fogginess, and fatigue are required for patients to prefer a treatment with uncontrolled bone pain that is very difficult to live with.

IMPLICATIONS: Men with mCRPC consider a wide range of factors when making decisions regarding their treatment. They showed a strong preference for treatment associated with better control of bone pain. They also placed value on treatments that could delay the need for chemotherapy, and they preferred to avoid side effects such as cognition and memory loss, and extreme tiredness. TOMs highlighted the importance of symptom control, even compared with potential side effects. An understanding of the degree to which patients value the attributes associated with various treatment options will assist clinicians and health care professionals when making decisions regarding the management of men with mCRPC.