Predictors of patient preferences and treatment choices for localized prostate cancer.

BACKGROUND Little is known regarding how patients select treatment for localized prostate cancer. This study examined determinants of patients' preferences for health states related to prostate cancer, and assessed whether preferences and/or other factors predict treatment choices. METHODS A survey of 167 patients with newly diagnosed localized prostate cancer was conducted in 4 academic medical practices from 2004 to 2007. The authors assessed demographic and health factors, and used a time-tradeoff method to elicit preferences in the form of quality-adjusted life years (QALYs) regarding health states related to prostate cancer. Linear regressions identified predictors of preferences (in QALYs) for erectile dysfunction (ED), urinary incontinence, rectal/bowel symptoms, and metastatic prostate cancer. Linear probability models identified predictors of treatment choice. RESULTS Patient preferences were affected by a range of behavioral, demographic, and health factors. For example, sexually active men reported significantly lower QALYs for living with ED, and men with family members who died of cancer reported lower QALYs for metastatic disease. The strongest predictor of treatment was the type of physician seen (radiation oncology vs urology) at the time of the survey. Age and tumor grade also were found to be strongly predictive of treatment. In general, QALYs were not found to predict treatment choice. CONCLUSIONS Patient preferences, as reported in QALYs, are shaped by reasonable behavioral and demographic influences. However, actual treatment choices appear to bear little relation to these patient preferences, and instead demonstrate a strong association with clinician specialty. More attention to variation in preferences among patients, as well as the use of decision-support technologies, may enable physicians to facilitate more optimal individualized treatment choices for patients with prostate cancer.