Importance of side effects in opioid treatment: a trade-off analysis with patients and physicians.

UNLABELLED: This study examined the relative impact of pain relief and opioid side effects on patients' and physicians' preferences for medication. An Internet survey was completed by 618 patients (302 acute pain, 316 chronic pain) and 325 physicians (83 primary care, 80 pain specialists, 41 oncologists, 40 general surgeons, 40 orthopedic surgeons, 20 rheumatologists, 21 neurologists). Respondents completed an Adaptive Conjoint Analysis (ACA) exercise in which they indicated their relative preference for 20 pairs of hypothetical opioid pain medications described by varying levels of pain relief and side-effect incidence. Almost all patients (96% of chronic, 92% of acute) reported experiencing at least 1 side effect while on opioid medication, but physician-estimated incidence rates of most opioid side effects were much lower than those reported by patients. Opioid side effects, rather than pain relief, explained the majority of variance for medication preference for both patients (74% for chronic, 73% for acute) and treating physicians (73% for chronic, 74% for acute) in this exercise. Nausea and vomiting were major determinants of opioid medication preference, with each explaining as much of the variance in preference as did pain relief (21% to 25%). Nausea and vomiting were the most important side effects based on the amount of pain relief that respondents were willing to give up for reducing the incidence of side effects. The importance of side effects was confirmed in an open-ended question where 51% of patients and 58% of physicians identified side-effect reduction as an unmet need for pain medications. PERSPECTIVE: This study provided insights into patient and physician preferences of the risk and benefit balance of opioid therapy. This information could improve understanding of patient needs and facilitate the incorporation of patient preference into therapy choice.