Utility Assessments of Opioid Treatment for Chronic Pain

MEDTAP International Inc., Bethesda, Maryland; and § Pain Management Unit, Flinders Medical Centre, South Australia Objective. The primary study objective was to assess preferences for pain treatment outcomes among patients with cancer and noncancer chronic pain. A secondary objective was to assess their quality of life. Methods. Patients with cancer or noncancer chronic pain completed an interview using a computer to estimate utilities, or preference ratings, for health states related to pain treatment. The interview was devised using conjoint analysis methodology. Health states were characterized by four attributes (ef- fectiveness of pain control, side effects, side effect severity, and opioid route of administration) and their levels, and each was assumed to last for a 14-day period. Participants also completed health- related quality of life and demographic questionnaires. Results. Mean preference ratings for participants with noncancer chronic pain (N � 96) ranged from a high of 0.87 (well-controlled pain with no side effects) to a low of 0.18 (poorly controlled pain with severe mood changes/alterations, severe respiratory depression, or severe vomiting). Mean preference ratings for participants with cancer pain (N � 25) were similar and ranged from a high of 0.89 (well- controlled pain with no side effects) to a low of 0.19 (poorly controlled pain with severe respiratory depression or severe vomiting). Results confirmed previous findings that chronic pain has a severe, multidimensional impact on patients, and that the quality of life of persons with chronic pain is among the lowest observed for any medical condition. Conclusions. This study provides a valuable assessment, from the patient's perspective, of the balance between treatment tolerability and manifestation of disease symptoms. Heightened awareness of pa- tients' preferences for treatment outcomes may lead to improved selection of treatments, better ad- herence, and ultimate treatment success.