Despite concerns surrounding the use of opioids for long-term management of chronic LBP, there remain few high-quality trials assessing their efficacy. The trials in this review, although achieving high internal validity scores, were characterized by a lack of generalizability, inadequate description of study populations, poor intention-to treat analyses, and limited interpretation of functional improvement. Based on our results, the benefits of opioids in clinical practice for the long-term management of chronic LBP remain questionable. Therefore, further high-quality studies that more closely simulate clinical practice are needed to assess the usefulness, and potential risks, of opioids for individuals with chronic LBP.
Opioid therapy for chronic noncancer back pain. A randomized prospective study.
A randomized, open, long-term, repeated-dose comparison of an anti-inflammatory drug and two opioid regimens in 36 patients with back pain.
                To examine the long-term safety and efficacy of chronic opioid therapy in a randomized trial of patients with back pain.
                All participants underwent a 4-week washout period of no opioid medication before being randomly assigned to one of three treatment regimens for 16 weeks: 1) naproxen only, 2) set-dose oxycodone, or 3) titrated-dose oxycodone and sustained-release morphine sulfate. All patients then were assigned to a titrated dose of opioids for 16 weeks and then gradually tapered off their medication for 12 weeks. Finally, all participants were monitored for a 1-month posttreatment washout period. Each patient was called once a week for a report on pain, activity, mood, medication, hours awake, and adverse effects and was monitored carefully for signs of abuse and noncompliance.
                Weekly reports during the experimental phase showed the titrated-dose group to have less pain (P < 0.001) and less emotional distress (P < 0.001) than the other two groups. Both opioid groups were significantly different from the naproxen-only group. During the titration phase, patients also reported significantly less pain and improved mood. Few differences were found in activity or hours asleep, or between average pretreatment and posttreatment phone-interview and questionnaire variables. No adverse events occurred, and only one participant showed signs of abuse behavior.
                The results suggest that opioid therapy has a positive effect on pain and mood but little effect on activity and sleep. Opioid therapy for chronic back pain was used without significant risk of abuse. However, tapered-off opioid treatment is palliative and without long-term benefit.