For workers with chronic low back pain, taking opioid pain medications can significantly improve their ability to lift and perform other work-related physical tasks, according to study published in the Journal of Pain, the publication of the American Pain Society.

A team of Canadian researchers evaluated 30 patients with chronic low back pain of more than six months duration. In the double-blinded, random-ordered, placebo-controlled trial, subjects performed a lifting test twice, once after receiving intravenous fentanyl and once after taking a placebo. The goal of the study was to examine the impact of acute opioid administration on repetitive lifting and lowering exercise in workers with low-back pain.

Low-back pain is a common cause of work absences and reduced productivity. While opioids appear to be effective for short-term pain reduction, few clinical trials have been performed to evaluate their efficacy in the workplace. Results of the Journal of Pain study showed opioids improved lifting performance between 15 percent and 48 percent. The authors conclude the performance improvement was due to reduced pain intensity. Pain reduction, as measured by pain scales, was indicative of clinically relevant analgesia achieved by the medication.

While the authors say their results are consistent with a previously published study, the controlled laboratory environment for this trial is very different from actual workplace conditions. Therefore, longer trials are needed to measure the effectiveness of opioids as an adjunct to functional restoration programs for workers with low-back pain.

In addition, another nationwide study showed that medication to treat fibromyalgia, pregabalin (Lyrica), was effective at three different dosage strengths in a sample of 750 fibromyalgia patients. All patients met diagnostic criteria for fibromyalgia set by the American College of Rheumatology. Three groups were given active dosages of 300, 450 or 600 mg twice daily for 14 weeks, and the fourth group received placebo. All patients stopped taking other medications for fibromyalgia during the trial.

Study results showed that significantly more patients in the three pregabalin groups had a 30 percent-to 50-percent decrease in pain ratings compared to patients given placebo. Unlike previous studies of the drug, this trial also addressed other aspects of fibromyalgia, such as determining efficacy for improving sleep. Sleep disturbance is major problem for a large majority of fibromyalgia patients. In all three drug treatment groups, subjects reported significant improvements in the quality of their sleep, as measured by daily sleep quality diaries.

Source: American Pain Society