opioids offer no benefit for acute back pain, study finds

In a recent study published in The Lancetresearchers performed a randomized controlled trial (RCT) in 157 primary care and emergency department (ED) sites across Australia.

This study was the first placebo-controlled trial of opioids in acute low back and neck pain.

Study: Randomized trial finds opioids relieve acute back pain no better than placebo. Image Credit: fizkes/Shutterstock.com

Background

Although several trials and systematic reviews have assessed the use of opioids in patients with acute, low back and neck pain, there is a lack of RCTs making similar assessments.

Nevertheless, the evaluation of the effectiveness of opioid therapy is important because this therapy could relieve pain for a prolonged and indefinite period in these patients.

About the study

In the present placebo-controlled trial of opioids in acute low back and neck pain, Caitlin Jones et al. recruited patients with mild to moderate low back or neck pain who remained pain free for at least one month, i.e. before their current episode of spinal pain.

The primary endpoint of this study was a measure of pain intensity six weeks after randomisation. The team randomized all participants to receive opioid therapy, i.e. extended-release oxycodone-naloxone, adjusting it every seven to 14 days.

They started on a drug dose of five mg twice a day. They titrated it to 10 mg twice daily until it reduced pain intensity to zero or one on a 10-point scale after five weeks of exposure to oxycodone when participants were been titrated > 1 week. They also provided naloxone to prevent constipation and improve blindness.

All participants received care that mimicked current primary care clinical practice.

Test results

The OPAL trial yielded two notable findings.

First, two to four weeks of opioid treatment did not improve physical function, quality of life, recovery time, or absenteeism from work (overall results) in patients with acute back and neck pain. .

Even after six weeks, opioid use offered no relief or functional improvement over placebo, with an average pain difference in the two groups of 0.53 on a 10-point scale.

The other notable finding from the OPAL trial is that 25% of participants, 48\174 and 40\172 in the opioid and placebo groups, started opioid abuse at 52 weeks.

This trial obtained consistent results in sensitivity and subgroup analyses, although data for 25% of participants were missing. Moreover, his blinding was largely successful.

Although medication adherence was imperfect, it did not vary between opioid and placebo recipients and, more importantly, the 20 to 40 mg of morphine daily, i.e. the dose of oxycodone, were adequate.

Pain following acute spinal cord injury is often chronic because it is recurrent, which may have resulted in non-response to opioid treatment.

Studies have also reported that low back pain transforms within a year into nociceptive pain, defined by impaired nociceptive processing. Thus, people with nociplastic pain syndromes, including those with chronic low back pain, also respond poorly to opioid treatment.

To measure drug abuse behavior in chronic pain patients for whom physicians prescribe opioid therapy, researchers commonly use the Current Opioid Abuse Measure (COMM).

In this study, 24/123 and 13/128 people in the opioid and placebo groups scored nine or more on the COMM, indicating that they were at high risk for opioid abuse, a remarkable finding for a low-risk group with brief exposure to opioids in the past.

COMM also studies cognitive impairment and mood liability, that is, difficulty thinking clearly and controlling anger, persisting beyond the period of opioid use. Yet the authors could not specify the number of patients at high risk for opioid abuse at 52 weeks.

Conclusion

The OPAL trial is the only RCT that for the first time raised the need to re-examine current clinical guidelines recommending opioids for patients with acute low back and neck pain for whom other pharmacological treatments have not worked. or were contraindicated.

Nevertheless, this trial showed the possibility of providing primary care for up to 67% of patients with low back or neck pain with opioid treatment.