PAIN+ CPN

Doctor, I have chronic pain. Are opioid medications more likely to reduce my pain than non-opioid medications?

In people with chronic back pain or hip or knee osteoarthritis pain, opioid medications were not more likely than non-opioid medications to improve function and reduce pain. People taking opioid medications were more likely to experience side effects. However, due to some problems with this study, these findings are not the final answer to this question.

What is the evidence?

SUMMARY OF FINDINGS

Opioid vs non-opioid medications for improving pain-related function and reducing pain intensity at 12 months

Outcome at

12 months

Opioid GroupNon-Opioid GroupEffect

Pain-related function

(e.g. walking, house work, sleeping)

59 out of 100 people had

moderate*  improvement

61 out of 100 people had

moderate* improvement

None**
Pain intensity

41 out of 100 people had

moderate* improvement

54 out of 100 people had

moderate* improvement

About 13 more people had moderate* improvement while taking non-opioids compared to taking opioids
Medication-related adverse effects

People in the opioid group experienced more adverse effects than people in the non-opioid group (details were not provided)

*moderate = 30% reduction in pain score

**Although the rates for the 2 groups look different, the difference may be due to chance rather than due to the treatments


What kind of study was this?

This was a randomized controlled trial performed in outpatient primary care clinics in the US.

Who? This study included 240 people (average age 58; 36% women) with moderate to severe back pain (65%) or hip or knee osteoarthritis pain (35%) despite taking medication. Pain was rated as moderate to severe based on a score that included pain intensity, interference with enjoyment of life, and inteference with general activity. Pain had to be present nearly every day for at least 6 months.

What? The study compared opioid medication with nonopioid medication on pain-related function at 12 months. Pain-related function = general activity, mood, walking ability, normal work, relations with other people, sleep, enjoyment of life. Patients and their physicians knew which study group they were assigned to, but the people analyzing the results did not know.

Opioid medications

vs

Non-opioid medications

Step 1: morphine (short-acting) OR hydrocodone/acetaminophen OR oxycodone (short-acting)

Step 2: morphine (long-acting) OR oxycodone (long-acting)

Step 3: fentanyl skin patch

People moved from one step to another if their pain wasn't improved and after discussion with a study pharmacist


Step 1: acetaminophen and nonsteroidal anti-inflammatory medications

Step 2: nortriptyline, amitriptyline, gabapentin and medications applied to the skin (e.g. capsaicin, lidocaine)

Step 3: pregabalin, duloxetine and tramadol*

People moved from one step to another if their pain wasn't improved and after discussion with a study pharmacist



*this medication is considered an opioid

Why was this research done?

Opioid medications have been prescribed by doctors to treat chronic pain for many years despite little evidence to show they work and rising evidence that they can be harmful. Researchers performed this study to find out if opioid medications were better than non-opioid medications for improving pain-related function and reducing pain intensity.

Experts have concerns about the results of this study because only low doses of opioids were used and some patients assigned to the non-opioid group took opioids when they weren’t supposed to. These problems mean a future study might find different results.

This Evidence Summary is based on the following article:

Krebs EE, Gravely A, Nugent S, et al. Effect of Opioid vs Nonopioid Medications on Pain-Related Function in Patients With Chronic Back Pain or Hip or Knee Osteoarthritis Pain: The SPACE Randomized Clinical Trial. JAMA. 2018 Mar 6;319(9):872-882. doi: 10.1001/jama.2018.0899. PubMed

Published: Wednesday, July 1, 2020
Last Updated: Thursday, July 30, 2020