April 13, 2015
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- In order to determine the association of opioid use with heat pain perception, investigators evaluated 187 adults with chronic pain and found that those receiving opioids were more likely to be hyperalgesic than those who were not.
- Findings suggest that hyperalgesia is independently associated with long-term opioid use.
Abstract
The hyperalgesic effects of long-term opioid use in community-dwelling adults with chronic pain have not been widely reported. Therefore, the primary aim of this study was to determine the associations between opioid use and heat pain (HP) perception in a sample of community-dwelling adults with chronic pain. The study cohort involved 187 adults (85 opioid, 102 nonopioid) with chronic pain consecutively admitted to an outpatient interdisciplinary pain treatment program. HP pain perception was assessed using a validated quantitative sensory test method of levels. An effect of opioid use was observed for nonstandardized (P=.004) and standardized (P=.005) values of HP 5-0.5 where values of the opioid group were lower (more hyperalgesic) compared to the nonopioid group. HP 5-0.5 is a measure of the slope of the line connecting HP 0.5 (HP threshold) and HP 5 (intermediate measure of HP tolerance). In univariable (P=.019) and multiple variable (P=.003) linear regression analyses (adjusted for age, sex, BMI, work status, pain diagnosis, pain severity, depression, and pain catastrophizing), opioid use was associated with lower (more hyperalgesic) nonstandardized values of HP 5-0.5. Similarly, in univariable (P=.004) and multiple variable (P=.011) linear regression analyses (adjusted for work status, pain diagnosis, pain severity, depression, and pain catastrophizing), opioid use was associated with lower standardized values of HP 5-0.5. In this sample of community-dwelling adults, these observations suggest long-term opioid use was associated with hyperalgesia independent of other clinical factors known to influence HP perception.