OBJECTIVE: Opioid tolerance is a criterion for opioid use disorder, which is currently an epidemic in the US. Individuals with open wounds are frequently administered opioids
however, the phenomenon of opioid tolerance has not been examined in the context of wounds. The purpose of this exploratory study was to compare patient/wound factors, wound microbiome and inflammatory mediators between individuals who were opioid-tolerant versus those who were not opioid-tolerant. METHOD: Patients with acute open wounds were enrolled in this cross-sectional study. All study data were collected before and during a one-time study dressing change. RESULTS: The study included a total of 385 participants. Opioid-tolerant participants were significantly younger (p<
0.0001)
had higher levels of depression (p=0.0055) and anxiety (p=0.0118)
had higher pain catastrophising scores (p=0.0035)
reported higher resting wound pain (p<
0.0001)
had a higher number of wounds of <
30 days' duration (p=0.0486)
and had wounds with lower bacterial richness (p=0.0152) than participants who were not opioid-tolerant. A backward elimination logistic regression model showed that four predictors-resting wound pain, age, bacterial richness and depression-were the most important variables in predicting opioid-tolerance status. CONCLUSION: These findings provide the first insights into the phenomenon of opioid tolerance in the context of open wounds. This study provides findings from which to guide hypothesis-driven research in the future.