Incidence and risk factors of new persistent opioid use after surgery and trauma: A systematic review.

Background: Persistent opioid use (POU) can occur with opioid use after surgery or trauma. Current systematic reviews include patients with previous exposure to opioids, meaning their findings may not be relevant to patients who are opioid naïve (i.e. Most recent exposure was from surgery or trauma). The aim of this review was to synthesise narratively the evidence relating to the incidence of, and risk factors for POU in opioid-naïve surgical or trauma patients.

Method: Structured searches of Embase, Medline, CINAHL, Web of Science, and Scopus were conducted, with final search performed on the 17th of July 2023. Searches were limited to human participants to identify studies that assessed POU following hospital admission due to surgery or trauma. Search terms relating to 'opioid', 'analgesics', 'surgery', 'injury', 'trauma' and 'opioid-related disorder' were combined. The Newcastle-Ottawa Scale for cohort studies was used to assess the risk of bias for studies.

Results: In total, 22 studies (20 surgical and two trauma) were included in the analysis. Of these, 20 studies were conducted in the United States (US). The incidence of POU for surgical patients 18 and over ranged between 3.9% to 14.0%, and for those under 18, the incidence was 2.0%. In trauma studies, the incidence was 8.1% to 10.5% among patients 18 and over. Significant risk factors identified across surgical and trauma studies in opioid-naïve patients were: higher comorbidity burden, having pre-existing mental health or chronic pain disorders, increased length of hospital stay during the surgery/trauma event, or increased doses of opioid exposure after the surgical or trauma event. Significant heterogeneity of study design precluded meta-analysis.

Conclusion: The quality of the studies was generally of good quality; however, most studies were of US origin and used medico-administrative data. Several risk factors for POU were consistently and independently associated with increased odds of POU, primarily for surgical patients. Awareness of these risk factors may help prescribers recognise the risk of POU after surgery or trauma, when considering continuing opioids after hospitalisation. The review found gaps in the literature on trauma patients, which represents an opportunity for future research.

Trial registration: PROSPERO registration: CRD42023397186.