Postop opioids up risks of persistent opioid use, emergency visits, readmission and all-cause mortality

A large retrospective cohort study by the University of Hong Kong (HKU) finds that postoperative prescription of opioids is associated with increased risks of new persistent opioid use, 30-day emergency department visits, 30-day readmission, and 30-day all-cause mortality.

The researchers analyzed Hospital Authority’s digital records of 438,128 opioid-naïve patients (mean age, 64.1 years) admitted to public hospitals for a surgical procedure between 1 January 2000 and 30 November 2020. Of all patients who had index surgery, 7.52 percent filled their opioid prescription at discharge, with the remainder being discharged without opioids. [Br J Anaesth 2023;131:586-597]

At a median follow-up of 1 month, the incidence of persistent opioid use was 9.49 percent in patients who were discharged with opioids and 2.96 percent in patients who were not prescribed opioids at discharge (odds ratio [OR], 2.30; 95 percent confidence interval [CI], 2.19–2.40; p<0.001). The risk of persistent opioid use was relatively higher in patients who were prescribed methadone (OR, 6.45; 95 percent CI, 5.47–7.61; p<0.001) and oxycodone (OR, 4.74; 95 percent CI, 3.78–5.95; p<0.001).

Subjects discharged with opioids had a significantly increased risk of persistent opioid use vs those without, regardless of whether their surgery was for cancer or another indication (p<0.001 for both). Consistent results were also observed in all subgroup analyses by scale of surgery, surgery type, surgery site, and year of surgery.

“To mitigate the risk of developing opioid dependence or addiction, patients may consider alternative pain management strategies such as nonopioid analgesics, physical therapy, and cognitive-behavioural therapy,” suggested Professor Brian Lang of the Department of Surgery at HKU.

Patients who were prescribed an opioid at discharge had a higher risk of 30-day emergency department visits vs those discharged without opioids (OR, 1.28; 95 percent CI, 1.23–1.33; p<0.001). This was true for patients whose surgery was related to cancer or other conditions and all opioid types except buprenorphine.

A higher risk of 30-day readmission was also observed in the overall population of patients who were prescribed an opioid at discharge vs those who were not (OR, 1.17; 95 percent CI, 1.13–1.20; p<0.001). In particular, opioid prescription at discharge was associated with an increased risk of 30-day readmission among patients who underwent noncancer surgery (OR, 1.24; 95 percent CI, 1.19–1.29; p<0.001).

Opioid prescription at discharge was also associated with an increased risk of postoperative all-cause mortality within 30 days after surgery in the overall population (OR, 1.68; 95 percent CI, 1.53–1.86; p<0.001). The association was significant for patients who were prescribed tramadol (OR, 1.73; 95 percent CI, 1.54–1.94; p<0.001), dextropropoxyphene (OR, 1.65; 95 percent CI, 1.21–2.26; p=0.002), and codeine (OR, 1.36; 95 percent CI, 1.09–1.71; p=0.007), but insignificant for methadone, oxycodone, or buprenorphine. Both patients who underwent cancer or noncancer surgery and were discharged with opioids had a higher risk of 30-day all-cause mortality than those who were discharged without opioids (p<0.001 for both). Of note, opioids at discharge increased the risk of 30-day all-cause mortality among patients undergoing nonmajor, elective, or emergency surgery (p<0.001 for all).

“Multimodal analgesia with nonopioid analgesics and regional block, with or without opioids, should be considered as alternatives for managing postoperative pain,” advised Professor Chi-Wai Cheung of the Department of Anaesthesiology at HKU.