The Association of Cannabis Use After Discharge From Surgery With Opioid Consumption and Patient-reported Outcomes

Abstract

Objective: To compare outcomes of patients using versus not using cannabis as a treatment for pain after discharge from surgery.

Background: Cannabis is increasingly available and is often taken by patients to relieve pain. However, it is unclear whether cannabis use for pain after surgery impacts opioid consumption and postoperative outcomes.

Methods: Using Michigan Surgical Quality Collaborative registry data at 69 hospitals, we analyzed a cohort of patients undergoing 16 procedure types between January 1, 2021, and October 31, 2021. The key exposure was cannabis use for pain after surgery. Outcomes included postdischarge opioid consumption (primary) and patient-reported outcomes of pain, satisfaction, quality of life, and regret to undergo surgery (secondary).

Results: Of 11,314 included patients (58% females, mean age: 55.1 years), 581 (5.1%) reported using cannabis to treat pain after surgery. In adjusted models, patients who used cannabis consumed an additional 1.0 (95% CI: 0.4-1.5) opioid pills after surgery. Patients who used cannabis were more likely to report moderate-to-severe surgical site pain at 1 week (adjusted odds ratio: 1.7, 95% CIL 1.4-2.1) and 1 month (adjusted odds ratio: 2.1, 95% CI: 1.7-2.7) after surgery. Patients who used cannabis were less likely to endorse high satisfaction (72.1% vs 82.6%), best quality of life (46.7% vs 63.0%), and no regret (87.6% vs 92.7%) (all P < 0.001).

Conclusions: Patient-reported cannabis use, to treat postoperative pain, was associated with increased opioid consumption after discharge from surgery that was of clinically insignificant amounts, but worse pain and other postoperative patient-reported outcomes.

Figure 1.

Opioid consumption after discharge from surgery based on postoperative cannabis use for pain among adult surgical patients in the Michigan Surgical Quality Collaborative in January-October 2022 Measures were from 30-day surveys administered after discharge from surgery through the Michigan Surgical Quality Collaborative from January 1, 2021, to October 31, 2021 among those responding to the question “What things have you done to control your pain after surgery?” Postoperative cannabis use was determined based on the response of “CBD / marijuana”. Opioid consumption was measured in oxycodone 5 mg equivalents, which is the same as oral morphine 7.5 mg. Bars signify the opioid consumption in pills based on cannabis use for pain after surgery in unadjusted (gray) and adjusted (black) models. Adjusted models incorporated age, gender, race/ethnicity, insurance, American Society of Anesthesiologists classification, body mass index, six comorbidities, surgical priority, length of stay, procedure type, prescription opioid use in the year before surgery, amount of prescription of opioids at discharge, and hospital correlation.

Figure 2.

Patient-reported pain outcomes after discharge from surgery based on postoperative cannabis use for pain among adult surgical patients in the Michigan Surgical Quality Collaborative in January-October 2022 Measures were from 30-day surveys administered after discharge from surgery through the Michigan Surgical Quality Collaborative from January 1, 2021, to October 31, 2021 among those responding to the question “What things have you done to control your pain after surgery?” Postoperative cannabis use was determined based on the response of “CBD / marijuana” Outcomes reported by patients included high pain (rating 4 to 10 on a 0 to 10 point numeric rating scale) at the site of surgery in the first week and in the first month after discharge from surgery; high satisfaction at 30 days; best quality of life at 30 days; and no regret for undergoing surgery at 30 days. Bars signify the adjusted proportion reporting an outcome based on cannabis use for pain after surgery (black) or no cannabis use (gray). Adjusted models for outcomes incorporated age, gender, race/ethnicity, insurance, American Society of Anesthesiologists classification, body mass index, six comorbidities, surgical priority, length of stay, procedure type, prescription opioid use in the year before surgery, amount of prescription of opioids at discharge, and hospital correlation.

Figure 3.

Satisfaction, quality of life, and regret after discharge from surgery based on postoperative cannabis use for pain among adult surgical patients in the Michigan Surgical Quality Collaborative in January-October 2022 Measures were from 30-day surveys administered after discharge from surgery through the Michigan Surgical Quality Collaborative from January 1, 2021, to October 31, 2021 among those responding to the question “What things have you done to control your pain after surgery?” Postoperative cannabis use was determined based on the response of “CBD / marijuana” Outcomes reported by patients included high satisfaction at 30 days; best quality of life at 30 days; and no regret for undergoing surgery at 30 days. Bars signify the adjusted proportion reporting an outcome based on cannabis use for pain after surgery (black) or no cannabis use (gray). Adjusted models for outcomes incorporated age, gender, race/ethnicity, insurance, American Society of Anesthesiologists classification, body mass index, six comorbidities, surgical priority, length of stay, procedure type, prescription opioid use in the year before surgery, amount of prescription of opioids at discharge, and hospital correlation.

Figure 4.

Postoperative cannabis use for pain by type of procedure in the Michigan Surgical Quality Collaborative Measures were from 30-day surveys administered after discharge from surgery through the Michigan Surgical Quality Collaborative from January 1, 2021, to October 31, 2021 among those responding to the question “What things have you done to control your pain after surgery?” (N=11,314) who indicated use of cannabis for pain after discharge as determined by selection of the response of “CBD / marijuana” (N=581). Bars signify the proportion of all patients reporting cannabis use for pain after surgery stratified by type of procedure.