Long-term postoperative opioid prescription after cholecystectomy or gastric by-pass surgery: a retrospective observational study.

Objectives: Opioids are commonly prescribed post-surgery. We investigated the proportion of patients who were prescribed any opioids 6-12 months after two common surgeries - laparoscopic cholecystectomy and gastric by-pass (GBP) surgery. A secondary aim was to examine risk factors prior to surgery associated with the prescription of any opioids after surgery.

Methods: We performed a retrospective observational study on data from medical records from patients who underwent cholecystectomy (n=297) or GBP (n=93) in 2018 in the Region of Västerbotten, Sweden. Data on prescriptions for opioids and other drugs were collected from the patients` medical records.

Results: There were 109 patients (28%) who were prescribed opioids after discharge from surgery but only 20 patients (5%) who still received opioid prescriptions 6-12 months after surgery. All 20 of these patients had also been prescribed opioids within three months before surgery, most commonly for back and joint pain. Only 1 out of 56 patients who were prescribed opioids preoperatively due to gallbladder pain still received prescriptions for opioids 6-12 months after surgery. Although opioid use in the early postoperative period was more common among patients who underwent cholecystectomy, the patients who underwent GBP were more prone to be "long-term" users of opioids. In the patients who were prescribed opioids within three months prior to surgery, 8 out of 13 patients who underwent GBP and 12 of the 96 patients who underwent cholecystectomy were still prescribed opioids 6-12 months after surgery (OR 11.2; 95% CI 3.1-39.9, p=0,0002). Affective disorders were common among "long-term" users of opioids and prior benzodiazepine and amitriptyline use were significantly associated with "long-term" opioid use.

Conclusions: The proportion of patients that used opioids 6-12 months after cholecystectomy or GBP was low. Patients with preoperative opioid-use experienced a significantly higher risk of "long-term" opioid use when undergoing GBP compared to cholecystectomy. The indication for being prescribed opioids in the "long-term" were mostly unrelated to surgery. No patient who was naïve to opioids prior surgery was prescribed opioids 6-12 months after surgery. Although opioids are commonly prescribed in the preoperative and in the early postoperative period to patients with gallbladder disease, there is a low risk that these prescriptions will lead to long-term opioid use. The reasons for being prescribed opioids in the long-term are often due to causes not related to surgery.