Association Between Preoperative Benzodiazepine Use and Postoperative Opioid Use and Health Care Costs

Importance The association between preoperative benzodiazepine use and long-term postoperative outcomes is not well understood. Objective To characterize the association between preoperative benzodiazepine use and postoperative opioid use and health care costs. Design, Setting, and Participants In this cohort study, retrospective analysis of private health insurance claims data on 946x202f;561 opioid-naive patients (no opioid prescriptions filled in the year before surgery) throughout the US was conducted. Patients underwent 1 of 11 common surgical procedures between January 1, 2004, and December 31, 2016; data analysis was performed January 9, 2020. Exposures Benzodiazepine use, defined as long term (>= 10 prescriptions filled or >= 120 days supplied in the year before surgery) or intermittent (any use not meeting the criteria for long term). Main Outcomes and Measures The primary outcome was opioid use 91 to 365 days after surgery. Secondary outcomes included opioid use 0 to 90 days after surgery and health care costs 0 to 30 days after surgery. Results In this sample of 946x202f;561 patients, the mean age was 59.8 years (range, 18-89 years); 615x202f;065 were women (65.0%). Of these, 23x202f;484 patients (2.5%) met the criteria for long-term preoperative benzodiazepine use and 47x202f;669 patients (5.0%) met the criteria for intermittent use. After adjusting for confounders, long-term (odds ratio [OR], 1.59; 95% CI, 1.54-1.65; P < .001) and intermittent (OR, 1.47; 95% CI, 1.44-1.51; P < .001) benzodiazepine use were associated with an increased probability of any opioid use during postoperative days 91 to 365. For patients who used opioids in postoperative days 91 to 365, long-term benzodiazepine use was associated with a 44% increase in opioid dose (additional 0.6 mean daily morphine milligram equivalents [MMEs]; 95% CI, 0.3-0.8 MMEs; P < .001), although intermittent benzodiazepine use was not significantly different (0.0 average daily MMEs; 95% CI, -0.2 to 0.2 MMEs; P = .65). Preoperative benzodiazepine use was also associated with increased opioid use in postoperative days 0 to 90 for both long-term (32% increase, additional 1.9 average daily MMEs; 95% CI, 1.6-2.1 MMEs; P < .001) and intermittent (9% increase, additional 0.5 average daily MMEs; 95% CI, 0.4-0.6 MMEs; P < .001) users. Intermittent benzodiazepine use was associated with an increase in 30-day health care costs ($1155; 95% CI, $938-$1372; P < .001), while no significant difference was observed for long-term benzodiazepine use. Conclusions and Relevance The findings of this study suggest that, among opioid-naive patients, preoperative benzodiazepine use may be associated with an increased risk of developing long-term opioid use and increased opioid dosages postoperatively, and also may be associated with increased health care costs. This cohort study analyzes the preoperative use of benzodiazepines compared with long-term postoperative use of opioids and association with health care costs. Question Is preoperative benzodiazepine use associated with increased postoperative opioid use and health care costs for opioid-naive patients undergoing surgery? Findings In this US national cohort study of 945x202f;561 opioid-naive patients undergoing 1 of 11 surgical procedures, an increased risk for long-term opioid use postoperatively was noted in patients with both long-term and intermittent preoperative benzodiazepine use compared with benzodiazepine-naive patients. Some associations between preoperative benzodiazepine use and increased postoperative opioid dosages and health care costs were also observed. Meaning The findings of this study suggest that, among opioid-naive patients undergoing surgery, preoperative benzodiazepine use may increase the risk of postoperative long-term opioid use and may increase health care costs.