Whether a particular surgeon’s opioid prescribing behavior is associated with prolonged postoperative opioid use is unknown. We tested the hypothesis that the patients of surgeons with a higher propensity to prescribe opioids are more likely to utilize opioids long-term postoperatively.
We identified 612,378 Medicare fee-for-service patients undergoing total knee arthroplasty between January 1, 2011 and December 31, 2016. We then defined “high-intensity” surgeons as those whose patients were, on average, in the upper quartile of opioid utilization in the immediate perioperative period (preoperative day 7 to postoperative day 7), We then estimated whether patients of “high-intensity” surgeons had higher opioid utilization in the mid-term (postoperative days 8-90) and long-term (postoperative days 91-365), utilizing an instrumental variables approach to minimize confounding from unobservable factors.
In the final sample of 604,093 patients, the average age was 74 years (SD 5) and there were 413,121 (68.4%) females. 180,926 patients (30%) were treated by “high-intensity” surgeons. On average, patients receiving treatment from a “high-intensity” surgeon received 36.1 (SD 35.0) oral morphine equivalents (MME)/day during the immediate perioperative period compared to 17.3 MME (SD 23.1) per day for all other patients (+18.9 MME/day difference; 95%CI 18.7 to 19.0; p<0.001). After adjusting for confounders, receiving treatment from a “high-intensity” surgeon was associated with higher opioid utilization in the mid-term opioid postoperative period (+2.4 MME/day difference, 95%CI 1.7 to 3.2, p<0.001, [11.4 MME/day vs 9.0]), and lower opioid utilization in the long-term postoperative period (-1.0 MME/day difference, 95%CI -1.4 to -0.6, p<0.001, [2.8 MME/day vs 3.8]). While statistically significant, these differences were clinically small.
Among Medicare fee-for-service patients undergoing total knee arthroplasty, surgeon-level variation in opioid utilization in the immediate perioperative period was associated with statistically significant but clinically insignificant differences in opioid utilization in the medium- and long-term postoperative periods.