Peer Influence on Physicians in Adopting Opportunistic Salpingectomy at the Time of Hysterectomy.

BACKGROUND Since professional societies recommended counseling patients about opportunistic salpingectomy (OS) for ovarian cancer risk reduction, use of OS has increased overall. However, physicians varied in their adoption of this new cancer prevention strategy. OBJECTIVES To examine peer influence among physicians as one possible factor affecting their adoption of OS at the time of hysterectomy. STUDY DESIGN Using insurance claims data across the U.S. from the Blue Cross Blue Shield Axis database, we identified female patients age 18-49 who underwent an inpatient hysterectomy in 2019-2022. Outcome of interest was OS, defined as complete removal of both (or the remaining) fallopian tubes without concurrent removal of the ovaries. We identified peer relationships among physicians based on whether two physicians billed for at least two of the same patients among insurance claims in 2017-2018. Then for each index physician performing inpatient hysterectomy in the 2019-2022 sample, we measured the rate of OS among inpatient hysterectomies performed by all of their peer physicians in 2017-2018 (baseline). A multivariable regression analysis was used to examine whether an index physician's baseline exposure to peer physicians' OS rate was associated with the subsequent use of OS among their own patients in 2019-2022. RESULTS Among 3,373 patients who underwent inpatient hysterectomy in 2019-2022 (operated on by 1,528 index physicians), 1,871 (55.5%) received OS. The rate of OS was higher among patients whose index physician had exposure to peer physicians with the highest or second highest quartile of baseline OS rate (64.5% and 59.6%, respectively), compared to those with peer physicians in the lowest quartile of baseline OS rate (44.0%) (P<0.001). After adjusting for surgical indication, surgical route, and other patient/physician characteristics, having peer physicians in the highest and second highest quartile of baseline OS rate was associated with a 1.99 (95% CI 1.46-2.71) times and 1.64 (95% CI 1.21-2.22) times higher odds of receiving OS respectively. CONCLUSIONS Sharing patients with other physicians who had high utilization of OS was associated with an increased likelihood of an index physician subsequently using OS at the time of hysterectomy. Future efforts to promote OS use may explore the potential benefit of strategies leveraging physician peer influence.