(035) Risk of Post-Operative Venous Thromboembolism in Patients Undergoing Gender Affirming Surgery: An Assessment of 1,731 Patients
Authors: Hebert K , Synder L , Horns J , Das R , Downing J , Dy G , Horns J , Mccormick B , Myers J , Hotaling J 
Published: May 2023

Abstract

Introduction
Venous thromboembolism (VTE) is a source of significant morbidity and mortality in the post-operative setting. However, poor follow up and the ability for patients to present to other hospital systems for post-operative care, have made assessment of the incidence of post-operative VTE difficult. As a result, previous attempts to assess VTE risk following gender affirming surgery have been limited to small volume, single institution studies. It has been hypothesized that patients undergoing gender affirming surgery may be at increased risk of post-operative VTE given the concomitant use of hormone therapy.

Objective
To assess the risk of venous thromboembolism and associated risk factors following feminizing and masculinizing gender affirming surgery.

Methods
Using IBM MarketScan, a commercial claims database, patients undergoing feminizing and masculinizing surgery were identified using Current Procedural Terminology (CPT), ICD-9, and ICD-10 procedure codes between 2011 and 2020. ICD-9 and ICD-10 codes were used to identify healthcare visits associated with lower extremity deep vein thrombosis (DVT) and pulmonary embolism (PE) within 90-days of surgery. Covariates including diabetes, peripheral vascular disease, cardiovascular disease, hypertension, varicose veins, hypercoagulable state, smoking history, and prior VTE were assessed. Given the small cohort size of men undergoing masculinizing surgery, descriptive statistics, including the 90-day incidence, were performed. In patients undergoing feminizing surgery, descriptive and univariate statistics were performed including Kruskal-Wallis tests (continuous variables) or Chi-squared/Fischer’s exact tests (categorical variables).

Results
1,731 patients underwent feminizing surgery (1,588) or masculinizing (143) surgery between 2011 and 2020 with a median age (interquartile range) of 34 years (22, 53) and 35 years (26, 46), respectively. A history of DVT or PE events prior to gender affirming surgery was identified in 1.07% (feminizing) and 0.7% (masculinizing). DVT or PE events within 90-days following feminizing surgery and masculinizing surgery occurred in 1.07% and 0.7%, respectively. On univariable analysis, increasing age (p&lt;0.001), bladder cancer (p&lt;0.001), prior cystoprostatectomy (p=0.001), diabetes (p=0.007), cardiovascular disease (p&lt;0.001), hypertension (p=0.04), prior DVT (p&lt;0.001), and prior PE (p&lt;0.001) were associated with increased likelihood of post-operative VTE in patients undergoing feminizing gender affirming surgery.

Conclusions
In a cohort of patients undergoing gender affirming surgery, the risk of post-operative VTE was low with 1.07% (feminizing) and 0.7% (masculinizing) of patients developing a VTE event within 90 days of surgery. In patients undergoing feminizing gender affirming surgery, increasing age, bladder cancer, cystoprostatectomy, diabetes, cardiovascular disease, hypertension, prior DVT, and prior PE were associated with an increased likelihood of developing a postoperative DVT or PE.

Disclosure
Any of the authors act as a consultant, employee or shareholder of an industry for: Cooper Medical, Boston Scientific, Acerus, Coloplast, Turtle Health, Maximus, FirmTech, StreamDx, Inherent Bioscience.