Impact of self-reported race on Villalta Scale postthrombotic syndrome scores and correlation with venous disease-specific quality of life: an exploratory analysis of the Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis Trial

Background: The Villalta Scale (VS) to diagnose postthrombotic syndrome (PTS) consists of 5 patient-reported leg symptoms and 6 clinician-rated leg signs. It is unknown how the scale performs across racial groups.

Objectives: Our study explored if there were differences in VS scores, particularly clinician-rated signs components, according to self-reported race.

Methods: Exploratory analysis of the ATTRACT trial, a randomized controlled trial conducted at 56 US sites that investigated pharmacomechanical catheter-directed thrombolysis to prevent PTS after proximal deep vein thrombosis (DVT). At the 6-month visit after randomization, we compared self-reported Black (n = 123) and White (n = 541) participants for mean total VS score, VS symptoms score, VS signs score, individual signs scores, and correlation coefficients between VS signs and VS symptoms scores and between VS signs and Venous Insufficiency Epidemiological and Economic Study Quality of Life (VEINES-QOL) scores (a self-reported venous disease-specific quality of life measure).

Results: Mean total VS score (4.67 vs. 4.12, P = .54),VS signs score (1.66 vs. 2.00, P = .07), and VS symptoms score (2.83 vs. 2.04, P = .10) were similar between Black and White participants. The mean score for one individual VS sign, venous ectasia, was lower in Black vs. White participants (0.24 vs. 0.63, P< .01). There was similar, modest correlation in Black and White participants between VS signs and VS symptoms scores (r _black = 0.19; r _white = 0.23) and between VS signs and VEINES-QOL scores (r _black = -0.32; r _white = -0.30). Results were adjusted for ATTRACT trial treatment group, age, sex, body mass index, DVT extent, hypertension, diabetes, dyslipidemia, and congestive heart failure.

Conclusion: The findings suggest that some differences in VS scores exist according to self-reported race. It is unclear whether these reflect clinicians' underrating of some VS signs and/or differences in PTS severity. Further work is needed to understand how the VS performs across racial groups.