Plasminogen activator inhibitor-1 (PAI-1) is an important inhibitor of plasminogen activator, but the role of the PAI-1 4G/5G polymorphism in deep vein thrombosis (DVT) has been contradictory. In this study, we investigated the distribution of the PAI-1 4G/5G genotype in Chinese patients with DVT compared to healthy controls and the association between the PAI-1 4G/5G genotype and the persistence of residual venous occlusion after different treatments.
The PAI-1 4G/5G genotype was determined by fluorescence in situ hybridization in 108 patients with unprovoked DVT and 108 healthy controls. The patients with DVT were treated with catheter-based therapy or anticoagulation only. Residual venous occlusion was assessed by duplex sonography during the follow-up.
Thirty-two patients (29.6%) were homozygous for 4G (4G/4G), 62 patients (57.4%) were heterozygous for 4G/5G, and 14 patients (13%) were homozygous for 5G (5G/5G). No significant difference in genotype frequency was found between DVT patients and controls. A total of 86 patients completed follow-up of ultrasound examination with a mean follow-up of 13.4 ±7.2 months. The results of patients with RVO were significantly different between homozygous 4G carriers (76.9%), heterozygous 4G/5G (58.3%), and homozygous carriers of 5G (33.3%) (p <0.05) at the end of follow-up. Catheter-based therapy showed a better result in patients who were noncarriers of 4G (p=0.045).
The PAI-1 4G/5G genotype was not a relevant predictor for DVT in Chinese patients but is a risk factor for persistent residual venous occlusion after idiopathic DVT.

Copyright © 2023. Published by Elsevier Inc.