Elevated plasma gas6 levels are associated with venous thromboembolic disease.

Growth arrest-specific 6 (gas6), a novel vitamin K-dependent protein, has been demonstrated to have a role in thrombus stabilization as gas6 null mice are resistant to lethal venous and arterial thrombosis. However, the association between gas6 and venous thromboembolism has not been elucidated in humans. The present study aims to assess the role of gas6 in human venous thromboembolic (VTE) disease. Using a highly specific ELISA method, we measured plasma levels of gas6 in plasma samples obtained from 279 patients with VTE and 79 healthy volunteers. Medication history, comorbid conditions and VTE characteristics were documented. Mean gas6 levels were higher in patients with VTE as compared to healthy volunteers, being 46 ±11 ng/ml and 35 ±6.4 ng/ml respectively (P < 0.001). Odds ratios (OR) for VTE given elevated (≥90th percentile of healthy volunteers) gas6 levels were estimated in regression models in the whole study population. After adjustment for age, sex, medications and comorbidity, subjects with elevated gas6 had an increased risk of VTE (OR of 16.3 (95% CI 5.8-45.7, P < 0.001) compared to those with lower levels of gas6. This association remains significant even among patients with a comparable age distribution. Among patients with VTE, mean gas levels showed a trend of higher levels in those with more extensive thrombi. There was no correlation between elevated gas6 levels and recurrent VTE. In conclusion, we demonstrate an association between VTE and elevated gas6 levels consistent with in vivo murine models of thrombosis. This constitutes a potential novel mechanism for thrombosis in humans and may aid in the understanding of the pathophysiology of VTE.