Background: It is uncertain whether pathologically prolonged international normalized ratio (INR) seen in chronic liver disease (CLD) protects against venous thromboembolism (VTE). Previous studies reported VTE incidence of 0.5% to 1.9% in patients with CLD. We sought to evaluate VTE incidence among hospitalized patients with CLD according to INR levels.
Methods: This was a retrospective cohort study performed at a tertiary university hospital. We included all adult patients admitted with a primary diagnosis of CLD over a 7-year period. The primary outcome was the development of VTE during hospital stay. Patients were divided into quartiles according to their highest admission INR. VTE events and prophylaxis rates were compared among INR quartiles.
Results: During the allotted 7-year period, we included 190 patients. Of these, 12 developed VTE events, yielding a VTE incidence of 6.3%. There was no significant difference in the incidence of VTE between INR quartiles. Hospital mortality rates were higher in the higher INR quartiles than in the lower ones (P < .001), but hospital length of stay was not significantly different. Of the patients with documented VTE, one (4.2%) was Child-Pugh stage A, three (4.6%) were stage B, and eight (8.0%) were stage C (P = .602). VTE prophylaxis was not used in 75% of patients.
Conclusions: An elevated INR in the setting of CLD does not appear to protect against the development of hospital-acquired VTE. The notion that "auto-anticoagulation" protects against VTE is unfounded. Use of DVT prophylaxis was extremely low in this population.