Risk and complications of venous thromboembolism in dialysis patients

Background. Contemporary data on venous thromboembolism (VTE) risk in dialysis patients are limited. Our objective was to determine the risk and complications of VTE among incident maintenance dialysis patients. Methods. We performed a retrospective cohort study using administrative databases. We included adult incident dialysis patients from 2004 to 2010 (n =13 315). Dialysis patients were age- and sex-matched to individuals of the general population using a 1:4 ratio (n = 53 260). We determined the 3-year cumulative incidence and incidence rate (IR) of VTE, pulmonary embolism (PE) and deep venous thrombosis (DVT). We examined outcomes of bleeding and all-cause mortality following a VTE event among matched dialysis patients who did and did not experience a VTE. We used Cox proportional hazards regression models, stratified on matched sets, to calculate the hazard ratios (HRs) for all outcomes of interest. Results. VTE occurred in 1114 (8.4%) dialysis patients compared with 1233 (2.3%) individuals in the general population (IR 37.1 versus 8.1 per 1000 person-years; HR 4.5 [95% confidence interval (CI) 4.1-4.9]; adjusted HR 2.9 (95% CI 2.6-3.4)}. Both components of VTE [PE and DVT; adjusted HR 4.0 (95% CI 2.9-5.6) and HR 2.8 (95% CI 2.4-3.2), respectively] occurred more frequently in dialysis patients. Compared with dialysis patients without a VTE, those with a VTE had a higher risk of bleeding [adjusted HR 2.0 (95% CI 1.3-2.9)] and all-cause mortality [adjusted HR 2.4 (95% CI 2.0-2.8)]. Conclusions. VTE is common in dialysis patients and confers a high risk of major bleeding and all-cause mortality. Thromboprophylaxis and VTE treatment studies in dialysis patients are needed.