Role of Hemostatic Factors on the Risk of Venous Thrombosis in Persons with Impaired Kidney Function
Background—Factors explaining the association between impaired kidney function and venous thrombosis have not been identified so far. The aim of our study was to determine whether the association between impaired kidney function and venous thrombosis can be explained by the concurrent presence of genetic or acquired venous thrombosis risk factors.
Methods and Results—The glomerular filtration rate was estimated (eGFR) in 2473 venous thrombosis patients and 2936 controls from a population-based case-control study. Kidney function was grouped into 6 categories based on percentiles of the eGFR in the controls (>50th percentile [reference], 10th-50th percentile, 5th-10th percentile, 2.5th-5th percentile, 1st-2.5th percentile, and <1st percentile). Several hemostatic factors showed a procoagulant shift with decreasing kidney function in controls, most notably factor VIII and von Willebrand factor (VWF). As compared with eGFR> 50th percentile, factor VIII levels (adjusted mean difference of 60 IU/dl for the <1st eGFR percentile category) and VWF levels (adjusted mean difference of 60 IU/dl for the <1st eGFR percentile category) increased with each percentile category. The ORs for venous thrombosis similarly increased across the categories from 1.1 (95%CI,0.9-1.3) for the 10th-50th percentile to 3.7 (95%CI,2.4-5.7) for the <1st percentile category. Adjustment for factor VIII or von Willebrand factor attenuated these ORs indicating an effect of eGFR on thrombosis through these factors. Adjustments for other risk factors for venous thrombosis did not affect the ORs.
Conclusions—Impaired kidney function affects venous thrombosis risk via concurrently raised factor VIII and von Willebrand factor levels.
- Received March 4, 2013.
- Revision received October 21, 2013.
- Accepted October 24, 2013.