Risk of Venous Thromboembolism in Patients by Albuminuria and Estimated GFR

Background: The risk for venous thromboembolism (VTE) is elevated with albuminuria or a low estimated glomerular filtration rate (eGFR). However, the VTE risk due to the combined effects of eGFR and albuminuria are unknown. Study Design: Population-based cohort study. Settings & Participants: 694,956 adults in Ontario, Canada, from 2002 to 2012. Factors: eGFR and albumin-creatinine ratio (ACR). Outcome: VTE. Results: 15,180 (2.2%) VTE events occurred during the study period. Both albuminuria and eGFR were independently associated with VTE. The association of albuminuria and VTE differed by level of eGFR (P for ACR x eGFR interaction <0.001). After considering the competing risk for death, there was a 61% higher rate of VTE in patients with normal eGFRs (eGFRs > 90 mL/min/ 1.73 m(2)) and heavy albuminuria (ACR > 300 mg/g) compared with those with normal eGFRs and no albuminuria (subdistribution HR, 1.61; 95% CI, 1.38-1.89). Among those with reduced kidney function (eGFR, 15-29 mL/min/ 1.73 m(2)), the risk for VTE was only minimally increased, irrespective of albuminuria (subdistribution HRs of 1.23 [95% CI, 1-1.5] and 1.09 [95% CI, 0.82-1.45] for ACR < 30 and >300 mg/g, respectively). Limitations: Only single determinations of ACR and eGFR were used. Diagnostic/International Classification of Diseases codes were used to define VTE. Conclusions: Albuminuria increases the risk for VTE markedly in patients with normal eGFRs compared with those with lower eGFRs. (C) 2017 by the National Kidney Foundation, Inc.