Measures of Kidney Disease and the Risk of Venous Thromboembolism in the REGARDS (Reasons for Geographic and Racial Differences in Stroke) Study

Background: Kidney disease has been associated with venous thromboembolism (VTE) risk, but results conflict and there is little information regarding blacks. Study Design: Prospective cohort study. Setting & Participants: 30,239 black and white adults 45 years or older enrolled in the REGARDS (Reasons for Geographic and Racial Differences in Stroke) Study 2003 to 2007. Predictors: Estimated glomerular filtration rate (eGFR) using the combined creatinine-cystatin C (eGFR(cr-cys)) equation and urinary albumin-creatinine ratio (ACR). Outcomes: The primary outcome was adjudicated VTE, and secondary outcomes were provoked and unprovoked VTE, separately. Mortality was a competing-risk event. Results: During 4.6 years of follow-up, 239 incident VTE events occurred over 124,624 person-years. Cause-specific HRs of VTE were calculated using proportional hazards regression adjusted for age, sex, race, region of residence, and body mass index. Adjusted VTE HRs for eGFR(cr-cys) of 60 to <90, 45 to <60, and <45 versus >= 90 mL/min/1.73 m(2) were 1.28 (95% CI, 0.94-1.76), 1.30 (95% CI, 0.77-2.18), and 2.13 (95% CI, 1.21-3.76). Adjusted VTE HRs for ACR of 10 to <30, 30 to <300, and >= 300 versus <10 mg/g were 1.14 (95% CI, 0.84-1.56), 1.15 (95% CI, 0.79-1.69), and 0.64 (95% CI, 0.25-1.62). Associations were similar for provoked and unprovoked VTE. Limitations: Single measurement of eGFR and ACR may have led to misclassification. Smaller numbers of events may have limited power. Conclusions: There was an independent association of low eGFR (<45 vs >= 90 mL/min/1.73 m(2)) with VTE risk, but no association of ACR and VTE. (C) 2017 by the National Kidney Foundation, Inc.