Chronic kidney disease and venous thromboembolism: a prospective study.

BACKGROUND: The incidence of venous thromboembolism (VTE) is increased with severe kidney disease, but whether less-severe chronic kidney disease (CKD) increases the risk of VTE is less certain.

METHODS: We studied this in a prospective cohort of 10 700 whites and African Americans, aged 53-75 years, attending Visit 4 (1996-98) of the Atherosclerosis Risk in Communities Study. Estimated glomerular filtration rate (eGFR) values were estimated from prediction equations based on serum creatinine (eGFR(creat)) or cystatin C (eGFR(cys)). Normal kidney function was defined as eGFR ≥90 ml/min/1.73 m(2), mildly decreased kidney function as eGFR between 60 and 89 ml/min/1.73 m(2) and Stage 3 to 4 CKD as eGFR between 15 and 59 ml/min/1.73 m(2). VTE occurrence (n = 228) was ascertained over a median of 8.3 years.

RESULTS: For eGFR(cys), the age-, race- and sex-adjusted hazard ratios of total VTE were 1.0, 1.40 and 1.94 (P trend = 0.003) for normal kidney function, mildly impaired kidney function and Stage 3 to 4 CKD, respectively. These respective hazard ratios were moderately attenuated to 1.0, 1.26 and 1.60 (P trend = 0.04) with adjustment for hormone replacement therapy, diabetes and body mass index. Associations between CKD based on eGFR(cys) and VTE were slightly stronger for idiopathic VTE than for secondary VTE. In contrast, CKD based on eGFR(creat) was not associated with total VTE occurrence.

CONCLUSIONS: Stage 3 to 4 CKD, based on eGFR(cys) but not eGFR(creat), was associated with an approximately 1.6-fold increased risk of VTE.