D‐dimer levels in maintenance hemodialysis patients: High prevalence of positive values also in the group without predisposing diseases

We aimed to estimate the prevalence of elevated D ‐dimer levels in all chronic hemodialysis patients and those without additional disease, and to identify factors associated with increased D ‐dimer. In 167 chronic hemodialysis patients from our center, D ‐dimer was measured before dialysis. The effects of age, C ‐reactive protein ( CRP ), recent acute illness, vascular access, anticoagulation type, dialysis vintage, and chronic diseases, considered to predispose for increased D ‐dimer levels, were analyzed. The median D ‐dimer in the whole group was 966 (inter‐quartile range [ IQR ] 524–1947) μg/L and was positive (>500 μg/L) in 75% of cases. D ‐dimer was positive in 91% of patients with acute illness, 76% of those with predisposing chronic diseases, but was still positive in 52% of patients without additional disease (i.e., acute illness or predisposing chronic diseases) – median D ‐dimer was 538.5 ( IQR 359–966) μg/L. D ‐dimer was correlated to patients' age, but not dialysis vintage. In univariate analysis, the D ‐dimer levels were significantly higher in patients with atrial fibrillation, ischemic heart disease, recent acute illness, increased CRP , dialyzed over a catheter, and on citrate anticoagulation. Multivariate logistic regression showed that only age >65 years (odds ratio [ OR ] 2.93), catheter ( OR 4.86), and positive CRP ( OR 4.07) were independently associated with positive D ‐dimer at 500 μg/L cut‐off, while the significance of age disappeared at 2000 μg/L cut‐off. To conclude, the high prevalence of positive D ‐dimer values even in hemodialysis patients without additional disease limits the use of D ‐dimer for exclusion of thromboembolic diseases in hemodialysis patients.