Warfarin and Risk of Vascular Calcification in Dialysis Patients

Kidney Week 2020

Patients receiving maintenance hemodialysis commonly experience vascular calcifications, a recognized risk factor for increased mortality risk. Results of previous studies have demonstrated the association between warfarin, frequently prescribed among dialysis patients, and vascular calcifications. Eren Sadioglu, MD, and colleagues recently conducted a study to examine the association between vascular calcification and use of warfarin in patients on hemodialysis.

Results of the cross-sectional, observational, multicenter study were reported during a virtual poster session at ASN Kidney Week 2020. The poster was titled Warfarin Increased the Risk of Vascular Calcification in Hemodialysis Patients: A Multicenter Case-Control Study.

Vascular calcification was assessed using the Adragao calcification score (AS; pelvis and hands) and Kauppila score (KS; lateral lumbar spine) in 76 hemodialysis in patients from six centers. Of a total of 711 hemodialysis patients, 32 (4.5%) were being treated with warfarin for at least 1 year; the study also included 44 control patients with matching parameters of age, sex, and dialysis vintage. Clinical characteristics, concomitant treatments, and laboratory results were recorded; the study was designed to analyze possible risk factors related to vascular calcification.

Of the total cohort, 47% were female, mean age was 65.8 years, 23% had diabetes, mean dialysis vintage was 68.39 months, and mean Kt/V was 1.66. There were no significant differences between the warfarin group and the control group in clinical characteristics and basic laboratory results.

Median Kauppila score was higher in the warfarin group than in the control group (11 vs 6.5 [%25, %75 percentile, 5 vs 15]; P=.032). Percentages of Kauppila score >6 patients were also higher (76.6% vs 50%; P=.029). There were no significant differences in median Adragao score between the two groups (7 vs 6 [%25, %75 percentile 6 vs 8]; P=.177).

Results of logistic regression analysis demonstrated an independent association between warfarin treatment and Kauppila scores of >6 (odds ratio, 3.28; 95% confidence interval, 1.17-9.22; P=.024).

“The results of this study showed that warfarin is a strong risk factor for vascular calcifications, especially in aorta of hemodialysis patients,” the researchers said.

Source: Sadioglu E, Ustuner E, Ergun I, Ecder T, Nergizoglu, Keven K. Warfarin increases the risk of vascular calcification in haemodialysis patients: A multicenter case-control study. Abstract of a poster presented at the American Society of Nephrology virtual Kidney Week 2020 (PO1035), October 22, 2020.