Warfarin is associated with the risk of vascular calcification in abdominal aorta in hemodialysis patients: a multicenter case-control study

Vascular calcifications (VCs), recognized risk factor for increased mortality, are highly prevalent in hemodialysis (HD) patients. We aimed to investigate the relation between VC and warfarin use with plain radiography. VCs were assessed using Adragao (radial and digital) and Kauppila (aortic) scores in 76 HD patients from six centers. Out of a total 711 HD patients, there were 32 (4.5%) who had been treated with warfarin for at least 1 year, and we included 44 control patients. Of the patients, 47% were females, the mean age was 66 ± 9 years, 23% were diabetics, the mean dialysis vintage was 68 ± 38 months. In warfarin group, median Kauppila score was higher than in control group [11 vs 6.5, (25%-75% percentile, 5 vs. 15), p = 0.032] and the percentage of the patients with a Kauppila score of >6 was higher, as well (76.6% vs. 50%; p = 0.029). Median Adragao score was not significantly different between the two groups [7 vs. 6, (%25,%75 percentile 6 vs. 8), p = 0.17]. Logistic regression analysis revealed that warfarin treatment was independently associated with Kauppila scores of >6 (OR 3.60, 95% CI 1.18-10.9, p = 0.024). In this study, we found that warfarin is associated to vascular calcifications, especially in aorta of HD patients.