Incidence and risk factors for acute kidney injury in patients with excessive anticoagulation on warfarin: a retrospective study

Abstract

Anticoagulant-related nephropathy is an acute kidney injury (AKI) associated with excessive anticoagulation. The nature of the association between excessive anticoagulation with warfarin and AKI and its incidence remain unclear. To evaluate the incidence of AKI in excessively anticoagulated patients taking warfarin and examine potential risk factors. A retrospective chart review was performed in patients on chronic warfarin. The primary outcome was AKI, defined as an acute increase in creatinine of > 26.5 µmol/L within 7-14 days of an international normalized ratio (INR) ≥ 4.0. 292 patients with an INR ≥ 4.0 were included. 101 patients had CKD and 191 did not have CKD. Of the 292 patients with an INR ≥ 4.0, 38 (13%) had an AKI. In univariable analyses, CKD [odds ratio (OR) 2.1, 95% confidence interval (CI) 0.99-4.43] and use of renin-angiotensin system (RAS) blockers and/or diuretics (OR 3.85; 95% CI 1.15-20.15) were significantly associated with the risk of AKI. In a binomial logistic regression model, use of RAS blockers and/or diuretics was the only significant predictor of AKI (OR 3.4; 95% CI 1.02-11.76). Use of RAS blockers and/or diuretics significantly increased the risk of AKI in patients with warfarin-related excessive anticoagulation. Further prospective studies examining the association of high INRs and AKI are needed.

Thromboembolic and Bleeding Risk in Atrial Fibrillation Patients with Chronic Kidney Disease: Role of Anticoagulation Therapy

“…Since 2009, several studies have confirmed the hypothesis proposed by Brodsky that excessive anticoagulation is associated with WRN [56][57][58][59]. Golbin et al described the largest biopsy-proven case series of AKI induced by other VKAs, specifically the first cases of AKI by fluindione and acenocoumarol [60].…”

Role of direct oral anticoagulants in patients with kidney disease

“…118 Although not initially widely accepted, the association between anticoagulation and AKI has been confirmed in several additional studies and may be more common than initially thought. [119][120][121] For example, in 1 retrospective nonbiopsy study, 20.5% of patients treated with warfarin with a first INR of >3 developed AKI within 1 week; those with AKI had a 65% increased risk of mortality within 1 year. 122 Risk factors for anticoagulant-related nephropathy include CKD, older age, diabetes mellitus, hypertension, and cardiovascular disease.…”

Anticoagulant-Related Nephropathy in Kidney Biopsy: A Single-Center Report of 41 Cases

“…Accordingly, the term "anticoagulant-related nephropathy" (ARN) is preferred. Since the seminal report of pathologic features of warfarin-related nephropathy, 1 several investigators published case reports and retrospective studies showing AKI in association with different anticoagulants, including multiple case reports and case series that describe warfarin-related nephropathy, [7][8][9][10][11][12] case reports of dabigatran-associated AKI, [13][14][15][16][17] a case report of AKI in a patient with thrombocytopenia, 18 and a case of biopsy-proven ARN in a patient receiving antiplatelet medications. 19 Given the existing data for this newly described entity and the presence of multiple causes for anticoagulation, we explored our database of existing kidney biopsies since our initial description of ARN to describe ARN with additional details, including agents that may predispose to this unusual cause of AKI.…”

“…Accordingly, the term “anticoagulant-related nephropathy” (ARN) is preferred. Since the seminal report of pathologic features of warfarin-related nephropathy, 1 several investigators published case reports and retrospective studies showing AKI in association with different anticoagulants, including multiple case reports and case series that describe warfarin-related nephropathy, 7 , 8 , 9 , 10 , 11 , 12 case reports of dabigatran-associated AKI, 13 , 14 , 15 , 16 , 17 a case report of AKI in a patient with thrombocytopenia, 18 and a case of biopsy-proven ARN in a patient receiving antiplatelet medications. 19…”