Kidney Week

Abstract: PUB179

Nephrotic Syndrome-Associated Venous Thromboembolism: Patient Characteristics and Emerging Role of Factor Xa Inhibitors

Session Information

• Publication Only

Category: Glomerular Diseases

• 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics

Authors

• Palacios, Fernando, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States

Fernando Palacios, MD

• Crestani, Andre S., The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States

Andre S. Crestani, MD

• Debnath, Subrata, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States

Subrata Debnath, MBBS, PhD, MPH

• Lorenzo, Carlos, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States

Carlos Lorenzo, MD, PhD

• Nassar, Tareq Issa, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States

Tareq Issa Nassar, MD

• Kanduri, Swetha Rani, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States

Swetha Rani Kanduri, MD, MBBS, FASN

Background

Venous thromboembolism (VTE) in nephrotic syndrome (NS) carries significant morbidity, yet risk stratification beyond histology remains limited. KDIGO 2021 recommends anticoagulation in membranous nephropathy (MN) at albumin <2.5 g/dL, with no guidance for other histologies and limited data supporting the use of factor Xa inhibitors. We describe real-world VTE outcomes in patients receiving factor Xa inhibitors versus other anticoagulants.

Methods

We conducted a single-center retrospective observational study (2015-2025) of adults with biopsy-proven NS at UT Health San Antonio. Data extracted through systematic electronic medical record review. Adults ≥18 years with NS secondary to glomerulonephritis were included. Primary outcomes were imaging-confirmed VTE, VTE rates by anticoagulation strategy (none, apixaban, heparin/enoxaparin, warfarin), and by histologic subtype. Wilcoxon, Fisher exact, and Kaplan-Meier analyses were used.

Results

Twenty-nine patients were included; 58.6% were male, mean age was 47.7 years, and 55.2% were Hispanic. Hypertension was present in 51.7%. Mean baseline albumin was 1.33 g/dL, with 65% of patients having albumin ≤1.3 g/dL. Five VTE events (17.2%) occurred within 1 day to 5 months of NS diagnosis. All events occurred in patients with albumin ≤1.3 g/dL (26.3%), while no events occurred above this threshold (LR chi-square p=0.029; log-rank p=0.084).

Among 7 patients receiving apixaban prophylaxis, no VTE events occurred. In comparison, VTE occurred in 2/14 patients without anticoagulation and 2/5 patients receiving heparin/enoxaparin; 1 event occurred on warfarin (p=0.040). Patients with VTE were older (63.4 vs 44.5 years; p=0.030), had higher creatinine (3.18 vs 1.13 mg/dL; p=0.002), and lower albumin (1.47 vs 2.82 g/dL; p=0.025). Interestingly, amyloidosis had the highest VTE rate (66.7%), followed by minimal change disease (28.6%) and lupus nephritis (14.3%).

Conclusion

Severe hypoalbuminemia (≤1.3 g/dL) was the strongest predictor of VTE across histologic subtypes, suggesting risk may extend beyond current guideline thresholds. No VTE episodes occurred with prophylactic apixaban use, supporting further prospective evaluation of factor Xa inhibitors in NS-associated VTE prevention.