Relationship between arteriovenous fistula stenosis and neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios in hemodialysis patients.

Abstract

Introduction: Arteriovenous fistulas (AVFs) are the preferred vascular access for hemodialysis, although they can be complicated by stenosis secondary to chronic inflammatory processes. The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been proposed as accessible inflammatory markers. The objective was to evaluate their association with AVF stenosis in hemodialysis patients.

Materials and methods: A multicenter observational study was conducted on 42 incident patients with autologous or prosthetic AVFs in hemodialysis units in Quito (June 2024–October 2025). Clinical, ultrasound, and laboratory variables were collected. Stenosis was defined via Doppler ultrasound (resistance index >0.7). Descriptive analyses and multivariable logistic regression were performed.

Results: Age ranged from 33 to 77 years, and 60% were men. 91% had an autologous AVF, and 83% had a brachiocephalic AVF. Seventeen cases of stenosis (40.48%) were identified, primarily in the middle third. In the multivariate analysis, the minimum PLR showed a significant association with stenosis, whereas the NLR was not significant. Hemoglobin was independently associated with a lower risk of stenosis (OR=0.42; p=0.022). Additionally, a significant interaction was observed between diabetes and NLR (p=0.034), demonstrating that the effect of NLR varies depending on the presence of diabetes (see Table 1).

Conclusions:
AVF stenosis is primarily associated with hematological and inflammatory alterations; the PLR ​​stands out as a relevant marker, and hemoglobin as a protective factor. The NLR showed an effect dependent on the presence of diabetes. These findings suggest that inflammatory indices can serve as complementary tools in vascular access surveillance, although they are not sufficient in isolation.