Analysis of risk factors associated with intimal hyperplasia in arteriovenous fistulas among patients undergoing hemodialysis.

Arteriovenous fistula (AVF) intimal hyperplasia (IH) is a major pathological basis of AVF stenosis and dysfunction in patients undergoing maintenance hemodialysis. This single-center retrospective observational cohort study enrolled adult hemodialysis patients with a native AVF at our institution between May 2021 and May 2023. IH was determined primarily by duplex ultrasound (DUS) evidence of pathologic venous intimal thickening and/or hemodynamically significant stenosis attributable to IH, with angiographic confirmation when clinically indicated. Demographic characteristics, hemodialysis vintage, dialysis prescription and adequacy, vascular access profiles, comorbidities, medication exposure, and routine laboratory indices were extracted from electronic medical records, the hemodialysis information platform, and the vascular access imaging database. Comparisons were performed between the IH group (n = 38) and the control group (n = 126), followed by univariate and multivariable logistic regression analyses. Patients with IH were slightly older and had longer hemodialysis vintage and a longer interval from AVF creation to evaluation. The IH group also showed higher rates of diabetes mellitus and recent infection, higher inflammatory burden reflected by C-reactive protein (CRP) and neutrophil-to-lymphocyte ratio (NLR), lower albumin, higher d-dimer, and higher serum phosphate. In multivariable analysis, longer time from AVF creation to evaluation, diabetes mellitus, higher CRP, and higher phosphate independently correlated with IH, whereas higher albumin was protective. These findings suggest that cumulative access exposure, metabolic disease, systemic inflammation, nutritional status, and disordered mineral metabolism jointly contribute to IH risk and may inform targeted surveillance and preventive management in routine hemodialysis care.