Background: Previous studies have not described the relationship between reducing radial artery diameter as well as increasing age and functional maturation of the radio-cephalic arteriovenous fistula (RCAVF) and no data identify these as linear relationship. The objective of this study was to perform trend analysis to assess these aspects.
Methods: Our retrospective cohort study enrolled and analyzed 353 follow-up cases that underwent first AVF creation. The artery and vein sizes were measured by ultrasound. We performed follow-up, a minimum of 3 months after surgery. Multivariable logistic regression analysis was used to identify independent risk factors inmaturation. Participant age was categorized into four groups (age ≤ 29, 30-49, 50-69, and 70-90 years). Radial artery diameter was categorized into four groups (≤ 1.9, >1.9 and ≤ 2.1, >2.1 and ≤ 2.4, >2.4 mm) according to median and interquartile ranges. We adjusted for confounders in four logistic models, and primary analyses were based on building ordered category models and tested P values for trends to estimate the relationship of radial artery diameter and each 20-year increase in age with risk of maturation.
Results: The mature RCAVF group included 301 cases, and the immature group included 52 cases. Radial artery diameter, age, and diabetes were independent risk factors of maturation. Odds ratios (ORs) associated with maturation reduced with increasing age, while ORs increased with increasing radial artery diameter. P values for trends(<0.05) were observed in all four models. A reduction in radial artery diameter and higher age were significantly associated with a higher incidence of immaturity after adjusting the multivariate models. The risks of immaturation were increased by more than 1.54 fold for each 20-year increase and increased by more than 1.34 fold for the smaller radial artery diameter group.
Conclusion: Our findings suggest that a significantly higher immaturity risk of RCAVF was associated with increasing age and a reduction in radial artery diameter. Our study identified a linear exposure-response relationship of age and radial artery diameter with immaturity incident. A careful selection of patients will be helpful in improving AVF functional maturation.
Keywords: Age; Functional maturation; Radial artery diameter; Radio-cephalic Arteriovenous fistula.