Biochemical and radiological factors affecting arterio-venous fistula maturation and its comparative outcome between adult and elderly chronic kidney disease patients.

Abstract

Background: Changing vascular integrity with aging may be a crucial factor presuming Arterio-Venous fistula (AVF) maturation. Present study compared outcome of AVF maturation and associated factors responsible between adult and elderly population.

Methodology: In this prospective observational study, CKD 4/5 patients of age ⩾18 years in whom AVF was planned were included. All were divided as adult (18-59 years) and elderly (⩾60 years) groups. Various clinical, biochemical, and radiological parameters including doppler assisted vascular mapping were recorded. AVF was created by side to side anastomosis. Clinical and doppler assessment like blood flow and wall shear stress (WSS) were done at 4th, 6th, and 12th weeks. Radiological maturation of AVF was defined as combination of blood flow of ⩾500 mL/min and vessel diameter of 5 mm. At 12 weeks, maturation of both group and association of biochemical factors with primary AVF failure were compared.

Results: A total of 120 patients (60 in each age group) were included. Overall AVF maturation rate was 75% (n = 90). Among elderly 70% (n = 42) and adult 80% (n = 48); p < 0.02. Early clinical and radiological maturation were seen in adult as compared to elderly (p = 0.022). Hyperphosphatemia, and higher c-reactive protein (CRP) levels were associated with AVF primary failure (p = 0.033) and (p = 0.005) respectively which are more in elderly group. Elderly patients had more arterial calcification (p = 0.034). Radio cephalic AVF (RCAVF) was common in both group, adult (85%) and elderly (76.5%), however elderly have more brachiocephalic AVF (BCAVF) (14.8% vs 23.3%). Blood flow, fistula diameter, and WSS had significant differences between the matured and non-matured groups (p < 0.001) in both adult and elderly.

Conclusion: Higher serum phosphate level, CRP, arterial calcification, and higher WSS were likely cause of reduced AVF maturation rate in elderly. Meticulous clinical, biochemical, and radiological evaluation, site of AVF creation selection are essential to reduce AVF failure rate.