Determinants of Patency of Arteriovenous Fistula in Hemodialysis Patients

The arteriovenous fistula (AVF) is the vascular access of the first choice for hemodialysis (HD). Studies on patency of AVF and its affecting factors reveal a high risk for access failure. The aim of this study was to assess the primary and secondary AVF patency and their determinant factors. It was a retrospective, descriptive study conducted in the HD facility of the Nephrology Department in Rabta University Hospital. We included AVF created before December 2009 in end-stage renal disease (ESRD) patients. The end of the follow-up was fixed in December 2013. We included 126 AVFs created in 111 patients; 22.5% were aged >65 years, 39.6% were diabetic, 68.5% were hypertensive, and 26.1% had peripheral vascular disease. The primary patency rates were 78% at one year and 42% at five years. The secondary patency rates were 80% at one year and 69% at five years. Multivariate analysis revealed that the factors affecting the primary patency of AVF were: the use of jugular catheter for longer than three months (odds ratio (OR):1.91, P = 0.044) and a C-reactive protein >5 mg/L (OR: 1.7, P = 0.049). Aging (>65 years) (OR: 2.46, P = 0.042), referral time to a nephrologist <6 months before onset of ESRD (OR: 2.87, P = 0.015), absence of an antiplatelet therapy (OR: 4.47, P = 0.005), and serum phosphorus <45 mg/L (OR: 2.07, P = 0.045) were the significant impairing risk factors for secondary AVF patency. Our study suggests that early referral and creation of AVF and maturation before ESRD as well as its adequate monitoring are essential for maintaining patency.