Independent Prediction Factors for Primary Patency Loss in Arteriovenous Grafts within Six Months

Abstract

The objective of this study was to explore the association between loss of primary functional patency within 6 months of first use and demographic and clinical characteristics in patients with arteriovenous grafts (AVGs) receiving chronic hemodialysis. The knowledge and management of these characteristics will minimize the proportion of catheterdependent dialysis patients for whom AVGs are the best choice. This was a retrospective study of all chronic hemodialysis patients with AVGs followed by the Southern Alberta Renal Program from January 2005 to June 2008. Demographic and clinical variables and initial intra-access blood flow (IABF) were compared between those with and without loss of primary functional patency. To determine the contribution of independent variables to the dependant variable of loss of primary functional patency, a multivariable analysis using logistic regression was performed. The incidence of primary failure was 30% (107/359). Multivariable analysis found that low initial IABF (<650 mL/ min, odds ratio [OR] 31, P < 0.001), presence of diabetes (OR 3.5, P = 0.001), older age (>65 years OR 3.2, P< 0.001), and presence of peripheral vascular disease (OR 2.5, P< 0.005) were independently associated with loss of primary patency. AVGs are sometimes a better choice for those patients in which the time to and probability of successful fistula maturation may be a concern. Close monitoring of AVGs in patients with the identified risk factors associated with loss of primary patency may improve the life expectancy of the access.