Patency rates of the arteriovenous fistula for hemodialysis: a systematic review and meta-analysis.

BACKGROUND: Advantages of the arteriovenous fistula (AVF), including long patency and few complications, were ascertained more than 2 decades ago and may not apply to the contemporary dialysis population.

STUDY DESIGN: Systematic review and meta-analysis. Estimates were pooled using a random-effects model and sources of heterogeneity were explored using metaregression.

SETTING & POPULATION: Patients treated with long-term hemodialysis using an AVF.

SELECTION CRITERIA FOR STUDIES: English-language studies indexed in MEDLINE between 2000 and 2012 using prospectively collected data on 100 or more AVFs.

PREDICTOR: Age, AVF location, and study location.

OUTCOMES: Outcomes of interest were primary AVF failure and primary and secondary patency at 1 and 2 years.

RESULTS: 7,011 citations were screened and 46 articles met eligibility criteria (62 unique cohorts; n = 12,383). The rate of primary failure was 23% (95% CI, 18%-28%; 37 cohorts; 7,393 AVFs). When primary failures were included, the primary patency rate was 60% (95% CI, 56%-64%; 13 studies; 21 cohorts; 4,111 AVFs) at 1 year and 51% (95% CI, 44%-58%; 7 studies; 12 cohorts; 2,694 AVFs) at 2 years. The secondary patency rate was 71% (95% CI, 64%-78%; 10 studies; 11 cohorts; 3,558 AVFs) at 1 year and 64% (95% CI, 56%-73%; 6 studies; 11 cohorts; 1,939 AVFs) at 2 years. In metaregression, there was a significant decrease in primary patency rate in studies that started recruitment in more recent years.

LIMITATIONS: Low quality of studies, variable clinical settings, and variable definitions of primary AVF failure.

CONCLUSIONS: In recent years, AVFs had a high rate of primary failure and low to moderate primary and secondary patency rates. Consideration of these outcomes is required when choosing a patient's preferred access type.