Background: Progressive venous stenosis mediated, in part, by inflammatory cytokines is a major cause of synthetic hemodialysis graft failure. A tumor necrosis factor-alpha (TNF-alpha) gene polymorphism (G to A, position -308) has been shown to increase plasma cytokine levels and severity of diseases with an underlying inflammatory component.
Methods: We genotyped 67 patients with synthetic polytetrafluoroethylene (PTFE) grafts and examined the association of the high-(AA or GA) and low- (GG) production TNF-alpha-08 genotypes with the rate of graft failures/thrombosis and graft survival.
Results: Hemodialysis patients with the high-production TNF-alpha genotypes had a significantly increased rate of PTFE graft failure at 90 days (37.2% versus 14%) and 1 year (62.8% versus 34.4%) after graft placement compared with patients with the low-production genotype (respectively). Hemodialysis patients with the high-production TNF-alpha genotypes had significantly lower cumulative PTFE graft survival at 1 year (29.4% +/- 11.1% versus 71.2 +/- 6.8%) and 2 years (22.1% +/- 10.5% versus 48.2 +/- 8.1%) compared with patients with the low-production genotype (respectively). Patients with the A allele had approximately twice the mean thrombosis rate compared with those who had the low-production TNF-alpha genotype (3.3 +/- 0.8 versus 1.7 +/- 0.4 thromboses/patient/year, respectively; mean +/- SEM, p < .05).
Conclusions: These data suggest that the TNF-alpha -308 A allele is associated with increased PTFE graft thrombosis and failure in hemodialysis patients.