Daily hemodialysis has been associated with favorable surrogate markers of improved survival among hemodialysis patients. These outcomes include improvements in left ventricular mass index, chronic inflammation, nutritional markers and mineral metabolism markers.[1-5] There is currently no study that directly addresses the impact of daily dialysis on vascular access outcomes over long-term follow-up. Previous observational and uncontrolled studies of daily hemodialysis have shown mixed results in regards to vascular access outcomes with the majority showing no difference in access outcomes[5-9] and some showing a trend toward improved access outcomes.[4, 10-12] The randomized-controlled Frequent Hemodialysis Network Trial (FHN) study of daily, in-center, hemodialysis showed no significant differences in access outcomes, but a trend toward more access procedures with similar patency rates.[13] Importantly, no controlled studies have addressed this issue over a long-term follow-up of greater than 1 year.
A potential source of morbidity and possibly mortality from daily hemodialysis is vascular access failure as vascular access complications can have grave consequences;[14, 15] therefore, it is important to determine the effects of frequent cannulation on the vascular access. Arteriovenous grafts may be especially susceptible to early failure because punctures in the grafted material may weaken and eventually undermine the integrity of the access. A secondary consideration is the potential for increased medical costs if daily dialysis increases the number of access procedures necessary to maintain access patency. Patient acceptance of daily dialysis therapies may be impaired if the effects on vascular access patency are unknown because access complications are also a significant source of patient morbidity through pain associated with procedures and increased hospitalizations because of access failure. Finally, because arteriovenous fistulae are associated with improved survival in epidemiological studies,[16] failure of the arteriovenous access may lead to increased mortality rates.
This particular study aimed to investigate the impact of daily dialysis on vascular access complications. We hypothesized that frequent dialysis cannulation would be associated with either increased or similar rates of vascular access complications. To test this hypothesis we performed a nonrandomized, prospective cohort study with contemporary control of daily hemodialysis vs. conventional hemodialysis and examined vascular access outcomes. With increased adoption of daily dialysis regimens, it is important to determine the long-term effects of daily hemodialysis on access survival, because little is known regarding the potential for vascular access harm related to frequent cannulation.