Comparative outcomes of predominant facility-level use of ferumoxytol versus other intravenous iron formulations in incident hemodialysis patients

Ferumoxytol was first approved for clinical use in 2009 solely based on data from trial comparisons with oral iron on biochemical anemia efficacy end points. To compare the rates of important patient outcomes (infection, cardiovascular events and death) between facilities predominantly using ferumoxytol versus iron sucrose (IS) or ferric gluconate (FG) in patients with end-stage renal disease (ESRD)-initiating hemodialysis (HD)

Association Between Vascular Access Type in Hemodialysis Patients and Subsequent Kidney Transplant Outcomes

Background: Type of vascular access for hemodialysis (arteriovenous fistula vs. arteriovenous graft vs. central venous catheter) is strongly associated with outcomes in patients with end-stage kidney disease undergoing hemodialysis. Whether a similar association exists with outcomes after kidney transplant is unknown. Objectives: To test for an association among types of vascular access used for hemodialysis and outcomes after kidney transplant. Study Design: Retrospective cohort study of hemodialysis patients receiving a first kidney transplant. Setting and Participants: Merged data from the US Renal Data System and the electronic health records of a large dialysis organization (2006–2011). Only patients receiving a kidney transplant after undergoing \u3e30 days of hemodialysis were included. Intervention: Hemodialysis access used during the most recent outpatient hemodialysis session prior to kidney transplant. Outcomes: Patients were followed from kidney transplant for all-cause mortality, kidney allograft loss from any cause, and allograft loss not from death. Measurements: Hazard ratio, HR, and 95% confidence intervals. Results: Among 9291 patients who underwent kidney transplantation between 2006–2011, 65.3% had an arteriovenous fistula and 20.4% had an arteriovenous graft as the primary vascular access type and 14.3% had central venous catheter. Cox proportional hazards regression models adjusted for demographic variables, comorbidities, transplant characteristics, and laboratory parameters found no associations between vascular access type and all-cause mortality (HR=1.13; 95% CI, 0.97-1.33 for arteriovenous graft; HR=1.00; 95% CI, 0.83-1.21 for central venous catheter). Similarly, arteriovenous graft and central venous catheter use were not independently associated with all-cause allograft loss compared with arteriovenous fistula use (HR=1.13; 95% CI, 1.00-1.28 for arteriovenous graft; HR=1.12, 95% CI, 0.96-1.29 for central venous catheter). Central venous catheter use was associated with a 30% higher risk of allograft loss from causes other than death compared to use of an arteriovenous fistula (HR=1.30; 95% CI, 1.06-1.57,). No such association was found for use of arteriovenous grafts (HR: 1.17; 95% CI, 0.98-1.39). Limitations: The study is based on retrospective data analysis and is susceptible to information bias and ascertainment bias related to the nature of data collection. Residual confounding could be present as well due to unmeasured confounders and imperfect variable ascertainment. Conclusions: End-stage renal disease is a public health concern that continues to increase in prevalence accompanied by a growing economic burden. Hemodialysis is the most common form of kidney replacement therapy offered to these patients prior to undergoing kidney transplant. This study identified potential associations of central venous catheter use with allograft loss from all causes other than death when compared to the arteriovenous fistulas. No association was present with the use of arteriovenous graft prior to the transplant with all–cause mortality, allograft loss from all causes as well as allograft loss from all causes other than death, compared to the arteriovenous fistula use. For the clinician, the present study does not provide convincing support for the hypothesis that type of vascular access pre-transplant is a strong determinant of post-transplant outcomes

Predialysis Nephrology Care and Incident Atrial Fibrillation in Older Patients With ESKD Initiating Dialysis

Background: Atrial fibrillation (AF) is common in patients with end-stage kidney disease (ESKD) on dialysis. Whether pre-ESKD nephrology care associates with AF is uncertain. Methods: We conducted a retrospective cohort study of older US patients (≥67 years) with Medicare A&B who initiated dialysis (1996–2013) without a prior diagnosis of AF. Patients were categorized by the duration and number of predialysis nephrology outpatient visits. Patients were followed for 1 year for a new diagnosis of AF. We used multivariable Cox proportional hazards regression while accounting for the competing risks of kidney transplantation and death. Results: We identified 316,067 patients with ESKD initiating dialysis between 1996 and 2013 who had no prior AF diagnosis. In this cohort, 66.9% had any pre-ESKD outpatient nephrology care, with the first outpatient nephrology visit before dialysis initiation occurring at ≤6 months in 17.9%, 7 to 12 months in 9.4%, and >12 months in 39.6%. Outpatient pre-ESKD nephrology care for ≤6, 7 to 12, and >12 months versus none yielded adjusted cause-specific hazard ratios (HRs) of 0.87 (95% CI: 0.84–0.89), 0.83 (95% CI: 0.81–0.86), and 0.85 (95% CI: 0.83–0.87) for incident AF, respectively. Further, having 1 to 4 pre-ESKD outpatient nephrology visits, 5 to 9 visits, and ≥10 visits versus none yielded adjusted cause-specific HRs of 0.89 (95% CI: 0.86–0.91), 0.86 (95% CI: 0.83–0.88), and 0.81 (95% CI: 0.79–0.83), respectively. Conclusions: Having any predialysis nephrology care before initiation of dialysis was associated with slightly lower adjusted rates of incident AF over the first year of dialysis. The optimal timing and intensity of nephrology care to reduce the incidence of AF and other adverse health events requires further study. Keywords: arrhythmia, ESRD, hemodialysis, outcomes, peritoneal dialysi

Comparative outcomes of predominant facility-level use of ferumoxytol versus other intravenous iron formulations in incident hemodialysis patients

BACKGROUND: Ferumoxytol was first approved for clinical use in 2009 solely based on data from trial comparisons with oral iron on biochemical anemia efficacy end points. To compare the rates of important patient outcomes (infection, cardiovascular events and death) between facilities predominantly using ferumoxytol versus iron sucrose (IS) or ferric gluconate (FG) in patients with end-stage renal disease (ESRD)-initiating hemodialysis (HD). METHODS: Using the United States Renal Data System, we identified all HD facilities that switched (almost) all patients from IS/FG to ferumoxytol (July 2009–December 2011). Each switching facility was matched with three facilities that continued IS/FG use. All incident ESRD patients subsequently initiating HD in these centers were studied and assigned their facility exposure. They were followed for all-cause mortality, cardiovascular hospitalization/death or infectious hospitalization/death. Follow-up ended at kidney transplantation, switch to peritoneal dialysis, transfer to another facility, facility switch to another iron formulation and end of database (31 December 2011). Cox proportional hazards regression was then used to estimate adjusted hazard ratios [HR (95% confidence intervals)]. RESULTS: In July 2009–December 2011, 278 HD centers switched to ferumoxytol; 265 units (95.3%) were matched with 3 units each that continued to use IS/FG. Subsequently, 14 206 patients initiated HD, 3752 (26.4%) in ferumoxytol and 10 454 (73.6%) in IS/FG centers; their characteristics were very similar. During 6433 person-years, 1929 all-cause, 726 cardiovascular and 191 infectious deaths occurred. Patients in ferumoxytol (versus IS/FG) facilities experienced similar all-cause [0.95 (0.85–1.07)], cardiovascular [0.99 (0.83–1.19)] and infectious mortality [0.88 (0.61–1.25)]. Among 5513 Medicare (Parts A + B) beneficiaries, cardiovascular events [myocardial infarction, stroke and cardiovascular death; 1.05 (0.79–1.39)] and infectious events [hospitalization/death; 0.96 (0.85–1.08)] did not differ between the iron exposure groups. CONCLUSIONS: In incident HD patients, ferumoxytol showed similar short- to mid-term safety profiles with regard to cardiovascular, infectious and mortality outcomes compared with the more commonly used intravenous iron formulations IS and FG