Use and safety of heparin-free maintenance hemodialysis in the USA

Abstract

Background: Although heparin is used to anticoagulate the extracorporeal circuit for most patients on maintenance hemodialysis (HD), some patients undergo heparin-free HD. We describe the determinants of heparin-free HD and its association with adverse outcomes using data from a national dialysis provider merged with Medicare claims.

Methods: We identified patients aged ≥67 years with no recent history of warfarin use who initiated maintenance HD from 2007 to 2008. We applied the Cox regression to a propensity score-matched cohort to estimate the hazards of all-cause mortality, bleeding (gastrointestinal hemorrhage, hemorrhagic stroke, other hemorrhage), atherothrombosis (ischemic stroke, myocardial infarction) and venous thromboembolism (VTE) (deep vein thrombosis, pulmonary embolism).

Results: Among 12 468 patients, 836 (6.7%) were dialyzed heparin-free. In multivariable-adjusted analyses, a history of gastrointestinal bleeding, hemorrhagic stroke and lower hemoglobin and platelet counts were associated with higher odds of heparin-free HD. Heparin-free HD use also varied as much as 4-fold by facility region. We found no significant association of heparin-free HD with all-cause mortality [hazard ratio (HR) 1.08; 95% confidence interval (CI): 0.94-1.26], bleeding (HR 1.15; 95% CI: 0.83-1.60), atherothrombosis (HR 1.09, 95% CI: 0.90-1.31) or VTE (HR 1.23, 95% CI: 0.93-1.64) compared with HD with heparin.

Conclusions: Patient markers of increased risk of bleeding and facility region associated with heparin-free HD use. Despite the potential benefits of avoiding heparin use, heparin-free HD was not significantly associated with decreased hazards of death, bleeding or thrombosis, suggesting that it may be no safer than HD with heparin.

Keywords: anti-coagulation; gastrointestinal bleeding; hemodialysis; heparin; heparin-free.

FIGURE 1:

Study population selection from the USRDS. We selected a contemporary cohort of patients 67 years of age or older with no history of warfarin use in the past year whose primary payer was Medicare who initiated renal replacement therapy between 1 January 2007 and 31 December 2008 and underwent HD at a participating facility on Day 90 (±10 days; index date) after their first ESRD service date.

FIGURE 2:

Multivariable odds ratios and 95% CIs of receiving heparin-free maintenance HD among older incident patients, by comorbidity. X-axis is on the log scale.

FIGURE 3:

Multivariable odds ratios and 95% CIs of receiving heparin-free maintenance HD among older incident patients, by platelet count (top) and hemoglobin level (bottom). P_trend < 0.001 for both parameters.

FIGURE 4:

Multivariable odds ratios and 95% CIs of receiving heparin-free maintenance HD among older incident patients, by census division. The South Atlantic census division was selected as the reference group as it contained the most patients.