Real-world use gives fondaparinux advantage over heparin

In a real-world setting, patients with non-STEMI (NSTEMI) treated with fondaparinux had lower rates of death and major bleeding compared with low-molecular weight heparin (LMWH), according to a study published in the Feb. 17 issue of JAMA.

The study used Swedish registry data from 2006 through 2010. Karolina Szummer, MD, PhD, of the Karolinska University Hospital in Stockholm, and colleagues compared outcomes for patients with NSTEMI given either fondaparinux (Arixtra, GlaxoSmithKline) or LMWH. In a subanalysis, they compared outcomes for patients who also underwent PCI or who had varying degrees of kidney function.

Similar to the findings of OASIS-5 (Fifth Organization to Assess Strategies in Acute Ischemic Syndromes) trial, Szummer et al found that severe in-hospital bleeding rates were lower among patients given fondaparinux (1.1 percent vs. 1.8 percent). Use of fondaparinux also resulted in lower mortality rates compared with LMWH (2.7 percent vs. 4 percent). Bleeding and mortality rates stayed similar at 30 and 180 days. Odds of severe bleeding or death in the hospital on fondaparinux were 0.68 at 30 days and 0.72 at 180 days.

Stroke rates were low; the odds of a stroke with fondaparinux were 1.11 at 30 days and 0.98 at 180 days. Fondaparinux also resulted in low rates of recurrent MI at 30 days (0.94) and 180 days (0.97).

In patients with renal dysfunction, those given fondaparinux had lower rates of severe, in-hospital bleeding or death, regardless of severity. The odds of death or an in-hospital bleeding event were also lower for patients undergoing PCI who had been given fondaparinux, but were not statistically significant. For both patients undergoing PCI and those with renal dysfunction, odds of bleeding and death remained similar through 180 days.

While they noted that fewer patients received fondaparinux over the course of the study (36.4 percent vs. 63.6 percent), the use was growing. In 2006, 0.7 percent of patients received fondaparinux, while in 2010, 84.8 percent did.

These findings are consistent with prior research and back the guideline recommendations of both the European Society of Cardiology and the collaboration between the American Heart Association and American College of Cardiology.