Reasons behind variation in NSTEMI bleeding rates unclear

The rate of in-hospital major bleeding events among non-ST-segment elevation myocardial infarction (NSTEMI) patients varies considerably between facilities, researchers found in a study published online March 4 in Circulation: Cardiovascular Quality and Outcomes, but the reasons behind the majority of cases remain unclear.

“Major bleeding has received increasing attention as a target for quality improvement in care of patients with acute myocardial infarction,” wrote the authors, led by Ying Xian, MD, PhD, of Duke Clinical Research Institute in Durham, N.C. They sought to identify the factors behind the considerable between-hospital variability that has been observed.

They identified major bleeding events, defined as an absolute drop in hemoglobin of 4 g/dL or more, intracranial hemorrhage, retroperitoneal bleeding or transfusion, in 99,200 NSTEMI patients from the National Cardiovascular Data Registry Acute Coronary Treatment Outcomes Network Registry-Get With the Guidelines between 2007 and 2010.

There were a total of 9,566 patients (9.6 percent) who experienced major bleeding during hospitalization. On average, the rate across hospitals was 9.4 percent, with the rates at some hospitals being more than 2.3 times higher than others. Patient variables and treatments accounted for about 30 percent of the variation, with anticoagulation and antiplatelet therapies accounting for 9.9 percent and 6.8 percent of the difference. Differences in case mix made up about 20 percent of the variation in rates.

With about 70 percent of the difference in bleeding rates unaccounted for, the authors hypothesized that the reasons could include unmeasured patient risk factors, such as gastrointestinal ulcers and fragile vasculature, and differences in the process of care.

Their findings, they argued, offer “an opportunity for observed care variation to be a tool to identify practices, which limit bleeding complications during NSTEMI care,” they wrote.