Between 2005 and 2011, only 3.76 percent of patients received tissue plasminogen activator (tPA) treatment following acute ischemic strokes, according to a recent analysis.

However, the researchers found that patients were 11 percent more likely to receive tPA treatment during each subsequent year. They also noted that patients who were black, Hispanic, female or in the 11-state region known as the stroke belt were less likely to receive tPA.

Lead researcher Tracy Madsen, MD, of Brown University in Rhode Island, presented the results Feb. 23 at the American Stroke Association’s International Stroke Conference in Houston.

Madsen is a member of the NorthEast Cerebrovascular Consortium, an organization created in 2006 to improve stroke care in Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, New York and New Jersey.

If tPA, the only FDA-approved treatment for ischemic stroke, is administered within 4.5 hours of stroke symptom onset, it can dissolve the blood clot and restore blood flow to the brain, according to a news release.

For this study, Madsen and her colleagues examined 563,087 patients who had an acute ischemic stroke between 2005 and 2011. The median age was 74 years old, while 14.9 percent of patients were black and 53.3 percent were female.

A fully adjusted model found that patients who were black, Hispanic or female or were discharged from stroke belt states were less likely to receive intravenous tPA. The stroke belt states are Alabama, Arkansas, Georgia, Indiana, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee and Virginia.

Meanwhile, patients were more likely to receive intravenous tPA if they had private insurance or were discharged from designated stroke centers, Get With The Guidelines (GWTG) hospitals with silver or gold awards or teaching, large or urban hospitals. The American Heart Association offers GWTG programs to improve stroke, heart failure, resuscitation and atrial fibrillation care and promote adherence to guidelines for those conditions.

The analysis found that blacks were 38 percent less likely than whites to receive tPA, while Hispanics were 25 percent less likely than whites to receive tPA. In addition, women were 6 percent less likely than men to receive tPA, people with private insurance were 29 percent more likely to receive tPA than those with Medicare and residents of the stroke belt states were 31 percent less likely to receive tPA compared with residents of other states.

“Some previous studies have found that up to three-fourths of patients arrived after the time window for tPA had closed,” Madsen said in a news release. “Many patients across all groups do not arrive at the hospital in time, but this is particularly true for underrepresented minorities.”

The researchers mentioned a few limitations of the study, including that they could not determine why patients did not receive tPA. They also could not adjust for factors such as time to arrival, stroke severity, patient education and socioeconomic status.

“More research needs to be done to help figure out why many patients do not receive tPA,” Madsen said in a news release. “There is also a lot of work to do in the realm of stroke education so that patients recognize stroke symptoms and call EMS immediately.”