People treated for stroke at designated stroke centers appear to survive slightly longer than those treated at other hospitals, suggests a new study.

While the finding has important implications, it doesn’t change the most important message about stroke, which is to get help as soon as possible, said study author Dr. Ying Xian of the Duke Clinical Research Institute in Durham, North Carolina, and formerly of the University of Rochester Medical Center in New York, where he did the research.

“The most important thing for the patient is when you have a stroke attack, or you see people stroke attack, call 911 immediately,” he told Reuters Health. “Ideally, the EMS will transport people to the appropriate hospital.”

Most strokes occur when a blocked blood vessel causes some of the blood flow going to the brain to be cut off, damaging brain tissue that depends on that blood to survive.

Stroke is the third leading cause of death in the U.S., only topped by heart disease and cancer. Each year, nearly 800,000 people in the U.S. have a stroke and more than 130,000 people die as a result.

Within the last decade, both national and state programs have begun designating hospitals as official stroke centers when they demonstrate certain staff, facilities, and services believed to improve a patient’s outcome.

In addition, states such as New York require ambulances to take stroke patients straight to a designated center, as long as they can get care within two hours.

In the new study, published in the Journal of the American Medical Association, Xian and his colleagues tracked every adult admitted between 2005 and 2006 to a New York State hospital after an ischemic stroke, the most common type. About half of the nearly 31,000 patients ended up at stroke centers, while the rest were treated at hospitals without the designation.

One month after their treatment, 10.1 percent of the patients treated at stroke centers had died, compared to 12.5 percent of patients treated at other hospitals. A year later, those numbers were 22.3 percent and 26 percent, respectively.

The researchers also found that patients going to stroke centers were more likely to be treated with drugs that dissolve blood clots, but need to be given within a few hours of a stroke.

To make sure that the differences in these hospitals had to do specifically with stroke care and not overall quality, the authors compared the outcomes for patients treated for two other conditions, heart attacks and stomach bleeding, at both kinds of hospitals.

One month after being treated, those patients had died in equal numbers at the two types of hospitals, suggesting stroke centers were not just better all-around.

Although the differences in death rates may appear small, Dr. Mark Alberts, a neurologist at the Northwestern University School of Medicine who wrote an editorial accompanying the study, argued that such changes in percentages make a big difference when applied over the range of all the strokes that occur in a year.

While stroke centers may lead to better stroke outcomes on average, individual hospitals - stroke center or not - can still vary in the care they provide, and for many patients the best option may still be whatever hospital is closest, one expert stressed.

“Hopefully the take-home message is that it’s important for quality improvements to take place in hospitals,” Dr. Judith Lichtman, who studies stroke at the Yale University School of Public Health and wasn’t involved with the current study, told Reuters Health. “But I wouldn’t want someone to assume that they would not get excellent care at a non-certified hospital.”