NEW YORK (Reuters Health) - In a year-long study conducted in Dallas County, Texas, women who called 911 for suspected heart-related symptoms had a 52 percent greater likelihood of experiencing delays in emergency medical services (EMS) compared with their male counterparts, even after adjusting for a number of factors.

Delays in EMS care "could lead to harm for a patient with serious heart disease," Dr. Thomas W. Concannon, who led the study, noted in a statement issued by the American Heart Association.

The data stem from an analysis of 5,887 calls made to 911 from January 1 to December 31, 2004, by people with suspected cardiac symptoms, half of whom were women. The area studied is covered by 98 EMS stations and 29 hospitals.

There were no serious delays in elapsed time from the 911 call to paramedics' arrival at the scene. Delays began after EMS crews arrived on scene and continued during transport to the hospital.

The average time that EMS spent at the scene was 19.9 minutes, and the average transport time from the scene to the hospital was 10.3 minutes. The median time in EMS care was 34 minutes. Delay in EMS care was defined as greater than 15 minutes beyond median elapsed time; thus, anyone in EMS care for 49 minutes or longer was considered to be delayed.

According to Concannon and colleagues, women arrived at the hospital on average just over 2.3 minutes later than men, "not long enough to be clinically meaningful."

However, approximately 11 percent of callers, or 647 patients, were delayed 15 minutes or more, which could cause harm, Concannon noted. And, compared with men, women were more than twice as likely to be in the delayed EMS care group.

"We looked at the influence of several patient- and neighborhood-level factors on delays in EMS and the patient's gender stood out," noted Concannon, who is assistant professor of medicine at the Institute for Clinical Research and Health Policy Studies at Tufts Medical Center in Boston. "We need to find out why women are delayed and reduce or eliminate the disparity," he added.

The study is published in the medical journal Circulation: Cardiovascular Quality and Outcomes. In an editorial published with the study, Dr. Joseph P. Ornato, chairman of the Department of Emergency Medicine at Virginia Commonwealth University in Richmond, say possible factors leading to the delay in EMS care for women include a longer time to perform an on-site electrocardiogram (EKG), and gender differences in accepting EMS care and transport or in choice of destination hospital.

The issue of possible existence of gender delay in EMS care is an important one that "deserves follow-up study for a definitive answer," Ornato wrote.

SOURCE: Circulation: Cardiovascular Quality and Outcomes, January 13, 2009.