People living in low-income communities wait about four minutes longer for ambulances to respond to their call for help when they are having a heart attack, a new study has found.

In communities with annual median incomes between $57,000 and $113,000, the study found that ambulances arrive in an average of 37.5 minutes – faster than in communities where the annual median income is between $20,250 and $42,642, where the typical wait time is 43 minutes.

Neither result is anywhere near industry benchmarks of 4, 8, and 15 minutes for delivering specific services in response to heart attack symptoms.

Among the possible reasons for the difference in response times, the study’s authors suggest, are hospital closures in and around low-income areas, EMS protocols that call for emergency response from facilities that specialize in cardiac care that may be farther from low-income communities, and a reduced number of private ambulance services serving lower-income areas.

Such findings have important implications for the communities served by private safety-net hospitals.

Learn more about the study, its methodology, and its findings in the report “A US National Study of the Association Between Income and Ambulance Response Time in Cardiac Arrest,” which can be found here, on the JAMA Open Network web site.