Demographic Disparities in Distance to Stroke Care Greater in Rural US

People living in rural areas of the United States not only have to travel farther for certified stroke care than their urban counterparts, but also feel a greater impact from demographic disparities, both of which might have a detrimental impact on patient outcomes, researchers have found.

Parts of the country with greater proportions of individuals who were 65 and older, uninsured, or of American Indian ancestry had, on average, greater distances to the nearest stroke center capable of administering IV thrombolysis, and these differences were exacerbated in nonurban areas. Moreover, lower median income was tied to longer trips for stroke care in nonurban—but not urban—areas, report Cathy Yu, BS (Washington University School of Medicine, St. Louis, MO), and colleagues in a study published online June 10, 2021, ahead of print in Stroke.

“Rigorously quantifying disparities in proximity to timely and life-saving stroke care can bolster efforts to implement infrastructure improvements,” Yu et al write. “Future research is needed to correlate disparities in proximity to stroke care with clinical outcomes.”

Senior author Akash Kansagra, MD (Washington University School of Medicine), told TCTMD it is known that stroke outcomes worsen as treatment times increase. “In a sense we can translate these numbers using that data, that if a patient has to travel an additional mile that might mean an additional minute or two in which that patient is not having their stroke treated,” he said. “And what’s really alarming is that you actually have to scale this up by the size of the population, that these disparities exist for millions of patients at a time, and so the potential harm from even a mile or two of added distance can be quite significant.”

That residents of rural America have to travel farther for stroke care is not surprising, Kansagra said, because it “fits with one of the challenges we’ve identified over many years: that patients in sparsely populated areas just don’t have access to large hospitals of the type that exist in urban areas.”

On the other hand, the finding that uninsured individuals were more distant from care was “surprising and unfortunate,” he said, and “that tells me that there’s a role for planning of hospital placement that goes beyond just hospital-initiated efforts, that there’s a role for a national thought process on how care should be distributed.”

A National Look

Over the past decade, there have been concerted efforts put toward improving the speed at which patients access stroke care based on the understanding that delays to treatment can worsen patients’ outcomes, and treatment times have come down, Kansagra said. There remains a lot of work to be done in the prehospital setting, however. “Events over the last few years have really opened our eyes to additional sources of disparity that occur even before the ambulance phase of care,” he said. “So that’s really what this study is intended to address.”

For the study, which builds on smaller-scale research efforts, the investigators used multiple data sources: the US Census Bureau’s 2014-2018 American Community Survey; a list of hospitals certified by state or national bodies to provide IV thrombolysis; and geographic information from a public mapping service. They calculated road distances to the nearest stroke center for each census tract, and examined the impact of various demographic factors.

The analysis included 2,388 stroke centers and 71,929 census tracts home to roughly 317 million Americans. More than two-thirds of the tracts (69%) were considered urban. Population density was 1,481 people per square kilometer in urban areas and 52 per square kilometer in nonurban areas.

Overall, the average distance from the nearest stroke center was 6.2 km for a typical urban census tract and 30.2 km for a typical rural census tract.

Several demographic factors were linked to travel distance. A 1% increase in the proportion of uninsured individuals was associated with a greater distance of 0.2 km in urban areas and 0.27 km in nonurban areas. Similarly longer distances were seen in tracts with greater percentages of American Indian residents (0.10 and 1.06 for urban and nonurban areas, respectively).

Having more residents age 65 or older was associated with longer trips to stroke centers only in nonurban areas (0.51 km per 1% increase). The impact of median income differed based on the type of census tract—each $10,000 increase in income was tied to a 5.04-km shorter distance to the nearest stroke center in rural areas, but a 0.17-km greater distance in urban areas.

“These results are clinically important not only just for the sheer magnitude of demographic disparity in nonurban tracts but also because many demographic groups with reduced proximity to certified stroke care, such as the elderly, uninsured, and American Indian populations, also have generally higher stroke incidence or face additional barriers to care besides distance,” Yu et al write. “Efforts to address disparities in these at-risk populations may thus be particularly effective in elevating access to stroke care nationwide.”

Working to Solve the Problem

The investigators note, however, that “urbanicity itself is perhaps the largest source of disparity in proximity to stroke care,” which “may reflect the historical preference for urban and more-profitable hospitals in the stroke certification process.”

To address this issue, they say, “certifying bodies must continue to encourage development and certification of stroke centers in nonurban areas and emphasize return on investment in terms of health benefits to citizens rather than financial benefits to hospitals.

“Simultaneously,” they continue, “state legislatures can work to develop more integrated and coordinated systems of care that can more rapidly triage and transfer nonurban patients with stroke to the most appropriate stroke center. State-level stroke legislation of this form has been shown to improve access to stroke care.”

In addition, Kansagra said, there’s a need to continue working with emergency medical services (EMS) systems while waiting for more hospitals to be built in areas that need them. “In the interim, it’s really important to ensure that we make very robust the EMS infrastructure that exists in rural America, so that at a minimum these patients can have the option to get to emergency stroke care even if that care is not as quick as we would like,” he stressed.

And finally, it has to be acknowledged that there are a multitude of barriers—economic, social, and cultural—beyond just proximity to stroke centers that impact access to care, Kansagra said, noting that patient education about the importance of seeking treatment for stroke symptoms continues to be important, particularly in rural areas.

This study “is by no means the final word in how to develop a more equitable health system,” he said, “but this is a part of that understanding and we hope that this will be the first of many studies by many groups that are really interested in building a better system for all.”

Indeed, Michael Mullen, MD (University of Pennsylvania, Philadelphia), and Olajide Williams, MD (NewYork-Presbyterian/Columbia University Irving Medical Center, New York, NY), write in an accompanying editorial: “These study findings challenge the current self-initiated approach to stroke center designation as a viable path to addressing geographic inequities and raise the need to consider alternative and more innovative approaches that optimize population coverage.”

Despite some limitations, they write, “we believe that this work is important and highlights an ongoing need to evaluate developing systems of stroke care through an equity lens.”