Mapping a new future for GIS

What can geographic information systems do for healthcare?
By Mike Miliard
04:03 PM

Electronic health records are obviously critical tools for healthcare improvement, but they alone aren't enough to truly transform patient and population health. As more and more IT investments go towards analytics tools to uncover trends and patterns in care delivery and wellness, one type of technology is starting to make inroads: geographic information systems.

GIS – it can stand for geographic information systems, as well as geographic information science – refers to the ability of computers to capture, store and present varieties of geographic data. According to Esri, a Redlands, Calif.-base GIS software developer, GIS technology "lets us visualize, question, analyze, interpret, and understand data to reveal relationships, patterns and trends."

Clearly, few industries are better served by those capabilities than healthcare. Slowly, providers are realizing that GIS can help clinicians arrive at insights that wouldn't necessarily come with just EHRs alone.

For instance, Brian Jacobs, MD, chief medical information officer at Children's National Medical Center in Washington, authored a 2012 report that applied GIS technology to EHR data to examine the prevalence of childhood obesity in three distinct populations in and around D.C.

"EHR provides a rich source of electronically accessible discrete patient data around demographics, race, age, patient address, vital signs, laboratory results, radiology results and healthcare provider clinical documentation," Jacobs wrote. "As this detailed data are electronically available, there is an opportunity to aggregate, analyze and compare their geographic characteristics to related regional co-variables utilizing geospatial information systems technology.

"The use of GIS in the evaluation of EHR-derived data is of major significance to investigators as it permits geographic and co-factor specific targeting of epidemiologic methods, and, preventive and therapeutic treatment trials for patients with various conditions," he added.

Another recent whitepaper spotlighted the benefits that can be achieved by integrating GIS into primary care practice. Ethan M. Berke, MD, associate professor of community and family medicine at the Dartmouth Institute for Health Policy and Clinical Practice, wrote in the Journal of the American Board of Family Medicine how "more advanced spatial analytic techniques allow for explorations of 'hot spots' or clusters of infectious diseases and malignancies."

Beyond the obvious pop health applications, however, "we can go further," he wrote. 

"Every individual lives somewhere and interacts with their built and natural environment," according to Berke. "These responses to habitat, be they physical or emotional, define who we are and, importantly, impact our physical and mental health." 

From the "protective association between walkable neighborhoods and depression in older adults" to "associations between the built environment and levels of obesity," studies have shown the importance of patients' locations. "Because we spend 100 percent of our time somewhere, it is reasonable to expect that place matters when it comes to our health," he wrote.

Whether it's climate or crime, outside influences on a person's environment can affect his actual wellness – but smart use of GIS and EHRs in tandem can help target care interventions to those who need it most.

"Neighborhood characteristics such as safety, pollution, and availability of fresh foods can have substantial impacts on the health of individuals," write Christopher L. Simpson and Laurie L. Novak in a 2013 AMIA study titled, "Place Matters: The problems and possibilities of spatial data in electronic health records."

Since EHRs have patients' addresses, those "can be rapidly geocoded to produce computational data elements that, when linked to referential data such as crime rates, climate information, pollution/air quality and neighborhood walkability scores, can produce actionable alerts, reminders and other events for clinical decision support, care coordination and outreach," write Simpson and Novak.

For example, they write, integration of GIS with the EHR would give clinicians data about chronic disease patients who "may have experienced disruption from a natural disaster, and provide a basis for outreach and support for affected individuals."

Sara L. McLafferty is the department head and a professor of geography and geographic information science at the University of Illinois at Urbana-Champaign. She's been at the forefront of GIS and geospatial analysis for years, keenly interested in how the places where we live, work and interact affect our well-being."

For instance one of her studies on the geography of health, funded by the American Cancer Society, looks at how placed-based inequalities, with regard to things such as access to health services, impact prostate and colorectal cancer outcomes in Chicago.

"I'm interested in health disparities and how those are related to the kinds of neighborhoods and environments that people live in," says McLafferty. "If you live in an area that has a lot of hazardous waste sites, high crime rates and few physicians nearby, your health outcomes might be much worse than somebody who lives in a more advantaged neighborhood." GIS first made an impact on healthcare back in the late '80s, she says, when the systems became more accessible to people. "Desktop systems for GIS were first developed, and the data we need to go into GIS became more readily available," she says. 

In the decades since, GIS has "definitely changed a lot," says McLafferty. "For one, we can handle much larger data sets. Also, you have data sets that are, in some cases, real-time data: tweets about flu, or things like that, that are coming in real-time – we can analyze them on the fly as they happen."

The other big change is that "a lot of healthcare organizations now keep geospatial data  – patient records, hospital admissions, things like that, that have a geographic identifier," she says. "We can then analyze those in GIS to understand where patients are coming from, what types of patients have what types of health problems."

Beyond patient-focused care, that insight can help with organizational advancements, such as informing plans for locations of new clinics, for instance.

Still, says McLafferty, "I think (GIS) is not used to its full potential. There are some healthcare organizations that are doing this. Some of the larger groups like, say, Blue Cross Blue Shield or the hospital chains. But a lot of healthcare providers have not made the leap into GIS."

That said, "I think we're going to see that in the next several years," she says, "especially with electronic medical records. Those are going to be geocoded and then used to their potential."

A big driver, of course, is the fact that accountable care means hospitals will be incentivized – beyond the obvious goal of improving the health of their community – to better target their care interventions and reduce readmissions.

"One of the basic strengths of GIS is the ability to map and visualize things – you can actually see where your patients are coming from if you're a hospital: what neighborhoods, where do they come from in relation to other hospitals and clinics, and so-on," says McLafferty.

"Beyond that, we can look at proximity – where, for a particular population, how many highways might be generating pollution. Where are the bus depots? How far away? We can even do things like model the flow of air pollution from highways over to neighborhoods. In my current work, we're creating maps that show where people have very little access to primary healthcare. You've heard of food deserts, these are more like doctor deserts."

McLafferty says she "definitely expects to see more use of these systems in the future – I think we're already starting to see that. If you look back to the 1990s, when this technology was just becoming available, there were very few healthcare organizations that were using these methods. Most of the use was in federal government agencies or some very large health departments. Nowadays, we're starting to see technologies trickle down to smaller public health departments and larger health organizations."

Some of the impetus stems simply from ease of use, she says: "We have things like Google Maps – people are able to do mapping on their own fairly easily, and people's general awareness of mapping is increasing."

The other big pivot toward the future has come in just the past five years or so: widespread adoption of EHRs themselves.

"A lot of the data is now in computerized form rather than being in those old paper files that sat in doctors' offices and could not be used," says McLafferty. "The EHR revolution is also creating a revolution in GIS applications."