Spatial access to lung CTs in the US: 3 key takeaways
Most smokers in the United States live within 15 miles of a CT facility, according to research published this week in the Journal of the American College of Radiology, but the 20 percent who don’t could offer insight into boosting lung cancer screening rates and lowering death counts.
Tina D. Tailor, MD, of Duke University Medical Center’s radiology department in Durham, North Carolina, led the research, which explored geographic access to CTs for lung cancer screenings in a census tract-level population study. Tailor and her team geocoded 6,923 ACR-accredited CT facilities and calculated the driving distance to those facilities for 73,057 U.S. census tracts. After analysis, these were their biggest takeaways.
1. Adequate spatial access to CT services is key to a successful, nationwide lung cancer screening program.
Over the course of their research, Tailor and her colleagues found the average driving distance to a CT facility in census tracts with more than 500 smokers to be 4.3 miles, although the more rural the community, the farther the nearest CT facility tended to be.
The researchers said past work has proven that better spatial access to healthcare results in better outcomes. In communities with an in-county mammographic facility, for example, odds of advanced diagnoses declined while breast cancer screening rates skyrocketed.
“Extending such knowledge to lung cancer screening (LCS), it follows that CT facility access is a necessary component in assessing the capacity of imaging services to handle a population-wide LCS program, and further to identify at-need groups,” Tailor et al. wrote. “In this regard, small areas analysis, as performed here at a census tract level, permits examination of population variation that may be masked by conventional large-area analysis.”
2. Most American smokers live within 15 miles of a CT facility, though there’s considerable variation among states.
That more than 80 percent of smokers in the U.S. live within 15 miles of a CT service is promising, the authors wrote, but it also means more than nine million smokers live outside that range. Still, the data suggest barriers to implementing successful lung cancer screening programs aren’t limited to spatial considerations.
Tailor and her team said provider-level factors like awareness of screening guidelines and patient-level factors like insurance type, personal knowledge and financial abilities could also put strain on such initiatives.
“Although indirect costs, namely those not directly related to medical care, are challenging to quantify, they pose a burden because they are almost entirely (if not entirely) the patient’s responsibility,” they wrote.
3. Those living in densely populated areas are more likely to have greater spatial access to CTs.
Tailor et al. said this finding likely echoes other research, which has identified trends of resource disparities and poorer patient outcomes in rural communities. Urban areas are likely to have more hospitals, physicians and subspecialty services, because they’re designed to meet the needs of a wider clientele.
Lung cancer screening programs are thus more likely to be available and succeed in more densely populated areas, but the authors said that leaves some rural—though still screening-eligible—communities at a disadvantage. For instance, they wrote, some counties in Maine, Texas, Montana and Nevada see a high concentration of smokers, but the nearest CT facility is more than 100 miles away.
“Future work is needed to determine what proportion of cigarette smokers evaluated herein at LCS-eligible, and further to understand both spatial and nonspatial determinants of LCS access [and] how these factors affect LCS utilization,” Tailor and co-authors said. “Doing so is a fundamental step toward the necessity to match LCS resources to the at-need population.”
After graduating from Indiana University-Bloomington with a bachelor’s in journalism, Anicka joined TriMed’s Chicago team in 2017 covering cardiology. Close to her heart is long-form journalism, Pilot G-2 pens, dark chocolate and her dog Harper Lee.