A recent study under the direction of Huntsman Cancer Institute researcher Dr. Mia Hashibe has examined disparities in cancer survival and incidence between Utah's metropolitan and rural areas.
That's a mouthful. Here's what it means:
- The National Institutes of Health defines health status disparities as differences in rates of disease occurrence between population sub-groups like between difference races, the sexes, economic classes, and more.
- Incidence is just a way that researchers measure the number of diagnoses per year in a group of people, so any differences in incidence between Utahns who live in rural areas versus Utahns who live in metropolitan (city) areas would be considered health status disparities.
- Hashibe worked to understand whether such health status disparities exist between rural Utahns and Utahns living in metropolitan areas.
Other studies have looked at these health status disparities between rural and metro areas nation-wide, but Hashibe wanted to limit research to Utah because it has unique rates of tobacco and alcohol use, higher education than the national average, lower obesity rates, and a younger overall population. The low smoking rate in Utah was especially interesting to Hashibe. In the study, she suggests that Utah's rate of tobacco use is a good predictor of where the U.S. might be in 10 years.
Hashibe found that cancer patients in rural areas were more likely to be (among other things):
- diagnosed at a later stage
- not treated with radiation or surgery
- 75% of rural patients lived in counties with low pap smear rates, and 65% in counties with low mammography rates
The study says, "Rural residents were diagnosed with cancer at an older age and later stage, perhaps due to differences in access to care by distance to primary care, major cancer hospitals, as well as differences in insurance status."
The paper suggests that low rates of testing like pap smears and mammograms could lead to late diagnosis and ultimately lower survival.
Perhaps the most important findings were those she directly sought to study: survival and incidence. Do people living in rural areas have lower rates of cancer survival than in metro areas? Is cancer more frequently diagnosed in rural populations, than in city-living ones?
Rural Utahns had a 5.2% lower 5 year survival rate for cancer overall--with some kinds of cancer seeing lower survival rates in rural areas and some higher. You can see this in the difference between the heights of each pink bar and the purple one next to it. 5 year survival rate is a measure of how many cancer patients are still living 5 years after the day they're diagnosed with cancer.
Rural Utah cancer patients also had a 10% higher risk of death (at any time after diagnosis) overall than patients living in Utah's metropolitan areas.
Hashibe also found that overall cancer incidence--the rate of diagnoses of any type of cancer per year--to be slightly lower in rural areas than in cities. This also varies by kind of cancer, a which you can see in the height differences between each light blue bar with the darker one immediately beside it.
Now, on average, different kinds of people live in metropolitan areas and rural areas. In addition to the list above, Hashibe found that rural Utah residents were also:
- more likely to be American Indian or Alaska Native
- more likely to be non-Hispanic
- more likely to be male
- less likely to complete a college degree
- more likely to have a lower median income and more likely to live in poverty
So all the statistics Hashibe reported in her study were adjusted for age, sex, race, ethinicity, cancer stage at diagnosis, education, income, obesity, and smoking.
What does all this mean? Rural Utahns are slightly less likely to be diagnosed with cancer than Utahns living in cities. This could be explained by two things: a) people living in rural areas could be less likely to get cancer, or b) people living in rural areas could be more likely to have cancer which is never diagnosed. On top of this difference in diagnosis, cancer patients living in rural Utah are 5.2% less likely to survive to a point 5 years after their diagnosis with cancer, and 10% higher risk of death at any point in time.
Further research will have to test the 'whys' behind these findings, so that cancer care can be improved for Utahns living in rural areas. Hashibe is not the only researcher at HCI working on this. There is an entire group of researchers trying to find ways to better prevent and treat cancer for rural residents. Their name: HOPE.
HCI is the closest cancer center to 17% of the continental U.S., and a significant proportion of this land is either rural (land on which between 6.1 and 99.9 people live per square mile) or frontier (fewer than 6 people per square mile). HOPE researchers aim to narrow these gaps in diagnosis and treatment for those people. But first, researchers like Hashibe have to find them.
HSRIC: Health Disparities. (2018, April 10). Retrieved April 13, 2018, from https://www.nlm.nih.gov/hsrinfo/disparities.html
Hashibe, M., Kirchhoff, A. C., Kepka, D., Kim, J., Millar, M., Sweeney, C., . . . Mooney, K. (2018). Disparities in cancer survival and incidence by metropolitan versus rural residence in Utah. Cancer Medicine. doi:10.1002/cam4.1382