ASPO Abstracts
Urban and rural cancer mortality disparities in Ohio
Category: Cancer Health Disparities
Conference Year: 2020
Abstract Body:
Purpose: Overall (OS) and breast cancer (BrCa) specific survival has been improving as a whole;
however, these gains are disproportionate across population groups. Therefore, our aim was to evaluate
OS and BrCa specific survival (CSS) rates, comparing rural and urban regions.
Methods: We analyzed data from the Ohio state cancer registry, the Ohio Cancer Incidence Surveillance
System (OCISS), which includes population-based cancer incidence and mortality data among Ohio
residents from 1996-2016. Rural and urban county designations were based on the rural-urban continuum
codes (RUCC), a variable that classifies metropolitan counties by the population size of their metro area,
and nonmetropolitan counties by degree of urbanization and adjacency to a metro area. Results from a
Cox proportional hazards regression model adjusted for age, race and stage at diagnosis are presented
comparing OS and BrCa CSS between urban and rural settings.
Results: We found that among the 151,212 women diagnosed with BrCa, there were 54,177 (36%) total
deaths and 20,309 (13%) BrCa specific deaths. Residents of rural counties diagnosed with BrCa have a
decreased OS compared to urban residents (HR = 1.02, 95%CI = 1.00, 1.04, p=0.03). Although this result
was primarily driven by the association observed in white women (HR=1.03, 95%CI = 1.00, 1.05, p=0.02),
a similar directional and strength of effect was observed in African American (AA) women (HR=1.02,
95%CI = 0.87, 1.18, p=0.78). The lack of statistical significance among AA women is likely due to
statistical power. Subsequent studies will assess RUCC and agriculture exposures for the ten most
common cancers in Ohio.
Conclusions: In Ohio, women diagnosed with BrCa residing in rural counties have a higher risk of mortality
and experience less survival gains compared to women in urban counties. Poverty, unhealthy lifestyle
choices, access to healthcare, and exposure to certain environmental risk factors, particularly agriculture
related factors such as fertilizer and pesticides may be impacting this disparity. By identifying ecological
associations in Ohio rural and agricultural regions with higher mortality rates of BrCa, we can better
implement safety standards and awareness of these risks to decrease cancer mortality.
Keywords: cancer disparities, rural, urban