Disparities in breast cancer subtype, staging, and access to mammography services in the Lower Mississippi Delta Region

The Delta Regional Authority (Delta Region) is a federal-state partnership aiming to improve socioeconomic conditions in 252 counties and parishes in the eight state Lower Mississippi Delta Region (LMDR). The Delta Region has a higher proportion of black residents, is poorer, and is more rural than the country as a whole. It also has far higher breast cancer mortality rates than the nation. Black women in the Region have higher breast cancer mortality rates than white women in the Delta Region and have higher breast cancer mortality rates than black women in other parts of the country. More aggressive breast cancer subtypes, more advanced stage at diagnosis, and less access to screening mammography may play a role in these high mortality rates. Studies have shown that black women have higher rates of the most aggressive breast cancer subtype-- triple-negative--than white women and are often diagnosed at a more advanced stage. Additionally, while poor and rural women tend to have lower incidence rates of breast cancer, they often have a higher odds of late-stage cancer and less access to screening services. This dissertation sought to elucidate the Delta Region’s breast cancer mortality disparity by determining differences between the Delta and non-Delta Regions of the LMDR and by exploring racial differences within the Delta Region among the following areas: breast cancer subtype, breast cancer staging, and spatial access to mammography services. Population-based cancer surveillance data from the North American Association of Central Cancer Registries were analyzed to determine age-adjusted, subtype-specific incidence rates and rate ratios in the Delta and non-Delta Regions of the LMDR. Multilevel negative binomial regression models were constructed to evaluate if identified disparities were attenuated after accounting for race/ethnicity, age, and contextual factors. These analyses were performed for all cases by subtype and separately for early stage and late stage cancers by subtype. Higher rates of triple-negative breast cancer were identified in the Delta Region compared to the non-Delta Region, but this was attenuated in multivariable models. However, triple-negative breast cancer rates were higher in the urban Delta compared to the urban non-Delta, even after accounting for race/ethnicity, age, and contextual factors. Black residents in the Delta Region had higher rates of hormone receptor-negative breast cancers and higher rates of breast cancer overall compared to white women in the Region. Further, there were no particularly notable differences in late-stage breast cancers between the Delta and non-Delta Regions. However, black women in the Delta Region had lower rates of early-stage breast cancer, but higher rates of late-stage breast cancers compared to white, Delta Region women, even after accounting for age and contextual factors. To evaluate spatial access to mammography services, this study applied the enhanced two-step floating catchment area method to Food and Drug Administration data and census tract level American Community Survey data. The Food and Drug Administration data provided addresses of all approved mammography facilities in the LMDR and adjacent states while American Community Survey data were used to estimate populations of women of recommended screening age at the census tract level. For the most part, women in the Delta Region had similar spatial access to mammography services as non-Delta Region women. However, clusters of low spatial access within the Delta Region were identified in parts of Arkansas, Tennessee, and Mississippi. The identified higher incidence of breast cancer in black women in the Delta compared to white women was driven by higher rates of hormone receptor-positive cancers, but further research is needed to determine what individual or contextual factors may be driving the higher incidence rates. Additionally, this dissertation underscores the importance of community-based, culturally tailored interventions to improve mammography utilization rates and subsequently improve early detection of hormone receptor-positive breast cancers. Furthermore, this dissertation signaled a need for improved state-level policy and geographically targeted regional resource allocation to improve screening access and utilization. Additionally, these findings provide the foundation for further research to explore regional breast cancer disparities at other points along the cancer control continuum (e.g. treatment), to examine regional disparities for other cancers, and to promote collaborative academic partnerships across the Delta Region

Multilevel Analysis in Rural Cancer Control: A Conceptual Framework and Methodological Implications

Rural populations experience a myriad of cancer disparities ranging from lower screening rates to higher cancer mortality rates. These disparities are due in part to individual-level characteristics like age and insurance status, but the physical and social context of rural residence also plays a role. Our objective was two-fold: 1) to develop a multilevel conceptual framework describing how rural residence and relevant micro, macro, and supra-macro factors can be considered in evaluating disparities across the cancer control continuum and 2) to outline the unique considerations of multilevel statistical modeling in rural cancer research. We drew upon several formative frameworks that address the cancer control continuum, population-level disparities, access to health care services, and social inequities. Micro-level factors comprised individual-level characteristics that either predispose or enable individuals to utilize health care services or that may affect their cancer risk. Macro-level factors included social context (e.g. domains of social inequity) and physical context (e.g. access to care). Rural-urban status was considered a macro-level construct spanning both social and physical context, as “rural” is often characterized by sociodemographic characteristics and distance to health care services. Supra-macro-level factors included policies and systems (e.g. public health policies) that may affect cancer disparities. Our conceptual framework can guide researchers in conceptualizing multilevel statistical models to evaluate the independent contributions of rural-urban status on cancer while accounting for important micro, macro, and supra-macro factors. Statistically, potential collinearity of multilevel model predictive variables, model structure, and spatial dependence should also be considered

Population Structure Analyses Provide Insight into the Source Populations Underlying Rural Isolated Communities in Illinois

We have previously hypothesized that relatively small and isolated rural communities may experience founder effects, defined as the genetic ramifications of small population sizes at the time of a community’s establishment. To explore this, we used an Illumina Infinium Omni2.5Exome-8 chip to collect data from 157 individuals from four Illinois communities, three rural and one urban. Genetic diversity estimates of 999,259 autosomal markers suggested that the reduction in heterozygosity due to shared ancestry was approximately 0, indicating a randomly mating population. An eigenanalysis, which is similar to a principal component analysis but ran on a genetic coancestry matrix, conducted in the SNPRelate R package revealed that the majority of these individuals formed one cluster with a few putative outliers obscuring population variation. An additional eigenanalysis on the same markers in a combined data set including the 2,504 individuals in the 1000 Genomes database found that most of the 157 Illinois individuals clustered into one group in close proximity to individuals of European descent. A final eigenanalysis of the Illinois individuals with the 503 individuals of European descent (within the 1000 Genomes Project) revealed two clusters of individuals and likely two source populations; one British and one consisting of multiple European subpopulations. We therefore demonstrate the feasibility of examining genetic relatedness across Illinois populations and assessing the number of source populations using publicly available databases. When assessed, it becomes possible for population structure information to contribute to the understanding of genetic history in rural populations

Identifying Areas with Disproportionate Local Health Department Services Relative to Opioid Overdose, HIV and Hepatitis C Diagnosis Rates: A Study of Rural Illinois

Background: U.S. rural populations have been disproportionately affected by the syndemic of opioid-use disorder (OUD) and the associated increase in overdoses and risk of hepatitis C virus (HCV) and human immunodeficiency virus (HIV) transmission. Local health departments (LHDs) can play a critical role in the response to this syndemic. We utilized two geospatial approaches to identify areas of discordance between LHD service availability and disease burden to inform service prioritization in rural settings.Methods: We surveyed rural Illinois LHDs to assess their OUD-related services, and calculated county-level opioid overdose, HIV, and hepatitis C diagnosis rates. Bivariate choropleth maps were created to display LHD service provision relative to disease burden in rural Illinois counties. Results: Most rural LHDs provided limited OUD-related services, although many LHDs provided HIV and HCV testing. Bivariate mapping showed rural counties with limited OUD treatment and HIV services and with corresponding higher outcome/disease rates to be dispersed throughout Illinois. Additionally, rural counties with limited LHD-offered hepatitis C services and high hepatitis C diagnosis rates were geographically concentrated in southern Illinois. Conclusions: Bivariate mapping can enable geographic targeting of resources to address the opioid crisis and related infectious disease by identifying areas with low LHD services relative to high disease burden

Guidelines for reporting of statistics for clinical research in urology

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/148242/1/bju14640.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148242/2/bju14640_am.pd

The Problem of the Color Line: Spatial Access to Hospital Services for Minoritized Racial and Ethnic Groups

Examining how spatial access to health care varies across geography is key to documenting structural inequalities in the United States. In this article and the accompanying StoryMap, our team identified ZIP Code Tabulation Areas (ZCTAs) with the largest share of minoritized racial and ethnic populations and measured distances to the nearest hospital offering emergency services, trauma care, obstetrics, outpatient surgery, intensive care, and cardiac care. In rural areas, ZCTAs with high Black or American Indian/Alaska Native representation were significantly farther from services than ZCTAs with high White representation. The opposite was true for urban ZCTAs, with high White ZCTAs being farther from most services. These patterns likely result from a combination of housing policies that restrict housing opportunities and federal health policies that are based on service provision rather than community need. The findings also illustrate the difficulty of using a single metric—distance—to investigate access to care on a national scale

The Intersection of Rural Residence and Minority Race/Ethnicity in Cancer Disparities in the United States

One in every twenty-five persons in America is a racial/ethnic minority who lives in a rural area. Our objective was to summarize how racism and, subsequently, the social determinants of health disproportionately affect rural racial/ethnic minority populations, provide a review of the cancer disparities experienced by rural racial/ethnic minority groups, and recommend policy, research, and intervention approaches to reduce these disparities. We found that rural Black and American Indian/Alaska Native populations experience greater poverty and lack of access to care, which expose them to greater risk of developing cancer and experiencing poorer cancer outcomes in treatment and ultimately survival. There is a critical need for additional research to understand the disparities experienced by all rural racial/ethnic minority populations. We propose that policies aim to increase access to care and healthcare resources for these communities. Further, that observational and interventional research should more effectively address the intersections of rurality and race/ethnicity through reduced structural and interpersonal biases in cancer care, increased data access, more research on newer cancer screening and treatment modalities, and continued intervention and implementation research to understand how evidence-based practices can most effectively reduce disparities among these populations

Radon 101

Radon 101 Brown Bag Session held on January 27, 2017 in the Medical Library at SIU School of Medicine. Two speakers presented on the following topics: Radon for Homeowners - Patrick Daniels, Bureau of Radiation Safety, IEMA Radon Testing Patterns in Illinois and Implications for Public Health and Medical Practice - Whitney Zahnd, Office of Population Science and Policy, SIU Medicin