Social Determinants of Type 2 Diabetes in Rural vs. Urban Communities

By Austin V. Joseph

Illustration by Junyue Ma

 

Introduction and Background

Type 2 diabetes is a chronic immunological disease resulting from the body’s inability to process insulin. It affects populations worldwide, with a global prevalence of  537 million adults (age 20-79), which is expected to rise to 783 million by 2045, making up over 10% of the world’s total population.^1,2 This condition is linked to comorbidities including hypertension, liver disease,  kidney disease, retinopathy, polycystic ovary syndrome, and obstructive sleep apnea. While the physical afflictions of type 2 diabetes are well documented, its economic implications are often neglected. People living with diabetes are put under an increased financial strain due to the costs of treatment, surgery, dialysis, etc. According to the CDC, people diagnosed with diabetes incur an average of $19,700 in annual medical expenses, which is over two times the medical expenses of a person without diabetes.³ Living with type 2 diabetes also creates occupational barriers due to disability, which can hamstring a person’s income. The effect of disabilities caused by diabetes often bleeds over to the patient’s family members who may have to assist them physically and financially. 

The most common physical risk factors associated with type 2 diabetes are poor diet, obesity, and family history. Sugar, refined carbohydrates, and processed foods are key dietary drivers of type 2 diabetes because they increase blood sugar levels at such a high rate that glucose cannot be sufficiently stored in the liver, which makes the job of insulin much more difficult.⁴ A poor diet, combined with a sedentary lifestyle will also increase the risk of obesity. Excess body weight causes increased insulin resistance in muscle and tissue cells.⁵ An individual with a family history of diabetes is more likely to develop the disease due to genetic predisposition, but more so due to the poor habits that may have been learned during the person’s formative years, such as an unhealthy diet and little to no exercise. While there is no cure for type 2 diabetes, individuals are usually placed on diet and exercise programs along with regular monitoring of body weight and hemoglobin A1C levels to prevent or treat the disease. 

The social determinants of health are the biggest drivers of health disparities globally, playing a massive role in influencing risk factors and the ability to use preventative measures for type 2 diabetes. These determinants are often connected to structural impediments, including delayed diagnosis, failure of therapies, and unaffordable treatment.⁶ Poor access to quality healthcare decreases the likelihood of receiving screening, checkups, or adequate treatment after the onset. In addition to the financial strain of utilizing care, individuals with low socioeconomic status are more likely to have limited healthy food options, which creates a compounding burden by subjecting them to an unhealthy diet. Individuals living in low-income communities often experience a hostile lived environment, increasing the levels of stress they endure, which is associated with a higher proclivity toward diabetes or risky behaviors that lead to diabetes. 

Despite its status as a rich nation, the United States has struggled to decrease the burden of diabetes, as morbidity and mortality rates have climbed over the decades. One of the pitfalls of large, diverse nations like the U.S. is that they are highly susceptible to health disparities among different demographics. Health disparities have been studied extensively with a focus on race, gender, sexual orientation, and income level. However, there may be a residential basis for disparate health outcomes in the U.S. This paper will critically examine peer-reviewed health literature that has determined significant differences in type 2 diabetes between rural and urban communities. This paper will then use this literature and other evidence to address the following question: What factors contribute to the disparities in type 2 diabetes prevalence in rural versus urban communities in the United States? 

 

Methodology

• Background Search → The purpose of this search was to retrieve reputable information on type 2 diabetes for the introduction. Google was used to get certain statistics such as global prevalence, mortality, future projections, and average expenditures of living with diabetes to contextualize the burden of this disease for the introduction. Information on the most current prevalence, mortality, and projection of type 2 diabetes was pulled from Diabetes Atlas. Information on healthcare expenditures and risk factors for diabetes was pulled from the CDC. Since poverty statistics are relevant in this literature, data derived from the USDA reported by the Rural Health Information Hub were referenced. All of these references are not produced from peer-reviewed literature but are from reputable databases, hence their inclusion in the citations. There are a total of seven references that were derived from this background search, one of them being a published review that yielded evidence-based information regarding the structural risk factors that may contribute to type 2 diabetes.
• Targeted Search → PubMed, Wiley Online Library, and Google Scholar were search engines used for my targeted search. Boolean operators were utilized to connect keywords such as “type 2 diabetes”, “rural”,  “urban”,  “United States,” “US,” or “America.”  In total this search yielded 45 results in PubMed, and over 100,000 results in the other two databases To explore literature on social determinants that may contribute to the burden of diabetes in rural communities, the terms “income”, “socioeconomic status” “education”, “physical activity” and “care” or “access to healthcare” were used, which yielded 23 results in total in Pubmed and over 100,000 in the other two databases. The cut down to 12 sources was determined by eligibility criteria and the elimination of studies that were conducted utilizing similar methods. References used in the results section are represented as AMA citations. 
• Inclusions and Exclusions → Literature that met the criteria for use as evidence needed to specifically research diabetes and/or determinants associated with diabetes, cover populations in rural and urban communities in the U.S., and be recent enough to be considered relevant in 2023. Included studies were based on rural and urban areas in the U.S. and covered type 2 diabetes diabetes, obesity, socioeconomic status or income, education, or quality of healthcare. If the study researched any of those topics without researching diabetes directly, it was still included because those are known determinants of diabetes. Eligible articles for review may include cross-sectional, randomized controlled trials, case-control studies, other systematic reviews, or published papers that reference public data. The type of article is not a concern for this evidence synthesis because both qualitative and quantitative data will be used to answer the research question. Due to the nature of the research question, it was anticipated that randomized controlled trials and case-control studies would not be found. Any literature that studies that conducted research outside of the United States was excluded, as the population of interest for this paper is rural and urban residents in the US. The age of what was considered a useful study was limited to three decades, so any research that was conducted before the 1990s was excluded in order to account for any changes to those findings due to interventions.

 

Results

Evidence indicates that there is a difference in diabetes outcomes between rural and urban communities in the United States and that rural communities are disproportionately affected, independent of predisposing characteristics (race, age, sex). In 2006, a cross-sectional analysis of data taken from a Behavioral Risk Factor Surveillance System (BRFSS) conducted on rural and urban residents from 47 states in the US showed that a higher proportion of rural residents reported diabetes than urban residents among all racial/ethnic classifications.⁷ According to the BRFSS, diabetes status was determined by responses to the question, “Have you ever been told by a doctor you have diabetes?” Those responding “Yes” were considered to be persons living with diabetes. This presents a limitation to the study, as accurate information can be barred by individuals who have not been diagnosed or have not seen a healthcare provider. Overall, this study suggests that there is merit in researching potential factors that may cause a higher burden of type 2 diabetes in rural communities. Further analysis of health literature denotes three possible risk factors of type 2 diabetes that disproportionately affect rural populations: socioeconomic status, lack of physical activity, and inadequate access to health services.

 

Socioeconomic Status

The evidence in this systematic review points to socioeconomics as the primary reason for a higher prevalence of type 2 diabetes in rural communities than in urban communities. As previously established, low-income communities create a compounding burden that subjects individuals to an unhealthy diet as well as the financial strains of utilizing care and missing work due to disability. Poverty has a direct impact on type 2 diabetes disparities and is more prevalent in rural residential areas. According to the United States Department of Agriculture (USDA) Economic Research Service, in 2019, 15.4% of people living in rural areas had an income below the federal poverty line, while those living in urban areas had a poverty rate of only 11.9%.⁸ As a result of a higher prevalence of poverty among rural communities, their residents are more likely to live in “food deserts”, or areas in which it is difficult to buy affordable or good-quality food. These environments are far more likely to contain fast food chains  and “convenience” stores that sell cheap processed foods as opposed to grocery stores and high-quality retail markets (i.e. Whole Foods) and fast-casual restaurants (i.e. Chipotle).¹⁹ The high saturation of fast foods combined with the shortage of fresh produce markets hinders the ability to consistently store adequate food in the household, causing uncertainty regarding the availability and quality of the family’s next meal. This phenomenon describes food insecurity. Sociologists Joy Rayanne Piontak and Michael D. Schulman explored spatial inequalities in food insecurity in the United States, specifically the problems of hunger and food access in non-metropolitan and rural localities. They found that households in the South, a heavily rural region, have the highest rates of food insecurity. A rather alarming finding from this study was that according to the USDA Food Environment Atlas, rural counties had an average 5.77% decrease in the number of grocery stores from 2007-2011.⁹

 In addition to the significant gap in poverty, rural communities have less socioeconomic mobility, further perpetuating their exposure to food insecurity and other type 2 diabetes risk factors. In 2018, Iryna Kyzyma, a researcher at the Luxembourg Institute of SocioEconomic Research and a Research Affiliate at the IZA Bonn, conducted a study to determine the comparative persistence of poverty in rural and urban areas. Results were derived from survey data from over five years (2008-2013) in which participants were asked about their socioeconomic situation every four months. The analysis concluded that rural residents experienced poverty at a higher rate than urban residents, and they also stayed in poverty for a longer time period. She also found that urban residents who rose out of poverty were less likely to fall back into poverty than rural residents who rose out of poverty.¹⁰ Given the nature of the U.S. economy along with the financial crisis of 2008, using survey data that expands beyond five years should make a stronger case. It should also be noted that the participants living in poverty could have experienced a certain level of discomfort in answering the survey questions truthfully. In summary, the eligible health literature covering the socioeconomic status of rural populations indicates that poverty is associated with food insecurity, poverty is more prevalent in rural communities than urban, and poverty persists for a longer duration in rural areas than urban areas. Given the connection between type 2 diabetes, food insecurity, and income, socioeconomic status can be a feasible determinant of residential disparities in type 2 diabetes.

Physical Activity

Low physical activity is a known indicator of obesity and type 2 diabetes. In this review, two articles conflicted on this topic. One study, published by Parks, et al in 2003, was a cross-sectional study that sampled adults of various socioeconomic backgrounds from urban and rural areas (n = 1818) to determine if there is a significant difference in physical activity based on the type of environment they live in. In this study, lower-income residents were less likely than higher-income residents to meet physical activity recommendations. Rural residents were least likely to meet recommendations; suburban residents were most likely to meet recommendations. Suburban, higher-income residents were more than twice as likely to meet recommendations than rural, lower-income residents.¹¹ The limitation of this study was that the population that was the least likely to meet recommendations was classified as rural and lower income, which could mean that low income is a confounder and that rural residence itself is not indicative of less physical activity. 

The other study, conducted by Liu, et al in 2008 was a cross-section of the National Survey of Children’s Health (NSCH), a module of the State and Local Area Integrated Telephone Survey, conducted by the National Center for Health Statistics of the US Centers for Disease Control and Prevention. The respondents of this survey were the child’s parent (95.7%) or guardian (4.3%) who knew the most about the child’s health and health care. The goal of this study was to use the Survey to get data on overweight status and levels of physical activity of children living in rural and urban areas to influence the design of policy interventions. According to the results, rural children (16.5%) were more likely to be overweight than urban children (14.3%). However, it was also found that urban children at 29.1% were more likely to be physically inactive than rural children at 25.2%.¹² These findings indicate that there are possible confounders within rural settings that contribute to being overweight. One can refer to the impact of socioeconomic status as well as access to healthy food options as a differentiator. A notable limitation of this study was its use of parentally reported data on height and weight, which may be inaccurate for children under ten years of age. In brief, physical activity may or may not be a driver of type 2 diabetes disparities in rural and urban areas but obesity may still be a concern. Further context on related factors affecting the populations in each area is necessary.

 

Access to Health Services and Information

Various health literature suggests that rural populations in America have less access to quality healthcare and health information compared to urban populations. Out of the eligible articles utilized for this paper, one systematic review and two surveys cover this topic. The systematic review, published in  2015,  reported significant differences in healthcare access between rural and urban areas. The studies in this review had findings of insufficient public transportation, staffing shortages, poor availability of broadband internet services, and patient reluctance to seek care based on cultural and financial constraints.¹³ One limitation when citing other systematic reviews is the reliance on watered-down information from the studies it references. There is always a possibility of biased selection with sources and the omittance of limitations of certain studies cited in the review.

A survey is a more effective measure to use when discussing access to health information and services because it allows individuals to self-report their experience with healthcare access and self-management. Since there is no cure for diabetes, health information and self-management are crucial components of prevention and treatment. Ultimately, practicing self-management and being well-informed of diabetes risk factors can lead to the lifestyle habits that are needed to prevent or reverse the disease. Two studies show evidence of inequitable access or use of health information and self-management among rural and urban populations in the United States. A survey-based study published in 2018 was conducted to determine who claims to have access to health information. Linear regression was utilized to show associations between rurality and health literacy. The findings were: compared to urban residents, rural residents had lower access to health information from sources including primary care providers, specialist doctors, blogs, and magazines, and less use of search engines. After accounting for socio-demographics, rural residents only had lower access to specialist doctors than urban residents.¹⁴ These findings may underscore a need for telehealth services focused on rural populations, including a database of relevant health information and available physicians. Lower employment of specialists in rural areas is a factor that should be considered as well. As for the limitations of this study, it was administered through an online survey that inquired about access to 25 health information sources. There may be a substantial population of urban residents without internet access who may also be lacking access to health information. Furthermore, the study was limited to 25 health information sources, which can exclude local, lesser-known sources. However, local sources may be considered most reliable in rural areas.

Another study analyzed surveys from the North Carolina Behavior Risk Factor Surveillance System (BRFSS) to determine differences in participation in diabetes self-management education (DSME) among urban and rural adults in North Carolina from 2012 to 2017. The results were self-reported by residents. According to the conclusion, there were persistent rural-urban disparities in DSME participation, with rural residents showing lower rates and the gaps widening. The exact rates between rural and urban communities were 52.3% versus 57.8% in 2012, 54.0% versus 56.5% in 2013, 48.8% versus 62.0% in 2015, and 46.7% versus 56.1% in 2017.¹⁵ While the restrictions of self-reported data from subjects must be considered, the results from this study suggest a significant difference between rural and urban participation in diabetes self-management programs within a single U.S. state. Regional/geographic confounders are not applicable in this study, which makes a powerful case for residential disparities on this issue. 

 

Discussion

Rural populations in the United States are more likely to develop type 2 diabetes than urban populations due to a combination of factors. An individual’s area of residence can be closely connected to their health outcomes due to the various elements that are experienced in their lived environment. There are connections to be made between the residential disparities in socioeconomic status and the residential disparities in the ability to utilize health information and services. The first connection deals with the geographic nature of rural settings. These communities are generally further away from the big metropolitans that are home to corporations, large health centers, and government buildings. Proximity (or lack thereof) to a revenue-generating city or district influences the “value” of the neighborhood as well as the level of federal investment in that area. Rural areas are also “out of the way” of public transit systems that allow all people in urban areas to travel to facilities without the use of a personal vehicle. That alone can influence someone’s willingness to seek care or healthier food options or available healthcare providers , whether they have the funds or not. The other connection between socioeconomic status and health utilization is rural education. While education is not a direct determinant of type 2 diabetes, it is heavily associated with income level, health literacy, and the availability of medical specialists in the area. The USDA reports that in 2017–21, the share of working-age adults (ages 25–64) with at least a bachelor’s degree was 37% in urban areas and 21% in rural areas, while the share of younger adults ages 25–44 with at least a bachelor’s degree was 40% in urban areas and 22%  in rural areas.¹⁶ These statistics represent a drastic disparity between rural and urban communities, which indicates that while low income is an established determinant of high type 2 diabetes, it is just the tip of the iceberg. There are fundamental issues with the rural education system that are possibly contributing to the persistence of poverty as well as the shortage of local medical specialists.  In a 2001 paper presented at the Appalachian Rural Systemic Initiative (ARSI) Conference on Understanding Achievement in Science and Mathematics in Rural School Settings, Hobart L. Harmon, a leading expert in public education in rural America outlined the inhibitors of educational advancement in rural areas. Harmon points to a cultural climate of modern education that is better suited for urban schooling. Modern America rewards personal ambition and self-determination¹⁷ and encourages young people to venture out of their parent’s homes and make their own societal contributions. Harmon suggests that this concept of individual mobility is less feasible in rural communities because rural school districts cannot generate sufficient local resources to adequately supplement the state school finance programs the way more affluent localities can.¹⁷ His paper further claims that rural schools experience inadequacy of facilities. According to data that was pulled from research done in 1996, 30% of rural and small-town schools have inadequate buildings and 50% of schools have at least one inadequate building feature.¹⁷ Harmon’s paper denotes inadequate investment in rural school systems to go along with an educational structure that does not align with rural community values. This suboptimal learning experience can not only lead to lower levels of educational achievement, but it can also cause poor teacher retention, which is supported by a recent article published by Dr. Richard M. Ingersoll in 2023. Using the Schools and Staffing Survey (SASS) and the National Teacher Principal Survey (NTPS) collected by the Census Bureau for the National Center for Education Statistics, nine cycles of data collection from 1987 to 2018 were recorded. Their results yielded that from two time periods: 1999-2004 and 2007-2018, the number of schools in urban areas increased by 26%, the number of students by 25%, and the number of teachers by almost a third. The number of schools in rural communities has decreased by over 28%, the number of students by 24% and the number of teachers by 19%. The study also found that rural schools have had more difficulties filling vacancies.¹⁸ Lack of teacher retention in these communities will only worsen the outcomes of educational attainment, income, health literacy, and professional development in healthcare, which will certainly worsen the outcomes of type 2 diabetes.

In the discussion of type 2 diabetes in rural populations, the impact of rural geography and the rural education system cannot be overlooked because they are so closely associated with socioeconomic status and the ability to utilize health resources. Residential disparities in type 2 diabetes may not have much to do with differences in physical activity. Poorer facilities in rural schools may have an impact on physical education courses for children, but that doesn’t indicate that they are inactive outside of school. Overall, the disparate burden of type 2 diabetes is driven by general differences in income, education, and spatial barriers.

 

Conclusion & Future Considerations

To conclude, the evidence presented in this systematic review not only indicated that there may be significant differences in the proportion of type 2 diabetes outcomes between rural and urban populations in the U.S., but it also referenced potential factors contributing to the disparity, including differences in socioeconomic status, physical activity, and access to health services and information. Of the 19 references utilized in this review, eight were cross-sectional studies, seven were findings derived from facts taken directly from a website or database, one was a paper presented at a conference, one was a mixed methods approach, and two were evidence-based systematic reviews. The limitations of each study were briefly explained throughout the results section. Randomized controlled trials and case-control studies were not found for this topic because this paper required studies in which urban and rural populations were surveyed and their area of permanent residence was an independent variable. No tests needed to be run and observational studies were more intuitive to answering my research question. 

A multilevel and tailored approach needs to be considered to address type 2 diabetes in rural areas. If transportation and telecommunication are immediate barriers to the reception of care or participation in diabetes self-management education, then it should be addressed at the local level. Complex transportation systems may be impractical in rural areas, but telehealth interventions should continue to be a priority within communities. Leveraging community values, such as faith can also be instrumental. Focus groups and DSME training can be held at local churches and schools to garner engagement. Fresh food initiatives such as Meals on Wheels should continue to expand in rural communities as well. Agricultural programs for residents should be encouraged wherever applicable, as there is evidence that they can be an effective alternative when grocery stores are not available or affordable.¹⁹ At the federal level, there needs to be dialogue regarding the inequitable funding of rural areas compared to urban areas, as well as the standardization of public schooling. Rural kids live almost entirely different lives than urban kids, and that needs to be reflected in the style of education they receive throughout their formative years. If the standard public education system is to be maintained, rural districts will require more subsidies to be better equipped to prepare their students. Efforts to improve diabetes care and staff retention in hospitals and schools should also be funded and supported politically.

 

References

1.  IDF Diabetes Atlas | Tenth Edition. https://diabetesatlas.org/.
2. Saeedi, Pouya, et al. “Mortality Attributable to Diabetes in 20–79 Years Old Adults, 2019 Estimates: Results from the International Diabetes Federation Diabetes Atlas, 9th Edition.”
3. How Type 2 Diabetes Affects Your Workforce | National Diabetes Prevention Program | Diabetes | CDC. 12 Nov. 2023
4. CDC. “The Insulin Resistance–Diabetes Connection.” Centers for Disease Control and Prevention, 20 June 2022
5. Excess weight and type 2 diabetes. https://www.honorhealth.com/medical-services/bariatric-weight-loss-surgery/patient-education-and-support/comorbidities-type-2-diabetes
6. Wu Y, Ding Y, Tanaka Y, Zhang W. Risk Factors Contributing to Type 2 Diabetes and Recent Advances in the Treatment and Prevention. Int J Med Sci 2014
7. Hale N, Bennett K, Probst J. Diabetes care and outcomes: disparities across rural america. Journal of Community Health.
8. Families with low incomes – rural services integration toolkit. https://www.ruralhealthinfo.org/toolkits/services-integration/1/high-needs-populations/families-with-low-incomes
9. Piontak, Joy Rayanne, and Michael D. Schulman. “Food Insecurity in Rural America.” Contexts
10. Kyzyma, Iryna “Rural-Urban Disparities in Poverty Persistence.” IRP Focus. 2018
11. Parks, S. E., et al. “Differential Correlates of Physical Activity in Urban and Rural Adults of Various Socioeconomic Backgrounds in the United States.” Journal of Epidemiology & Community Health
12. Liu, Jihong, et al. “Urban‐Rural Differences in Overweight Status and Physical Inactivity Among US Children Aged 10‐17 Years.” The Journal of Rural Health, vol. 24, no. 4, Sept. 2008
13. Douthit, N., et al. “Exposing Some Important Barriers to HealthCare Access in the Rural USA.”
14. Chen, Xuewei, et al. “Differences in Rural and Urban Health Information Access and Use.” The Journal of Rural Health
15. Luo, Huabin, et al. “Trends and Rural-Urban Differences in Participation in Diabetes Self-Management Education Among Adults in North Carolina: 2012-2017.” Journal of Public Health Management and Practice
16. Educational Attainment Improved in Rural America but Educational Gap with Urban Areas Grew for Bachelor’s Degrees and Higher.
17. Harmon, Hobart L. Education Issues in Rural Schools of America. May 2001
18. Ingersoll, Richard M., and Henry Tran. “Teacher Shortages and Turnover in Rural Schools in the US: An Organizational Analysis.” Educational Administration Quarterly
19. Valdez, Zulema. “Community Perspectives on Access to and Availability of Healthy Food in Rural, Low-Resource, Latino Communities.”