Examining the Causal Effect of Social Exposures on Health: Challenges and Strategies for Causal Inference
by Nyjel Green
In order to reduce health disparities, public health treatments and policies must take into account the causal relationship between social exposures and health outcomes. It has been demonstrated that social determinants of health, including socioeconomic position, education, and access to healthcare, have a major influence on health outcomes. However, because of confounding variables and intricate causation pathways, assessing the causal influence of these social exposures is difficult. Healthcare access, as defined by the National Academies of Sciences, Engineering, and Medicine, is the timely use of personal health services to achieve the best possible health outcomes (Health Care Access and Quality - Healthy People 2030 | Health.Gov, n.d.). In the United States, about 1 in 10 people do not have health insurance, and according to Healthy People 2030, many individuals do not receive the health care services they need (Healthy People, 2030). Social exposures are often correlated with other factors that also influence health outcomes, making it difficult to isolate the true causal effect. For example, individuals with higher socioeconomic status may have better access to healthcare and healthier lifestyle behaviors, complicating efforts to attribute health improvements solely to social factors. A lack of access to health care can lead to negative results that impact individuals' health status who are at high rates of chronic conditions such as cardiovascular disease, cancer, and other significant health disparities. Healthy People 2030 health initiative focuses on improving timely, high-quality healthcare services access. However, interventions and strategies are needed to ensure that healthcare services and resources are being made readily available for all individuals regardless of insurance and healthcare coverage to promote the equal distribution of healthcare access and affordable, preventive care.
Healthcare access is not distributed equally or proportionally across our country. Many interrelated factors exacerbate these disparities. Health care disparities refer to a difference in a population's health insurance coverage access to and use of care. Rural areas in the United States often need more than adequate healthcare access (Healthcare Access in Rural Communities Overview - Rural Health Information Hub, n.d.). Obtaining healthcare in a timely manner is essential to access. Rural areas and populations often must travel long distances or make arduous journeys to obtain care. Lack of health insurance, institutional distrust, limited access to transportation, or lack of healthcare resources are all factors that contribute to these rural disparities (Rural et al.).
There lies a difference between urban and rural areas as it relates to the promotion and well being of health for its community members. In addition to transportation being an issue, the reliability of transportation also serves as an anchor. This, indeed, is a problem because the residents residing in rural areas who suffer from chronic disease require multiple visits to outpatient healthcare facilities. Without constant transportation, access to care is rendered. Often, African Americans rely on community health centers and emergency rooms as outpatient facilities due to a lack of primary care in their communities (Racism, Inequality, and Health Care for African Americans, 2019). Traveling outside one's community may be an option for most individuals; however, access to limited transportation and limited incomes for those living in rural areas does pose a problem. The number of primary care providers per capita is lower in rural communities than in urban areas. This becomes an issue at large because access to a health care provider is the first step in ensuring that one's health care needs are being met. Across America, 65% of rural counties are experiencing a whole or partial professional shortage (Rural et al.).
Although lack of insurance has been linked to adequate care, African Americans (one-third) and Hispanics (46%) are most likely to be uninsured compared to one-fifth of whites and Asian Americans (Minority Americans Lag Behind Whites On Nearly Every Measure Of Health Care Quality, 2002). A lack of access to health care can lead to negative results in individuals' health status who are at high rates of chronic conditions such as cardiovascular disease, cancer, and other significant health disparities. Compared to other ethnic groups, African Americans are 41% more prevalent for health disparities compared to other ethnic groups (Minority Americans Lag Behind Whites On Nearly Every Measure Of Health Care Quality, 2002). African Americans are 30% more likely to suffer from heart disease, cancer, diabetes, anxiety, or depression compared to their white counterparts. According to Healthy People 2030, African Americans' health status continues to deteriorate, which makes them more susceptible to Chronic conditions (National Academies of Sciences et al., 2017). Approximately 77% of African Americans aged 50 and older have been diagnosed with one of the following conditions mentioned previously in comparison to 68% of Hispanics, 64% of whites, and 42% of Asians. The social determinants of health contributing to the inequality of healthcare access and worsening of chronic conditioning experienced by African Americans are economic disadvantages, inequities in health education, and uneven access to healthcare resources (Social Determinants of Health - Healthy People 2030 | Health.Gov, n.d.). Taking these facts into account, the focus on how healthcare access to these targeted populations should be examined further, considering current interventions.
The strategies for addressing and attacking disparities in healthcare access and treatment are varied, broad, and often unsuccessful (Williams et al., 2008, p. 8). A coordinated effort to address medical and nonmedical determinants of health is needed as interventions move 'upstream,' the classic metaphor of solving public health problems. Williams and colleagues echo a broader call to focus more on the social determinants of health when thinking about healthcare interventions. Removing the focus from an individual behavioral problem allows for nuance in solutions and recognition of historical processes and structures. The need for broad, societal-level solutions which target social determinants of health (SDOH) is clear. The way our society functions on a day-to-day basis punishes those that are the most precarious. SDOH "are conditions in the environments where people are born, live, learn, work, play, worship, and age that affects a wide range of health, functioning, and quality-of-life outcomes and risks" (Social Determinants of Health - Healthy People 2030 | Health.Gov, n.d.). The Healthy People 2030 campaign aligns many of its goals within the realm of targeting the inequalities resulting from SDOH. "The prolonged negative impact of racism, discrimination, poverty, substandard housing and neighborhood conditions, insurance status, and
insufficient availability of and access to quality healthcare have all been linked to poor health outcomes among African Americans" (Copeland, 2005, p. 266). SDOHs are directly implicated within the inequalities surrounding healthcare access. Not being able to get to an appointment because the provider is too far away or without bus access impacts individual and community health. This example illuminates how the environment in which one lives impacts one's health care and health. Broadly, SDOHs are grouped into "economic stability, education access, and quality, health care access and quality, neighborhood, and built environment, and social and community context" (Social Determinants of Health - Healthy People 2030 | Health.Gov, n.d.; Williams et al., 2008). These are broad, societal-level problems, but programs that have targeted them have often successfully reduced health disparities. Within this context, acknowledging the success of specific medical interventions is essential in designing our programming and strategy.
To advance health and or social equity, interventions and programming should promote a "science of community and stakeholder engagement" (Brown et al., 2019, pp. 575-576). This is the structured and detailed process of enlisting the communities that bear the disproportionate brunt of inequities in healthcare access. With continuous processes of input and feedback, the programs and interventions can be most successfully tailored to make the most significant impact. One example of this, which Cooper and colleagues detail, is a partnership between an academic institution and a local church leadership collective. Focusing on a smoking intervention, "community members were integrally involved in every aspect of the study" (Cooper et al., 2002, p. 481). While this suggested intervention will include different components of an academic study, this type of community engagement is essential, especially when thinking about working for people who have historically marginalized communities.
In conclusion, while estimating the causal effect of social exposures on health presents significant challenges, leveraging innovative study designs and methodologies can enhance our ability to inform evidence-based interventions and policies aimed at promoting health equity.
References
Brown, A. F., Ma, G. X., Miranda, J., Eng, E., Castille, D., Brockie, T., Jones, P., Airhihenbuwa, C. O., Farhat, T., Zhu, L., & Trinh-Shevrin, C. (2019). Structural Interventions to Reduce and Eliminate Health Disparities. American Journal of Public Health, 109(S1), S72–S78. https://doi.org/10.2105/AJPH.2018.304844
Cooper, L. A., Hill, M. N., & Powe, N. R. (2002). Designing and evaluating interventions to eliminate racial and ethnic disparities in health care. Journal of General Internal Medicine, 17(6), 477–486. https://doi.org/10.1046/j.1525-1497.2002.10633.x
Health Care Access and Quality—Healthy People 2030 | health.gov. (n.d.). Retrieved December 1, 2022, from https://health.gov/healthypeople/objectives-and-data/browse objectives/health-care-access-and-quality
Healthcare Access in Rural Communities Overview—Rural Health Information Hub. (n.d.). Retrieved December 8, 2022, from https://www.ruralhealthinfo.org/topics/healthcare-access
Minority Americans Lag Behind Whites On Nearly Every Measure Of Health Care Quality. (2002, March 6). https://www.commonwealthfund.org/press-release/2002/minority americans-lag-behind-whites-nearly-every-measure-health-care-quality
Racism, Inequality, and Health Care for African Americans. (2019, December 19). The Century Foundation. https://tcf.org/content/report/racism-inequality-health-care-african americans/
Social Determinants of Health—Healthy People 2030 | health.gov. (n.d.). Retrieved September 15, 2022, from https://health.gov/healthypeople/priority-areas/social determinants-health