With contributions from Rujuta Takalkar and Natalia Wilson, MD, MPH
We concluded the first blog in this series with the observation that health status appears to be a major modulator of disease severity. While the majority of covid19 cases appear to be mild, older adults and people with pre-existing conditions are at greater risk of hospitalization and death from COVID, with conditions like hypertension, obesity, and diabetes topping the list of key culprits.
Although nearly two thirds of the US population has at least one chronic condition, some demographic groups suffer from chronic disease at a higher rate than the general population. They are also more vulnerable to additional medical conditions, including communicable diseases (e.g., the flu). In the case of covid, there are subgroups of most vulnerable people. One group are older adults, with 80% of those aged 65+ having at least one chronic condition and 68% having two or more. Racial and ethnic minorities, especially African Americans, Latinos, and Native Americans, comprise another vulnerable subgroup. These populations are more likely to have underlying chronic conditions such as diabetes, heart disease, and obesity. Sadly, but perhaps not surprisingly, these vulnerable populations are bearing a disproportionate burden of covid morbidity and mortality.
Americans aged 65+ account for ~80% of all covid deaths in the US, with nursing homes residents accounting for over 40% of all covid deaths in the US. Even with the recent trends, that show the disease skewing toward a younger demographic, the 65+ population still accounts for the highest share of covid hospitalizations. Minorities are also over-represented in national covid statistics. According to the CDC data, African Americans account for 23% of all covid deaths and 33% of all covid hospitalizations, while making up only 13% of the total US population. These trends are even more pronounced at the local level. For example, an analysis of hospitalizations in the Oschner Health System in Louisiana showed that Blacks account for ~77% of hospitalized covid cases and ~71% of covid deaths, while making up 31% of the overall patient population. Native Americans are another minority group that has been heavily impacted by the virus. In Arizona, the mortality rate for Native Americans is five times higher than other racial and ethnic groups, while The Navajo Nation, which spans the states of Arizona, Utah, and New Mexico, experienced the highest per-capita infection rate, surpassing that of New York. It should be noted, that the above Oschner study also highlighted that once health status is accounted for, the impact of race/ethnicity disappears.
Why is this happening? Health status is a complex interplay between the determinants of health – one’s behavior, genetics, social circumstances, healthcare, and environmental exposures. The social determinants of health (SDOH) broadly encompass these last three areas and are very influential on behavior and health outcomes. Key areas of consideration are economic stability, education, neighborhood and built environment, health and health care, and social and community context. Even a cursory review of these SDOH begins to paint the picture of why COVID-19 is disproportionately affecting some populations.
“Socioeconomic status [SES] is the most powerful predictor of disease, disorder, injury and mortality we have,” says Tom Boyce, MD, chief of UCSF’s Division of Developmental Medicine within the Department of Pediatrics.” According to the WHO, the poor and those with less education present with higher prevalence of behavioral risk factors for chronic disease, including smoking, physical inactivity, and poor nutrition. They are also more likely to be overweight or obese. In the US in 2017, nearly 40 million people lived in poverty, including 4.7 million Americans age 65 and older. In terms of race/ethnicity, Native Americans have the highest poverty rate of any racial group at 24%, followed by Blacks (22%) and Hispanics (19%). And unfortunately, the latest CDC data support WHO conclusions: Current cigarette smoking is highest among Native Americans (~23% vs ~14% in the overall US population); Hispanics and non-Hispanic Blacks have the highest prevalence of physical inactivity (32% and 30%, respectively vs 15% in the overall US population); and while the overall rate of obesity in the US sits at ~42%, Blacks have the highest age-adjusted prevalence of obesity (~47%), followed by Hispanics (~45%).
Breaking out of these behavioral risk patterns is particularly difficult for those with low SES due to limited choices and opportunities presented by their surrounding environment, as well as inadequate healthcare and health education. Low SES communities are more likely to be found in areas without adequate sanitation, higher rate of environmental pollution, and limited access to fresh, healthy food. For example, The Navajo Nation has 13 grocery stores for a population of roughly 300,000 (to compare, Arizona has approximately 45 grocery stores per 300,000 people) and 30% of those on the reservation do not have access to running water in their homes. Moreover, long-standing farm subsidy policies have contributed to an environment where, “’energy-dense’ foods, such as fried or processed foods, tend to cost less on a per-calorie basis when compared with fresh fruit and vegetables.”
Low income families are also more likely to be uninsured, with minorities lacking insurance at a higher rate than non-Hispanic whites. Even those low-income families who qualify for Medicaid, often encounter gaps in access to healthcare service and variable quality care. And despite having a dedicated healthcare system (the Indian Health Service, IHS), Native American communities have very limited access to providers as a result of lack of adequate funding towards the IHS. Some patients on the Navajo Nation must travel over 200 miles round-trip to receive specialty care. Limited resources have hindered Native communities’ ability to implement public health promotion and disease prevention initiatives.
Finally, the higher rate of chronic disease in these vulnerable populations is further exacerbated by living and working conditions characterized by high density (e.g., nursing homes, urban settings, multi-generational households) where social distancing is difficult.
Given the key role of health status in covid morbidity and mortality, and the impact of SDOH on health status, what can the healthcare delivery system contribute to improving patient outcomes?
While the healthcare delivery system isn’t well equipped to take on the broad societal issues facing our vulnerable populations, healthcare delivery organizations can and should take some proactive steps to improve their overall health outcomes. At the minimum, healthcare providers must be aware of SDOH issues and how these issues impact patient health. Moreover, medical centers can track the health outcomes of all of their patients with chronic conditions by physician and SDOH characteristics, and develop interventions to improve patient health status. Providers can also implement regular SDOH screenings to identify patients at high risk for chronic conditions, and collaborate with social/community organizations on prevention and health promotion programs. Finally, the healthcare system could also benefit substantially from funding studies within actual delivery organizations to improve those factors that most impact our health over a lifetime – namely, our individual personal behaviors.
Thanks for this excellent summary of the role of the SDOH. Universal coverage and population health do rely on integrated social services. All of these, in one manner or another, must be grounded in health care if we wish to create a fully productive and civil society. Such an approach also has political appeal, a case I made in this 2017 piece: http://www.healthcommentary.org/2017/08/08/lets-make-america-healthy/
Best, MIke
Yes – thanks for great blog on SDoH and ramifications on population health – especially with covid.
Unfortunately – the more we spend on the health care industry – the less we spend on SDoH as a society. We continue to defund the most important factors of population health. We’ve heard of the “death spiral” in health insurance – this is the “death spiral of divestiture from SDoH”.
The poor and middle class has been burdened with higher and higher health care costs – spending much greater amounts on health insurance and having to decrease spending on all other items – food/housing/transportation/education. Obviously – not sustainable.
In this way – the health care industry might actually be contributing to a decline in population health. The argument could be made.