Health Disparities Among the Black Population in the U.S.

As Black History Month comes to a close, we’ve been discussing the health disparities the Black population faces in the United States. They are the result of a combination of factors such as poverty, racism, and access to health care, among others. The causes of these health disparities are rooted in a history of racial oppression in the United States. In fact, the utilization of race in medicine in the United States can be traced to Carl Linnaeus, who is recognized as the father of modern taxonomy. Linnaeus based his theories and work on Francis Bernier’s proposals from the 1700s, which classified humans into four major racial groups (American, European, Asian and African). 

As a result of this historical racial oppression, the health of the Black population in the United States is significantly worse than that of other racial and ethnic groups. According to the Office of Minority Health, part of the Department for Health and Human Services, compared to their white counterparts, African Americans endure a disproportionately higher rate of chronic illnesses such as heart disease, stroke, and diabetes, as well as higher rates of infant mortality. Even though there may be an increased genetic susceptibility risk for some conditions correlated with Black ancestry, social determinants of health play a critical role.

Social Determinants of Health Impacting Healthcare

Social determinants of health (SDoH), the conditions in which people are born, grow, live, work, and age, play a significant role in the higher occurrence of cardiovascular disease (CVD) among Black people. 

The following are some of the ways in which SDoH impact the higher occurrence of CVD among Black people:

1. Limited access to healthcare: The Black population is more likely to experience barriers to accessing healthcare, including a lack of health insurance, lack of transportation, and limited availability of healthcare facilities in their communities. These barriers can result in delays in the diagnosis and treatment of CVD and may contribute to worse outcomes.
2. Racial discrimination and stress: Black people experience racial discrimination and stress, which can lead to chronic stress, inflammation, and other physiological responses that increase the risk of CVD.
3. Poverty and limited resources: Black people are more likely to live in poverty and have limited resources, which can contribute to a lack of access to healthy foods, safe environments for physical activity, and other resources that are important for preventing CVD.
4. Education and literacy: Black people are more likely to have lower levels of education and health literacy, which can make it more difficult to understand the importance of lifestyle changes and follow treatment plans for CVD.

The Prevalence of Cardiovascular Disease Among The Black Population

Cardiovascular disease (CVD) is a group of conditions that affect the heart and blood vessels, including coronary artery disease, heart failure and stroke. The Black population in the United States is disproportionately affected by CVD, with higher rates of risk factors and, alarmingly, worse outcomes compared to other ethnic groups. In fact, according to the American Heart Association, the Black population is more likely to have CVD than white, and they develop CVD at an earlier age.

One of the major risk factors for CVD is hypertension or high blood pressure. Black persons have a higher prevalence of hypertension than any other racial or ethnic group in the United States, with more than 40% of Black adults affected.

Kidney Disease Disproportionately Affecting Blacks in America

When hypertension goes untreated, it can damage the blood vessels in the kidneys, leading to chronic kidney disease (CKD). Kidney disease disproportionately impacts communities of color. In fact, Black or African Americans are almost four times more likely, and Hispanics or Latinos are 1.3 times more likely to have kidney failure than white Americans. Black people present the highest prevalence of major causes of kidney disease, including diabetes, hypertension, and cardiovascular disease. Although they represent 13.5% of the population, Black people are accountable for up to 35% of dialysis patients.

Routine kidney health tests can help detect these conditions early, allowing for earlier intervention and treatment. With early detection, lifestyle changes, medication, and other interventions can be initiated to help prevent further damage to the kidneys and other organs.

A Kidney Health Evaluation self-collection kit can measure how well the kidneys are functioning and can detect signs of CKD. If a kidney health test reveals signs of CKD, it may indicate that the individual has been living with untreated hypertension, which has caused damage to the kidneys.

The use of eGFR is a crucial clinical tool in diagnosing chronic kidney disease. Its primary role is to facilitate a more straightforward interpretation of biomarkers of renal disease. 89% of labs surveyed by the College of American Pathologists (CAP) report eGFR alongside serum creatinine, as do the CLIA Certified and CAP Accredited labs we partner with at ixlayer.

Overcoming Racial Assumptions In CKD Lab Results

Historically, when GFR was directly measured from endogenous clearance of creatinine from exogenous substances such as iothalamate, there was a difference in GFR between Black and non-Black persons. That observation guided the incorporation of a race coefficient in estimating equations that would inflate GFR estimates for Black patients in order to generate unbiased GFR estimates in Black and non-Black populations. 

Yet, concern has arisen that the inclusion of race as a coefficient in eGFR equations inequitably represents GFR estimates in Blacks and lacks a biological basis.

Estimated glomerular filtration rate (eGFR) is one of the primary diagnostic methods for detecting and managing kidney diseases. The eGFR equation includes age, sex, race and/or body weight to approximately measure kidney function. Nevertheless, race is a social, not a biological, construct.

It has also been deeply described that the “clinical” categorization of race (starting from the fact that it has been misused as it represents a social aspect) doesn’t correlate with genotyped ancestry. Arbitrary phenotypic elements such as type of hair or skin color cannot determine race or ancestry; thus, they shouldn’t be used as a clinical determinant.

Fortunately, this concern has been raised and discussed globally, and on March 9, 2021, a joint statement from the presidents of the American Society of Nephrology and the National Kidney Foundation was published stating that race should be removed from estimates of kidney function. Paul M. Palevsky, MD, FASN, FNKF, president of the National Kidney Foundation, said after the official recommendation was released, “The use of race in clinical algorithms normalizes and reinforces misconceptions of racial determinants of health and disease. We must move beyond this if we are to address the racism and racial disparities that impede the care of people with kidney disease.”

Conclusion

This update was a step forward for a more equitable healthcare experience for the Black population. To further address these racial disparities in the awareness, diagnosis, and treatment of kidney disease, the National Kidney Foundation is focusing on the following areas:

1. Eliminating racial and ethnic disparities in access to transplantation
2. Improving CKD diagnosis and treatment to delay kidney failure
3. Increasing access to home dialysis for diverse populations
4. Reducing out-of-pocket costs for kidney patients

A shift is needed in the way healthcare is structured and perceived in the United States. To address the impact of social determinants of health on the higher occurrence of CVD among Black individuals, it is essential to correct the underlying social and economic factors that contribute to these disparities. This includes promoting policies for reducing poverty, improving access to healthcare and reducing discrimination and stress. Additionally, improving education and health literacy can help individuals better understand the importance of preventive measures and treatment for CVD. 

By addressing these factors, we can help improve outcomes for Black people. In fact, according to the American Heart Association, getting checked regularly and working with providers to decrease risk factors can help improve heart health. Patients and providers alike must have better access to the preventive healthcare tools needed to create a more accessible healthcare model that enables us to provide quality preventive care regardless of where and who we are.

 

References

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