Patient Vignette

Danielle M. is a patient at her local hospital coming in for a check-up with her doctor regarding difficulty breathing over the past few days. As her doctor is preparing for her visit, she looks at the information stated in the electronic medical record:

·      Gender: Female

·      Age: 50

·      Reason for Visit: Difficulty Breathing for the past month

·      Language: English

·      Race/Ethnicity: Black/African-American

·      Smoker: Yes

            With these demographic "clues" from Danielle's electronic medical record, the doctor arrives at the reasoning for possible differential diagnoses to discuss with Danielle: chronic obstructive pulmonary disease (COPD) and asthma. The physician plans to perform a spirometer test, a method of assessing lung function by measuring the volume of air the patient is able to expel from the lungs after maximal inspiration. Spirometry is the primary method that clinicians use to evaluate lung function. Spirometry reports include a set of values based on the patient’s volumes of inspiration and expiration, and these values are compared with a range of volumes considered to be normal.

For Danielle, the pulmonary lung function test results did not result in a clinical diagnosis, because her spirometry results were within normal limits. “Ethnic” correction factors were applied to calculate these normal limits, and Danielle’s lung function test results may have resulted in a clinical diagnosis without them.

Danielle’s doctor tells her that they'll have to have a number of follow-up visits and additional lab testing in order to confirm her diagnosis. Danielle departs from the doctor's appointment disappointed and nervous that her breathing continues to be labored and difficult and that it will take several more appointments to find out what is going on. She is unable to make appointments in the upcoming month due to family obligations and her hectic work schedule. Afterwards, a medical student asks Danielle’s doctor if race correction factors could have impacted Danielle’s spirometry results. She replies, "Black people are always diagnosed and over-medicated. Thankfully these correction factors help with that.”

This anecdote is adapted from a true interaction one medical student had during a session with her preceptor. As medical students, we often hear statements like the one Danielle’s doctor made, where biological race is framed to us as a solution to health disparities. This framing makes it difficult to disentangle the insidious and harmful ways that the ingrained notion of biological race impacts patients like Danielle. However, challenging the notion of race as a biological trait should not be mistaken as advocacy for color-blind medicine. We want to be a part of medical practice that engages in antiracist medicine, not color-blind medicine. We advocate for medicine to acknowledge the role that flawed assumptions regarding biological race play in perpetuating racial health disparities.

This advocacy is vital because, as we show in the following example, race is dangerously built into algorithms that determine lung function, just as with kidney function. What could be considered “normal” function for Black people is repeatedly considered pathologic or unhealthy for white people. This discrepancy leads to late diagnoses and poorer treatment for Black people compared to their white counterparts.

Furthermore, the notions that racial and ethnic differences in lung capacity exist, and that these differences should be programmed into the diagnosis of lung disease, are fundamentally rooted in a history of racism. Next, we will elucidate this racist history, drawing largely from the critical work of Lundy Braun, including her book Breathing Race into the Machine.

Interest in modern spirometers first took hold as a means of assessing the fitness of police forces and military personnel and life insurance applicants in England during the outbreak of tuberculosis in the nineteenth century.[1] John Hutchinson, an English surgeon, was credited with inventing the spirometer in the 1840s and also coining the measurement “vital capacity,” after his assertion that such measurement was critical in assessing premature mortality.[2]

The application of Hutchinson’s spirometer quickly spread, including Samuel Cartwright’s use of spirometry on slavery plantations. Cartwright was a Southern physician and plantation owner who was the first person to use the spirometer as a tool for comparison of lung function between Black people and white people.[3] In particular, he asserted that “the expansibility of the lungs is considered less in the Black than the white race of similar size, age and habit.”[4] Benjamin Apthorp Gould published the first study in 1869 that would reinforce notions of biological inferiority of Black people with data on racial comparisons of lung function with large sample sizes and anthropometric measurements of Union soldiers. These assertions, alongside subsequent studies that found that slaves had poorer nutrition status and higher rates of pneumonia, typhoid fever, and respiratory illnesses, contributed to racist assertions that African American slaves had physical pathologies and thus needed to be kept under the institution of slavery.[5]

Political leadership who profited from the institutions of slavery, including Thomas Jefferson, reinforced the influence of notions of biological inferiority of Blacks and non-Caucasian populations. Despite taking part in asserting that “all men are created equal,” Thomas Jefferson, in his Notes on the State of Virginia, featured racial differences in lung function between white colonialists and slaves, asserting that there were marked distinctions between such groups and “a difference of structure in the pulmonary apparatus.”[6]

This brief history of key figures involved in the history of the spirometer illustrates how notions of biological racial difference in lung capacity and fitness related to the foundations of public health and slavery. In particular, the motivation for the creation of the spirometer by Hutchinson and its subsequent use by Cartwright and Gould to obtain scientific data claiming racial difference in lung function between slaves and colonialists was used to first assess and calculate the fitness disparities of diseased individuals in society and subsequently to achieve the subjugation of slaves and control of non-Caucasian populations. By obtaining “scientific” anthropometric information that attempted to objectively assert the biological inferiority of Black people, slavery was further justified through medical and public health institutions and methods.

Perhaps the most striking element of this history is how its roots continue to be embedded in how physicians conduct differential diagnoses and patient assessments every day due to recommended guidelines. Medicine continues to uphold racist notions of biological inferiority in lung function.

For example, the web page on UpToDate regarding spirometry states the following:

Healthy African-Americans have spirometric values that are approximately 12 percent lower than Americans of Caucasian descent of the same age, sex, and height. This difference is, in part, due to a difference in the ratio of trunk size to standing height, i.e., African-Americans have longer legs for a given height. Genetics and nutritional factors may also play a role in differences by race/ethnicity.[7]

UpToDate is considered an “evidence-based clinical resource” that clinicians use every single day after patient appointments for information about medications, diseases, clinical guidelines, and more. This statement by a frequently used, highly regarded medical resource is problematic for many reasons. First of all, we know that when studies use the category “African Americans,” race is typically self-identified or guessed by the clinician. To think that a statement as simplistic as “African Americans have longer legs for a given height” could possibly apply to all people who would fall into that category is absurd. Secondly, it is unclear how trunk size to standing height ratio can be emphasized as so critical in explaining spirometric values.

UpToDate cites two articles to support their claim. The first article cites another article that cites another article, and all the articles in this chain repeat the same statement without further explanation. For example, the first citation by UpToDate states, “African-Americans on average having a smaller trunk:leg ratio than do Caucasians,” and does not offer any evidence for why this observation should be singularly focused on over environmental and structural factors as a basis for correction factors in spirometry.[8] The second citation by UpToDate regarding trunk to height ratio says, “Differences due to ethnicity are not well defined.”[9] If the differences are so poorly defined, it is shocking how a resource so frequently used as UpToDate can so uncritically repeat that conclusion. Additionally, despite this lack of evidence, if trunk to standing height ratio really is the key factor in determining spirometric values, then race is a poor proxy for this ratio.

In practice, these assumptions about differences in lung function are built into spirometers as “race correction” factors that lead to different diagnoses for patients of different races. Anne Fausto-Sterling describes, “Technicians present spirometry results ‘corrected’ for race, so that for an African American to receive a diagnosis of impaired lung function—for example, a worker seeking disability compensation for lung damage from asbestos—he or she has to be dramatically sicker relative to a white American before receiving an equivalent disease diagnosis.”[10] Here, Fausto-Sterling is referencing a case in 1999 in which Owens Corning, a company that sickened thousands of workers through its asbestos-containing products, requested that African American workers filing lawsuits against the company show that they have worse scores on lung function tests than white workers as a result of asbestos exposure in order to qualify for a trial against the company.[11] Owens Corning cited “medical evidence” that Black people have different lung capacities than white people.

Currently, the American Thoracic Society (ATS) specifically recommends that the Global Lung Function Initiative (GLI) 2012 multiethnic spirometry reference values be used in North America and elsewhere for the ethnic groups represented.[12] The ATS establishes standards of care relating to respiratory disorders through the publication of statements, workshop reports, and clinical guidelines that health providers and trainees across the country are expected to be up to date on. There are several issues with guidelines based off of the ATS recommendations. First, the popularly used GLI reference values are extracted from datasets of overwhelmingly Caucasian populations. In addition, GLI reference values confound false notions of biological race with environmental exposures and stressors, as the following quotation from the GLI authors demonstrates:

The well documented ethnic and racial differences in pulmonary function arise from differences in body build (such as chest size or the ratio of sitting to standing height), socio-economic status (which determines bodily development in early life and leads to secular trends in body size and pulmonary function), growing up at altitude, and possibly other environmental factors. In the present study race and ethnicity were self-reported, which may not be accurate enough for clinical purposes. Indeed, in the absence of genetic typing, predicted values in self-reported African Americans may be biased by up to 200 mL.”[13]

These current ATS and GLI guidelines demonstrate the blatant confusion and oversimplification of using categories of race as a means of adjusting for spirometry values. Race is not the same as ethnicity, which is not the same as body build, which is not the same as socioeconomic status, which is not the same as the environment. It cannot be used as a proxy for these structural and environmental factors, which have repeatedly been proven to directly impact lung function on their own.

Lundy Braun further elaborates on this unnecessary emphasis on racial correction factors despite greater evidence supporting how environmental factors, not race itself, mediates lung disease:

There have been scientific studies showing that people who live around high pollution areas have lower lung capacity. High pollution areas also map onto minority status. Why we have chosen both in the US and internationally to focus on race to the exclusion of social class, I can only speculate. One piece of the story is that the accumulation of scientific research around a particular idea can make it hard to dislodge. With the spirometer, having the correction factor actually built into the machine makes racial assumptions invisible.”[14]

The consequences of the oversimplification of structural and environmental factors into racial correction factors are that these guidelines are transferred from institutional memory into everyday physician practice that affect patients, contributing to poor treatment and diagnosis assessment for people of color and subsequent racial health disparities. Despite these concerns, the ATS fails to address any responsibility in contributing to racial health disparities by encouraging the practice of applying haphazard guidelines such as those of the current spirometry reference values according to race and ethnicity. By failing to see or challenge their inappropriate use of race and the unintended consequences of the recommendations, the ATS and the clinicians who follow such recommendations continue to perpetuate the unjust, racist framework upon which the spirometer was founded.

Furthermore, the continued presence of the racist history of establishing race-based differences in lung function within the modern-day practice of pulmonology signals how the medical community has refused to address this hidden history of racism and subjugation of Black and brown bodies. There is a profound need for this history to be interrogated, discussed in dialogue within the medical community, and incorporated into medical practice. This conversation has the potential to shift focus away from misguided notions of biological difference. Medicine must acknowledge how racism and social inequalities have had a harmful impact on health outcomes in order to address racial health disparities related to lung function.