New Research Underscores Racial Health Disparities In Lung Capacity Testing
KPBS Midday Edition Segments / March 10, 2021
The COVID-19 Pandemic has highlighted a number of racial health disparities across the nation. But as researchers and physicians continue to study the severe effects of COVID-19 on the body, a new report from UC San Diego Health suggests that long-standing tests used to determine lung capacity are actually rife with archaic and, in some cases, racist components that could lead to a misdiagnosis in patients of color.
Speaker 1: 00:00 The COVID-19 pandemic has highlighted a number of racial health disparities across the nation. But as researchers and physicians continue to study the severe effects of COVID 19 on the body, a new report from UC San Diego health suggests that long standing test used to determine lung capacity or actually rife with archaic. And in some cases, racist components that could lead to a misdiagnosis in patients of color. Joining me today are two of the researchers on that report, Dr. Amy naan and Dr. A tool. Malhotra welcome to you both.
Speaker 2: 00:34 Thank you. Thank you, Dr. Nan,
Speaker 1: 00:36 I'll start with you. Certain medical tests for determining lung capacity have come under scrutiny after the U S food and drug administration determined that these tests have limited utility among people of color. How did the FDA come to make that assessment?
Speaker 2: 00:51 So limited utility is probably in reference to the pulse oximetry tests that you're referring to. And those are, um, tools that are designed to read blood flow through the skin and darker skin color. Actually can't be read through as easily as later skin color. And so it turns out that those pulse oximetry readers just can't read blood flow as well with darker skin and work less well than with people of darker skin color. Yeah.
Speaker 1: 01:19 And let me ask you this, another of those lung capacity tests, uh, spirometers can provide much more accurate results. However, this kind of test is used with a race-based modification that has racist origins. How did this come to be?
Speaker 2: 01:35 The spirometer is the one that we wrote about in our recent article, and that is a tool that measures lung capacity. And so in the spirometry measurement, it actually is corrected for automatically in most barometers to adjust black lung function, 10 to 15% higher, because the assumption is that black lungs, uh, have 10 to 15% lower capacity than white lungs. And this is based on, uh, really old historical data dating all the way back to Thomas Jefferson, um, where he assumed and, um, reported that black lungs were less, uh, had lower capacity than white lungs. And so this data has been shown over and over through the years that there is lower lung capacity at a population level. And so they've built these corrections into the tools that we use to measure lung capacity. But the problem is we don't actually know why there's lower lung capacity in black populations and it's assumed to be normal. And so we adjusted leading to potential underdiagnosis among black people. If their lung capacity is lower, but it could be an environmental factor that's driving this difference and not a genetic factor. And the assumption is that they are genetically different and that's why they, they use a different normal standard for black lungs than white lungs.
Speaker 1: 02:56 Dr. Malhotra how often do you that leads to misdiagnosis?
Speaker 3: 03:01 No, we really don't know. That's a study we're doing now where we're collecting data in actual survivors of COVID to see how many of them are in the normal or abnormal range. These, uh, assumptions about what's normal as Dr. Nonsense or based on historical assumptions. That's really, aren't well validated with scientific data. So we're now looking at some African-American survivors of COVID to see how many of them are having these adjustments have somebody who's at 70% of normal, and that is adjusted up to, to put them into the normal range. We might not give them appropriate treatment. Cause we'd say they're normal inappropriately
Speaker 1: 03:35 In Dr. Malhotra because COVID-19 affects lung capacity. We've seen an increase in the use of spirometry tests. Uh, how have these so-called race modifications used in these kinds of tests exacerbated existing racial health disparities in America?
Speaker 3: 03:51 Yeah, so it's something that not all of us are aware of, but there's a lung doctor. We use pyrometry all the time to assess lung capacity. We have people blow into a device and measure how much volume or flow comes out of their lung and what's normal or abnormal. So it depends on the eyes of the beholder. Sometimes what we end up doing is saying what it is, what the value is as a percent of predicted, but the predictors based on these historical assumptions, which is on cases are flawed
Speaker 1: 04:17 And Dr. Non this research indicates there's no major genetic marker. As you mentioned, that can explain racial differences in lung function. How do you hope this finding will highlight racism in the field of health?
Speaker 3: 04:28 That's right there hasn't been any genetic study that explains racial differences in lung function with any particular genetic marker. So I think the future of this research really should focus on what kind of environmental exposures might also be contributing to racial differences among function factors, such as air pollution, smoke, exposure, intrauterine growth restriction. All of these things over the life course can affect lung function. And so I think a focus on these factors in research and trying to get to the bottom of what's actually contributing to lung function differences without just assuming they're genetic is it's the next step.
Speaker 1: 05:09 And Dr. Malhotra, is it possible that doctors could be missing or looking past critical diagnosis, uh, and people of color due to these flawed testing methods?
Speaker 3: 05:19 Yeah, it's not just possible. It's actually likely because the normal values I get when I do one of these tests are adjusted in ways that are not accurate to take an extreme example. If there was a group of people that smoked a lot of cigarettes, let's say smoke three packs a day for 20 years, just to make a point, if you adjusted for that. So that's normal, then nobody would have emphysema or smoking related disease. Cause he had said that's normal and that's obviously inappropriate. Whereas Dr is emphasizing understanding why the lung function is a certain way is important. If the genetic and environmental and other factors coming into play, it's important that doctors recognize that and say, what's from COVID what's some other factors then try and treat accordingly.
Speaker 1: 05:59 What will it take to change the existing practice to make the measurements more equitable and accurate for everyone who's tested?
Speaker 3: 06:07 I think the first step is raising awareness. Uh, even though I'm a lung, uh, physician, I can tell you that other lung doctors don't necessarily recognize where those factors came from and the truth be told, I wasn't fully aware of the, the Thomas Jefferson thing about inferior black lens until Dr. Naan brought that to my attention. So even though that sounds absurd, that was, uh, the dogma that we weren't aware of. So the first step is raising awareness. The next step is added research. And so looking at what happens to different people of different races, different ethnicities as they survive COVID is an important next step for Caucasian person blew out of their lungs, three and a half liters and an African-American blew out of the lungs three liters. There's a difference in the volume that they're blowing out their lungs. If you make an adjustment saying, well, it's normal for them, then you'll end up concluding that everybody's normal. But the fact that their volumes are different or their air flows are different, maybe because they have disease and it's not something you want to adjust for.
Speaker 1: 07:04 And, uh, Dr. Naan, you're quoted as saying that body proportion, socioeconomic status and occupational hazard impact lung capacity and not necessarily a person's race. How do you hope this research will help impact future clinical reporting with regards to,
Speaker 2: 07:20 I hope that, um, future clinicians actually do holistic interviews, asking people about all the exposures that they're encountering, smoke exposure, lifetime smoke, exposure, occupational hazards, and, and don't just automatically adjust for race in their spirometry readings or in any measurement or clinical diagnosis that uses race. This is not a situation actually specific to lung capacity, but it's common across many medical diagnoses. Um, there's differences in the way kidney function is, uh, estimated by race there's differences in, in estimates for risk of vaginal birth. After C-section many different diseases have risk calculators with race built into them. And I hope that we actually do closer examinations of what's driving these racial differences before we continue using these race adjustments, because we don't know what's causing racial differences, or if they're even real.
Speaker 1: 08:18 I've been speaking with Dr. Amy naan and Dr. Atoll Malhotra of UC SD health. Thank you both. Thank you. Thank you.