Marked changes in spirometry results were found when race-neutral equations replaced older, race-based equations in assessing lung health, a recent JAMA Pediatrics study reports.
Most measures of lung function decreased for Black and Hispanic children when using the neutral equations, while results slightly increased for white children, the authors found.
After decades during which race was considered as a factor in interpreting spirometry measures, an expert panel of the American Thoracic Society in 2023 issued a statement recommending that race and ethnicity be dropped as factors.
“Society guidelines suggest that we should use these race-neutral equations, but no one really knew what would happen when we did,” said Christian Rosas-Salazar, M.D., an assistant professor of pediatrics at Monroe Carell Jr. Children’s Hospital at Vanderbilt.
“We did this study to understand what would happen in individual measurements – and also in terms of different patterns of obstruction or restriction – if we used one equation versus the other.”
“Society guidelines suggest that we should use these race-neutral equations, but no one really knew what would happen when we did.”
Poorer Lung Function
The study’s results suggest some lung health issues may not be identified using the earlier equation, since the race-neutral version reported more irregularities among Black children.
The forced expiratory volume in one second (FEV1) and forced vital capacity (FEC) z scores decreased in Black children, while “the number of tests with a normal pattern decreased and nearly one in five tests transitioned to a different spirometry pattern after implementing [race-neutral equations],” the authors reported.
Spirometry measures were slightly better among white children when the race-neutral equations were used.
“The changes differed dramatically by race,” the authors wrote.
The original equations were based on the belief that racial characteristics affect the function of children’s respiratory system. However, no robust data exist to support the inclusion of race to control spirometry results, nor is there any biological reason to use race.
“In the past, a lot of incorrect assumptions had been made that race could impact the size of the lungs or thorax,” he said. “We had these equations to tell us what was normal, and they were based on age, sex, height, and race. Age, sex and height are important biological factors, but race is not.”
Factors that may matter include social determinants of health, exposure to pollution and tobacco smoke, and other race-related factors such as socioeconomic status and nutrition, he said.
“Race-free equations get us closer to more correctly assessing or diagnosing children of underrepresented minorities with chronic lung diseases and can potentially decrease health disparities in pediatric pulmonology.”
Decade of Data
Pulmonary specialists have been interested in knowing what to expect when a child assessed using race-based measurements is re-assessed using race-neutral criteria. Also of concern were patients of mixed race.
“How were we supposed to use race-based equations in mixed-race children? We didn’t have specific equations for them,” Rosas-Salazar said.
The researcher’s large, cross-sectional study of spirometry tests involved children ages 6 to 21 years between 2012 and 2022. All the youngsters were seen at either Vanderbilt Children’s Hospital or the University of Pittsburgh Medical Center’s Children’s Hospital.
The study defined “race” as that reported by the patients’ parent or guardian when designating their child as Black, Northeast Asian, Southeast Asian, white or other – including mixed race.
The research showed that, in Black children, the number of tests with a normal pattern decreased from 68.7 to 61.9 percent following implementation of the new questions. In most cases, it was due to transition from a “normal” pattern into a “suspected restrictive” pattern or “uncategorized” under the newer guidelines.
Potential to Reduce Disparities
Providers, including those in primary care, need to understand the importance of using race-neutral equations when determining normal values for children. They should also expect changes to occur when implementing race-neutral equations, especially in Black children.
“I believe that race-free equations get us closer to more correctly assessing or diagnosing children of underrepresented minorities with chronic lung diseases and can potentially decrease health disparities in pediatric pulmonology,” Rosas-Salazar said.
