Effect of Race and Ethnicity on Pulmonary Function Testing Interpretation: An American College of Chest Physicians (CHEST), American Association for Respiratory Care (AARC), American Thoracic Society (ATS), and Canadian Thoracic Society (CTS) Evidence Review and Research Statement

Discussing and Teaching About Race and Health Inequities

Health inequities are prevalent in our medical institutions and result in unfair access to and delivery of health care. Some of the most profound health disparities are related to race, which has erroneously been used to make biological inferences to explain disease states in medicine. Our profession continues to shift away from such race-based medical narratives, which do not examine how social determinants of health, social injustice, systemic racism, and existing power structures shape health outcomes toward a health equity mindset and race-conscious medicine. Clinician educators are responsible for teaching and engaging with learners around issues of inequity in medicine, although many may feel they lack the knowledge or skills to do so. Opportunities for conversations on health equity abound, either as a response to statements made by clinical peers or patients, or through direct clinical care of affected populations. In this paper, we focus our discussion of health equity around the topic of race corrections in spirometry, which is one of several salient areas of conversation in the field of pulmonary medicine undergoing reconciliation. We review basic definitions and concepts in health equity and apply three strategies to engage in conversations around equity with colleagues and learners: actively learning and reflecting on health inequities, recognizing and naming inequities, and consciously role-modeling equity-conscious language and care. We also will summarize strategies for implementing health equity concepts into the continuum of medical education and our clinical learning environments.

Race Adjustment of Pulmonary Function Tests in the Diagnosis and Management of COPD: A Scoping Review

Aim

Increasing evidence suggests that the inclusion of self-identified race in clinical decision algorithms may perpetuate longstanding inequities. Until recently, most pulmonary function tests utilized separate reference equations that are race/ethnicity based.

Purpose

We assess the magnitude and scope of the available literature on the negative impact of race-based pulmonary function prediction equations on relevant outcomes in African Americans with COPD.

Methods

We performed a scoping review utilizing an English language search on PubMed/Medline, Embase, Scopus, and Web of Science in September 2022 and updated it in December 2023. We searched for publications regarding the effect of race-specific vs race-neutral, race-free, or race-reversed lung function testing algorithms on the diagnosis of COPD and COPD-related physiologic and functional measures. Joanna Briggs Institute (JBI) guidelines were utilized for this scoping review. Eligibility criteria: The search was restricted to adults with COPD. We excluded publications on other lung disorders, non-English language publications, or studies that did not include African Americans. The search identified publications. Ultimately, six peer-reviewed publications and four conference abstracts were selected for this review.

Results

Removal of race from lung function prediction equations often had opposite effects in African Americans and Whites, specifically regarding the severity of lung function impairment. Symptoms and objective findings were better aligned when race-specific reference values were not used. Race-neutral prediction algorithms uniformly resulted in reclassifying severity in the African Americans studied.

Conclusion

The limited literature does not support the use of race-based lung function prediction equations. However, this assertion does not provide guidance for every specific clinical situation. For African Americans with COPD, the use of race-based prediction equations appears to fall short in enhancing diagnostic accuracy, classifying severity of impairment, or predicting subsequent clinical events. We do not have information comparing race-neutral vs race-based algorithms on prediction of progression of COPD. We conclude that the elimination of race-based reference values potentially reduces underestimation of disease severity in African Americans with COPD.

The Current State of Health Inequities in COPD

An understanding of the health inequities that surround the treatment and prevention of COPD is required to address the barriers that hinder improvement of care for underserved populations. This scoping review was conducted to identify the existing evidence of social factors that affect the health, health-care access, and health-care quality of patients with COPD within the United States, and to identify gaps in knowledge to help direct future research. We followed the guidelines from the Joanna Briggs Institute and Preferred Reporting Items for Systematic reviews and Meta Analyses Extension for Scoping Reviews. In July 2022, a literature search by using Ovid (Embase) and MEDLINE (PubMed) databases was conducted to identify articles on COPD, published between 2016 and 2021, written in English, and that investigated at least one health inequity as defined by the National Institutes of Health. All studies were screened for inclusion criteria and were extracted in a masked, duplicate manner. Each health inequity was investigated, extracted, and summarized. Thirty articles were screened in full text, and 19 were found to meet inclusion criteria. Common social factors investigated in the COPD literature included race/ethnicity, income, and education. Since the implementation of the National Institutes of Health's sex and gender minority category in 2016, only one study within our sample examined LGBTQ+ (lesbian, gay, bisexual, transgender, queer [or sometimes questioning], and others) patients with COPD. The least commonly investigated social factors that affect patients with COPD were rural/under-resourced (geography), sex and gender, and LGBTQ+ affiliation. In addition, occupational status was not investigated by any included studies in our sample. Our scoping review underlines the lack of research with regard to inequities that affect patients with COPD. We propose researching hormone replacement therapy's impact on lung function in transgender and nonbinary patients with COPD. Implementation science studies are suggested to enhance intervention for COPD medication adherence among racial/ethnic minority groups, given the intersectionalities of social factors that disproportionately affect this population. We, also recommend developing telemedicine pulmonary rehabilitation technology for rurally located patients with COPD.

Application of Global Lung Function Initiative Global Spirometry Reference Equations across a Large, Multicenter Pulmonary Function Lab Population

Rationale: Global Lung Function Initiative (GLI) Global spirometry reference equations were recently derived to offer a "race-neutral" interpretation option. The impact of transitioning from the race-specific GLI-2012 to the GLI Global reference equations is unknown. Objectives: Describe the direction and magnitude of changes in predicted lung function measurements in a population of diverse race and ethnicity using GLI Global in place of GLI-2012 reference equations. Methods: In this multicenter cross-sectional study using a large pulmonary function laboratory database, 109,447 spirometry tests were reanalyzed using GLI Global reference equations and compared with the existing GLI-2012 standard, stratified by self-reported race and ethnicity. Measurements and Main Results: Mean FEV1 and FVC percent predicted increased in the White and Northeast Asian groups and decreased in the Black, Southeast Asian, and mixed/other race groups. The prevalence of obstruction increased by 9.7% in the White group, and prevalences of possible restriction increased by 51.1% and 37.1% in the Black and Southeast Asian groups, respectively. Using GLI Global in a population with equal representation of all five race and ethnicity groups altered the interpretation category for 10.2% of spirometry tests. Subjects who self-identified as Black were the only group with a relative increase in the frequency of abnormal spirometry test results (32.9%). Conclusions: The use of GLI Global reference equations will significantly impact spirometry interpretation. Although GLI Global offers an innovative approach to transition from race-specific reference equations, it is important to recognize the continued need to place these data within an appropriate clinical context.

Applicability of the Global Lung Function Initiative prediction equations in Hong Kong Chinese children

BACKGROUND AND OBJECTIVE

This study aimed to assess the applicability of the Global Lung Function Initiative (GLI) prediction equations for spirometry in Hong Kong children and to develop prediction equations based on the Generalized Additive Models for Location, Scale, and Shape (GAMLSS) modeling.

METHODS

Healthy Chinese children and adolescents aged 6-17 years old were recruited from randomly selected schools to undergo spirometry. The measurements were transformed to z-score according to the GLI-2012 equations for South East (SE) Asians and the GLI-2022 global race-neutral equations. Prediction equations for spirometric indices were developed with GAMLSS modeling to identify predictors.

RESULTS

A total of 886 children (477 boys) with a mean age of 12.5 years (standard deviation [SD] 3.3 years) were included. By the GLI-2012 SE Asian equations, positive mean z-scores were observed in forced expiratory volume in 1 s (FEV1 ) (boys: 0.138 ± SD 0.828; girls: 0.206 ± 0.823) and forced vital capacity (FVC) (boys: 0.160 ± 0.930; girls: 0.310 ± 0.895) in both sexes. Negative mean z-scores were observed in FEV1 /FVC ratio (boys: -0.018 ± 0.998; girls: -0.223 ± 0.897). In contrast, negative mean z-scores in FEV1 and FVC, and positive mean z-scores in FEV1 /FVC were observed when adopting the GLI-2022 race-neutral equations. The mean z-scores were all within the range of ±0.5. By GAMLSS models, age and height were significant predictors for all four spirometric indices, while weight was an additional predictor for FVC and FEV1 .

CONCLUSION

Our study provided data supporting the applicability of the GLI prediction equations in Hong Kong Chinese children. The GLI-2012 equations may underestimate FEV1 and FVC, while the GLI-2022 equations may overestimate the parameters, but the differences lie within the physiological limits. By GAMLSS modeling, weight was an additional predictor for FVC and FEV1 .

Towards a Race-Neutral System of Pulmonary Function Test Results Interpretation

It has been observed widely that, on average, Black individuals in the United States have lower FVC than White individuals, which is thought to reflect a combination of genetic, environmental, and socioeconomic factors that are difficult to disentangle. Debate therefore persists even after the American Thoracic Society's 2023 guidelines recommending race-neutral pulmonary function test (PFT) result interpretation strategies. Advocates of race-based PFT results interpretation argue that it allows for more precise measurement and will minimize disease misclassification. In contrast, recent studies have shown that low lung function in Black patients has clinical consequences. Furthermore, the use of race-based algorithms in medicine in general is increasingly being questioned for its risk of perpetuating structural health care disparities. Given these concerns, we believe it is time to adopt a race-neutral approach, but note that more research is urgently needed to understand how race-neutral approaches impact PFT results interpretation, clinical decision-making, and patient outcomes. In this brief case-based discussion, we offer a few examples of how a race-neutral PFT results interpretation strategy will impact individuals from racial and ethnic minority groups at different scenarios and stages of life.